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Giltmier AJ, Higano NS, Woods JC, Kingma PS. Evaluation of regional lung mass and growth in neonates with bronchopulmonary dysplasia using ultrashort echo time magnetic resonance imaging. Pediatr Pulmonol 2024; 59:55-62. [PMID: 37787390 PMCID: PMC10841165 DOI: 10.1002/ppul.26705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 09/08/2023] [Accepted: 09/19/2023] [Indexed: 10/04/2023]
Abstract
RATIONALE Bronchopulmonary dysplasia (BPD) is the most common long term pulmonary morbidity in premature infants and is characterized by impaired lung growth and development. We hypothesized that lung mass growth is a critical factor in determining outcomes in infants with BPD. OBJECTIVES To measure regional lung density and mass in infants with BPD and compare to clinical variables. METHODS We conducted a retrospective cohort study of neonates (n = 5 controls, n = 46 with BPD). Lung mass and lung density were calculated using ultrashort echo time (UTE) magnetic resonance imaging (MRI). MEASUREMENTS AND MAIN RESULTS Lung mass increased with increasing corrected gestational age at the time of MRI in all patients. Total, right, and left lung mass in infants with BPD trended higher than control infants (65.7 vs. 49.9 g, 36.2 vs. 26.8 g, 29.5 vs. 23.1 g, respectively). Babies with BPD who survived to discharge had higher relative lung mass than control infants and infants with BPD that did not survive to discharge (21.6 vs. 15.7 g/kg, p = .01). There was a significant association between the rate of lung mass growth and linear growth at the time of MRI (p = .034). CONCLUSIONS Infants with BPD are capable of building lung mass over time. While this lung mass growth in infants with BPD may not represent fully functional lung tissue, higher lung mass growth is associated with increased linear growth.
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Affiliation(s)
- Andrew J Giltmier
- University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Cincinnati Children's Hospital Medical Center, The Perinatal Institute, Cincinnati, Ohio, USA
| | - Nara S Higano
- Cincinnati Bronchopulmonary Dysplasia Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Radiology, Cincinnati Children's Hospital Medical Center, Center for Pulmonary Imaging Research, Division of Pulmonary Medicine, Cincinnati, Ohio, USA
- Cincinnati Children's Hospital Medical Center, Division of Pulmonary Medicine, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Jason C Woods
- Cincinnati Bronchopulmonary Dysplasia Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Radiology, Cincinnati Children's Hospital Medical Center, Center for Pulmonary Imaging Research, Division of Pulmonary Medicine, Cincinnati, Ohio, USA
- Cincinnati Children's Hospital Medical Center, Division of Pulmonary Medicine, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Paul S Kingma
- Cincinnati Children's Hospital Medical Center, The Perinatal Institute, Cincinnati, Ohio, USA
- Cincinnati Bronchopulmonary Dysplasia Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Radiology, Cincinnati Children's Hospital Medical Center, Center for Pulmonary Imaging Research, Division of Pulmonary Medicine, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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Kovatis K, Mackley A, Traczykiewicz S, Subedi K, Rahman T, Shaffer TH. Oxygen saturation and work of breathing indices in preterm infants with bronchopulmonary dysplasia compared to healthy preterm infants at discharge. J Neonatal Perinatal Med 2024; 17:589-595. [PMID: 38968059 DOI: 10.3233/npm-230222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2024]
Abstract
BACKGROUND Thoracoabdominal asynchrony (TAA) is commonly seen in preterm infants. Respiratory inductive plethysmography (RIP) is a noninvasive way to objectively assess work of breathing (WOB) indices. The impact of bronchopulmonary dysplasia (BPD) on TAA at discharge has not been established. The aim of this study is to compare WOB indices in premature infants with a diagnosis of BPD to premature infants without a diagnosis of BPD at discharge. METHODS A prospective, observational study of premature infants (<32 weeks gestation) at discharge during quiet breathing in the supine position. RIP noninvasively measured WOB indices. A high-resolution pulse oximeter collected oxygen saturation and heart rate data. RESULTS This study included thirty-one infants with BPD and thirty-four infants without BPD. Infants diagnosed with BPD had increased phase angle [BPD Φ = 73 . 90 (8.2) vs NoBPD Φ = 52.6 (8.2), p = 0.039]. Infants diagnosed with BPD had decreased saturations [BPD SpO2 = 96% (0.4) vs NoBPD Sp02 98% (0.3), p=<0.001], increased time with saturations less than 85% [BPD % =2.74 (0.7) vs NoBPD % =0.91 (0.4), p = .018], and increased time with saturations less than 80% [BPD % =1.57 (0.5) vs NoBPD % =0.52 (0.3), p = 0.045]. There was no difference in heart rate or breaths per minute for infants with BPD versus controls. CONCLUSION Premature infants with BPD demonstrated increased TAA and had lower saturations compared to infants without BPD at discharge despite being chronologically older and being discharged at an older corrected gestational age. The impact of BPD on breathing patterns persists at discharge and suggests these patients may have residual lung and/or respiratory muscle dysfunction.
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Affiliation(s)
- K Kovatis
- Department of Neonatology, ChristianaCare. Newark DE, USA
| | - A Mackley
- Department of Neonatology, ChristianaCare. Newark DE, USA
| | | | - K Subedi
- Institute for Research on Equity and Community Health (iREACH), ChristianaCare, Newark, DE, USA
| | - T Rahman
- Nemours Biomedical Research, Nemours Children's Health, Wilmington, DE, USA
| | - T H Shaffer
- Department of Pediatrics, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
- Department of Physiology, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
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3
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Sett A, Rogerson SR, Foo GWC, Keene J, Thomas N, Kee PPL, Zayegh A, Donath SM, Tingay DG, Davis PG, Manley BJ. Estimating Preterm Lung Volume: A Comparison of Lung Ultrasound, Chest Radiography, and Oxygenation. J Pediatr 2023; 259:113437. [PMID: 37088185 DOI: 10.1016/j.jpeds.2023.113437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/25/2023] [Accepted: 03/31/2023] [Indexed: 04/25/2023]
Abstract
OBJECTIVE To determine the relationship between lung ultrasound (LUS) examination, chest radiograph (CXR), and radiographic and clinical evaluations in the assessment of lung volume in preterm infants. STUDY DESIGN In this prospective cohort study LUS was performed before CXR on 70 preterm infants and graded using (1) a LUS score, (2) an atelectasis score, and (3) measurement of atelectasis depth. Radiographic diaphragm position and radio-opacification were used to determine global and regional radiographic atelectasis. The relationship between LUS, CXR, and oxygenation was assessed using receiver operator characteristic and correlation analysis. RESULTS LUS scores, atelectasis scores, and atelectasis depth did not correspond with radiographic global atelectasis (area under receiver operator characteristics curves, 0.54 [95% CI, 0.36-0.71], 0.49 [95% CI, 0.34-0.64], and 0.47 [95% CI, 0.31-0.64], respectively). Radiographic atelectasis of the right upper, right lower, left upper, and left lower quadrants was predicted by LUS scores (0.75 [95% CI, 0.59-0.92], 0.75 [95% CI, 0.62-0.89], 0.69 [95% CI, 0.56-0.82], and 0.63 [95% CI, 0.508-0.751]) and atelectasis depth (0.66 [95% CI, 0.54-0.78], 0.65 [95% CI, 0.53-0.77], 0.63 [95% CI, 0.50-0.76], and 0.56 [95% CI, 0.44-0.70]). LUS findings were moderately correlated with oxygen saturation index (ρ = 0.52 [95% CI, 0.30-0.70]) and saturation to fraction of inspired oxygen ratio (ρ = -0.63 [95% CI, -0.76 to -0.46]). The correlation between radiographic diaphragm position, the oxygenation saturation index, and peripheral oxygen saturation to fraction of inspired oxygen ratio was very weak (ρ = 0.36 [95% CI, 0.11-0.59] and ρ = -0.32 [95% CI, -0.53 to -0.07], respectively). CONCLUSIONS LUS assessment of lung volume does not correspond with radiographic diaphragm position preterm infants. However, LUS predicted radiographic regional atelectasis and correlated with oxygenation. The relationship between radiographic diaphragm position and oxygenation was very weak. Although LUS may not replace all radiographic measures of lung volume, LUS more accurately reflects respiratory status in preterm infants. TRIAL REGISTRATION Australian New Zealand Clinical Trials Registry: ACTRN12621001119886.
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Affiliation(s)
- Arun Sett
- Newborn Research Centre, The Royal Women's Hospital, Melbourne, Australia; Murdoch Children's Research Institute, Victoria, Australia; Joan Kirner Women's and Children's, Sunshine Hospital, Western Health, Melbourne, Australia; Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia; Paediatric Infant Perinatal Emergency Retrieval, The Royal Children's Hospital, Melbourne, Australia.
| | - Sheryle R Rogerson
- Newborn Research Centre, The Royal Women's Hospital, Melbourne, Australia; Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia; Paediatric Infant Perinatal Emergency Retrieval, The Royal Children's Hospital, Melbourne, Australia
| | - Gillian W C Foo
- Newborn Research Centre, The Royal Women's Hospital, Melbourne, Australia; Joan Kirner Women's and Children's, Sunshine Hospital, Western Health, Melbourne, Australia
| | - Jacqui Keene
- Department of Radiology, The Royal Women's Hospital, Melbourne, Australia
| | - Niranjan Thomas
- Joan Kirner Women's and Children's, Sunshine Hospital, Western Health, Melbourne, Australia; Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia
| | - Penny P L Kee
- Joan Kirner Women's and Children's, Sunshine Hospital, Western Health, Melbourne, Australia; Paediatric Infant Perinatal Emergency Retrieval, The Royal Children's Hospital, Melbourne, Australia
| | - Amir Zayegh
- Newborn Research Centre, The Royal Women's Hospital, Melbourne, Australia; Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia
| | - Susan M Donath
- Murdoch Children's Research Institute, Victoria, Australia
| | - David G Tingay
- Murdoch Children's Research Institute, Victoria, Australia; Department of Paediatrics, University of Melbourne, Melbourne, Australia; Department of Neonatology, Royal Children's Hospital, Melbourne, Australia
| | - Peter G Davis
- Newborn Research Centre, The Royal Women's Hospital, Melbourne, Australia; Murdoch Children's Research Institute, Victoria, Australia; Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia
| | - Brett J Manley
- Newborn Research Centre, The Royal Women's Hospital, Melbourne, Australia; Murdoch Children's Research Institute, Victoria, Australia; Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia
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4
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Sett A, Kenna KR, Sutton RJ, Perkins EJ, Sourial M, Chapman JD, Donath SM, Sasi A, Rogerson SR, Manley BJ, Davis PG, Pereira-Fantini PM, Tingay DG. Lung ultrasound of the dependent lung detects real-time changes in lung volume in the preterm lamb. Arch Dis Child Fetal Neonatal Ed 2023; 108:51-56. [PMID: 35750468 PMCID: PMC9763221 DOI: 10.1136/archdischild-2022-323900] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 06/03/2022] [Indexed: 12/28/2022]
Abstract
BACKGROUND Effective lung protective ventilation requires reliable, real-time estimation of lung volume at the bedside. Neonatal clinicians lack a readily available imaging tool for this purpose. OBJECTIVE To determine the ability of lung ultrasound (LUS) of the dependent region to detect real-time changes in lung volume, identify opening and closing pressures of the lung, and detect pulmonary hysteresis. METHODS LUS was performed on preterm lambs (n=20) during in vivo mapping of the pressure-volume relationship of the respiratory system using the super-syringe method. Electrical impedance tomography was used to derive regional lung volumes. Images were blindly graded using an expanded scoring system. The scores were compared with total and regional lung volumes, and differences in LUS scores between pressure increments were calculated. RESULTS Changes in LUS scores correlated moderately with changes in total lung volume (r=0.56, 95% CI 0.47-0.64, p<0.0001) and fairly with right whole (r=0.41, CI 0.30-0.51, p<0.0001), ventral (r=0.39, CI 0.28-0.49, p<0.0001), central (r=0.41, CI 0.31-0.52, p<0.0001) and dorsal (r=0.38, CI 0.27-0.49, p<0.0001) regional lung volumes. The pressure-volume relationship of the lung exhibited hysteresis in all lambs. LUS was able to detect hysteresis in 17 (85%) lambs. The greatest changes in LUS scores occurred at the opening and closing pressures. CONCLUSION LUS was able to detect large changes in total and regional lung volume in real time and correctly identified opening and closing pressures but lacked the precision to detect small changes in lung volume. Further work is needed to improve precision prior to translation to clinical practice.
