1
|
Salvo V, Gazzolo D, Zimmermann LJ. The Complex Interrelationship Between Mechanical Ventilation and Therapeutic Hypothermia in Asphyxiated Newborns. A Review. Ther Hypothermia Temp Manag 2024; 14:80-88. [PMID: 37625025 DOI: 10.1089/ther.2023.0032] [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: 08/27/2023] Open
Abstract
Asphyxiated newborns often require both therapeutic hypothermia (TH) and mechanical ventilation (MV) and the complex interrelationship between these two therapeutic interventions is very interesting, which could not only have several synergistic positive effects but also some risks. Perinatal asphyxia is the leading cause of neonatal hypoxic-ischemic encephalopathy (HIE) and TH is the only approved neuroprotective treatment to limit brain injury, improving the mortality rate and long-term neurological outcomes. HIE is often associated with severe respiratory failure, requiring MV, due to different lung diseases or an impairment of the respiratory drive. The respiratory support management of asphyxiated newborns is very difficult, considering (a) various pathophysiological contexts, (b) the strong impact of TH on gas metabolism and (c) on lung mechanics, and (d) complex TH-MV interactions. Therefore, it is necessary to evaluate the real indications of MV for cooled newborns, considering the risks of respiratory overassistance (hypocapnia/hyperoxia), as well as the adequate monitoring systems. To date, specific randomized studies about the optimal respiratory approach for cooled newborns are lacking, and strategies for MV support vary from center to center. Moreover, there are many open questions about the real effects of cooling on lung mechanics and on surfactant, most appropriate method of blood gas analysis, and clear indications for pharmacological sedation. The aim of this review is to propose a reasoned approach for respiratory management of cooled newborns, considering the pathophysiological context, multiple actions of TH, and consequences of TH-MV matched action and its related risks.
Collapse
Affiliation(s)
- Vincenzo Salvo
- Mother and Child Health Department, Neonatal Intensive Care Unit, "Giovanni Paolo II" Hospital of Ragusa, ASP Ragusa, Italy
| | - Diego Gazzolo
- Neonatal Intensive Care Unit, "G. D'Annunzio" University, Chieti, Italy
| | - Luc J Zimmermann
- Department of Pediatrics and Neonatology, School for Oncology and Developmental Biology (GROW), Maastricht University Medical Center, Maastricht, The Netherlands
- European Foundation for the Care of Newborn Infants (EFCNI), München
| |
Collapse
|
2
|
Bezirganoglu H, Okur N, Buyuktiryaki M, Oguz SS, Dizdar EA, Sari FN. Comparison of Assist/Control Ventilation with and without Volume Guarantee in Term or Near-Term Infants. Am J Perinatol 2024; 41:e174-e179. [PMID: 35613941 DOI: 10.1055/a-1862-0078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
OBJECTIVES This study aimed to compare the effects of volume guarantee (VG) combined with assist/control (AC) ventilation to AC alone on hypocarbia episodes and extubation success in infants born at or near term. METHODS In this prospective cohort study, infants >34 weeks of gestation at birth, who were born in our hospital supported by synchronized, time-cycled, pressure limited, assist/control ventilation (AC) or assist-controlled VG mechanical ventilation (AC + VG) were included. After admission, infants received either AC or VG + AC using by Leoni Plus ventilator. The ventilation mode was left to the clinician. In the AC group, peak airway pressure was set clinically. In the VG + AC group, desired tidal volume was set at 5 mL/kg, with the ventilator adjusting peak inspiratory pressure to deliver this volume. The study was completed once the patient extubated. RESULTS There were 35 patients in each group. Incidence of hypocarbia was lower in the VG + AC compared with AC (%17.1 and 22.8%, respectively) but statistically not significant. Out-of-range partial pressure of carbon dioxide (PCO2) levels were lower in the VG + AC group and it reached borderline statistical significance (p = 0.06). The median extubation time was 70 (42-110) hours in the VG + AC group, 89.5 (48.5-115.5) hours in the AC group, and it did not differ between groups (p = 0.47). CONCLUSION We found combining AC and VG ventilation compared with AC ventilation alone yielded similar hypocarbia episodes and extubation time for infants of >34 gestational weeks with borderline significance lower out-of-range PCO2 incidence. KEY POINTS · Underlying lung pathology requiring mechanical ventilation support in term infant is heterogeneous.. · VG ventilation compared with conventional modes yielded similar hypocarbia episodes in term infants.. · Combining VG ventilation lead to borderline significance lower out-of-range PCO2 incidence..
Collapse
Affiliation(s)
- Handan Bezirganoglu
- Division of Neonatology, Department of Pediatrics, University of Health Sciences, Ankara City Hospital, Ankara, Türkiye
- Division of Neonatology, Trabzon Kanuni Training and Research Hospital, Trabzon, Türkiye
| | - Nilufer Okur
- Division of Neonatology, Department of Pediatrics, University of Health Sciences, Ankara City Hospital, Ankara, Türkiye
- Division of Neonatology, Diyarbakir Gazi Yasargil Training and Research Hospital, Diyarbakir, Türkiye
| | - Mehmet Buyuktiryaki
- Division of Neonatology, Department of Pediatrics, University of Health Sciences, Ankara City Hospital, Ankara, Türkiye
- Division of Neonatology, Department of Pediatrics, İstanbul Medipol University Medical School, İstanbul, Türkiye
| | - Serife S Oguz
- Division of Neonatology, Department of Pediatrics, University of Health Sciences, Ankara City Hospital, Ankara, Türkiye
| | - Evrim A Dizdar
- Division of Neonatology, Department of Pediatrics, University of Health Sciences, Ankara City Hospital, Ankara, Türkiye
| | - Fatma N Sari
- Division of Neonatology, Department of Pediatrics, University of Health Sciences, Ankara City Hospital, Ankara, Türkiye
| |
Collapse
|
3
|
Silvera F, Gagliardi T, Vollono P, Fernández C, García-Bayce A, Berardi A, Badía M, Beltrán B, Cabral T, Abella P, Farías L, Vaamonde L, Martell M, Blasina F. Study of the relationship between regional cerebral saturation and pCO2 changes during mechanical ventilation to evaluate modifications in cerebral perfusion in a newborn piglet model. Braz J Med Biol Res 2022; 55:e11543. [PMID: 35239775 PMCID: PMC8905677 DOI: 10.1590/1414-431x2022e11543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Accepted: 01/04/2022] [Indexed: 11/22/2022] Open
Abstract
Near-infrared spectroscopy (NIRS) could be a useful continuous, non-invasive technique for monitoring the effect of partial pressure of carbon dioxide (PaCO2) fluctuations in the cerebral circulation during ventilation. The aim of this study was to examine the efficacy of NIRS to detect acute changes in cerebral blood flow following PaCO2 fluctuations after confirming the autoregulation physiology in piglets. Fourteen piglets (<72 h of life) were studied. Mean arterial blood pressure, oxygen saturation, pH, glycemia, hemoglobin, electrolytes, and temperature were monitored. Eight animals were used to evaluate brain autoregulation, assessing superior cava vein Doppler as a proxy of cerebral blood flow changing mean arterial blood pressure. Another 6 animals were used to assess hypercapnia generated by decreasing ventilatory settings and complementary CO2 through the ventilator circuit and hypocapnia due to increasing ventilatory settings. Cerebral blood flow was determined by jugular vein blood flow by Doppler and continuously monitored with NIRS. A decrease in PaCO2 was observed after hyperventilation (47.6±2.4 to 29.0±4.9 mmHg). An increase in PaCO2 was observed after hypoventilation (48.5±5.5 to 90.4±25.1 mmHg). A decrease in cerebral blood flow after hyperventilation (21.8±10.4 to 15.1±11.0 mL/min) and an increase after hypoventilation (23.4±8.4 to 38.3±10.5 mL/min) were detected by Doppler ultrasound. A significant correlation was found between cerebral oxygenation and Doppler-derived parameters of blood flow and PaCO2. Although cerebral NIRS monitoring is mainly used to detect changes in regional brain oxygenation, modifications in cerebral blood flow following experimental PaCO2 changes were detected in newborn piglets when no other important variables were modified.
Collapse
Affiliation(s)
- F Silvera
- Department of Neonatology, Centro Hospitalario Pereira Rossell, Administración de los Servicios de Salud del Estado, and Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - T Gagliardi
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - P Vollono
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - C Fernández
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - A García-Bayce
- Division of Pediatric Imagenology, Centro Hospitalario Pereira Rossell, Administración de los Servicios de Salud del Estado, and Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - A Berardi
- Department of Neonatology, Centro Hospitalario Pereira Rossell, Administración de los Servicios de Salud del Estado, and Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - M Badía
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - B Beltrán
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - T Cabral
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - P Abella
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - L Farías
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - L Vaamonde
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - M Martell
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| | - F Blasina
- Department of Neonatology, Hospital de Clínicas Dr. Manuel Quintela, Faculty of Medicine, Republic University, Montevideo, Uruguay
| |
Collapse
|
4
|
Carbon dioxide levels in neonates: what are safe parameters? Pediatr Res 2022; 91:1049-1056. [PMID: 34230621 PMCID: PMC9122818 DOI: 10.1038/s41390-021-01473-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 03/01/2021] [Accepted: 03/02/2021] [Indexed: 02/01/2023]
Abstract
There is no consensus on the optimal pCO2 levels in the newborn. We reviewed the effects of hypercapnia and hypocapnia and existing carbon dioxide thresholds in neonates. A systematic review was conducted in accordance with the PRISMA statement and MOOSE guidelines. Two hundred and ninety-nine studies were screened and 37 studies included. Covidence online software was employed to streamline relevant articles. Hypocapnia was associated with predominantly neurological side effects while hypercapnia was linked with neurological, respiratory and gastrointestinal outcomes and Retinpathy of prematurity (ROP). Permissive hypercapnia did not decrease periventricular leukomalacia (PVL), ROP, hydrocephalus or air leaks. As safe pCO2 ranges were not explicitly concluded in the studies chosen, it was indirectly extrapolated with reference to pCO2 levels that were found to increase the risk of neonatal disease. Although PaCO2 ranges were reported from 2.6 to 8.7 kPa (19.5-64.3 mmHg) in both term and preterm infants, there are little data on the safety of these ranges. For permissive hypercapnia, parameters described for bronchopulmonary dysplasia (BPD; PaCO2 6.0-7.3 kPa: 45.0-54.8 mmHg) and congenital diaphragmatic hernia (CDH; PaCO2 ≤ 8.7 kPa: ≤65.3 mmHg) were identified. Contradictory findings on the effectiveness of permissive hypercapnia highlight the need for further data on appropriate CO2 parameters and correlation with outcomes. IMPACT: There is no consensus on the optimal pCO2 levels in the newborn. There is no consensus on the effectiveness of permissive hypercapnia in neonates. A safe range of pCO2 of 5-7 kPa was inferred following systematic review.