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Affiliation(s)
- Arun Sett
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia .,Newborn Research Centre, The Royal Women's Hospital, Melbourne, Victoria, Australia.,Newborn Services, Joan Kirner Women's and Children's, Sunshine Hospital, Western Health, Melbourne, Victoria, Australia.,Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia.,Paediatric Infant Perinatal Emergency Retrieval, The Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Kelly R Kenna
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Rebecca J Sutton
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia,Translational Research Unit, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Elizabeth J Perkins
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Magdy Sourial
- Translational Research Unit, Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Jack D Chapman
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Susan M Donath
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Arun Sasi
- Paediatric Infant Perinatal Emergency Retrieval, The Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Sheryle R Rogerson
- Newborn Research Centre, The Royal Women's Hospital, Melbourne, Victoria, Australia,Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia,Paediatric Infant Perinatal Emergency Retrieval, The Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Brett J Manley
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia,Newborn Research Centre, The Royal Women's Hospital, Melbourne, Victoria, Australia,Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
| | - Peter G Davis
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia,Newborn Research Centre, The Royal Women's Hospital, Melbourne, Victoria, Australia,Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
| | - Prue M Pereira-Fantini
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - David G Tingay
- Neonatal Research, Murdoch Children's Research Institute, Melbourne, Victoria, Australia,Newborn Research Centre, The Royal Women's Hospital, Melbourne, Victoria, Australia,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia,Department of Neonatology, The Royal Children's Hospital, Melbourne, Victoria, Australia
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5
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Pacheco A, Jayet B, Svanberg EK, Dehghani H, Dempsey E, Andersson-Engels S. Numerical investigation of the influence of the source and detector position for optical measurement of lung volume and oxygen content in preterm infants. JOURNAL OF BIOPHOTONICS 2022; 15:e202200041. [PMID: 35340113 DOI: 10.1002/jbio.202200041] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/23/2022] [Accepted: 03/25/2022] [Indexed: 06/14/2023]
Abstract
There is an urgent need for improved respiratory surveillance of preterm infants. Gas in scattering media absorption spectroscopy (GASMAS) is emerging as a potential clinical cutaneous monitoring tool of lung functions in neonates. A challenge in the clinical translation of GASMAS is to obtain sufficiently high signal-to-noise ratios in the measurements, since the light attenuation is high in human tissue. Previous GASMAS studies on piglets have shown higher signal quality with an internal source, as more light propagates through the lung and the loss due to scattering and absorption is less. In this article we simulated light propagation with an intratracheal and a dermal source, and investigated the signal quality and lung volume probed. The results suggest that GASMAS has the potential to measure respiratory volumes; and the sensitivity is higher for an intratracheal source which also enables to probe most of the lung.
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Affiliation(s)
- Andrea Pacheco
- Biophotonics@Tyndall, IPIC, Tyndall National Institute, Cork, Ireland
- Department of Physics, University College Cork, Cork, Ireland
| | - Baptiste Jayet
- Biophotonics@Tyndall, IPIC, Tyndall National Institute, Cork, Ireland
| | - Emilie Krite Svanberg
- Department of Clinical Sciences, Paediatric Anaesthesiology and Intensive Care Medicine, Skåne University Hospital, Lund University, Lund, Sweden
| | - Hamid Dehghani
- School of Computer Science, the University of Birmingham, Birmingham
| | - Eugene Dempsey
- INFANT Centre, Cork University Maternity Hospital, University College Cork, Ireland
| | - Stefan Andersson-Engels
- Biophotonics@Tyndall, IPIC, Tyndall National Institute, Cork, Ireland
- Department of Physics, University College Cork, Cork, Ireland
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Landolfo F, De Rose DU, Columbo C, Valfrè L, Massolo AC, Braguglia A, Capolupo I, Bagolan P, Dotta A, Morini F. Growth and morbidity in infants with Congenital Diaphragmatic Hernia according to initial lung volume: A pilot study. J Pediatr Surg 2022; 57:643-648. [PMID: 34281708 DOI: 10.1016/j.jpedsurg.2021.06.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 06/22/2021] [Accepted: 06/26/2021] [Indexed: 11/28/2022]
Abstract
Background In congenital diaphragmatic hernia (CDH) survivors, failure to thrive is a well-known complication, ascribed to several factors. The impact of lung volume on growth of CDH survivors is poorly explored. Our aim was to evaluate if, in CDH survivors, lung volume (LV) after extubation correlates with growth at 12 and 24 months of life. Methods LV (measured as functional residual capacity-FRC) was evaluated by multibreath washout traces with an ultrasonic flowmeter and helium gas dilution technique, shortly after extubation. All CDH survivors are enrolled in a dedicated follow-up program. For the purpose of this study, we analyzed the correlation between FRC obtained shortly after extubation and anthropometric measurements at 12 and 24 months of age. We also compared growth between infants with normal lungs and those with hypoplasic lungs according to FRC values. A p < 0.05 was considered as statistically significant. Results We included in the study 22 CDH survivors who had FRC analyzed after extubation and auxological follow-up at 12 and 24 months of age. We found a significant correlation between FRC and weight Z-score at 12 months, weight Z-score at 24 months and height Z-score at 24 months. We also demonstrated that CDH infants with hypoplasic lungs had a significantly lower weight at 12 months and at 24 months and a significantly lower height at 24 months, when compared to infants with normal lungs. Conclusion We analyzed the predictive value of bedside measured lung volumes in a homogeneous cohort of CDH infants and demonstrated a significant correlation between FRC and growth at 12 and 24 months of age. An earlier identification of patients that will require an aggressive nutritional support (such as those with pulmonary hypoplasia) may help reducing the burden of failure to thrive.
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Affiliation(s)
- Francesca Landolfo
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy
| | - Domenico Umberto De Rose
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy.
| | - Claudia Columbo
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy
| | - Laura Valfrè
- Neonatal Surgery Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Anna Claudia Massolo
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy
| | - Annabella Braguglia
- Neonatal Intermediate Care Unit and Follow-up, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Irma Capolupo
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy
| | - Pietro Bagolan
- Neonatal Surgery Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Andrea Dotta
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy
| | - Francesco Morini
- Neonatal Surgery Unit, Medical and Surgical Department of Fetus - Newborn - Infant, "Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
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7
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Development of Lung Function in Preterm Infants During the First Two Years of Life. Arch Bronconeumol 2022; 58:237-245. [PMID: 35312587 DOI: 10.1016/j.arbres.2021.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 06/23/2021] [Accepted: 07/18/2021] [Indexed: 11/22/2022]
Abstract
INTRODUCTION It remains unclear if prematurity itself can influence post delivery lung development and particularly, the bronchial size. AIM To assess lung function during the first two years of life in healthy preterm infants and compare the measurements to those obtained in healthy term infants during the same time period. METHODS This observational longitudinal study assessed lung function in 74 preterm (30+0 to 35+6 weeks' gestational age) and 76 healthy term control infants who were recruited between 2011 and 2013. Measurements of tidal breathing, passive respiratory mechanics, tidal and raised volume forced expirations (V'maxFRC and FEF25-75, respectively) were undertaken following administration of oral chloral hydrate sedation according to ATS/ERS recommendations at 6- and 18-months corrected age. RESULTS Lung function measurements were obtained from the preterm infants and full term controls initially at 6 months of age. Preterm infants had lower absolute and adjusted values (for gestational age, postnatal age, sex, body size, and confounding factors) for respiratory compliance and V'maxFRC. At 18 months corrected postnatal age, similar measurements were repeated in 57 preterm infants and 61 term controls. A catch-up in tidal volume, respiratory mechanics parameters, FEV0.5 and forced expiratory flows was seen in preterm infants. CONCLUSION When compared with term controls, the lower forced expiratory flows observed in the healthy preterm group at 6 months was no longer evident at 18 months corrected age, suggesting a catch-up growth of airway function.
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8
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Förster KM, Roth CJ, Hilgendorff A, Ertl-Wagner B, Flemmer AW, Wall WA. In silico numerical simulation of ventilator settings during high-frequency ventilation in preterm infants. Pediatr Pulmonol 2021; 56:3839-3846. [PMID: 34432956 DOI: 10.1002/ppul.25626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 08/01/2021] [Accepted: 08/04/2021] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Despite the routine use of antenatal steroids, exogenous surfactants, and different noninvasive ventilation methods, many extremely low gestational age neonates, preterm, and term infants eventually require invasive ventilation. In addition to prematurity, mechanical ventilation itself can induce ventilator-induced lung injury leading to lifelong pulmonary sequelae. Besides conventional mechanical ventilation, high-frequency oscillatory ventilation (HFOV) with tidal volumes below dead space and high ventilation frequencies is used either as a primary or rescue therapy in severe neonatal respiratory failure. METHODS AND RESULTS Applying a high-resolution computational lung modeling technique in a preterm infant, we studied three different high-frequency ventilation settings as well as conventional ventilation (CV) settings. Evaluating the computed oxygen delivery (OD) and lung mechanics (LM) we outline for the first time how changing ventilator settings from CV to HFOV lead to significant improvements in OD and LM. CONCLUSION This personalized "digital twin" strategy advances our general knowledge of protective ventilation strategies in neonatal care and can support decisions on various modes of ventilatory therapy at high frequencies.
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Affiliation(s)
- Kai M Förster
- Division of Neonatology, Dr. von Hauner Children's Hospital, LMU University Hospital Munich, Munich, Germany.,Institute for Lung Biology and Disease and Comprehensive Pneumology Center with the CPC-M bioArchive, Helmholtz Zentrum München, Germany
| | - Christian J Roth
- Institute for Computational Mechanics, Technical University of Munich, Garching, Germany
| | - Anne Hilgendorff
- Division of Neonatology, Dr. von Hauner Children's Hospital, LMU University Hospital Munich, Munich, Germany.,Institute for Lung Biology and Disease and Comprehensive Pneumology Center with the CPC-M bioArchive, Helmholtz Zentrum München, Germany.,Center for Comprehensive Developmental Care (CDeCLMU), LMU University Hospital Munich, Munich, 80337, Germany
| | - Birgit Ertl-Wagner
- Department of Radiology, LMU University Hospital Munich, Munich, Germany.,Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, Canada.,Department of Medical Imaging, University of Toronto, Toronto, Canada
| | - Andreas W Flemmer
- Division of Neonatology, Dr. von Hauner Children's Hospital, LMU University Hospital Munich, Munich, Germany
| | - Wolfgang A Wall
- Institute for Computational Mechanics, Technical University of Munich, Garching, Germany
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9
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Columbo C, Landolfo F, De Rose DU, Massolo AC, Secinaro A, Santangelo TP, Trozzi M, Campanale CM, Toscano A, Capolupo I, Bagolan P, Dotta A. The Role of Lung Function Testing in Newborn Infants With Congenital Thoracic Arterial Anomalies. Front Pediatr 2021; 9:682551. [PMID: 34211945 PMCID: PMC8239236 DOI: 10.3389/fped.2021.682551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/04/2021] [Indexed: 11/30/2022] Open
Abstract
Introduction: Congenital thoracic arterial anomalies (CTAAs), such as complete or incomplete vascular rings, pulmonary artery sling, and innominate artery compression syndrome, may cause severe tracheomalacia and upper airway obstruction. An obstructive ventilatory pattern at lung function testing (LFT) has been suggested in the presence of CTAA. The severity of obstruction may be evaluated by LFT. Little is known about the use of LFT in newborn infants with CTAA. The aim of our study is to evaluate the role of LFT in CTAA diagnosis. Methods: This is a retrospective study, conducted between February 2016 and July 2020. All CTAA cases for whom LFT was performed preoperatively were considered for inclusion. Tidal volume (Vt), respiratory rate, and the ratio of time to reach the peak tidal expiratory flow over total expiratory time (tPTEF/tE) were assessed and compared to existing normative data. Demographics and CTAA characteristics were also collected. Results: Thirty cases were included. All infants with CTAA showed a significantly reduced Vt and tPTEF/tE, compared to existing normative data suggesting an obstructive pattern. No significant differences were found for LFT between cases with a tracheal obstruction <50% compared to those with tracheal obstruction ≥50%, or between cases with and without symptoms. Sixteen infants (53.3%) had respiratory symptoms related to CTAA. Of these, only two cases had also dysphagia. Conclusion: LFT values were significantly reduced in cases with CTAA before surgery. LFT represents a potential feasible and non-invasive useful tool to guide diagnosis in the suspect of CTAA.
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Affiliation(s)
- Claudia Columbo
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Francesca Landolfo
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Domenico Umberto De Rose
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Anna Claudia Massolo
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Aurelio Secinaro
- Advanced Cardiovascular Imaging Unit, Department of Imaging-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Teresa Pia Santangelo
- Advanced Cardiovascular Imaging Unit, Department of Imaging-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Marilena Trozzi
- Airway Surgery Unit, "Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Cosimo Marco Campanale
- Perinatal Cardiology Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Alessandra Toscano
- Perinatal Cardiology Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Irma Capolupo
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Pietro Bagolan
- Newborn Surgery Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
| | - Andrea Dotta
- Neonatal Intensive Care Unit, Medical and Surgical Department of Fetus, Newborn and Infant-"Bambino Gesù" Children's Hospital IRCCS, Rome, Italy
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10
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Guerra S, Lombardi E, Stern DA, Sherrill DL, Gilbertson-Dahdal D, Wheatley-Guy CM, Snyder EM, Wright AL, Martinez FD, Morgan WJ. Fetal Origins of Asthma: A Longitudinal Study from Birth to Age 36 Years. Am J Respir Crit Care Med 2020; 202:1646-1655. [PMID: 32649838 PMCID: PMC7737573 DOI: 10.1164/rccm.202001-0194oc] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 07/10/2020] [Indexed: 11/16/2022] Open
Abstract
Rationale: Deficits in infant lung function-including the ratio of the time to reach peak tidal expiratory flow to the total expiratory time (tptef/te) and maximal expiratory flow at FRC (V̇maxFRC)-have been linked to increased risk for childhood asthma.Objectives: To examine the individual and combined effects of tptef/te and V̇maxFRC in infancy on risk for asthma and abnormalities of airway structure into mid-adult life.Methods: One hundred eighty participants in the Tucson Children's Respiratory Study birth cohort had lung function measured by the chest-compression technique in infancy (mean age ± SD: 2.0 ± 1.2 mo). Active asthma was assessed in up to 12 questionnaires between ages 6 and 36 years. Spirometry and chest high-resolution computed tomographic (HRCT) imaging were completed in a subset of participants at age 26. The relations of infant tptef/te and V̇maxFRC to active asthma and airway structural abnormalities into adult life were tested in multivariable mixed models.Measurements and Main Results: After adjustment for covariates, a 1-SD decrease in infant tptef/te and V̇maxFRC was associated with a 70% (P = 0.001) and 55% (P = 0.005) increased risk of active asthma, respectively. These effects were partly independent, and two out of three infants who were in the lowest tertile for both tptef/te and V̇maxFRC developed active asthma by mid-adult life. Infant V̇maxFRC predicted reduced airflow and infant tptef/te reduced HRCT airway caliber at age 26.Conclusions: These findings underscore the long-lasting effects of the fetal origins of asthma, support independent contributions by infant tptef/te and V̇maxFRC to development of asthma, and link deficits at birth in tptef/te with HRCT-assessed structural airway abnormalities in adult life.
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Affiliation(s)
- Stefano Guerra
- Asthma and Airway Disease Research Center
- Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, College of Medicine – Tucson
- Mel and Enid Zuckerman College of Public Health
| | - Enrico Lombardi
- Asthma and Airway Disease Research Center
- Department of Medical Imaging, College of Medicine – Tucson, and
| | | | - Duane L. Sherrill
- Asthma and Airway Disease Research Center
- Department of Pediatrics, University of Arizona, Tucson, Arizona
| | | | | | - Eric M. Snyder
- Department of Cardiovascular Diseases, Mayo Clinic, Scottsdale, Arizona; and
| | | | | | - Wayne J. Morgan
- Asthma and Airway Disease Research Center
- Geneticure, Rochester, Minnesota
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11
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Ring AM, Carlens J, Bush A, Castillo-Corullón S, Fasola S, Gaboli MP, Griese M, Koucky V, La Grutta S, Lombardi E, Proesmans M, Schwerk N, Snijders D, Nielsen KG, Buchvald F. Pulmonary function testing in children's interstitial lung disease. Eur Respir Rev 2020; 29:29/157/200019. [PMID: 32699025 DOI: 10.1183/16000617.0019-2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 04/11/2020] [Indexed: 12/17/2022] Open
Abstract
The use of pulmonary function tests (PFTs) has been widely described in airway diseases like asthma and cystic fibrosis, but for children's interstitial lung disease (chILD), which encompasses a broad spectrum of pathologies, the usefulness of PFTs is still undetermined, despite widespread use in adult interstitial lung disease. A literature review was initiated by the COST/Enter chILD working group aiming to describe published studies, to identify gaps in knowledge and to propose future research goals in regard to spirometry, whole-body plethysmography, infant and pre-school PFTs, measurement of diffusing capacity, multiple breath washout and cardiopulmonary exercise tests in chILD. The search revealed a limited number of papers published in the past three decades, of which the majority were descriptive and did not report pulmonary function as the main outcome.PFTs may be useful in different stages of management of children with suspected or confirmed chILD, but the chILD spectrum is diverse and includes a heterogeneous patient group in all ages. Research studies in well-defined patient cohorts are needed to establish which PFT and outcomes are most relevant for diagnosis, evaluation of disease severity and course, and monitoring individual conditions both for improvement in clinical care and as end-points in future randomised controlled trials.
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Affiliation(s)
- Astrid Madsen Ring
- Paediatric Pulmonary Service, Dept of Paediatrics and Adolescent Medicine, Copenhagen University Hospital, Rigshospitalet, Danish PCD & chILD Centre, CF Centre Copenhagen, Copenhagen, Denmark.,Joint first authors
| | - Julia Carlens
- Clinic for Paediatric Pneumology, Allergology and Neonatology, Medizinische Hochschule Hannover Zentrum fur Kinderheilkunde und Jugendmedizin, Hannover, Germany.,Joint first authors
| | - Andy Bush
- Paediatrics and Paediatric Respiratory Medicine, Imperial College London, London, UK.,Paediatric Respiratory Medicine, Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - Silvia Castillo-Corullón
- Unidad de Neumología infantil y Fibrosis quística, Hospital Clínico Universitario de Valencia, Valencia, Spain
| | - Salvatore Fasola
- Institute of Biomedical Research and Innovation, National Research Council of Italy, Palermo, Italy
| | - Mirella Piera Gaboli
- Neumologia Infantil y Unidad de Cuidados Intensivos Pediatricos, Hospital Universitario Salamanca, Salamanca, Spain
| | - Matthias Griese
- University Hospital of Munich, Dr. von Hauner Children's Hospital, German Center for Lung Research (DZL), Munich, Germany
| | - Vaclav Koucky
- Dept of Paediatrics, Univerzita Karlova v Praze 2 lekarska fakulta, Prague, Czech Republic
| | - Stefania La Grutta
- Institute of Biomedical Research and Innovation, National Research Council of Italy, Palermo, Italy
| | - Enrico Lombardi
- Pediatric Pulmonary Unit, Anna Meyer Pediatric University-Hospital, Florence, Italy
| | | | - Nicolaus Schwerk
- Clinic for Paediatric Pneumology, Allergology and Neonatology, Medizinische Hochschule Hannover Zentrum fur Kinderheilkunde und Jugendmedizin, Hannover, Germany
| | | | - Kim Gjerum Nielsen
- Paediatric Pulmonary Service, Dept of Paediatrics and Adolescent Medicine, Copenhagen University Hospital, Rigshospitalet, Danish PCD & chILD Centre, CF Centre Copenhagen, Copenhagen, Denmark.,Joint last authors
| | - Frederik Buchvald
- Paediatric Pulmonary Service, Dept of Paediatrics and Adolescent Medicine, Copenhagen University Hospital, Rigshospitalet, Danish PCD & chILD Centre, CF Centre Copenhagen, Copenhagen, Denmark .,Joint last authors
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12
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Yoder LM, Higano NS, Schapiro AH, Fleck RJ, Hysinger EB, Bates AJ, Kingma PS, Merhar SL, Fain SB, Woods JC. Elevated lung volumes in neonates with bronchopulmonary dysplasia measured via MRI. Pediatr Pulmonol 2019; 54:1311-1318. [PMID: 31134768 DOI: 10.1002/ppul.24378] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 03/11/2019] [Accepted: 05/01/2019] [Indexed: 01/31/2023]
Abstract
BACKGROUND Bronchopulmonary dysplasia (BPD) is a chronic lung disease of prematurity defined by requirement for respiratory support at 36 weeks postmenstrual age (PMA), but structural sequelae like lung hyperinflation are often not quantified. Quiet-breathing, nonsedated magnetic resonance imaging (MRI) allows tomographic quantification of lung volumes and densities. We hypothesized that functional residual capacity (FRC) and intrapleural volume (IV) are increased in BPD and correlate with qualitative radiological scoring of hyperinflation. METHODS Ultrashort echo time (UTE) MRI of 17 neonates (acquired at ~39 weeks PMA) were reconstructed at end-expiration and end-inspiration via the time course of the k0 point in k-space. Images were segmented to determine total lung, tidal, parenchymal tissue, and vascular tissue volumes. FRC was calculated by subtracting parenchymal and vascular tissue volumes from IV. Respiratory rate (RR) was calculated via the UTE respiratory waveform, yielding estimates of minute ventilation when combined with tidal volumes (TVs). Two radiologists scored hyperinflation on the MR images. RESULTS IV at FRC increased in BPD: for control, mild, and severe (patients the median volumes were 32.8, 33.5, and 50.9 mL/kg, respectively. TV (medians: 2.21, 3.64, and 4.84 mL/kg) and minute ventilation (medians: 493, 750, and 991 mL/min) increased with increasing severity of BPD (despite decreasing RR, medians: 75.6, 63.0, and 56.1 breaths/min). FRC increased with increasing severity of BPD (39.3, 38.3, and 56.0 mL, respectively). Findings were consistent with increased hyperinflation scored by radiologists. CONCLUSIONS This study demonstrates that UTE MRI can quantify hyperinflation in neonatal BPD and that lung volumes significantly increase with disease severity.
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Affiliation(s)
- Lauren M Yoder
- University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Nara S Higano
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Andrew H Schapiro
- Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, Ohio.,Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Robert J Fleck
- Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, Ohio.,Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Erik B Hysinger
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Alister J Bates
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, Ohio.,Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Paul S Kingma
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Stephanie L Merhar
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Sean B Fain
- Division of Neonatology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Department of Medical Physics, University of Wisconsin, Madison, Wisconsin.,Department of Radiology, University of Wisconsin, Madison, Wisconsin
| | - Jason C Woods
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, Ohio.,Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
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13
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Urs R, Kotecha S, Hall GL, Simpson SJ. Persistent and progressive long-term lung disease in survivors of preterm birth. Paediatr Respir Rev 2018; 28:87-94. [PMID: 29752125 DOI: 10.1016/j.prrv.2018.04.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 04/09/2018] [Indexed: 02/05/2023]
Abstract
Preterm birth accounts for approximately 11% of births globally, with rates increasing across many countries. Concurrent advances in neonatal care have led to increased survival of infants of lower gestational age (GA). However, infants born <32 weeks of GA experience adverse respiratory outcomes, manifesting with increased respiratory symptoms, hospitalisation and health care utilisation into early childhood. The development of bronchopulmonary dysplasia (BPD) - the chronic lung disease of prematurity - further increases the risk of poor respiratory outcomes throughout childhood, into adolescence and adulthood. Indeed, survivors of preterm birth have shown increased respiratory symptoms, altered lung structure, persistent and even declining lung function throughout childhood. The mechanisms behind this persistent and sometimes progressive lung disease are unclear, and the implications place those born preterm at increased risk of respiratory morbidity into adulthood. This review aims to summarise what is known about the long-term pulmonary outcomes of contemporary preterm birth, examine the possible mechanisms of long-term respiratory morbidity in those born preterm and discuss addressing the unknowns and potentials for targeted treatments.