Collapse
|
5
|
Accounting for arterial and capillary blood gases for calculation of cerebral blood flow in preterm infants. Eur J Pediatr 2022; 181:2087-2096. [PMID: 35150310 PMCID: PMC9056440 DOI: 10.1007/s00431-022-04392-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 01/14/2022] [Accepted: 01/22/2022] [Indexed: 12/04/2022]
Abstract
UNLABELLED One of the most feared neurological complications of premature birth is intraventricular hemorrhage, frequently triggered by fluctuations in cerebral blood flow (CBF). Although several techniques for CBF measurement have been developed, they are not part of clinical routine in neonatal intensive care. A promising tool for monitoring of CBF is its numerical assessment using standard clinical parameters such as mean arterial pressure, carbon dioxide partial pressure (pCO2) and oxygen partial pressure (pO2). A standard blood gas analysis is performed on arterial blood. In neonates, capillary blood is widely used for analysis of blood gas parameters. The purpose of this study was the assessment of differences between arterial and capillary analysis of blood gases and adjustment of the mathematical model for CBF calculation to capillary values. The statistical analysis of pCO2 and pO2 values collected from 254 preterm infants with a gestational age of 23-30 weeks revealed no significant differences between arterial and capillary pCO2 and significantly lower values for capillary pO2. The estimated mean differences between arterial and capillary pO2 of 15.15 mmHg (2.02 kPa) resulted in a significantly higher CBF calculated for capillary pO2 compared to CBF calculated for arterial pO2. Two methods for correction of capillary pO2 were proposed and compared, one based on the mean difference and another one based on a regression model. CONCLUSION Capillary blood gas analysis with correction for pO2 as proposed in the present work is an acceptable alternative to arterial sampling for the assessment of CBF. WHAT IS KNOWN • Arterial blood analysis is the gold standard in clinical practice. However, capillary blood is widely used for estimating blood gas parameters. • There is no significant difference between the arterial and capillary pCO2 values, but the capillary pO2 differs significantly from the arterial one. WHAT IS NEW • The lower capillary pO2 values yield significantly higher values of calculated CBF compared to CBF computed from arterial pO2 measurements. • Two correction methods for the adjustment of capillary pO2 to arterial pO2 that made the difference in the calculated CBF insignificant have been proposed.
Collapse
|
6
|
Effect of Permissive Mild Hypercapnia on Cerebral Vasoreactivity in Infants: A Randomized Controlled Crossover Trial. Anesth Analg 2021; 133:976-983. [PMID: 33410612 DOI: 10.1213/ane.0000000000005325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Mechanical ventilation interferes with cerebral perfusion via changes in intrathoracic pressure and/or as a consequence of alterations in CO2. Cerebral vascular vasoreactivity is dependent on CO2, and hypocapnia can potentially lead to vasoconstriction and subsequent decrease in cerebral blood flow. Thus, we aimed at characterizing whether protective ventilation with mild permissive hypercapnia improves cerebral perfusion in infants. METHODS Following ethical approval and parental consent, 19 infants were included in this crossover study and randomly assigned to 2 groups for which the initial ventilation parameters were set to achieve an end-tidal carbon dioxide (Etco2) of 6.5 kPa (group H: mild hypercapnia, n = 8) or 5.5 kPa (group N: normocapnia, n = 11). The threshold was then reversed before going back to the initial set value of normo- or hypercapnia. At each step, hemodynamic, respiratory, and near-infrared spectroscopy (NIRS)-derived parameters, including tissue oxygenation index (TOI) and tissue hemoglobin index (THI), concentration of deoxygenated hemoglobin (HHb) and oxygenated hemoglobin (O2Hb), were collected. Concomitantly, sevoflurane maintenance concentration, ventilatory (driving pressure) and hemodynamic parameters, as mean arterial pressure (MAP), were recorded. RESULTS Targeting an Etco2 of 5.5 kPa resulted in significantly higher mean driving pressure than an Etco2 of 6.5 kPa (P < .01) with no difference between the groups in end-tidal sevoflurane, MAP, and heart rate. A large scatter was observed in NIRS-derived parameters, with no evidence for difference in Etco2 changes between or within groups. A mild decrease with time was observed in THI and MAP in infants randomly assigned to group N (P < .036 and P < .017, respectively). When pooling all groups together, a significant correlation was found between the changes in MAP and TOI (r = 0.481, P < .001). CONCLUSIONS Allowing permissive mild hypercapnia during mechanical ventilation of infants led to lower driving pressure and comparable hemodynamic, respiratory, and cerebral oxygenation parameters than during normocapnia. Whereas a large scatter in NIRS-derived parameters was observed at all levels of Etco2, the correlation between TOI and MAP suggests that arterial pressure is an important component of cerebral oxygenation at mild hypercapnia.
Collapse
|
7
|
Usuda H, Watanabe S, Miura Y, Saito M, Musk GC, Rittenschober-Böhm J, Ikeda H, Sato S, Hanita T, Matsuda T, Jobe AH, Newnham JP, Stock SJ, Kemp MW. Successful maintenance of key physiological parameters in preterm lambs treated with ex vivo uterine environment therapy for a period of 1 week. Am J Obstet Gynecol 2017. [PMID: 28646647 DOI: 10.1016/j.ajog.2017.05.046] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Extremely preterm infants born at the border of viability (22-24 weeks' gestation) have high rates of death and lasting disability. Ex vivo uterine environment therapy is an experimental neonatal intensive care strategy that provides gas exchange using parallel membranous oxygenators connected to the umbilical vessels, sparing the extremely preterm cardiopulmonary system from ventilation-derived injury. OBJECTIVE In this study, we aimed to refine our ex vivo uterine environment therapy platform to eliminate fetal infection and inflammation, while simultaneously extending the duration of hemodynamically stable ex vivo uterine environment therapy to 1 week. STUDY DESIGN Merino-cross ewes with timed, singleton pregnancies were surgically delivered at 112-115 days of gestation (term is ∼150 days) and adapted to ex vivo uterine environment therapy (treatment group; n = 6). Physiological variables were continuously monitored; humerus and femur length, ductus arteriosus directional flow, and patency were estimated with ultrasound; serial blood samples were collected for hematology and microbiology studies; weight was recorded at the end of the experiment. Control group animals (n = 7) were euthanized at 122 days of gestation and analyzed accordingly. Bacteremia was defined by positive blood culture. Infection and fetal inflammation was assessed with white blood cell counts (including differential leukocyte counts), plasma and lung proinflammatory cytokine measurements, and lung histopathology. RESULTS Five of 6 fetuses in the treatment group completed the 1-week study period with key physiological parameters, blood counts remaining within normal ranges, and no bacteremia detected. There were no significant differences (P > .05) in arterial blood oxygen content or lactate levels between ex vivo uterine environment therapy and control groups at delivery. There was no significant difference (P > .05) in birthweight between control and ex vivo uterine environment groups. In the ex vivo uterine environment group, we observed growth of fetal humerus (P < .05) and femur (P < .001) over the course of the 7-day experimental period. There was no difference in airway or airspace morphology or consolidation between control and ex vivo uterine environment animals, and there was no increase in the number of lung cells staining positive for T-cell marker CD3+. CONCLUSION Five preterm lambs were maintained in a physiologically stable condition for 1 week with significant growth and without clinically significant bacteremia or systemic inflammation. Although substantial further refinement is required, a life support platform based around ex vivo uterine environment therapy may provide an avenue to improve outcomes for extremely preterm infants.
Collapse
Affiliation(s)
- Haruo Usuda
- Division of Obstetrics and Gynecology, University of Western Australia, Crawley, Australia; Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan.
| | - Shimpei Watanabe
- Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Yuichiro Miura
- Division of Obstetrics and Gynecology, University of Western Australia, Crawley, Australia; Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Masatoshi Saito
- Division of Obstetrics and Gynecology, University of Western Australia, Crawley, Australia; Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Gabrielle C Musk
- Animal Care Services, University of Western Australia, Crawley, Australia
| | - Judith Rittenschober-Böhm
- Division of Obstetrics and Gynecology, University of Western Australia, Crawley, Australia; Division of Neonatology, Pediatric Intensive Care and Neuropediatrics, Medical University of Vienna, Vienna, Austria
| | - Hideyuki Ikeda
- Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Shinichi Sato
- Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Takushi Hanita
- Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Tadashi Matsuda
- Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Alan H Jobe
- Neonatology Continuing Medical Education Global Health Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - John P Newnham
- Division of Obstetrics and Gynecology, University of Western Australia, Crawley, Australia
| | - Sarah J Stock
- Division of Obstetrics and Gynecology, University of Western Australia, Crawley, Australia; Tommy's Center for Maternal and Fetal Health, MRC Center for Reproductive Health, University of Edinburgh Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Matthew W Kemp
- Division of Obstetrics and Gynecology, University of Western Australia, Crawley, Australia; Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| |
Collapse
|
8
|
Dix LML, Weeke LC, de Vries LS, Groenendaal F, Baerts W, van Bel F, Lemmers PMA. Carbon Dioxide Fluctuations Are Associated with Changes in Cerebral Oxygenation and Electrical Activity in Infants Born Preterm. J Pediatr 2017; 187:66-72.e1. [PMID: 28578157 DOI: 10.1016/j.jpeds.2017.04.043] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 04/05/2017] [Accepted: 04/20/2017] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To evaluate the effects of acute arterial carbon dioxide partial pressure changes on cerebral oxygenation and electrical activity in infants born preterm. STUDY DESIGN This retrospective observational study included ventilated infants born preterm with acute fluctuations of continuous end-tidal CO2 (etCO2) as a surrogate marker for arterial carbon dioxide partial pressure, during the first 72 hours of life. Regional cerebral oxygen saturation and fractional tissue oxygen extraction were monitored with near-infrared spectroscopy. Brain activity was monitored with 2-channel electroencephalography. Spontaneous activity transients (SATs) rate (SATs/minute) and interval between SATs (in seconds) were calculated. Ten-minute periods were selected for analysis: before, during, and after etCO2 fluctuations of ≥5 mm Hg. RESULTS Thirty-eight patients (mean ± SD gestational age of 29 ± 1.8 weeks) were included, with 60 episodes of etCO2 increase and 70 episodes of etCO2 decrease. During etCO2 increases, brain oxygenation increased (regional cerebral oxygen saturation increased, fractional tissue oxygen extraction decreased; P < .01) and electrical activity decreased (SATs/minute decreased, interval between SATs increased; P < .01). All measures recovered when etCO2 returned to baseline. During etCO2 decreases, brain oxygenation decreased (regional cerebral oxygen saturation decreased, fractional tissue oxygen extraction decreased; P < .01) and brain activity increased (SATs/minute increased, P < .05), also with recovery after return of etCO2 to baseline. CONCLUSION An acute increase in etCO2 is associated with increased cerebral oxygenation and decreased brain activity, whereas an acute decrease is associated with decreased cerebral oxygenation and slightly increased brain activity. Combining continuous CO2 monitoring with near-infrared spectroscopy may enable the detection of otherwise undetected fluctuations in arterial carbon dioxide partial pressure that may be harmful to the neonatal brain.