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Affiliation(s)
- Rhea Urs
- Telethon Kids Institute, Perth, Australia; School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Australia
| | - Sailesh Kotecha
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, UK
| | - Graham L Hall
- Telethon Kids Institute, Perth, Australia; School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Australia
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14
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Roth CJ, Förster KM, Hilgendorff A, Ertl-Wagner B, Wall WA, Flemmer AW. Gas exchange mechanisms in preterm infants on HFOV - a computational approach. Sci Rep 2018; 8:13008. [PMID: 30158557 PMCID: PMC6115430 DOI: 10.1038/s41598-018-30830-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 07/19/2018] [Indexed: 11/25/2022] Open
Abstract
High-frequency oscillatory ventilation (HFOV) is a commonly used therapy applied to neonates requiring ventilatory support during their first weeks of life. Despite its wide application, the underlying gas exchange mechanisms promoting the success of HVOF in neonatal care are not fully understood until today. In this work, a highly resolved computational lung model, derived from Magnetic Resonance Imaging (MRI) and Infant Lung Function Testing (ILFT), is used to reveal the reason for highly efficient gas exchange during HFOV, in the preterm infant. In total we detected six mechanisms that facilitate gas exchange during HFOV: (i) turbulent vortices in large airways; (ii) asymmetric in- and expiratory flow profiles; (iii) radial mixing in main bronchi; (iv) laminar flow in higher generations of the respiratory tract; (v) pendelluft; (vi) direct ventilation of central alveoli. The illustration of six specific gas transport phenomena during HFOV in preterm infants advances general knowledge on protective ventilation in neonatal care and can support decisions on various modes of ventilatory therapy at high frequencies.
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Affiliation(s)
- Christian J Roth
- Institute for Computational Mechanics, Technical University of Munich, 85748, Garching, Germany
| | - Kai M Förster
- Division of Neonatology, Dr. von Hauner Children's Hospital, Perinatal Center Grosshadern, LMU-Munich, 81337, Munich, Germany
- Comprehensive Pneumology Center, Helmholtz Zentrum München, Munich, Germany, Member of the German Lung Research Center (DZL), Munich, Germany
| | - Anne Hilgendorff
- Division of Neonatology, Dr. von Hauner Children's Hospital, Perinatal Center Grosshadern, LMU-Munich, 81337, Munich, Germany
- Comprehensive Pneumology Center, Helmholtz Zentrum München, Munich, Germany, Member of the German Lung Research Center (DZL), Munich, Germany
| | | | - Wolfgang A Wall
- Institute for Computational Mechanics, Technical University of Munich, 85748, Garching, Germany
| | - Andreas W Flemmer
- Division of Neonatology, Dr. von Hauner Children's Hospital, Perinatal Center Grosshadern, LMU-Munich, 81337, Munich, Germany.
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15
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Kaczmarczyk K, Wiszomirska I, Szturmowicz M, Magiera A, Błażkiewicz M. Are preterm-born survivors at risk of long-term respiratory disease? Ther Adv Respir Dis 2017; 11:277-287. [PMID: 28614994 PMCID: PMC5933633 DOI: 10.1177/1753465817710595] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 04/21/2017] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND To evaluate the long-term impact of preterm birth on respiratory function in female patients born preterm, we undertook spirometric examinations twice, as they reached the age of puberty, then follow-up examinations of part of the same cohort in adulthood. We sought evidence that preterm birth is correlated with poorer spirometric results into adulthood. METHODS A total of 70 girls (aged 12.2 ± 1.5 years in 1997) who had been born preterm (at 34.7 ± 1.86 weeks, none having experienced bronchopulmonary dysplasia) took part in spriometric examinations in 1997 and again in 1998. Of those, after a gap of 17 years, a group of 12 were successfully recontacted and participated in the 2015 examination as adults (then aged 27.6 ± 2.6 years, born at 34.5 ± 1.92 weeks). We compared spirometric results across the adolescent and adult examinations, and compared the adult results with an adult reference group. RESULTS The percentage values of FEV1 (forced expiratory volume in 1 s), FVC (forced vital capacity) and MVV (maximal voluntary ventilation) showed significant improvement between the two examinations in the early adolescent period. In adulthood, FEV1%pred (percentage predicted forced expiratory volume in 1 s) showed no statistically significant difference. The mean values of both FVC and FVC%pred (percentage predicted forced vital capacity) for the preterm-born group were lower than for the reference group, but this was not statistically significant. The preterm-born group showed lower values of such parameters as forced expiratory flow at 25-75% of FVC, MEF25 (maximal expiratory flow at 25% of forced vital capacity) and FEV1/FVC as compared with the reference group, but again without statistical significance. CONCLUSIONS (1) A somewhat below-norm level of respiratory parameters among preterm-born girls entering pubescence may attest to continued negative impact on their respiratory system. (2) A significant improvement in their spirometric results 1 year later may indicate that pubescence helps compensate for the earlier negative effect of preterm birth. (3) No significant differences were seen in lung function in preterm-born adults as compared with a reference group of adults, although the preterm-born group did exhibit lower values of all parameters studied and more frequent obstructive disorders.
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Affiliation(s)
- Katarzyna Kaczmarczyk
- Head of Physiology Department, Faculty of
Rehabilitation, Józef Piłsudski University of Physical Education in Warsaw,
Marymoncka 34 Street, Warsaw, Poland
| | - Ida Wiszomirska
- Józef Piłsudski University of Physical Education
in Warsaw, Faculty of Rehabilitation, Warsaw, Poland
| | - Magdalena Szturmowicz
- Józef Piłsudski University of Physical Education
in Warsaw, Faculty of Rehabilitation, Warsaw, Poland
| | - Andrzej Magiera
- Józef Piłsudski University of Physical Education
in Warsaw, Faculty of Rehabilitation, Warsaw, Poland
| | - Michalina Błażkiewicz
- Józef Piłsudski University of Physical Education
in Warsaw, Faculty of Rehabilitation, Warsaw, Poland
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16
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Jiang G, Li A, Wang L, Qian L, Cao Y, Huang J, Wan C, Zhang X. Reference data for BabyBody-plethysmographic measurements in Chinese neonates and infants. Respirology 2017. [PMID: 28621890 DOI: 10.1111/resp.13104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gaoli Jiang
- Department of Respirology; Children's Hospital of Fudan University; Shanghai China
| | - Albert Li
- Department of Peadiatrics, Faculty of Medicine; The Chinese University of Hong Kong; Hong Kong China
| | - Libo Wang
- Department of Respirology; Children's Hospital of Fudan University; Shanghai China
| | - Liling Qian
- Department of Respirology; Children's Hospital of Fudan University; Shanghai China
| | - Yun Cao
- Department of Neonatology; Children's Hospital of Fudan University; Shanghai China
| | - Jianfeng Huang
- Department of Respirology; Children's Hospital of Fudan University; Shanghai China
| | - Chengzhou Wan
- Department of Pulmonary Function Laboratory; Children's Hospital of Fudan University; Shanghai China
| | - Xiaobo Zhang
- Department of Respirology; Children's Hospital of Fudan University; Shanghai China
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17
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Functional residual capacity and lung clearance index in infants treated for esophageal atresia and tracheoesophageal fistula. J Pediatr Surg 2016; 51:559-62. [PMID: 26607967 DOI: 10.1016/j.jpedsurg.2015.10.050] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 09/28/2015] [Accepted: 10/14/2015] [Indexed: 11/21/2022]
Abstract
BACKGROUND Newborn babies with esophageal atresia/tracheoesophageal fistula (EA/TEF) are prone to respiratory tract disorders. Functional residual capacity (FRC) and lung clearance index (LCI) are commonly considered useful and sensitive tools to investigate lung function and early detecting airways diseases. The aim of the present study is to report the first series of EA/TEF infants prospectively evaluated for FRC and LCI. METHODS Prospective observational cohort study of all patients treated for EA/TEF. Lung volume and ventilation inhomogeneity were measured by helium gas dilution technique using an ultrasonic flow meter. Babies were studied both in assisted controlled ventilation (sedated) and in spontaneous breathing (quiet sleep). Three consecutive FRC and LCI measurements were collected for each test at three different time points: before surgery (T0), 24hours after surgery (T1) and after extubation (T2). RESULTS 16 EA newborns were eligible for the study between December 2011 and July 2013. Three were excluded because of technical problems. At T0 FRC values were in the normal range regardless the presence of TEF but worsened afterwards at T1, with a subsequent recovering after extubation; a significant improvement after surgery was observed concerning LCI while no differences were found in tidal volume. CONCLUSION Helium gas dilution technique is a suitable method to measure the effect of surgery on lung physiology, even in ventilated infants with EA. The changes observed could be related to the ventilatory management and lung compression during surgical procedure.
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18
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Pérez-Yarza EG, Moreno-Galdó A, Ramilo O, Rubí T, Escribano A, Torres A, Sardón O, Oliva C, Pérez G, Cortell I, Rovira-Amigo S, Pastor-Vivero MD, Pérez-Frías J, Velasco V, Torres-Borrego J, Figuerola J, Barrio MI, García-Hernández G, Mejías A. Risk factors for bronchiolitis, recurrent wheezing, and related hospitalization in preterm infants during the first year of life. Pediatr Allergy Immunol 2015; 26:797-804. [PMID: 26031206 DOI: 10.1111/pai.12414] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/23/2015] [Indexed: 11/25/2022]
Abstract
BACKGROUND Airway diseases are highly prevalent in infants and cause significant morbidity. We aimed to determine the incidence and risk factors for respiratory morbidity in a Spanish cohort of moderate-to-late preterm (MLP) infants prospectively followed during their first year of life. METHODS SAREPREM is a multicenter, prospective, longitudinal study. Preterm infants born at 32-35 weeks of gestation with no comorbidities were enrolled within 2 weeks of life and followed at 2-4 weeks, 6, and 12 months of age. Multivariate mixed-models were performed to identify independent risk factors associated with (i) development of bronchiolitis, (ii) recurrent wheezing, or (iii) related hospital admissions. RESULTS Overall, 977 preterm infants were included, and 766 (78.4%) completed follow-up. Of those, 365 (47.7%) developed bronchiolitis during the first year, 144 (18.8%) recurrent wheezing, and 48 (6.3%) were hospitalized. While low birthweight, day care attendance (DCA) and school-age siblings were significantly and independently associated with both the development of bronchiolitis and recurrent wheezing, lower maternal age increased the risk for bronchiolitis and respiratory-related hospitalizations. Lastly, mechanical ventilation was associated with a higher risk of bronchiolitis and history of asthma in any parent increased the likelihood of developing recurrent wheezing. CONCLUSIONS In this study, several non-modifiable parameters (family history of asthma, low birthweight, need for mechanical ventilation) and modifiable parameters (young maternal age, DCA, or exposure to school-age siblings) were identified as significant risk factors for the development of bronchiolitis and recurrent wheezing during the first year of life in MLP infants.