Collapse
Affiliation(s)
- Laura Marie Louise Dix
- Department of Neonatology, Wilhelmina Children's Hospital/University Medical Center Utrecht, The Netherlands
| | - Lauren Carleen Weeke
- Department of Neonatology, Wilhelmina Children's Hospital/University Medical Center Utrecht, The Netherlands
| | - Linda Simone de Vries
- Department of Neonatology, Wilhelmina Children's Hospital/University Medical Center Utrecht, The Netherlands
| | - Floris Groenendaal
- Department of Neonatology, Wilhelmina Children's Hospital/University Medical Center Utrecht, The Netherlands
| | - Willem Baerts
- Department of Neonatology, Wilhelmina Children's Hospital/University Medical Center Utrecht, The Netherlands
| | - Frank van Bel
- Department of Neonatology, Wilhelmina Children's Hospital/University Medical Center Utrecht, The Netherlands
| | - Petra Maria Anna Lemmers
- Department of Neonatology, Wilhelmina Children's Hospital/University Medical Center Utrecht, The Netherlands.
| |
Collapse
|
9
|
Simpao AF, Ahumada LM, Gálvez JA, Bonafide CP, Wartman EC, Randall England W, Lingappan AM, Kilbaugh TJ, Jawad AF, Rehman MA. The timing and prevalence of intraoperative hypotension in infants undergoing laparoscopic pyloromyotomy at a tertiary pediatric hospital. Paediatr Anaesth 2017; 27:66-76. [PMID: 27896911 DOI: 10.1111/pan.13036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/11/2016] [Indexed: 11/28/2022]
Abstract
BACKGROUND Intraoperative hypotension may be associated with adverse outcomes in children undergoing surgery. Infants and neonates under 6 months of age have less autoregulatory cerebral reserve than older infants, yet little information exists regarding when and how often intraoperative hypotension occurs in infants. AIMS To better understand the epidemiology of intraoperative hypotension in infants, we aimed to determine the prevalence of intraoperative hypotension in a generally uniform population of infants undergoing laparoscopic pyloromyotomy. METHODS Vital sign data from electronic records of infants who underwent laparoscopic pyloromyotomy with general anesthesia at a children's hospital between January 1, 1998 and October 4, 2013 were analyzed. Baseline blood pressure (BP) values and intraoperative BPs were identified during eight perioperative stages based on anesthesia event timestamps. We determined the occurrence of relative (systolic BP <20% below baseline) and absolute (mean arterial BP <35 mmHg) intraoperative hypotension within each stage. RESULTS A total of 735 full-term infants and 82 preterm infants met the study criteria. Relative intraoperative hypotension occurred in 77%, 72%, and 58% of infants in the 1-30, 31-60, and 61-90 days age groups, respectively. Absolute intraoperative hypotension was seen in 21%, 12%, and 4% of infants in the 1-30, 31-60, and 61-90 days age groups, respectively. Intraoperative hypotension occurred primarily during surgical prep and throughout the surgical procedure. Preterm infants had higher rates of absolute intraoperative hypotension than full-term infants. CONCLUSIONS Relative intraoperative hypotension was routine and absolute intraoperative hypotension was common in neonates and infants under 91 days of age. Preterm infants and infants under 61 days of age experienced the highest rates of absolute and relative intraoperative hypotension, particularly during surgical prep and throughout surgery.
Collapse
Affiliation(s)
- Allan F Simpao
- Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine at the University of Pennsylvania and The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Luis M Ahumada
- Data Analytics and Enterprise Reporting, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jorge A Gálvez
- Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine at the University of Pennsylvania and The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Christopher P Bonafide
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania and the Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Elicia C Wartman
- Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - William Randall England
- Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Arul M Lingappan
- Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine at the University of Pennsylvania and The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Todd J Kilbaugh
- Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine at the University of Pennsylvania and The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Abbas F Jawad
- Department of Biostatistics in Pediatrics, Perelman School of Medicine at the University of Pennsylvania and the Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Mohamed A Rehman
- Department of Anesthesiology and Critical Care Medicine, Perelman School of Medicine at the University of Pennsylvania and The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| |
Collapse
|
10
|
Ringer SK, Ohlerth S, Carrera I, Mauch J, Spielmann N, Bettschart-Wolfensberger R, Weiss M. Effects of hypotension and/or hypocapnia during sevoflurane anesthesia on perfusion and metabolites in the developing brain of piglets-a blinded randomized study. Paediatr Anaesth 2016; 26:909-18. [PMID: 27345010 DOI: 10.1111/pan.12956] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/27/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Hypotension (HT) and/or hypocapnia (HC) are frequent complications occurring during pediatric anesthesia and may cause cerebral injury in the developing brain. AIM The aim of this study is to investigate the effects of HT and/or HC on perfusion and metabolism in the developing brain. METHODS Twenty-eight piglets were randomly allocated to four groups: control (C), HT, HC, and hypotension and hyocapnia (HTC). Anesthesia was induced and maintained using sevoflurane. Fentanyl was added for instrumentation. Piglets were fully monitored and their lungs were artificially ventilated. Before treatment, conventional magnetic resonance imaging (MRI), dynamic susceptibility-contrast-enhanced T2*-weighted MRI (DSC-MRI), and single voxel proton MR spectroscopy ((1) H MRS) were performed. Hypotension (mean arterial blood pressure: 30 ± 3 mmHg) was induced by blood withdrawal and nitroprusside infusion, and hyperventilation was used to induce HC (PaCO2 : 2.7-3.3 kPa). (1) H MRS and DSC-MRI were repeated immediately once treatment goals were achieved and 120 min later. Radiologists were blinded to the groups. DSCI-MRI and (1) H MRS analyses were performed in the thalamus, occipital and parietal lobe, hippocampus, and watershed areas. RESULTS In comparison to C, mean time to peak (TTP) increased with HTC in all brain areas as assessed with DSC-MRI (n = 26). Using (1) H MRS, a significant decrease in N-acetyl aspartate, choline, and myoinositol, as well as an increase in glutamine-glutamate complex (Glx) were detected independent of group. Compared to C, changes were more pronounced for Glx (due to an increase in glutamate) and myoinositol with HTC, for N-acetyl aspartate with HT, and for Glx with HC. No lactate signal was present. CONCLUSIONS The combination of HT and HC during sevoflurane anesthesia resulted in alteration of cerebral perfusion with signs of neuronal dysfunction and early neuronal ischemia. HT and HC alone also resulted in signs of metabolic disturbances despite the absence of detectable cerebral perfusion alterations.
Collapse
Affiliation(s)
- Simone K Ringer
- Section Anesthesiology, Equine Department, Vetsuisse Faculty University of Zurich, Zurich, Switzerland
| | - Stefanie Ohlerth
- Department for Small Animals, Clinic of Diagnostic Imaging, Vetsuisse Faculty University of Zurich, Zurich, Switzerland
| | - Inés Carrera
- Department for Small Animals, Clinic of Diagnostic Imaging, Vetsuisse Faculty University of Zurich, Zurich, Switzerland
| | - Jacqueline Mauch
- Department of Anesthesiology, Luzerner Kantonsspital, Lucerne, Switzerland
| | - Nelly Spielmann
- Department of Anesthesia, University Children's Hospital Zurich, Zurich, Switzerland.,Children's Research Center, University Children's Hospital of Zurich, University of Zurich, Zurich, Switzerland
| | | | - Markus Weiss
- Department of Anesthesia, University Children's Hospital Zurich, Zurich, Switzerland.,Children's Research Center, University Children's Hospital of Zurich, University of Zurich, Zurich, Switzerland
| |
Collapse
|
11
|
Estrategias de ventilación a favor de la neuroprotección: ¿qué podemos hacer? PERINATOLOGÍA Y REPRODUCCIÓN HUMANA 2016. [DOI: 10.1016/j.rprh.2016.10.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
12
|
Ma J, Ye H. Effects of permissive hypercapnia on pulmonary and neurodevelopmental sequelae in extremely low birth weight infants: a meta-analysis. SPRINGERPLUS 2016; 5:764. [PMID: 27386250 PMCID: PMC4912505 DOI: 10.1186/s40064-016-2437-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/27/2016] [Indexed: 11/17/2022]
Abstract
Objectives To perform a systematic review and meta-analysis of the efficacy and safety of permissive hypercapnia in extremely low birth weight infants. Methods A systematic search of MEDLINE, EMBASE, the Cochrane Database of randomized trials. Eligibility and quality of trials were assessed, and data on study design, patient characteristics, and relevant outcomes were extracted. Results Four studies that enrolled a total of 693 participants were selected. Meta-analysis revealed no effect of permissive hypercapnia on decreasing rates of bronchopulmonary dysplasia (BPD). Permissive hypercapnia also had no significant effect on mortality, intraventricular haemorrhage (IVH), IVH (grade 3–4), periventricular leukomalacia (PVL), necrotising enterocolitis (NEC), retinopathy of prematurity (ROP) or air leaks in extremely low birth weight infants. Neurodevelopmental outcomes were comparable at 18–22 months’ corrected age in two studies. permissive hypercapnia did not increase the risk of cerebral palsy, Mental Developmental Index <70, Psychomotor Developmental Index <70, visual deficit, or hearing deficit. Conclusions Permissive hypercapnia did not reduce the rate of BPD in extremely low birth weight infants. The rates of mortality, IVH, PVL, NEC, ROP and neurodevelopmental outcomes did not differ between these two groups. These results suggest that permissive hypercapnia does not bring extra benefits in extremely low birth weight infants.
Collapse
Affiliation(s)
- Jianglin Ma
- Department of Pediatrics, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310000 People's Republic of China
| | - Hui Ye
- Department of Pediatrics, Taizhou First People's Hospital, Taizhou, 318020 People's Republic of China
| |
Collapse
|
13
|
Kugelman A, Bromiker R, Riskin A, Shoris I, Ronen M, Qumqam N, Bader D, Golan A. Diagnostic accuracy of capnography during high-frequency ventilation in neonatal intensive care units. Pediatr Pulmonol 2016; 51:510-6. [PMID: 26422449 DOI: 10.1002/ppul.23319] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 08/10/2015] [Accepted: 09/07/2015] [Indexed: 01/09/2023]
Abstract
BACKGROUND AND OBJECTIVE High-frequency ventilation (HFV) is a powerful tool for CO2 elimination, and thus requires careful monitoring of CO2 . Our aim was to assess the diagnostic accuracy (correlation, agreement, and trending) of continuous distal capnography (dCap) with PaCO2 in infants ventilated with HFV. DESIGN This was a prospective, observational, multicenter study. dCap was compared with simultaneous PaCO2 ("gold standard") drawn from indwelling arterial line for patient care in term and preterm infants ventilated with HFV. dCap was obtained via the side-port of a double-lumen endotracheal-tube by a Microstream capnograph with specially designed software for HFV. RESULTS Twenty-four infants participated in the study (median [range] gestational age [GA]: 26.8 [23.6-38.6] weeks). Analysis included 332 measurements. dCap was in correlation (r = 0.70, P < 0.001) but with less than adequate agreement (mean difference ± SD of the differences: -11.7 ± 10.3 mmHg) with PaCO2 . Comparable findings were found in the subgroup of infants <1,000 g (n = 240 measurements). Correlations were maintained in severe lung disease. Changes in dCap and in PaCO2 for consecutive measurements within each patient were correlated (r = 0.63, P < 0.001). Area under the receiver operating curves (ROC) for dCap to detect high (>60 mmHg) or low (<30 mmHg) PaCO2 was 0.83 (CI: 0.76-0.90) and 0.88 (CI: 0.79-0.97), respectively; P < 0.001. CONCLUSIONS Our prospective study suggests that continuous dCap in infants ventilated with HFV may be helpful for trends and alarm for unsafe levels of PaCO2 . dCap is only a complimentary tool and cannot replace PaCO2 sampling because the agreement between these measurements was less than adequate.
Collapse
Affiliation(s)
- Amir Kugelman
- Department of Neonatology, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel.,Pediatric Pulmonary Unit, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Ruben Bromiker
- Department of Neonatology, Shaare Zedek Medical Center, Faculty of Medicine of the Hebrew University, Jerusalem, Israel
| | - Arieh Riskin
- Department of Neonatology, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Irit Shoris
- Department of Neonatology, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Michal Ronen
- Covidien, Respiratory and Monitoring Solutions, Jerusalem, Israel
| | - Nelly Qumqam
- Department of Neonatology, Shaare Zedek Medical Center, Faculty of Medicine of the Hebrew University, Jerusalem, Israel
| | - David Bader
- Department of Neonatology, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Agenta Golan
- Department of Neonatology, Soroka Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| |
Collapse
|
14
|
Bruschettini M, Romantsik O, Zappettini S, Ramenghi LA, Calevo MG. Transcutaneous carbon dioxide monitoring for the prevention of neonatal morbidity and mortality. Cochrane Database Syst Rev 2016; 2:CD011494. [PMID: 26874180 PMCID: PMC8720274 DOI: 10.1002/14651858.cd011494.pub2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Carbon dioxide (CO2) measurement is a fundamental evaluation in a neonatal intensive care unit (NICU), as both low and high values of CO2 might have detrimental effects on neonatal morbidity and mortality. Though measurement of CO2 in the arterial blood gas is the most accurate way to assess the amount of CO2, it requires blood sampling and it does not provide a continuous monitoring of CO2. OBJECTIVES To assess whether the use of continuous transcutaneous CO2 (tcCO2) monitoring in newborn infants reduces mortality and improves short and long term respiratory and neurodevelopmental outcomes. SEARCH METHODS We used the standard search strategy of the Cochrane Neonatal Review group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 11), MEDLINE via PubMed (1966 to November 1, 2015), EMBASE (1980 to November 1, 2015), and CINAHL (1982 to November 1, 2015). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomized controlled trials and quasi-randomized trials. SELECTION CRITERIA Randomized, quasi-randomized and cluster randomized controlled trials comparing different strategies regarding tcCO2 monitoring in newborns. Three comparisons were considered, that is, continuous tcCO2 monitoring versus 1) any intermittent modalities to measure CO2; 2) other continuous CO2 monitoring; and 3) with or without intermittent CO2 monitoring. DATA COLLECTION AND ANALYSIS We used the standard methods of the Cochrane Neonatal Review Group. Two review authors independently assessed studies identified by the search strategy for inclusion. MAIN RESULTS Our search strategy yielded 106 references. Two review authors independently assessed all references for inclusion. We did not find any completed studies for inclusion, nor ongoing trials. AUTHORS' CONCLUSIONS There was no evidence to recommend or refute the use of transcutaneous CO2 monitoring in neonates. Well-designed, adequately powered randomized controlled studies are necessary to address efficacy and safety of transcutaneous CO2 monitoring in neonates.
Collapse
Affiliation(s)
- Matteo Bruschettini
- Institute for Clinical Sciences, Lund UniversityDepartment of PediatricsLundSweden21185
| | - Olga Romantsik
- Institute for Clinical Sciences, Lund UniversityDepartment of PediatricsLundSweden21185
| | | | | | - Maria Grazia Calevo
- Istituto Giannina GasliniEpidemiology, Biostatistics and Committees UnitGenoaItaly16147
| | | |
Collapse
|
15
|
Kugelman A, Golan A, Riskin A, Shoris I, Ronen M, Qumqam N, Bader D, Bromiker R. Impact of Continuous Capnography in Ventilated Neonates: A Randomized, Multicenter Study. J Pediatr 2016; 168:56-61.e2. [PMID: 26490126 DOI: 10.1016/j.jpeds.2015.09.051] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 08/31/2015] [Accepted: 09/15/2015] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To compare the time spent within a predefined safe range of CO2 (30-60 mmHg) during conventional ventilation between infants who were monitored with distal end-tidal CO2 (dETCO2, or capnography) and those who were not. STUDY DESIGN For this randomized, controlled multicenter study, ventilated infants with a double-lumen endotracheal tube were randomized to 1 of 2 groups: the open (monitored) group, in which data from the capnograph were recorded, displayed to the medical team, and used for patient care, and the masked group, in which data from the capnograph were recorded. However, the measurements were masked and not available for patient care. dETCO2 was compared with PaCO2 measurements recorded for patient care. RESULTS Fifty-five infants (25 open, 30 masked) participated in the study (median gestational age, 28.6 weeks; range, 23.5-39.0 weeks). The 2 groups were comparable. dETCO2 was in good correlation (r = 0.73; P < .001) and adequate agreement (mean ± SD of the difference, 3.0 ± 8.5 mmHg) with PaCO2. Compared with infants in the masked group, those in the monitored group had significantly (P = .03) less time with an unsafe dETCO2 level (high: 3.8% vs 8.8% or low: 3.8% vs 8.9%). The prevalence of intraventricular hemorrhage or periventricular leukomalacia rate was lower in the monitored group (P = .02) and was significantly (P < .05) associated with the independent factors dETCO2 monitoring and gestational age. CONCLUSION Continuous dETCO2 monitoring improved control of CO2 levels within a safe range during conventional ventilation in a neonatal intensive care unit. TRIAL REGISTRATION ClinicalTrials.gov: NCT01572272.
Collapse
Affiliation(s)
- Amir Kugelman
- Department of Neonatology, Bnai Zion Medical Center, The Ruth and Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel; Pediatric Pulmonary Unit, Bnai Zion Medical Center, The Ruth and Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel.
| | - Agenta Golan
- Department of Neonatology, Soroka Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Arieh Riskin
- Department of Neonatology, Bnai Zion Medical Center, The Ruth and Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Irit Shoris
- Department of Neonatology, Bnai Zion Medical Center, The Ruth and Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Michal Ronen
- Department of Research and Development, Covidien Respiratory and Monitoring Solutions, Jerusalem, Israel
| | - Nelly Qumqam
- Department of Neonatology, Shaare Zedek Medical Center, Faculty of Medicine, Hebrew University, Jerusalem, Israel
| | - David Bader
- Department of Neonatology, Bnai Zion Medical Center, The Ruth and Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Ruben Bromiker
- Department of Neonatology, Shaare Zedek Medical Center, Faculty of Medicine, Hebrew University, Jerusalem, Israel
| |
Collapse
|
16
|
Hwang JH. Optimal Ventilatory Strategies in Preterm Infants: Permissive Hypercapnia. NEONATAL MEDICINE 2014. [DOI: 10.5385/nm.2014.21.2.114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Affiliation(s)
- Jong Hee Hwang
- Department of Pediatrics, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Korea
| |
Collapse
|
17
|
Abstract
Breathing movements have been demonstrated in the fetuses of every mammalian species investigated and are a critical component of normal fetal development. The classic sheep preparations instrumented for chronic fetal monitoring determined that fetal breathing movements (FBMs) occur in aggregates interspersed with long periods of quiescence that are strongly associated with neurophysiological state. The fetal sheep model also provided data regarding the neurochemical modulation of behavioral state and FBMs under a variety of in utero conditions. Subsequently, in vitro rodent models have been developed to advance our understanding of cellular, synaptic, network, and more detailed neuropharmacological aspects of perinatal respiratory neural control. This includes the ontogeny of the inspiratory rhythm generating center, the preBötzinger complex (preBötC), and the anatomical and functional development of phrenic motoneurons (PMNs) and diaphragm during the perinatal period. A variety of newborn animal models and studies of human infants have provided insights into age-dependent changes in state-dependent respiratory control, responses to hypoxia/hypercapnia and respiratory pathologies.
Collapse
Affiliation(s)
- John J Greer
- Department of Physiology, Centre for Neuroscience, Women and Children Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.
| |
Collapse
|
18
|
Kasdorf E, Perlman JM. Strategies to prevent reperfusion injury to the brain following intrapartum hypoxia-ischemia. Semin Fetal Neonatal Med 2013; 18:379-84. [PMID: 24035475 DOI: 10.1016/j.siny.2013.08.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Hypoxia-ischemia is an infrequent event which may occur prior to or during delivery, following a period of decreased placental and/or fetal blood flow. Following recovery, a reperfusion phase and secondary energy failure may occur 6-48 h subsequent to the initial insult. Therapeutic hypothermia may be offered to infants at risk for evolving encephalopathy if identified within the 6 h therapeutic window, and should be instituted as early as possible for eligible infants. Additionally, the clinician must pay close attention to supportive measures such as avoidance of hyperthermia, as well as comprehensive management of clinical or electrographic seizures, blood pressure, blood glucoses, and carbon dioxide levels.