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Affiliation(s)
- Eduardo G Pérez-Yarza
- Division of Pediatric Respiratory Medicine, Hospital Universitario Donostia-Instituto Biodonostia, San Sebastián, Spain.,Biomedical Research Centre Network for Respiratory Diseases (CIBERES), San Sebastián, Spain.,Department of Pediatrics, University of the Basque Country (UPV/EHU), San Sebastián, Spain
| | - Antonio Moreno-Galdó
- Pediatric Pulmonary Unit, Department of Pediatrics, Obstetrics, Gynecology and Preventive Medicine, Hospital Universitario Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Octavio Ramilo
- Division of Infectious Diseases, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University, Columbus, OH, USA
| | - Teresa Rubí
- Pediatric Pulmonary Section, Hospital Torrecárdenas, Almería, Spain
| | - Amparo Escribano
- Pediatric Pulmonary Unit, Hospital Clínico Universitario, Universidad de Valencia, Valencia, Spain
| | - Antonio Torres
- Department of Pediatrics, Hospital San Juan de la Cruz, Úbeda, Spain
| | - Olaia Sardón
- Division of Pediatric Respiratory Medicine, Hospital Universitario Donostia-Instituto Biodonostia, San Sebastián, Spain.,Department of Pediatrics, University of the Basque Country (UPV/EHU), San Sebastián, Spain
| | - Concepción Oliva
- Pediatric Pulmonary Unit, Hospital Universitario Nuestra Señora de la Candelaria, Tenerife, Spain
| | - Guadalupe Pérez
- Pediatric Pulmonary Section, Hospital Universitario Virgen Macarena, Universidad de Sevilla, Sevilla, Spain
| | - Isidoro Cortell
- Pediatric Pulmonary Section, Hospital Universitario La Fe, Valencia, Spain
| | - Sandra Rovira-Amigo
- Pediatric Pulmonary Unit, Department of Pediatrics, Obstetrics, Gynecology and Preventive Medicine, Hospital Universitario Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Maria D Pastor-Vivero
- Pediatric Pulmonary Section, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, Murcia, Spain
| | | | - Valle Velasco
- Pediatric Pulmonary Unit, Hospital Clínico Universitario, Tenerife, Spain
| | | | - Joan Figuerola
- Pediatric Pulmonary Section, Hospital Universitario Son Espases, Palma de Mallorca, Spain
| | | | | | - Asunción Mejías
- Division of Infectious Diseases, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University, Columbus, OH, USA
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19
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Chen HL, Yang RC, Lee WT, Lee PL, Hsu JH, Wu JR, Dai ZK. Lung function in very preterm infants with patent ductus arteriosus under conservative management: an observational study. BMC Pediatr 2015; 15:167. [PMID: 26496854 PMCID: PMC4620001 DOI: 10.1186/s12887-015-0480-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 10/08/2015] [Indexed: 11/25/2022] Open
Abstract
Background Persistent patent ductus arteriosus (PDA) during hospitalization is thought to be associated with adverse pulmonary outcomes in very preterm infants. This observational study aimed to compare the lung function in very preterm infants with and without PDA at discharge. Methods Very preterm infants, admitted to our neonatal intensive unit, who required respiratory support soon after birth and had undergone a lung function test at discharge, were enrolled. Infants with a need for positive-pressure support (either an invasive ventilator, or nasal continuous positive airway pressure without oxygen) or supplemental oxygen at a postmenstrual age of 36 weeks were defined as having bronchopulmonary dysplasia (BPD). Echocardiography was performed weekly for each of the very preterm infants with PDA to confirm closure of the PDA. The data were collected retrospectively. Results Fifty-two very preterm infants received lung function tests before discharge during the study period, 28 of whom had PDA and received conservative management, and 20 who did not. The other 4 infants who were given active treatment for PDA were excluded. Gestational age was significantly smaller in the PDA group than in the no-PDA group (27.1 ± 2.0 vs. 28.6 ± 1.6 weeks, p = 0.009). Birth weight did not differ significantly in those with and those without PDA (0.98 ± 0.26 vs. 1.12 ± 0.26 kg, p = 0.074). Significantly more infants with PDA had BPD (p = 0.002) and required respiratory support for a longer period (p = 0.001) than those without PDA. However, functional residual capacity (ml/kg) at discharge was comparable between the two groups after adjusting for gestational age and postmenstrual age at testing (21.6 ± 8.4 vs. 21.5 ± 6.7 ml/kg, p = 0.894). Other lung function test parameters were also comparable. Conclusion Under a definition of BPD (including infants needing CPAP but without oxygen) other than the conventional definition, the very preterm infants in our study who received conservative management for PDA had a higher percentage of BPD than the infants without PDA. The parameters of the lung function test and lung clearance index were comparable between these two groups at discharge.
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Affiliation(s)
- Hsiu-Lin Chen
- Department of Respiratory Therapy, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. .,Department of Pediatrics, Kaohsiung Medical University Hospital, No.100 , Tzyou 1st Road, San Ming District, Kaohsiung, 807, Taiwan.
| | - Rei-Cheng Yang
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. .,Department of Pediatrics, Kaohsiung Medical University Hospital, No.100 , Tzyou 1st Road, San Ming District, Kaohsiung, 807, Taiwan.
| | - Wei-Te Lee
- Department of Pediatrics, Kaohsiung Medical University Hospital, No.100 , Tzyou 1st Road, San Ming District, Kaohsiung, 807, Taiwan.
| | - Pei-Lun Lee
- Department of Pediatrics, Kaohsiung Medical University Hospital, No.100 , Tzyou 1st Road, San Ming District, Kaohsiung, 807, Taiwan.
| | - Jong-Hau Hsu
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. .,Department of Pediatrics, Kaohsiung Medical University Hospital, No.100 , Tzyou 1st Road, San Ming District, Kaohsiung, 807, Taiwan.
| | - Jiunn-Ren Wu
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. .,Department of Pediatrics, Kaohsiung Medical University Hospital, No.100 , Tzyou 1st Road, San Ming District, Kaohsiung, 807, Taiwan.
| | - Zen-Kong Dai
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. .,Department of Pediatrics, Kaohsiung Medical University Hospital, No.100 , Tzyou 1st Road, San Ming District, Kaohsiung, 807, Taiwan.
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Thunqvist P, Gustafsson P, Norman M, Wickman M, Hallberg J. Lung function at 6 and 18 months after preterm birth in relation to severity of bronchopulmonary dysplasia. Pediatr Pulmonol 2015; 50:978-86. [PMID: 25187077 DOI: 10.1002/ppul.23090] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 06/19/2014] [Accepted: 07/25/2014] [Indexed: 11/11/2022]
Abstract
UNLABELLED Many preterm infants with bronchopulmonary dysplasia (BPD) demonstrate impaired lung function and respiratory symptoms during infancy. The relationships between initial BPD severity, lung function and respiratory morbidity are not fully understood. We aimed to investigate the association between BPD severity and subsequent lung function and whether lung function impairment is related to respiratory morbidity. STUDY DESIGN AND METHODS In this longitudinal cohort study, 55 infants born preterm (23-30 weeks of gestation) with mild or moderate/severe BPD, based on oxygen requirement at 36 gestational weeks, were followed up at 6 and 18 months postnatal age. Respiratory symptoms, such as recurrent or chronic chough and wheeze, were noted and patient records were scrutinized. Lung function was assessed by passive lung mechanics, whole body plethysmography, and tidal and raised volume rapid thoraco-abdominal compression techniques. Results were related to published normative values. RESULTS Besides residual functional capacity (FRC) and respiratory system compliance (Cso ) assessed at 18 months, all measures of lung function were significantly below normative values. Moderate/severe BPD differed significantly from mild BPD only with respect to reduced Cso . At follow-up at 6 and 18 months, participants with respiratory symptoms showed lower; maximal forced expiratory flow at FRC (V'maxFRC) (P = 0.006, P = 0.001), forced mid-expiratory flows (MEF50 ) (P = 0.006, P = 0.048), and Cso (P = 0.004, P = 0.015) as compared to participants without symptoms. CONCLUSIONS In the present study BPD severity did not predict lung function, but may be associated with impaired alveolarization, indicated by reduced Cso . Respiratory morbidity was associated with reduced airway function and respiratory compliance in infancy after preterm birth.
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Affiliation(s)
- Per Thunqvist
- Sachs' Children's Hospital, Department of Pediatrics, Södersjukhuset, 118 83, Stockholm, Sweden.,Karolinska Institute, Department of Clinical Science and Education, 171 77, Stockholm, Sweden
| | - Per Gustafsson
- The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.,Central Hospital, Department of Pediatrics, Skövde, Sweden
| | - Mikael Norman
- Karolinska Institute, Department of Clinical Science, Intervention and Technology, 141 86, Stockholm, Sweden
| | - Magnus Wickman
- Sachs' Children's Hospital, Department of Pediatrics, Södersjukhuset, 118 83, Stockholm, Sweden.,Karolinska Institute, Institute of Environmental Medicine, 171 77, Stockholm, Sweden
| | - Jenny Hallberg
- Sachs' Children's Hospital, Department of Pediatrics, Södersjukhuset, 118 83, Stockholm, Sweden.,Karolinska Institute, Institute of Environmental Medicine, 171 77, Stockholm, Sweden
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Determination of Lung Volume and Hemodynamic Changes During High-Frequency Ventilation Recruitment in Preterm Neonates With Respiratory Distress Syndrome. Crit Care Med 2015; 43:1685-91. [DOI: 10.1097/ccm.0000000000000967] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Healy F, Lin W, Feng R, Hanna BD, Hedrick H, Panitch HB. An association between pulmonary hypertension and impaired lung function in infants with congenital diaphragmatic hernia. Pediatr Pulmonol 2015; 50:672-82. [PMID: 24623605 DOI: 10.1002/ppul.23035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 02/16/2014] [Accepted: 02/20/2014] [Indexed: 02/02/2023]
Abstract
RATIONALE Infants with congenital diaphragmatic hernia (CDH) can develop pulmonary hypertension (PH) from decreased number and abnormal muscularization of pulmonary arteries. Normally pulmonary vascular growth and remodeling parallel airspace growth and alveolarization, which exhibits a wide morphologic variation in CDH. AIM To assess whether infants with CDH and PH have greater abnormalities in infant pulmonary function testing (IPFT) compared to those without PH. METHODS We reviewed results of IPFTs and echocardiograms performed on infants with CDH from 2004 to June 2011. Lung volumes, forced flows and tidal mechanics were standardized according to available reference values. Comparisons between infants with and without PH were performed using linear regression, adjusting for potential confounders. MAIN RESULTS Sixty-six infants were included; 18 had PH and 48 did not. Z-score values for functional residual capacity (FRC), residual volume (RV), FRC/total lung capacity (TLC), and RV/TLC were significantly higher in infants with CDH and PH compared to those without PH. Z-score values for forced flows including forced expiratory volume in the first 0.5 sec (FEV0.5) and FEV0.5/forced vital capacity were significantly lower in infants with CDH and PH compared to those without PH. For 29 infants studied on ≥2 occasions, the slopes of FRC, RV, and TLC versus length were significantly higher in those with persistent PH compared to those without. CONCLUSIONS Infants with CDH and persistent PH demonstrate greater airspace overdistension with growth compared to those without. Therapies that modify disrupted pulmonary vascular and alveolar formation could potentially improve future care of these patients.
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Affiliation(s)
- Fiona Healy
- Division of Pulmonary Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Wei Lin
- Department of Biostatistics & Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Rui Feng
- Department of Biostatistics & Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Brian D Hanna
- Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Holly Hedrick
- Department of General Surgery, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Howard B Panitch
- Division of Pulmonary Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
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Hjalmarson O, Brynjarsson H, Nilsson S, Sandberg KL. Persisting hypoxaemia is an insufficient measure of adverse lung function in very immature infants. Arch Dis Child Fetal Neonatal Ed 2014; 99:F257-62. [PMID: 24356176 DOI: 10.1136/archdischild-2013-304625] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Bronchopulmonary dysplasia (BPD), defined as protracted neonatal hypoxaemia, is considered a risk factor for respiratory disease in adulthood. The relationship between this diagnosis and the actual lung injury appearing in very immature infants is, however, unknown. OBJECTIVES To compare lung function at term in very immature infants and full-term infants, and to determine how degree and duration of neonatal hypoxaemia are related to other aspects of lung function. DESIGN AND METHODS All surviving, consecutive infants with gestational age below 28 weeks from a geographically defined area were eligible. The alveolar-arterial oxygen pressure difference was assessed as a measure of oxygenation failure. At term, functional residual capacity and gas-mixing efficiency were measured by multiple-breath nitrogen washout, and compliance and conductance of the respiratory system by the occlusion method. The results were compared to those in 50 full-term controls. MAIN RESULTS Thirty-seven of 46 eligible infants were included. The preterm infants differed markedly from the full-term infants in all lung functions tested. Infants diagnosed as having BPD had more compromised lung function than those without, but the latter group differed markedly from the full-term group in functional residual capacity, compliance and gas-mixing efficiency. Only the mechanical variables were correlated to hypoxaemia at 36 weeks postmenstrual age (PMA). CONCLUSIONS Infants with gestational age below 28 weeks at birth have remarkably impaired lung function at term, regardless of whether they carry the diagnosis BPD or not. All very immature infants may be at risk of future respiratory disease and should be monitored appropriately.
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Vogt B, Falkenberg C, Weiler N, Frerichs I. Pulmonary function testing in children and infants. Physiol Meas 2014; 35:R59-90. [PMID: 24557323 DOI: 10.1088/0967-3334/35/3/r59] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Pulmonary function testing is performed in children and infants with the aim of documenting lung development with age and making diagnoses of lung diseases. In children and infants with an established lung disease, pulmonary function is tested to assess the disease progression and the efficacy of therapy. It is difficult to carry out the measurements in this age group without disturbances, so obtaining results of good quality and reproducibility is challenging. Young children are often uncooperative during the examinations. This is partly related to their young age but also due to the long testing duration and the unpopular equipment. We address a variety of examination techniques for lung function assessment in children and infants in this review. We describe the measuring principles, examination procedures, clinical findings and their interpretation, as well as advantages and limitations of these methods. The comparability between devices and centres as well as the availability of reference values are still considered a challenge in many of these techniques. In recent years, new technologies have emerged allowing the assessment of lung function not only on the global level but also on the regional level. This opens new possibilities for detecting regional lung function heterogeneity that might lead to a better understanding of respiratory pathophysiology in children.
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Affiliation(s)
- B Vogt
- Department of Anaesthesiology and Intensive Care Medicine, University Medical Centre Schleswig-Holstein, Campus Kiel, Kiel, Germany
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25
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Landolfo F, Savignoni F, Capolupo I, Columbo C, Calzolari F, Giliberti P, Chukhlantseva N, Bagolan P, Dotta A. Functional residual capacity (FRC) and lung clearance index (LCI) in mechanically ventilated infants: application in the newborn with congenital diaphragmatic hernia (CDH). J Pediatr Surg 2013; 48:1459-62. [PMID: 23895954 DOI: 10.1016/j.jpedsurg.2012.12.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 12/13/2012] [Accepted: 12/15/2012] [Indexed: 10/26/2022]
Abstract
INTRODUCTION Functional residual capacity (FRC) and lung clearance index (LCI) are sensitive parameters for early detection of airway disease in infancy. The closed helium dilution method has been applied to assess lung volume and ventilation inhomogeneity (VI) in spontaneously breathing infants. AIMS The aims of this study were as follows: (1) to assess applicability of the helium gas dilution technique in mechanically ventilated infants with high-risk congenital diaphragmatic hernia (CDH) and to evaluate changes in breathing patterns, lung volume, and VI during the first days of life before and after surgery, and (2) to analyze the possible correlation between changes in lung volume, cerebral hemodynamics, and oxygenation before and after surgical correction of CDH through near-infrared spectroscopy (NIRS) monitoring. METHODS Lung function tests were performed by multibreath washout traces with an ultrasonic flowmeter and helium gas dilution technique. For all babies, three acceptable FRC and LCI measurements were collected for each test (mean and SD of three measurements were calculated) before surgery (T0), 24 h after surgery (T1) during mechanical ventilation, and within 24 h after extubation in spontaneous breathing (T2). Cerebral and splanchnic hemodynamics were continuously monitored by NIRS during mechanical ventilation to evaluate relationships between changes in lung volume and capillary-venous oxyhemoglobin saturation in tissues. Fraction of inspired oxygen delivered was adjusted to keep oxygen saturation between 90% and 95%. RESULTS Thirteen CDH infants were studied; median GA = 38 weeks (range 35-41) and median BW = 3000 g (range 1850-3670). FRC and LCI significantly improved after extubation when compared with pre-surgical values. No differences were found in tidal volume (Vt) and NIRS monitoring before and after surgery and after extubation. Neither LCI nor FRC was correlated with NIRS values. CONCLUSIONS Helium gas dilution technique is an applicable and reliable technique to measure lung volumes and ventilation inhomogeneity also in ventilated infants. NIRS is a non-invasive technique to monitor tissue oxygenation during surgery and mechanical ventilation. In CDH newborns these preliminary data show an improvement in both FRC and LCI after extubation.
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Affiliation(s)
- Francesca Landolfo
- Department of Medical and Surgical Neonatology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
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Nguyen TTD, Hoo AF, Lum S, Wade A, Thia LP, Stocks J. New reference equations to improve interpretation of infant lung function. Pediatr Pulmonol 2013; 48:370-80. [PMID: 22949414 DOI: 10.1002/ppul.22656] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 04/30/2012] [Indexed: 11/07/2022]
Abstract
RATIONALE With increasing use of infant pulmonary function tests (IPFTs) in both clinical and research studies, appropriate interpretation of results is essential. OBJECTIVES To investigate the potential bias associated with "normalising" IPF by expressing results as a ratio of body size and to develop reference ranges for tidal breathing parameters, passive respiratory mechanics (compliance [Crs] and resistance [Rrs]) and plethysmographic functional residual capacity (FRCp ) for white infants during the first 2 years of life. METHODS IPFTs were measured using the Jaeger BabyBody system and standardized protocols. Reference equations, adjusted for body size, age, and sex where appropriate, were created using multilevel modeling. RESULTS The ratio of lung function to body length changes markedly with growth, thereby precluding its use for any outcome. While the ratio of tidal volume and Crs to body weight remained relatively constant with growth, this was not the case for FRCp . Even in healthy infants, a strong inverse relationship was observed between lung function/body weight and weight z-score which could distort interpretation of results in growth-restricted infants with lung disease, such as cystic fibrosis. Reference equations were derived from 153 healthy white infants on 232 test occasions (median age 35.5 weeks [range: 2.6-104.7]). Crown-heel length was the strongest predictor of IPF. CONCLUSIONS When reporting IPF, use of size-corrected ratios should be discouraged, with interpretation instead based on appropriate reference equations. The current equations are applicable to white infants and young children up to 2 years of age, studied using the same commercially available equipment. The extent to which these equations are applicable to infants and young children of other ethnic backgrounds or who are tested with different equipment needs to be established.
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Affiliation(s)
- The Thanh Diem Nguyen
- Portex Respiratory Unit, UCL Institute of Child Health and Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
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Spoel M, Meeussen CJHM, Gischler SJ, Hop WCJ, Bax NMA, Wijnen RMH, Tibboel D, de Jongste JC, Ijsselstijn H. Respiratory morbidity and growth after open thoracotomy or thoracoscopic repair of esophageal atresia. J Pediatr Surg 2012; 47:1975-83. [PMID: 23163986 DOI: 10.1016/j.jpedsurg.2012.07.044] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 07/10/2012] [Accepted: 07/15/2012] [Indexed: 01/03/2023]
Abstract
BACKGROUND Respiratory morbidity has been described in patients who underwent repair of esophageal atresia as a neonate. We compared the influence of open thoracotomy or thoracoscopy on lung function, respiratory symptoms, and growth. METHODS Functional residual capacity (FRC(p)), indicative of lung volume, and maximal expiratory flow at functional residual capacity (V'max(FRC)), indicative of airway patency, of 37 infants operated for esophageal atresia were measured with Masterscreen Babybody at 6 and 12 months. SD scores were calculated for V'max(FRC). RESULTS Repair was by thoracotomy in 21 cases (57%) and by thoracoscopy in 16 cases (43%). Lung function parameters did not differ between the types of surgery (FRC(p); P = .384 and V'max(FRC); P = .241). FRC(p) values were in the upper normal range and increased from 6 to 12 months (22.5 and 25.4 mL/kg respectively, P = .010). Mean (SD) V'max(FRC) was below the norm without significant change in SD scores from 6 to 12 months (-1.9 and -2.3, respectively, P = .248). Neither lung function nor type of repair was associated with clinical evolution up to 2 years. CONCLUSION Lung function during the first year was similar in EA infants repaired by thoracotomy or thoracoscopy. Ongoing follow-up including pulmonary function testing is needed to determine whether differences occur at a later age in this cohort.
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Affiliation(s)
- Marjolein Spoel
- Intensive Care and Department of Pediatric Surgery, Erasmus Medical Centre/Sophia Children's Hospital, Rotterdam, The Netherlands.
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Prospective longitudinal evaluation of lung function during the first year of life after repair of congenital diaphragmatic hernia. Pediatr Crit Care Med 2012; 13:e133-9. [PMID: 21666527 DOI: 10.1097/pcc.0b013e3182231872] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
OBJECTIVE To evaluate lung function and respiratory morbidity prospectively during the first year of life in patients with congenital diaphragmatic hernia and to study the effect of extracorporeal membrane oxygenation therapy. DESIGN Prospective longitudinal cohort study. SETTING Outpatient clinic of a tertiary-level pediatric hospital. PATIENTS The cohort of 43 infants included 12 patients treated with extracorporeal membrane oxygenation. Evaluation was at 6 and 12 months; 33 infants were evaluated at both time points. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Maximal expiratory flow at functional residual capacity and functional residual capacity were measured with Masterscreen Babybody. Z-scores were calculated for maximal expiratory flow at functional residual capacity. Mean maximal expiratory flow at functional residual capacity values at 6 and 12 months were significantly below the expected values (mean z-score -1.4 and -1.5, respectively) without a significant change between both time points. Values did not significantly differ between extracorporeal membrane oxygenation and nonextracorporeal membrane oxygenation-treated patients. Functional residual capacity values were generally high, 47% were above the suggested normal range, and did not change significantly over time. Mean functional residual capacity values in extracorporeal membrane oxygenation-treated patients were significantly higher than in nonextracorporeal membrane oxygenation-treated patients (p = .006). The difference (5.1 mL/kg ± 1.8 SE) did not change significantly between the two time points. Higher mean airway pressure and longer duration of ventilation were associated with higher functional residual capacity. None of the perinatal characteristics was associated with maximal expiratory flow at functional residual capacity. Mean weight z-scores were significantly below zero at both time points (p < .001). Mean weight z-score in extracorporeal membrane oxygenation-treated patients were lower than in nonextracorporeal membrane oxygenation-treated patients (p = .046). CONCLUSIONS Infants with congenital diaphragmatic hernia have decreased expiratory flows and increased functional residual capacity within the first year of life. Extracorporeal membrane oxygenation-treated patients with congenital diaphragmatic hernia may have more respiratory morbidity and concomitant growth impairment. Close follow-up beyond the neonatal period is therefore required.
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Technical problems with dynamic compliance evaluation in neonates and infants. Intensive Care Med 2012; 38:1082-3. [DOI: 10.1007/s00134-012-2522-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/28/2011] [Indexed: 10/28/2022]
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Abstract
Multiple breath washout (MBW) has been demonstrated to be sensitive for assessing ventilation inhomogeneity (VI). VI is supposed to reflect changes in peripheral airways which are not apparent using spirometry. The lung clearance index (LCI) is the most robust parameter to quantify VI, and is largely independent of age; therefore, it potentially qualifies as a surrogate outcome parameter for clinical and research purposes, particularly during childhood. This review summarizes the current evidence regarding the clinical value of measuring LCI in children. Feasibility, reproducibility and diagnostic accuracy have been demonstrated; available data confirm that LCI is superior to spirometry in detecting small air way disease. However, there is little information regarding the value in the individual patient, and sparse longitudinal data looking at its prognostic value. Currently, only in patients with Cystic Fibrosis, it appears likely that knowledge of LCI will be useful for routine clinical management.
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Affiliation(s)
- Susanne I Fuchs
- Children's Hospital and Research Institute, Marien-Hospital Wesel gGmbH, Pastor-Janssen-Str. 8-38, 46483 Wesel, Germany
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Mann C, Bär W. Severe bronchopulmonary dysplasia improved by noninvasive positive pressure ventilation: a case report. J Med Case Rep 2011; 5:435. [PMID: 21896175 PMCID: PMC3180418 DOI: 10.1186/1752-1947-5-435] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 09/06/2011] [Indexed: 12/03/2022] Open
Abstract
Introduction This is the first report to describe the feasibility and effectiveness of noninvasive positive pressure ventilation in the secondary treatment of bronchopulmonary dysplasia. Case presentation A former male preterm of Caucasian ethnicity delivered at 29 weeks gestation developed severe bronchopulmonary dysplasia. At the age of six months he was in permanent tachypnea and dyspnea and in need of 100% oxygen with a flow of 2.0 L/minute via a nasal cannula. Intermittent nocturnal noninvasive positive pressure ventilation was then administered for seven hours daily. The ventilator was set at a positive end-expiratory pressure of 6 cmH2O, with pressure support of 4 cmH2O, trigger at 1.4 mL/second, and a maximum inspiratory time of 0.7 seconds. Over the course of seven weeks, the patient's maximum daytime fraction of inspired oxygen via nasal cannula decreased from 1.0 to 0.75, his respiratory rate from 64 breaths/minute to 50 breaths/minute and carbon dioxide from 58 mmHg to 44 mmHg. Conclusion Noninvasive positive pressure ventilation may be a novel therapeutic option for established severe bronchopulmonary dysplasia. In the case presented, noninvasive positive pressure ventilation achieved sustained improvement in ventilation and thus prepared our patient for safe home oxygen therapy.
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Affiliation(s)
- Christian Mann
- Neonatal and Pediatric Intensive Care Unit, Graubuenden Cantonal Hospital, Loestr 170, CH-7000 Chur, Switzerland.
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Lesnick BL, Davis SD. Infant pulmonary function testing: overview of technology and practical considerations--new current procedural terminology codes effective 2010. Chest 2011; 139:1197-1202. [PMID: 21540218 DOI: 10.1378/chest.10-1423] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Infant pulmonary function testing has evolved from a research technique into a diagnostic tool. As such, new current procedural terminology (CPT) codes have been created and are available for use as of January 1, 2010. The technology now available has a range of applications. Through a series of vignettes, this article illustrates the methodology of the tests, some of their applications, and how to code and bill for the procedures.
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Affiliation(s)
- Burton L Lesnick
- From Georgia Pediatric Pulmonary Associates, Atlanta, GA; Morehouse School of Medicine, Chapel Hill, NC.