Collapse
Affiliation(s)
- Ericalyn Kasdorf
- Department of Pediatrics, Division of Newborn Medicine, Weill Cornell Medical College, New York - Presbyterian Hospital, 525 East 68th Street, N-506, New York, NY 10065, USA.
| | | |
Collapse
|
19
|
van Kaam AH, De Jaegere AP, Rimensberger PC. Incidence of hypo- and hyper-capnia in a cross-sectional European cohort of ventilated newborn infants. Arch Dis Child Fetal Neonatal Ed 2013; 98:F323-6. [PMID: 23241364 DOI: 10.1136/archdischild-2012-302649] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To determine the incidence of hypo- and hyper-capnia in a European cohort of ventilated newborn infants. DESIGN AND SETTING Two-point cross-sectional prospective study in 173 European neonatal intensive care units. PATIENTS AND METHODS Patient characteristics, ventilator settings and measurements, and blood gas analyses were collected for endotracheally ventilated newborn infants on two separate dates. RESULTS A total of 1569 blood gas analyses were performed in 508 included patients with a mean±SD Pco2 of 48±12 mm Hg or 6.4±1.6 kPa (range 17-104 mm Hg or 2.3-13.9 kPa). Hypocapnia (Pco2<30 mm Hg or 4 kPa) and hypercapnia (Pco2>52 mm Hg or 7 kPa) was present in, respectively, 69 (4%) and 492 (31%) of the blood gases. Hypocapnia was most common in the first 3 days of life (7.3%) and hypercapnia after the first week of life (42.6%). Pco2 was significantly higher in preterm infants (49 mm Hg or 6.5 kPa) than term infants (43 mm Hg or 5.7 kPa) and significantly lower during pressure-limited ventilation (47 mm Hg or 6.3±1.6 kPa) compared with volume-targeted ventilation (51 mm Hg or 6.8±1.7 kPa) and high-frequency ventilation (50 mm Hg or 6.7±1.7 kPa). CONCLUSIONS This study shows that hypocapnia is a relatively uncommon finding during neonatal ventilation. The higher incidence of hypercapnia may suggest that permissive hypercapnia has found its way into daily clinical practice.
Collapse
Affiliation(s)
- Anton H van Kaam
- Department of Neonatology, Emma Children's Hospital AMC, Amsterdam, The Netherlands.
| | | | | | | |
Collapse
|
20
|
Trevisanuto D, Giuliotto S, Cavallin F, Doglioni N, Toniazzo S, Zanardo V. End-tidal carbon dioxide monitoring in very low birth weight infants: correlation and agreement with arterial carbon dioxide. Pediatr Pulmonol 2012; 47:367-72. [PMID: 22102598 DOI: 10.1002/ppul.21558] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 09/08/2011] [Indexed: 11/10/2022]
Abstract
OBJECTIVE We aimed to determine the correlation and the agreement between end-tidal carbon dioxide (ETCO(2)) and partial pressure of arterial carbon dioxide (PaCO(2) ) in very low birth weight infants (VLBWI); furthermore, we assessed factors that could affect the ETCO(2)-PaCO(2) relationship. METHODS Simultaneous end-tidal and arterial CO(2) pairs were obtained from ventilated VLBWI who were monitored by mainstream capnography and had umbilical arterial catheter. Correlation and agreement between ETCO(2) and PaCO(2) were evaluated by using Spearman test and Bland-Altman method, respectively. RESULTS A total of 143 simultaneous ETCO(2)-PaCO(2) pairs were analyzed from 45 ventilated VLBWI. There was a significant correlation (r = 0.69; P < 0.0001) between ETCO(2) and PaCO(2) values. The ETCO(2) value was lower than the corresponding PaCO(2) value in 94% pairs, with a mean bias of 13.5 ± 8.4 mmHg (95% agreement levels, -3.0 to 29.9 mmHg). Mean PaCO(2)-ETCO(2) bias was similar between ELBWI (13.1 ± 7.7 mmHg; 95% agreement levels, -1.9 and 28.2 mmHg) and infants with birth weight 1,001-1,500 g (14.8 ± 9.7 mmHg; 95% agreement levels -4.3 and 33.8 mmHg). The bias between ETCO(2) and PaCO(2) was significantly increased with increasing FiO(2), mean airway pressure and oxygenation index. Within each patient, there was a positive correlation (r = 0.78, P < 0.0001) between the changes in PaCO(2) and the simultaneous changes in ETCO(2). CONCLUSIONS In ventilated VLBWI, the correlation between mainstream ETCO(2) and PaCO(2) is good, but the agreement is poor and negatively influenced by the severity of pulmonary disease. Capnography is feasible in ELBWI. ETCO(2) should not replace PaCO(2) measurements in ventilated VLBWI, but may have a role to detect trends of PaCO(2).
Collapse
Affiliation(s)
- Daniele Trevisanuto
- Pediatric Department, Medical School, University of Padua, Azienda Ospedaliera Padova, Padua, Italy.
| | | | | | | | | | | |
Collapse
|
21
|
Subramanian S, El-Mohandes A, Dhanireddy R, Koch MA. Association of bronchopulmonary dysplasia and hypercarbia in ventilated infants with birth weights of 500-1,499 g. Matern Child Health J 2011; 15 Suppl 1:S17-26. [PMID: 21863239 PMCID: PMC3397775 DOI: 10.1007/s10995-011-0863-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Bronchopulmonary dysplasia (BPD) continues to be a major pulmonary complication in very low birth weight (VLBW) and extremely low birth weight (ELBW) survivors of neonatal intensive care units (NICUs). Many factors including partial pressures of carbon dioxide (PaCO: (2)) have been implicated as possible causes. Permissive hypercapnia has become a more common practice in ventilated infants, but its effect on BPD is unclear. The hypothesis of this study was that hypercarbia is associated with increased BPD in infants with birth weights of 500-1,499 g. Nine hospitals were involved in this observational cohort study. Maternal and infant information including socio-demographics, antenatal steroids, gender, race, gestational age, birth weight, intubation and ventilator status, physiologic variables and data on therapies were collected by chart abstraction. SNAP scores were assigned. Candidate BPD risk factors, including cumulative exposures derived from blood gas and ventilation data in the first 6 days of life, were identified. Risk models were developed for 425 preterm infants who survived to 36 weeks post-menstrual age. BPD occurrence was associated with the cumulative burden of MAP >0 cm H(2)O in the first 6 days of life (P < 0.0001). After adjustment for the burden of MAP, the occurrence of hypercarbia (PaCO: (2) >50 torr) was associated with a greater incidence of BPD (P = 0.024). Among 293 intubated, mechanically ventilated infants, those with hypercarbia occurring only when MAP ≤ 8 cm H(2)O, a scenario more comparable to permissive hypercapnia, also had increased BPD incidence compared to infants without hypercarbia (P = 0.0003). Hypercarbia during the first 6 days of life was associated with increased incidence of BPD in these infants. Mechanically ventilated infants with hypercarbia during low MAP also had a significant increase in BPD. Permissive hypercapnia in ventilated infants needs further close review before the practice becomes even more widespread.
Collapse
Affiliation(s)
- Siva Subramanian
- Neonatal Perinatal Medicine, Department of Pediatrics, Georgetown University Hospital, 3800 Reservoir Rd, NW, #M3400, Washington, DC 20007, USA
| | - Ayman El-Mohandes
- College of Public Health, University of Nebraska Medical Center, WH 5030, Omaha, NE 68198, USA
| | - Ramasubbareddy Dhanireddy
- Department of Pediatrics, Division of Neonatology, University of Tennessee Health Science Center, 853 Jefferson Avenue, Suite 201, Memphis, TN 38163, USA
| | - Matthew A. Koch
- Statistics and Epidemiology Division, RTI International, 3040 Cornwallis Road, Cox 305, P.O. Box 12194, Research Triangle Park, NC 27709-2194, USA
| |
Collapse
|
22
|
Wong DM, Alcott CJ, Wang C, Bornkamp JL, Young JL, Sponseller BA. Agreement between arterial partial pressure of carbon dioxide and saturation of hemoglobin with oxygen values obtained by direct arterial blood measurements versus noninvasive methods in conscious healthy and ill foals. J Am Vet Med Assoc 2011; 239:1341-7. [DOI: 10.2460/javma.239.10.1341] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
23
|
Caron Salloum A, Rakza T, Diependaele JF, Depoortere MH, Delepoulle F, Storme L. [Risk of accumulation of CO₂ in the oxygen chamber in "HOOD" (Experimental study on test bed)]. ANNALES FRANCAISES D'ANESTHESIE ET DE REANIMATION 2011; 30:718-721. [PMID: 21816562 DOI: 10.1016/j.annfar.2011.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Accepted: 04/11/2011] [Indexed: 05/31/2023]
Abstract
OBJECTIVES Oxygen hood is largely used to deliver O₂ to newborn infants with respiratory failure in the northern region of France. The oxygen flow is set to obtain the target arterial blood oxygen saturation. Thus, O₂ flow delivers into the hood may be below the recommended gas flow of 6L/min. However, gas flow below 6L/min exposes to CO₂ rebreathing. The aim of this study was to evaluate the effect of various rates of gas flows on the values of partial pressure of CO₂ into the hood. MATERIAL AND METHODS We measured CO₂ and O₂ partial pressure into hoods of two different volumes (4 and 10L) under two experimental bench test conditions. Protocol 1: gas flow was constant at 6L/min, while oxygen fraction varied from 0.21 to 1. Partial pressure of CO₂ and O₂ were recorded. Protocol 2: while O₂ fraction was kept constant, oxygen flow varied from 0.5 to 7L/min (by step of 0.5L/min). Partial pressure of CO₂ and O₂ were recorded. RESULTS Partial pressure of CO₂ increases proportionally to the decrease in the gas flow delivered into the hood, and reached 14 mmHg at gas flow of 0.5L/min. CONCLUSION Risk of CO₂ rebreathing exists as soon as the gas is delivered into the hood at minimal flow rates below 6L/min.
Collapse
Affiliation(s)
- A Caron Salloum
- Service de Néonatologie, CH de Dunkerque, 130, avenue Louis-Herbeaux, 59385 Dunkerque cedex 1, France
| | | | | | | | | | | |
Collapse
|
24
|
Booth EA, Dukatz C, Sood BG, Wider M. Near-infrared spectroscopy monitoring of cerebral oxygen during assisted ventilation. Surg Neurol Int 2011; 2:65. [PMID: 21697979 PMCID: PMC3115161 DOI: 10.4103/2152-7806.81722] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 04/04/2011] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Changes in the arterial partial pressure of CO(2) (PaCO(2)) has a direct though transient effect on the cerebral vasculature and cerebral circulation. Decreased PaCO(2) levels lead to vasoconstriction and can result in dangerously low levels of cerebral perfusion that resolve in 4-6 h. It is currently believed that perfusion abnormalities contribute to intraventricular hemorrhage (IVH) and periventricular leukomalacia (PVL) in the neonate. PaCO(2)-induced vasoconstriction may contribute to the pathology of IVH and PVL. METHODS Near-infrared spectroscopy [NIRS; (INVOS cerebral/somatic oximeter; Somanetics Corporation, Troy, MI, USA)] was utilized to determine changes in regional oxygenation (rSO(2)) of the brain in response to changes in ventilation in isoflurane anesthetized newborn piglets. RESULTS Changes in cerebral rSO(2) correlated significantly with end-tidal CO(2) levels and to blood flow in the common carotid artery. This correlation was significant during baseline conditions, after periods of CO(2) loading and during periods of hypothermia. CONCLUSIONS The results of the study demonstrate the utility of NIRS to accurately reflect changes in cerebral oxygenation and flow to the brain in response to changes in CO(2) levels in anesthetized, ventilated neonatal piglets. The use of NIRS may provide an early alert of low levels of cerebral blood flow and brain oxygenation, potentially helping in preventing the progression of IVH or PVL in the neonate.