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Lum S, Bush A, Stocks J. Clinical Pulmonary Function Testing for Children with Bronchopulmonary Dysplasia. PEDIATRIC ALLERGY IMMUNOLOGY AND PULMONOLOGY 2011; 24:77-88. [DOI: 10.1089/ped.2010.0059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Sooky Lum
- Portex Respiratory Unit, UCL, Institute of Child Health, London, United Kingdom
| | - Andrew Bush
- Department of Paediatrics, Royal Brompton Hospital, London, United Kingdom
| | - Janet Stocks
- Portex Respiratory Unit, UCL, Institute of Child Health, London, United Kingdom
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Leonhardt S, Ahrens P, Kecman V. Analysis of Tidal Breathing Flow Volume Loops for Automated Lung-Function Diagnosis in Infants. IEEE Trans Biomed Eng 2010; 57:1945-53. [DOI: 10.1109/tbme.2010.2046168] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Schulzke SM, Hall GL, Nathan EA, Simmer K, Nolan G, Pillow JJ. Lung volume and ventilation inhomogeneity in preterm infants at 15-18 months corrected age. J Pediatr 2010; 156:542-9.e2. [PMID: 20022341 DOI: 10.1016/j.jpeds.2009.10.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 09/01/2009] [Accepted: 10/15/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To assess whether lung volume and ventilation inhomogeneity in preterm infants at 15-18 months corrected age, and the change in these outcomes from the newborn period to 15-18 months corrected age, depend on gestational age (GA) at birth and the severity of neonatal lung disease. STUDY DESIGN Preterm (GA range, 23-32 weeks) and term healthy control infants were studied in quiet sedated sleep at 15-18 months corrected age by multiple breath washout with 5% sulfur hexafluoride using an ultrasonic flowmeter. Valid measurements were obtained from 58 infants. Multivariate and multilevel regression was used to analyze outcomes. RESULTS Functional residual capacity (FRC), lung clearance index, and first and second to zeroeth moment ratios were calculated. After accounting for body size at test, FRC at follow-up, and the increase in FRC from the newborn period to 15-18 months corrected age were positively associated with GA and negatively associated with the duration of endotracheal ventilation. Indices of ventilation inhomogeneity were unaltered by GA and the duration of endotracheal ventilation. CONCLUSIONS In very preterm infants, GA and the duration of endotracheal ventilation are independently associated with reduced lung volume and lung growth during infancy, although the effect size of these findings is small.
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Affiliation(s)
- Sven M Schulzke
- School of Women's and Infant's Health, University of Western Australia, Perth, Australia.
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Olegård C, Søndergaard S, Pålsson J, Lundin S, Stenqvist O. Validation and clinical feasibility of nitrogen washin/washout functional residual capacity measurements in children. Acta Anaesthesiol Scand 2010; 54:370-6. [PMID: 19839952 DOI: 10.1111/j.1399-6576.2009.02107.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The functional residual capacity (FRC) is an important parameter in pediatric respiratory monitoring but it is difficult to assess in the clinical setting. We have introduced a modified N(2) washout method utilizing a change of F(I)O(2) of 0.1 for FRC measurement in adult respiratory monitoring. This study validated the algorithm in a pediatric lung model and investigated the stability and feasibility in a pediatric peri-operative and intensive care setting. METHODS The lung model was ventilated in combinations of ventilatory modes, CO(2) production, model FRC and respiratory rates. Sixteen children from 10 days to 5 years were studied peri-operatively with controlled ventilation using a Mapleson D system and in the intensive care unit using a Servo-i ventilator in a supported spontaneous mode. FRC was measured during stable metabolic, respiratory and circulatory periods at positive end expiratory pressure of 3-4 and 7-8 cmH(2)O. RESULTS In the model and in the clinical setting, we found an excellent agreement between washout and washin measurements of FRC as well as acceptable coefficients of repeatability. CONCLUSION FRC was satisfactorily measured by a modified N(2) algorithm and may be included as a monitoring variable in pediatric respiratory care. Pediatric FRC monitoring demands strictly stable conditions as measurements are performed close to the limits of the monitor's specifications.
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Affiliation(s)
- C Olegård
- Department of Anaesthesia and Intensive Care, Sahlgrenska University Hospital, 413 45 Gothenburg, Sweden.
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Morris MG. Comprehensive integrated spirometry using raised volume passive and forced expirations and multiple-breath nitrogen washout in infants. Respir Physiol Neurobiol 2010; 170:123-40. [PMID: 19897058 PMCID: PMC2858579 DOI: 10.1016/j.resp.2009.10.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2009] [Revised: 10/29/2009] [Accepted: 10/29/2009] [Indexed: 12/15/2022]
Abstract
With the rapid somatic growth and development in infants, simultaneous accurate measurements of lung volume and airway function are essential. Raised volume rapid thoracoabdominal compression (RTC) is widely used to generate forced expiration from an airway opening pressure of 30 cmH(2)O (V(30)). The (dynamic) functional residual capacity (FRC(dyn)) remains the lung volume most routinely measured. The aim of this study was to develop comprehensive integrated spirometry that included all subdivisions of lung volume at V(30) or total lung capacity (TLC(30)). Measurements were performed on 17 healthy infants aged 8.6-119.7 weeks. A commercial system for multiple-breath nitrogen washout (MBNW) to measure lung volumes and a custom made system to perform RTC were used in unison. A refined automated raised volume RTC and the following two novel single maneuvers with dual volume measurements were performed from V(30) during a brief post-hyperventilation apneic pause: (1) the passive expiratory flow was integrated to produce the inspiratory capacity (IC) and the static (passive) FRC (FRC(st)) was estimated by initiating MBNW after end-passive expiration; (2) RTC was initiated late during passive expiration, flow was integrated to produce the slow vital capacity ((j)SVC) and the residual volume (RV) was measured by initiating MBNW after end-expiration while the jacket (j) was inflated. Intrasubject FRC(dyn) and FRC(st) measurements overlapped (p=0.6420) but neither did with the RV (p<0.0001). Means (95% confidence interval) of FRC(dyn), IC, FRC(st), (j)SVC, RV, forced vital capacity and tidal volume were 21.2 (19.7-22.7), 36.7 (33.0-40.4), 21.2 (19.6-22.8), 40.7 (37.2-44.2), 18.1 (16.6-19.7), 40.7 (37.1-44.2) and 10.2 (9.6-10.7)ml/kg, respectively. Static lung volumes and capacities at V(30) and variables from the best forced expiratory flow-volume curve were dependent on age, body length and weight. In conclusion, we developed a comprehensive physiologically integrated approach for in-depth investigation of lung function at V(30) in infants.
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Affiliation(s)
- Mohy G Morris
- Department of Pediatrics, Pulmonary Medicine Section, College of Medicine, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, AR 72202, USA.
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Morris MG. A novel physiological investigation of the functional residual capacity by the bias flow nitrogen washout technique in infants. Pediatr Pulmonol 2009; 44:683-92. [PMID: 19499588 PMCID: PMC3032594 DOI: 10.1002/ppul.21040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The dynamic functional residual capacity (FRC(dyn)), the lung volume most routinely measured in infants, is an unreliable volume landmark. In addition to the FRC(dyn), we measured the (passive) static FRC (FRC(st)) by inducing a brief post-hyperventilation apnea (PHA) in 33 healthy infants aged 7.4-127.2 weeks. A commercial system for nitrogen (N2) washout to measure FRC, and a custom made system to monitor and record flow and airway opening pressure signals in real-time were used in unison. Infants were manually hyperventilated to induce a PHA. After the last passive expiration, FRC(st) was estimated by measuring the volume of N2 expired after end-passive expiratory switching of the inspired gas from room air to 100% oxygen during the post-expiratory apneic pause. Repeatable intrasubject FRC(st) and FRC(dyn) measurements overlapped in most infants including the younger ones (P = 0.2839). Mean (95% confidence interval [CI]) FRC(st) was 21.1 (20.0-22.3), and error-corrected FRC(dyn) was 21.4 (20.4-22.4) ml/kg. Mean (washout time [t]) tFRC(st) was longer than tFRC(dyn) 60 sec (95% CI 55-65) versus 47 sec (95% CI 43-51) (P < 0.0001). The FRC and washout time were dependent on body length, weight and age. We conclude that the FRC(st) is not different from the FRC(dyn) in infants. The FRC(st) is a reliable volume landmark because the PHA stabilizes the end-expiratory level by potentially abolishing the sedated infant's breathing strategies. The FRC(st) lacks potential sources of errors and disadvantages associated with measuring the FRC(dyn). The findings cast significant doubt on the traditional physiology of air trapping in healthy infants' lungs.
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Affiliation(s)
- Mohy G Morris
- Department of Pediatrics, Pulmonary Medicine Section, College of Medicine, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, 1 Children's Way, Slot 512-17, Little Rock, AR 72202, USA.
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Lung volume, breathing pattern and ventilation inhomogeneity in preterm and term infants. PLoS One 2009; 4:e4635. [PMID: 19247491 PMCID: PMC2645689 DOI: 10.1371/journal.pone.0004635] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2008] [Accepted: 01/21/2009] [Indexed: 11/24/2022] Open
Abstract
Background Morphological changes in preterm infants with bronchopulmonary dysplasia (BPD) have functional consequences on lung volume, ventilation inhomogeneity and respiratory mechanics. Although some studies have shown lower lung volumes and increased ventilation inhomogeneity in BPD infants, conflicting results exist possibly due to differences in sedation and measurement techniques. Methodology/Principal Findings We studied 127 infants with BPD, 58 preterm infants without BPD and 239 healthy term-born infants, at a matched post-conceptional age of 44 weeks during quiet natural sleep according to ATS/ERS standards. Lung function parameters measured were functional residual capacity (FRC) and ventilation inhomogeneity by multiple breath washout as well as tidal breathing parameters. Preterm infants with BPD had only marginally lower FRC (21.4 mL/kg) than preterm infants without BPD (23.4 mL/kg) and term-born infants (22.6 mL/kg), though there was no trend with disease severity. They also showed higher respiratory rates and lower ratios of time to peak expiratory flow and expiratory time (tPTEF/tE) than healthy preterm and term controls. These changes were related to disease severity. No differences were found for ventilation inhomogeneity. Conclusions Our results suggest that preterm infants with BPD have a high capacity to maintain functional lung volume during natural sleep. The alterations in breathing pattern with disease severity may reflect presence of adaptive mechanisms to cope with the disease process.
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May C, Prendergast M, Salman S, Rafferty GF, Greenough A. Chest radiograph thoracic areas and lung volumes in infants developing bronchopulmonary dysplasia. Pediatr Pulmonol 2009; 44:80-5. [PMID: 19085927 DOI: 10.1002/ppul.20952] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVES To determine whether chest radiograph (CXR) thoracic areas and lung volumes differed between infants who did and did not develop BPD and according to the severity of BPD developed. WORKING HYPOTHESIS Infants developing BPD, particularly if moderate or severe, would have low CXR thoracic areas and lung volumes in the perinatal period. STUDY DESIGN Prospective study. PATIENT-SUBJECT SELECTION: 53 infants with a median gestational age of 28 (range 24-32) weeks. METHODOLOGY CXR thoracic areas were calculated using a Picture Archiving and Communicating System (PACS) and lung volume assessed by measurement of functional residual capacity (FRC) in the first 72 hr after birth. BPD was diagnosed if the infants were oxygen dependent beyond 28 days, mild BPD in infants no longer oxygen dependent at 36 weeks post-menstrual age (PMA) and moderate/severe BPD in infants who required supplementary oxygen with or without respiratory support at 36 weeks PMA. RESULTS Thirty two infants developed BPD, 21 had moderate/severe BPD. The median CXR thoracic areas were higher (P < 0.0001) and FRCs were lower (P < 0.0001) in the BPD compared to no BPD infants. The median CXR thoracic areas of the moderate/severe group (P < 0.001) and the mild group (P < 0.05) were greater than that of the no BPD group and the median FRC of the moderate/severe BPD group was lower than the no BPD group (<0.001) and the mild BPD group (P < 0.05). CONCLUSION These results highlight that in the perinatal period infants developing BPD, particularly if moderate/severe, have low functional lung volumes and may have gas trapping, which likely reflects ventilation inhomogeneity.