Collapse
Affiliation(s)
- Erin A Booth
- Department of Medical Science, Somanetics Corporation, Troy, MI, USA
| | | | | | | |
Collapse
|
25
|
Takada S, Sampaio C, Allemandi W, Ito P, Takase L, Nogueira M. A modified rat model of neonatal anoxia: Development and evaluation by pulseoximetry, arterial gasometry and Fos immunoreactivity. J Neurosci Methods 2011; 198:62-9. [DOI: 10.1016/j.jneumeth.2011.03.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 03/08/2011] [Accepted: 03/09/2011] [Indexed: 11/30/2022]
|
26
|
Helmy MM, Tolner EA, Vanhatalo S, Voipio J, Kaila K. Brain alkalosis causes birth asphyxia seizures, suggesting therapeutic strategy. Ann Neurol 2011; 69:493-500. [PMID: 21337602 DOI: 10.1002/ana.22223] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 07/12/2010] [Accepted: 08/06/2010] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The mechanisms whereby birth asphyxia leads to generation of seizures remain unidentified. To study the possible role of brain pH changes, we used a rodent model that mimics the alterations in systemic CO(2) and O(2) levels during and after intrapartum birth asphyxia. METHODS Neonatal rat pups were exposed for 1 hour to hypercapnia (20% CO(2) in the inhaled gas), hypoxia (9% O(2)), or both (asphyxic conditions). CO(2) levels of 10% and 5% were used for graded restoration of normocapnia. Seizures were characterized behaviorally and utilizing intracranial electroencephalography. Brain pH and oxygen were measured with intracortical microelectrodes, and blood pH, ionized calcium, carbon dioxide, oxygen, and lactate with a clinical device. The impact of the postexposure changes in brain pH on seizure burden was assessed during 2 hours after restoration of normoxia and normocapnia. N-methyl-isobutyl-amiloride, an inhibitor of Na(+) /H(+) exchange, was given intraperitoneally. RESULTS Whereas hypercapnia or hypoxia alone did not result in an appreciable postexposure seizure burden, recovery from asphyxic conditions was followed by a large seizure burden that was tightly paralleled by a rise in brain pH, but no change in brain oxygenation. By graded restoration of normocapnia after asphyxia, the alkaline shift in brain pH and the seizure burden were strongly suppressed. The seizures were virtually blocked by preapplication of N-methyl-isobutyl-amiloride. INTERPRETATION Our data indicate that brain alkalosis after recovery from birth asphyxia plays a key role in the triggering of seizures. We question the current practice of rapid restoration of normocapnia in the immediate postasphyxic period, and suggest a novel therapeutic strategy based on graded restoration of normocapnia.
Collapse
|
27
|
Abstract
The first hour of a newborn's life is fraught with difficulty. Recommendations regarding the fundamental issues of resuscitation of these infants are developed and disseminated by the International Liaison Committee on Resuscitation and other organizations. However, these recommendations frequently do not address the needs of the very low birth weight infant and do not address some of the nuances that might lead to improved outcome. Improved organization and teamwork as well as improved monitoring and respiratory support can potentially improve the outcome of these infants.
Collapse
Affiliation(s)
- Roger F Soll
- Division of Neonatal Perinatal Medicine, Department of Pediatrics, College of Medicine, University of Vermont, Burlington, VT 05401, USA.
| | | |
Collapse
|
28
|
Thome UH, Ambalavanan N. Permissive hypercapnia to decrease lung injury in ventilated preterm neonates. Semin Fetal Neonatal Med 2009; 14:21-7. [PMID: 18974027 DOI: 10.1016/j.siny.2008.08.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Lung injury in ventilated premature infants occurs primarily through the mechanism of volutrauma, often due to the combination of high tidal volumes in association with a high end-inspiratory volume and occasionally end-expiratory alveolar collapse. Tolerating a higher level of arterial partial pressure of carbon dioxide (PaCO2) is considered as 'permissive hypercapnia' and when combined with the use of low tidal volumes may reduce volutrauma and lead to improved pulmonary outcomes. Permissive hypercapnia may also protect against hypocapnia-induced brain hypoperfusion and subsequent periventricular leukomalacia. However, extreme hypercapnia may be associated with an increased risk of intracranial hemorrhage. It may therefore be important to avoid large fluctuations in PaCO2 values. Recent randomized clinical trials in preterm infants have demonstrated that mild permissive hypercapnia is safe, but clinical benefits are modest. The optimal PaCO2 goal in clinical practice has not been determined, and the available evidence does not currently support a general recommendation for permissive hypercapnia in preterm infants.
Collapse
Affiliation(s)
- Ulrich H Thome
- Division of Neonatology, University Hospital for Children and Adolescents, 04103 Leipzig, Germany.
| | | |
Collapse
|
29
|
Abstract
In this article we have attempted to review the current pharmacological treatment options for infants with meconium aspiration syndrome with or without persistent pulmonary hypertension. These treatments include ventilatory support, surfactant treatment and inhaled nitric oxide (INO), in addition to older and newer pharmacological treatments. These include sedatives, muscle relaxants, alkali infusion, antibiotics and the newer vasodilators. Many aspects of treatment, including ventilatory care, surfactant treatment and the use of INO, are reviewed in great detail in this issue. On the other hand, many newer pharmacological modalities of treatment described here have not been evaluated with randomized control trials. We have given an overview of these emerging therapies.
Collapse
Affiliation(s)
- A Asad
- Division of Neonatology, Department of Pediatrics, University of Illinois at Medical Center, Chicago, IL 60612, USA
| | | |
Collapse
|
30
|
Abstract
UNLABELLED 'Permissive hypercapnia' is a familiar term in neonatal intensive care, given the widespread adoption of low-tidal-volume ventilation strategies applied with the goal of decreasing respiratory morbidity. Recent evidence suggesting that hypercapnic acidosis may itself have protective effects on the lung and other organs has led to the coining of a new phrase, 'therapeutic hypercapnia', which also encompasses the use of supplemental inspired CO(2). CONCLUSION Experimental evidence suggests that mild-moderate hypercapnia can improve tissue oxygenation and perfusion, which may ameliorate injury to the immature lung and brain. However, hypercapnia may also be associated with adverse outcomes, and the range of PaCO(2) levels that are both safe and effective for specific subsets of neonates has yet to be determined.
Collapse
Affiliation(s)
- Robert P Jankov
- Department of Paediatric, University of Toronto, Toronto, Ontario Canada.
| | | |
Collapse
|
31
|
Abstract
BACKGROUND The arterial partial pressure of carbon dioxide (PaCO2) represents the balance between CO2 production and consumption. Abnormal increase or decrease in PaCO2 can affect the body's internal environment and function. Permissive hypercapnia has aroused more attention as a novel ventilatory therapy. The aim of this study was to elucidate the effects of hypercapnia and hypocapnia on the functions of such neonatal organs as the lung and brain. DATA SOURCES The PubMed database was searched with the keywords "hypocapnia", "hypercapnia" and "newborn". RESULTS Hypocapnia is a risk factor for potential damage to the central nervous system, such as periventricular leukomalacia, intraventricular hemorrhage, cerebral palsy, cognition developmental disorder, and auditory deficit. Hyperventilation can lessen pulmonary artery hypertension to certain extent, but hypocapnia can aggravate ischemia/reperfusion-induced acute lung injury. Severe hypercapnia can induce intracranial hemorrhage, even consciousness alterations, cataphora, and hyperspasmia. Permissive hypercapnia can improve lung injury caused by diseases of the respiratory system, lessen mechanical ventilation-associated lung injury, reduce the incidence of bronchopulmonary dysplasia and protect against ventilation-induced brain injury. In addition, permissive hypercapnia plays a role in expanding cerebral vessels and increasing cerebral blood flow. CONCLUSIONS Severe hypercapnia and hypocapnia can cause neonatal brain injury and lung injury. Permissive hypercapnia can increase the survival of neonates with brain injury or respiratory system disease, and lessen the brain injury and lung injury caused by mechanical ventilation. However, the mechanism of permissive hypercapnia needs further exploration to confirm its safety and therapeutic utility.
Collapse
Affiliation(s)
- Wei Zhou
- Department of Neonatology, Guangzhou Children's Hospital, Guangzhou Medical College, Guangzhou 510120, China.
| | | |
Collapse
|
32
|
Eugênio GDR, Georgetti FCD. Uso de milrinona no tratamento da hipertensão pulmonar persistente do recém-nascido. REVISTA PAULISTA DE PEDIATRIA 2007. [DOI: 10.1590/s0103-05822007000400012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJETIVO: Descrever uma série de casos de recém-nascidos com hipertensão pulmonar persistente grave, que receberam milrinona para promover a vasodilatação pulmonar. MÉTODOS: Análise retrospectiva de prontuários de 28 pacientes com diagnóstico de hipertensão pulmonar persistente do recém-nascido (HPPRN). Após o diagnóstico, todos os pacientes receberam uma dose de ataque de 50mcg/kg de milrinona, seguida por 0,75mcg/kg/min. O índice de oxigenação (IO) foi calculado no início da infusão e 72 horas após o início da medicação. RESULTADOS: Todos os neonatos receberam milrinona e o sildenafil foi associado em 54%. O uso de dopamina assegurou a manutenção da pressão arterial em nível adequado em todos os casos. Sedação contínua, alcalinização e surfactante foram medidas coadjuvantes no tratamento. Durante a internação, sete pacientes (25%) evoluíram a óbito e todos eles apresentaram aumento do IO, com elevação da média de 25 para 38 com a milrinona. Os sobreviventes, com exceção de um neonato, apresentaram redução do IO em uso de milrinona, com queda da média de 19 para 7. CONCLUSÕES: O uso da milrinona parece ser uma alternativa para o tratamento da HPPRN, na ausência do óxido nítrico. A redução do IO com a medicação foi fator determinante da boa evolução dos pacientes. O índice de falha no tratamento com a milrinona nesta casuística foi semelhante ao encontrado na literatura para o uso de óxido nítrico.