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Affiliation(s)
- Caroline May
- MRC-Asthma Centre, Division of Asthma, Allergy and Lung Biology, King's College London, London, UK
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Riedel T, Kyburz M, Latzin P, Thamrin C, Frey U. Regional and overall ventilation inhomogeneities in preterm and term-born infants. Intensive Care Med 2008; 35:144-51. [DOI: 10.1007/s00134-008-1299-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Accepted: 09/03/2008] [Indexed: 10/21/2022]
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Gauthier R, Matecki S, Le Bourgeois M, Couderc L. [Evaluation of respiratory function in infants with cystic fibrosis. Synopsis of the "Respiratory Functional Explorations" working group of the French Society of Cystic Fibrosis (CRCM)]. REVUE DE PNEUMOLOGIE CLINIQUE 2007; 63:254-262. [PMID: 17978737 DOI: 10.1016/s0761-8417(07)92649-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Affiliation(s)
- R Gauthier
- Unité d'Explorations Fonctionnelles Respiratoires Pédiatriques et NéoNatales, CHU Nord, place Victor-Pauchet, 80054 Amiens.
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Elgeti T, Proquitté H, Rogalla NE, Mews J, Hamm B, Schmalisch G, Rogalla P. Evaluation of a Reduced Dose Protocol for Respiratory Gated Lung Computed Tomography in an Animal Model. Invest Radiol 2007; 42:230-4. [PMID: 17351429 DOI: 10.1097/01.rli.0000255817.54192.eb] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE We sought to evaluate and validate a low-dose protocol for respiratory-gated multislice computed tomography (CT) for volume calculations in small ventilated neonatal animals as a model for the ventilated human neonatal lung. MATERIALS AND METHODS Five mechanically ventilated newborn piglets were imaged in a multislice CT scanner (0.5-mm slice thickness, 4:16 pitch, 0.5 seconds rotation time, 120 kV) using a normal (100 mAs) and a reduced (10 mAs) dose protocol. All animals were scanned twice (at 100 and 10 mAs) at each of 3 different ventilator settings. Complete volume datasets were reconstructed throughout the respiratory cycle in increments of 10% using retrospective half-scan reconstruction. End-inspiratory volumes and volumes during maximal expiration (functional residual capacity) were calculated by a customized software and values for normal and reduced dose protocols were compared using Kolmogorov-Smirnov test and Bland-Altman plots. RESULTS Two volume datasets (one normal and one reduced dose protocol) showed artifacts on the axial images, which could not be analyzed by the software. Those values were determined after manual segmentation and excluded from final analysis. The mean (+/-SD) end-inspiratory volumes and functional residual capacity were 34.3 +/- 10.1 mL and 25.3 +/- 8.0 mL for the normal-dose protocol versus 33.1 +/- 10.0 mL and 24.7 +/- 8.1 mL for the reduced-dose protocol, respectively. There was no statistically significant difference between normal and reduced dose protocol (KS-Test: D = 0.14 < Dmax). CONCLUSION Lung volume calculation in ventilated newborn piglets (end-inspiratory volumes and functional residual capacity) can be performed using respiratory-gated multislice CT even at a substantially reduced dose (eg, to 10 mAs). This makes the technique a candidate for future pediatric use.
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Affiliation(s)
- Thomas Elgeti
- Department of Radiology, Charité Campus Mitte, Universitätsmedizin Berlin, Germany.
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van Kaam AH, Rimensberger PC. Lung-protective ventilation strategies in neonatology: What do we know—What do we need to know? Crit Care Med 2007; 35:925-31. [PMID: 17255875 DOI: 10.1097/01.ccm.0000256724.70601.3a] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Randomized controlled trials (RCTs) investigating various lung-protective ventilation modes or strategies in newborn infants have failed to show clear differences in mortality or bronchopulmonary dysplasia. This review tries to identify possible reasons for this observation, applying modern concepts on ventilator-induced lung injury and lung-protective ventilation. DATA SOURCE Published RCTs and systematic reviews on mechanical ventilation in newborn infants were identified by searching PubMed and the Cochrane Library. DATA SYNTHESIS A total of 16 RCTs and four systematic reviews comparing high-frequency ventilation with conventional mechanical ventilation (CMV) failed to show consistent differences in mortality and bronchopulmonary dysplasia. Unfortunately, clear information or data on ventilation and oxygenation targets in the search for optimal lung volumes during high-frequency ventilation or CMV is lacking in many RCTs, questioning the validity of the results and the meta-analytic subgroup analysis. Based on improvement in oxygenation, only three RCTs successfully applied the optimal lung volume strategy during high-frequency ventilation. A total of 24 RCTs and three systematic reviews comparing various CMV modes and settings and two RCTs investigating permissive hypercapnia reported no differences in mortality or bronchopulmonary dysplasia. However, the intervention arms in these RCTs did not differ in tidal volume or positive end-expiratory pressures, variables that are considered important determinants in ventilator-induced lung injury. In fact, no RCT in newborn infants has substantiated so far the experimental finding that avoiding large tidal volumes and low positive end-expiratory pressure during CMV is lung protective in newborn infants. CONCLUSION RCTs investigating lung-protective ventilation in neonates have mainly focused on comparing high-frequency ventilation with CMV. Most of these RCTs show weaknesses in the design, which may explain the inconsistent effect of high-frequency ventilation on bronchopulmonary dysplasia. RCTs on CMV only focused on comparing various modes and settings, leaving the important question whether reducing tidal volume or increasing positive end-expiratory pressure is also lung protective in newborn infants unanswered.
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Affiliation(s)
- Anton H van Kaam
- Department of Neonatology, Emma Children's Hospital AMC, University of Amsterdam, Amsterdam, The Netherlands
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Stocks J, Coates A, Bush A. Lung function in infants and young children with chronic lung disease of infancy: the next steps? Pediatr Pulmonol 2007; 42:3-9. [PMID: 17123320 DOI: 10.1002/ppul.20520] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Over the past year, a series of papers have reviewed the literature concerning assessment and interpretation of lung function in infants and young children with chronic lung disease of infancy. This manuscript, which represents the final paper in that series, summarizes the findings to date and highlights key areas for future research. Despite the huge literature in this field, interpretation of results and their use in guiding clinical management are still limited by difficulties in 'normalizing data' according to body size and maturation and selection of appropriate control groups. Furthermore, sensitive tests that more closely reflect the underlying pathophysiology of 'new' bronchopulmonary dysplasia, together with simple and reliable methods of assessing lung maturity at birth and true oxygen requirements at specified time points are urgently required. Research in this field is also challenged by the need to separate the independent effects of genetic predisposition, gene-environment interactions, preterm delivery, neonatal respiratory disorders and various treatment strategies on the growing lung. The extent to which disruption of lung growth following premature exposure to the extra-uterine environment leads to an earlier or more aggravated decline in respiratory function in later adult life remains to be elucidated. Whatever its origin, given the increasing survival of smaller and more immature infants, the long term sequelae of neonatal lung disease, are likely to continue to change, requiring ongoing, carefully designed longitudinal studies. Future research strategies need to encompass a multicenter, multi-disciplinary, collaborative approach with closer links between clinicians and basic scientists, to ensure that the most relevant research questions are addressed using appropriate methodology and that findings are implemented into clinical practice in a more timely fashion.
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Affiliation(s)
- Janet Stocks
- Portex Anaesthesia, Intensive Therapy and Respiratory Medicine Unit, UCL, Institute of Child Health and Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom.
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De Jaegere A, van Veenendaal MB, Michiels A, van Kaam AH. Lung Recruitment Using Oxygenation during Open Lung High-Frequency Ventilation in Preterm Infants. Am J Respir Crit Care Med 2006; 174:639-45. [PMID: 16763218 DOI: 10.1164/rccm.200603-351oc] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Changes in oxygenation are often used to guide the recruitment procedure during open lung high-frequency ventilation in preterm infants. However, data on the feasibility and safety of this approach in daily clinical practice are limited. OBJECTIVE To prospectively collect data on ventilator settings, gas exchange, and circulatory parameters before and after surfactant therapy during open lung high-frequency ventilation. METHODS In 103 preterm infants with respiratory distress syndrome, the opening, closing, and optimal pressures were determined during high-frequency ventilation by increasing and decreasing stepwise the continuous distending pressure, defining optimal recruitment as adequate oxygenation using a fraction of inspired oxygen not exceeding 0.25. This procedure was repeated after each surfactant treatment. MEASUREMENTS AND MAIN RESULTS The mean presurfactant opening and optimal continuous distending pressures were, respectively, 20.5 +/- 4.3 and 14.0 +/- 4.0 cm H2O, with a fraction of inspired oxygen of 0.24 +/- 0.04. Surfactant treatment enabled a reduction in the mean optimal pressure of almost 6 cm H2O without compromising oxygenation. Blood pressure and heart rate remained stable and no air leaks were observed during the recruitment procedures. The mortality rate and the incidence of severe intracranial hemorrhage or periventricular leukomalacia and chronic lung disease at 36 wk were comparable to previously reported data. CONCLUSION Open lung high-frequency ventilation using oxygenation to guide the recruitment process is feasible and safe in preterm infants and enables a reduction of the fraction of inspired oxygen below 0.25 in the majority of preterm infants with respiratory distress syndrome.
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Affiliation(s)
- Anne De Jaegere
- Department of Neonatology, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Gappa M, Pillow JJ, Allen J, Mayer O, Stocks J. Lung function tests in neonates and infants with chronic lung disease: lung and chest-wall mechanics. Pediatr Pulmonol 2006; 41:291-317. [PMID: 16493664 DOI: 10.1002/ppul.20380] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This is the fifth paper in a review series that summarizes available data and critically discusses the potential role of lung function testing in infants and young children with acute neonatal respiratory disorders and chronic lung disease of infancy (CLDI). This review focuses on respiratory mechanics, including chest-wall and tissue mechanics, obtained in the intensive care setting and in infants during unassisted breathing. Following orientation of the reader to the subject area, we focused comments on areas of enquiry proposed in the introductory paper to this series. The quality of the published literature is reviewed critically with respect to relevant methods, equipment and study design, limitations and strengths of different techniques, and availability and appropriateness of reference data. Recommendations to guide future investigations in this field are provided. Numerous different methods have been used to assess respiratory mechanics with the aims of describing pulmonary status in preterm infants and assessing the effect of therapeutic interventions such as surfactant treatment, antenatal or postnatal steroids, or bronchodilator treatment. Interpretation of many of these studies is limited because lung volume was not measured simultaneously. In addition, populations are not comparable, and the number of infants studied has generally been small. Nevertheless, results appear to support the pathophysiological concept that immaturity of the lung leads to impaired lung function, which may improve with growth and development, irrespective of the diagnosis of chronic lung disease. To fully understand the impact of immaturity on the developing lung, it is unlikely that a single parameter such as respiratory compliance or resistance will accurately describe underlying changes. Assessment of respiratory mechanics will have to be supplemented by assessment of lung volume and airway function. New methods such as the low-frequency forced oscillation technique, which differentiate the tissue and airway components of respiratory mechanics, are likely to require further development before they can be of clinical significance.
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Affiliation(s)
- Monika Gappa
- Department of Pediatric Pulmonology and Neonatology, Medizinische Hochschule Hannover, Hannover, Germany.
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Pillow JJ, Frerichs I, Stocks J. Lung function tests in neonates and infants with chronic lung disease: global and regional ventilation inhomogeneity. Pediatr Pulmonol 2006; 41:105-21. [PMID: 16369918 DOI: 10.1002/ppul.20319] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This review considers measurement of global and regional ventilation inhomogeneity (VI) in infants and young children with acute neonatal respiratory disorders and chronic lung disease of infancy (CLDI). We focus primarily on multiple-breath inert gas washout (MBW) and electrical impedance tomography (EIT). The literature is critically reviewed and the relevant methods, equipment, and studies are summarized, including the limitations and strengths of individual techniques, together with the availability and appropriateness of any reference data. There has been a recent resurgence of interest in using MBW to monitor lung function within individuals and between different groups. In the mechanically ventilated, sedated, and paralyzed patient, VI indices can identify serial changes occurring following exogenous surfactant. Similarly, global VI indices appear to be increased in infants with CLDI and to differentiate between infants without lung disease and those with mild, moderate, and severe lung disease following preterm birth. While EIT is a relatively new technique, recent studies suggest that it is feasible in newborn infants, and can quantitatively identify changes in regional lung ventilation following alterations to ventilator settings, positive end expiratory pressure (PEEP), and administration of treatments such as surfactant. As such, EIT represents one of the more exciting prospects for continuous bedside pulmonary monitoring. For both techniques, there is an urgent need to establish guidelines regarding data collection, analysis, and interpretation in infants both with and without CLDI.
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Affiliation(s)
- J Jane Pillow
- Telethon Institute for Child Health Research, University of Western Australia, Perth, Western Australia, Australia.
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