Collapse
|
33
|
Fabres J, Carlo WA, Phillips V, Howard G, Ambalavanan N. Both extremes of arterial carbon dioxide pressure and the magnitude of fluctuations in arterial carbon dioxide pressure are associated with severe intraventricular hemorrhage in preterm infants. Pediatrics 2007; 119:299-305. [PMID: 17272619 DOI: 10.1542/peds.2006-2434] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE The goal was to test the hypothesis that extremes of PaCO2 during the first 4 days after birth are associated with severe intraventricular hemorrhage (grades 3 and 4). METHODS A single-center retrospective review of clinical and blood gas data in the first 4 postnatal days for 849 infants with birth weights of 401 to 1250 g was performed. The univariate and multivariate relationships of severe intraventricular hemorrhage with maximal and minimal PaCO2, PaCO2 averaged over time (time-weighted PaCO2), and measures of PaCO2 fluctuation (SD of PaCO2 and difference in PaCO2 [maximum minus minimum]) were assessed. RESULTS Birth weight (mean +/- SD) was 848 +/- 212 g, and the median gestational age was 26 weeks. Infants with severe intraventricular hemorrhage had higher maximal PaCO2 (median: 72 vs 59 mm Hg) and time-weighted PaCO2 (mean: 49 vs 47 mm Hg) values but lower minimal PaCO2 values (32 vs 37 mm Hg). High PaCO2, low PaCO2, SD of PaCO2, and difference in PaCO2 predicted severe intraventricular hemorrhage, but time-weighted average PaCO2 was not as predictive. CONCLUSIONS Both extremes and fluctuations of PaCO2 are associated with severe intraventricular hemorrhage. It may be prudent to avoid extreme hypocapnia and hypercapnia during the period of risk for intraventricular hemorrhage.
Collapse
Affiliation(s)
- Jorge Fabres
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | | | | |
Collapse
|
34
|
Ostrea EM, Villanueva-Uy ET, Natarajan G, Uy HG. Persistent pulmonary hypertension of the newborn: pathogenesis, etiology, and management. Paediatr Drugs 2007; 8:179-88. [PMID: 16774297 DOI: 10.2165/00148581-200608030-00004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Persistent pulmonary hypertension of the newborn (PPHN) is characterized by severe hypoxemia shortly after birth, absence of cyanotic congenital heart disease, marked pulmonary hypertension, and vasoreactivity with extrapulmonary right-to-left shunting of blood across the ductus arteriosus and/or foramen ovale. In utero, a number of factors determine the normally high vascular resistance in the fetal pulmonary circulation, which results in a higher pulmonary compared with systemic vascular pressure. However, abnormal conditions may arise antenatally, during, or soon after birth resulting in the failure of the pulmonary vascular resistance to normally decrease as the circulation evolves from a fetal to a postnatal state. This results in cyanosis due to right-to-left shunting of blood across normally existing cardiovascular channels (foramen ovale or ductus arteriosus) secondary to high pulmonary versus systemic pressure. The diagnosis is made by characteristic lability in oxygenation of the infant, echocardiographic evidence of increased pulmonary pressure, with demonstrable shunts across the ductus arteriosus or foramen ovale, and the absence of cyanotic heart disease lesions. Management of the disease includes treatment of underlying causes, sedation and analgesia, maintenance of adequate systemic blood pressure, and ventilator and pharmacologic measures to increase pulmonary vasodilatation, decrease pulmonary vascular resistance, increase blood and tissue oxygenation, and normalize blood pH. Inhaled nitric oxide has been one of the latest measures to successfully treat PPHN and significantly reduce the need for extracorporeal membrane oxygenation.
Collapse
|
35
|
Hosono S, Ohno T, Kimoto H, Shimizu M, Takahashi S, Harada K. Inhaled nitric oxide therapy might reduce the need for hyperventilation therapy in infants with persistent pulmonary hypertension of the newborn. J Perinat Med 2007; 34:333-7. [PMID: 16856826 DOI: 10.1515/jpm.2006.064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AIM To determine whether inhaled nitric oxide might reduce the need for excessive respiratory alkalosis to maintain systemic oxygenation in infants with persistent pulmonary hypertension of the newborn (PPHN). MATERIALS AND METHODS A retrospective historical cohort study of 34 infants with PPHN with oxygenation index (OI) of 25 or more, including 19 infants without inhaled nitric oxide (i-NO) therapy (control group) and 15 infants with inhaled nitric oxide therapy (i-NO group) was performed. The initial dose of 10 ppm of i-NO was administered and no responders received the maximum dose of 25 ppm. We evaluated the mortality rate and the change of OI index and PaCO(2) during the first 6 days. RESULTS There were no significant differences in characteristics between groups. Two of 15 in the i-NO group and 6 of 19 infants in the control group died during the first 48 h. Baseline OI, PaCO(2) and arterial pH were similar in the two groups. OI in the i-NO group was significantly higher than in the control group between 12 and 96 h. PaCO(2) in the i-NO group was higher than in the control group between 24 and 144 h. CONCLUSION i-NO therapy for PPHN might improve systemic oxygenation without excessive hypocapnia. However there was no reduction in duration of ventilation support or oxygen supply.
Collapse
Affiliation(s)
- Shigeharu Hosono
- Nihon University School of Medicine, Itabashi Hospital, Tokyo, Japan and Saitama Children's Medical Center, Saitama, Japan.
| | | | | | | | | | | |
Collapse
|
36
|
Abstract
Bronchopulmonary dysplasia (BPD) leads to considerable mortality and morbidity in premature infants. Although mechanical ventilation is lifesaving in infants with respiratory distress syndrome (RDS), it may contribute to lung injury and subsequently to BPD. Appropriate ventilatory strategies for reducing BPD include redefining the goals for "adequate gas exchange," using less mechanical ventilation support, refining the methods of mechanical ventilation, and using alternative techniques. Permissive hypercapnia, permissive hypoxemia, minimal peak pressures, rapid rates, early therapeutic continuous positive airway pressure (CPAP), and rapid extubation may help reduce mechanical ventilation-induced lung injury and possibly reduce BPD. Newer techniques of ventilation such as volume-targeted ventilation are also promising. High frequency ventilation has not been proven to reduce BPD. There is a lack of evidence-based guidelines on management of infants with established BPD. Optimization of clinical care practices and ancillary therapies need to be combined with ventilatory strategies to prevent and manage BPD.
Collapse
|
37
|
Probyn ME, Hooper SB, Dargaville PA, McCallion N, Harding R, Morley CJ. Effects of tidal volume and positive end-expiratory pressure during resuscitation of very premature lambs. Acta Paediatr 2005; 94:1764-70. [PMID: 16421037 DOI: 10.1111/j.1651-2227.2005.tb01851.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Guidelines recommend neonatal resuscitation without controlling tidal volume or positive end-expiratory pressure (PEEP). However, these may improve gas exchange, lung volume and outcome. AIM To investigate resuscitation of very premature lambs with a Laerdal bag without PEEP versus volume guarantee ventilation with PEEP. METHODS Anaesthetized lambs (n=20) delivered at 125 d gestation were randomized to three groups receiving 15 min resuscitation: (1) Laerdal bag and no PEEP; (2) ventilation with a tidal volume of 5 ml/kg and 8 cm H(2)O PEEP; (3) ventilation with 10 ml/kg and 8 cm H(2)O PEEP. They were then all ventilated for 2 h with tidal volumes of 5 or 10 ml/kg, and 8 cm H(2)O PEEP. Ventilation parameters and blood gases were recorded. RESULTS Different tidal volumes affected PaCO(2) within minutes, with 10 ml/kg causing severe hypocarbia. PEEP had little effect on PaCO(2). Oxygenation improved significantly with PEEP of 8 cm H(2)O, irrespective of tidal volume. CONCLUSION Very premature lambs can be resuscitated effectively using volume-guarantee ventilation and PEEP. Tidal volumes affected PaCO(2) within minutes but had little effect on oxygenation. PEEP halved the oxygen requirement compared with no PEEP. Resuscitating premature babies with controlled tidal volumes and PEEP might improve their outcome.
Collapse
Affiliation(s)
- Megan E Probyn
- Department of Physiology, Monash University, Melbourne, VIC 3800, Australia
| | | | | | | | | | | |
Collapse
|
38
|
KAISER JEFFREYR, GAUSS CHEATH, WILLIAMS DKEITH. The effects of hypercapnia on cerebral autoregulation in ventilated very low birth weight infants. Pediatr Res 2005; 58:931-5. [PMID: 16257928 PMCID: PMC1592234 DOI: 10.1203/01.pdr.0000182180.80645.0c] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Permissive hypercapnia, a strategy allowing high Pa(CO2), is widely used by neonatologists to minimize lung damage in ventilated very low birth weight (VLBW) infants. While hypercapnia increases cerebral blood flow (CBF), its effects on cerebral autoregulation of VLBW infants are unknown. Monitoring of mean CBF velocity (mCBFv), Pa(CO2), and mean arterial blood pressure (MABP) from 43 ventilated VLBW infants during the first week of life was performed during and after 117 tracheal suctioning procedures. Autoregulation status was determined during tracheal suctioning because it perturbs cerebral and systemic hemodynamics. The slope of the relationship between mCBFv and MABP was estimated when Pa(CO2) was fixed at 30, 35, 40, 45, 50, 55, and 60 mm Hg. A slope near or equal to 0 suggests intact autoregulation, i.e. CBF is not influenced by MABP. Increasing values >0 indicate progressively impaired autoregulation. Infants weighed 905 +/- 259 g and were 26.9 +/- 2.3 wk gestation. The autoregulatory slope increased as Pa(CO2)) increased from 30 to 60 mm Hg. While the slopes for Pa(CO2) values of 30 to 40 mm Hg were not statistically different from 0, slopes for Pa(CO2) > or = 45 mm Hg indicated a progressive loss of cerebral autoregulation. The autoregulatory slope increases with increasing Pa(CO2), suggesting the cerebral circulation becomes progressively pressure passive with hypercapnia. These data raise concerns regarding the use of permissive hypercapnia in ventilated VLBW infants during the first week of life, as impaired autoregulation during this period may be associated with increased vulnerability to brain injury.
Collapse
Affiliation(s)
- JEFFREY R. KAISER
- Correspondence: Jeffrey R. Kaiser, M.D., Arkansas Children’s Hospital, 800 Marshall St., #512, Little Rock, AR 72202; e-mail:
| | | | | |
Collapse
|
39
|
Abstract
OBJECTIVES To review the arterial carbon dioxide tensions (PaCO(2)) in newborn infants ventilated using synchronized intermittent mandatory ventilation (SIMV) in volume guarantee mode (using the Dräger Babylog 8000+) with a unit policy targeting tidal volumes of approximately 4 mL/kg. METHODS Data on ventilator settings and arterial PaCO(2) levels were collected on all arterial blood gases (ABG; n = 288) from 50 neonates (<33 weeks gestational age) ventilated using the Dräger Babylog 8000+ ventilator (Dräger Medizintechnik GmbH, Lübeck, Germany) in SIMV plus volume guarantee mode. Data were analysed for all blood gases done on the entire cohort in the first 48 h of life and a subanalysis was done on the first gas for each infant (n = 38) ventilated using volume guarantee from admission to the nursery. The number of ABG showing severe hypocapnoea (PaCO(2) < 25 mmHg) and/or severe hypercapnoea (PaCO(2) > 65 mmHg) were determined. RESULTS The mean (SD) PaCO(2) during the first 48 h was 46.6 (9.0) mmHg. The mean (SD) PaCO(2) on the first blood gas of those infants commenced on volume guarantee from admission was 45.1 (12.5) mmHg. Severe hypo- or hypercapnoea occurred in 8% of infants at the time of their first blood gas measurement, and in <4% of blood gas measurements in the first 48 h. CONCLUSIONS Infants ventilated with volume guarantee ventilation targeting approximately 4 mL/kg (range: 2.9-5.1) have acceptable PaCO(2) levels at the first blood gas measurement and during the first 48 h of life; and avoid severe hypo- or hypercapnoea over 90% of the time.
Collapse
Affiliation(s)
- Catherine Dawson
- Grantley Stable Neonatal Unit, Royal Women's Hospital, University of Queensland, Brisbane, Queensland, Australia
| | | |
Collapse
|
40
|
Rüdiger M, Töpfer K, Hammer H, Schmalisch G, Wauer RR. A survey of transcutaneous blood gas monitoring among European neonatal intensive care units. BMC Pediatr 2005; 5:30. [PMID: 16092957 PMCID: PMC1192805 DOI: 10.1186/1471-2431-5-30] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2004] [Accepted: 08/10/2005] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND PCO2 and PO2 are important monitoring parameters in neonatal intensive care units (NICU). Compared to conventional blood gas measurements that cause significant blood loss in preterms, transcutaneous (tc) measurements allow continuous, non-invasive monitoring of blood gas levels. The aim of the study was to survey the usage and opinions among German speaking NICUs concerning tc blood gas monitoring. METHODS A questionnaire was developed and sent to 56 head nurses of different NICUs in Germany, Switzerland and Austria. RESULTS A completely answered questionnaire was obtained from 41 NICUs. In two of these units tc measurements are not performed. In most NICUs (77%), both PtcO2 and PtcCO2 are measured simultaneously. Most units change the sensors every 3 hours; however, the recommended temperature of 44 degrees C is used in only 15% of units. In only 8% of units are arterial blood gases obtained to validate tc values. Large variations were found concerning the targeted level of oxygen saturation [median upper limit: 95% (range 80-100%); median lower limit: 86% (range 75-93%)] and PO2 [median upper limit: 70 mmHg (range 45-90 mmHg); median lower limit: 44 mmHg (range 30-60 mmHg)]. CONCLUSION Our survey shows that the use of tc monitors remains widespread among German speaking NICUs, despite earlier data suggesting that their use had been abandoned in many NICUs worldwide. In addition, we suggest that the current method of monitoring oxygenation may not prevent hyperoxemia in preterm infants.
Collapse
Affiliation(s)
- Mario Rüdiger
- Clinic of Neonatology; Universitätsmedizin Berlin, Charité-Mitte; 10098 Berlin; Germany
- Department for Neonatology, Medical University Innsbruck, Department for Neonatology, 6020 Innsbruck, Austria
| | - Kerstin Töpfer
- Clinic of Neonatology; Universitätsmedizin Berlin, Charité-Mitte; 10098 Berlin; Germany
| | - Hannes Hammer
- Clinic of Neonatology; Universitätsmedizin Berlin, Charité-Mitte; 10098 Berlin; Germany
| | - Gerd Schmalisch
- Clinic of Neonatology; Universitätsmedizin Berlin, Charité-Mitte; 10098 Berlin; Germany
| | - Roland R Wauer
- Clinic of Neonatology; Universitätsmedizin Berlin, Charité-Mitte; 10098 Berlin; Germany
| |
Collapse
|
41
|
Abstract
Anaesthesiologists must be familiar with the particularities of the respiratory physiology of newborns and infants when providing perioperative care to these patients. Even brief periods of inadequate respiratory support can cause atelectatrauma and volutrauma which in turn can have deleterious cardiorespiratory consequences and accentuate pre-existing lung disease. A variety of respirators and respiratory support strategies are available and should be selected to meet a patient's particular needs. Optimal PEEP and normal tidal volumes during conventional ventilation, high volume strategy during high frequency ventilation, and permissive hypercapnia are the corner stones of a lung protective strategy. Using an interdisciplinary approach, surgery in the intensive care unit using total intravenous anaesthesia with the uninterrupted use of the ICU equipment is an attractive option for the most vulnerable patients in this age group.
Collapse
Affiliation(s)
- T M Berger
- Neonatologische und pädiatrische Intensivpflegestation, Kinderspital Luzern, Schweiz.
| | | |
Collapse
|
42
|
Donn SM, Sinha SK. Can mechanical ventilation strategies reduce chronic lung disease? ACTA ACUST UNITED AC 2004; 8:441-8. [PMID: 15001116 DOI: 10.1016/s1084-2756(03)00124-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2003] [Accepted: 07/01/2003] [Indexed: 10/27/2022]
Abstract
Chronic lung disease (CLD) continues to be a significant complication in newborn infants undergoing mechanical ventilation for respiratory failure. Although the aetiology of CLD is multifactorial, specific factors related to mechanical ventilation, including barotrauma, volutrauma and atelectrauma, have been implicated as important aetiologic mechanisms. This article discusses the ways in which these factors might be manipulated by various mechanical ventilatory strategies to reduce ventilator-induced lung injury. These include continuous positive airway pressure, permissive hypercapnia, patient-triggered ventilation, volume-targeted ventilation, proportional assist ventilation, high-frequency ventilation and real-time monitoring.
Collapse
Affiliation(s)
- Steven M Donn
- The Division of Neonatal-Perinatal Medicine, Department of Pediatrics, C.S. Mott Children's Hospital, University of Michigan Health System, Ann Arbor, MI, USA.
| | | |
Collapse
|
43
|
Rai S, Engelberts D, Laffey JG, Frevert C, Kajikawa O, Martin TR, Post M, Kavanagh BP. Therapeutic hypercapnia is not protective in the in vivo surfactant-depleted rabbit lung. Pediatr Res 2004; 55:42-9. [PMID: 14561781 DOI: 10.1203/01.pdr.0000098502.72182.55] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Permissive hypercapnia because of reduced tidal volume is associated with improved survival in lung injury, whereas therapeutic hypercapnia-deliberate elevation of arterial Pco2-protects against in vivo reperfusion injury and injury produced by severe lung stretch. No published studies to date have examined the effects of CO2 on in vivo models of neonatal lung injury. We used an established in vivo rabbit model of surfactant depletion to investigate whether therapeutic hypercapnia would improve oxygenation and protect against ventilator-induced lung injury. Animals were randomized to injurious (tidal volume, 12 mL/kg; positive end-expiratory pressure, 0 cm H2O) or protective ventilatory strategy (tidal volume, 5 mL/kg; positive end-expiratory pressure, 12.5 cm H2O), and to receive either control conditions or therapeutic hypercapnia (fraction of inspired CO2, 0.12). Oxygenation (alveolar-arterial O2 difference, arterial Po2), lung injury (alveolar-capillary protein leak, impairment of static compliance), and selected bronchoalveolar lavage and plasma cytokines (IL-8, growth-related oncogene, monocyte chemoattractant protein-1, and tumor necrosis factor-alpha) were measured. Injurious ventilation resulted in a large alveolar-arterial O2 gradient, elevated peak airway pressure, increased protein leak, and impaired lung compliance. Therapeutic hypercapnia did not affect any of these outcomes. Tumor necrosis factor-alpha was not increased by mechanical stretch in any of the groups. Therapeutic hypercapnia abolished the stretch-induced increase in bronchoalveolar lavage monocyte chemoattractant protein-1, but did not affect any of the other mediators studied. Therapeutic hypercapnia may attenuate the impairment in oxygenation and inhibit certain cytokines. Because hypercapnia inhibits certain cytokines but does not alter lung injury, the pathogenic role of these cytokines in lung injury is questionable.
Collapse
Affiliation(s)
- Sharadindu Rai
- The Lung Biology Program, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Nguyen AT, Aly H, Milner J, Patel KM, El-Mohandes A. Partial pressure of carbon dioxide in extremely low birth weight infants supported by nasal prongs continuous positive airway pressure. Pediatrics 2003; 112:e208-11. [PMID: 12949314 DOI: 10.1542/peds.112.3.e208] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Traditionally, delivery room management of extremely low birth weight (ELBW) infants consisted of immediate intubation and mechanical ventilation. There have been recent reports of success using nasal prongs continuous positive airway pressure (NCPAP) in this population. Data on the partial pressure of carbon dioxide (PCO(2)) in spontaneously breathing ELBW infants is very limited. The objective of this study was to determine the trend of the average PCO(2) in the spontaneously breathing ELBW infants, while on NCPAP, during the first week of life and to determine whether a brief period of mechanical ventilation affects the PCO(2) levels after extubation. METHODS This is a retrospective cohort study of infants who had birth weights <1000 g and were admitted to the neonatal intensive care unit at our institution. These ELBW infants were divided into groups on the basis of whether they were never intubated (group 1) or were intubated for <48 hours (group 2). Average daily PCO(2) levels while on NCPAP were compared between the 2 groups. Minimum and maximum PCO(2) levels were also compared with a third group of infants (group 3), who were intubated for >48 hours and treated mainly with mechanical ventilation during the first week of life. RESULTS Sixty-two ELBW infants were included in this study: 24 infants in group 1, 19 infants in group 2, and 19 infants in group 3. There was no significant difference between the average PCO(2) levels of group 1 and group 2 during the first week of life. The daily PCO(2) level during the first week of life for infants who were breathing spontaneously on NCPAP had a mean value of 39.73 +/- 1.78 mm Hg. There was no difference between the daily average minimum PCO(2) levels among the 3 groups. Group 3, however, had significantly higher maximum PCO(2) levels compared with the first 2 groups during days 2 through 7 of life. CONCLUSIONS Daily average PCO(2) levels in the spontaneously breathing ELBW infants during the first week of life remains at approximately 40 mm Hg. These levels seem to be unaffected by an initial brief period of mechanical ventilation. Infants who are treated with longer periods of mechanical ventilation have higher daily maximum PCO(2) levels during the first week of life. Additional studies are required to detect neurodevelopmental outcomes of these 3 groups.
Collapse
Affiliation(s)
- An T Nguyen
- Department of Pediatrics, Children's National Medical Center, Washington, DC, USA
| | | | | | | | | |
Collapse
|
45
|
Hassan IAA, Wickramasinghe YA, Spencer SA. Effect of a change in global metabolic rate on peripheral oxygen consumption in neonates. Arch Dis Child Fetal Neonatal Ed 2003; 88:F143-6. [PMID: 12598505 PMCID: PMC1721498 DOI: 10.1136/fn.88.2.f143] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM To evaluate the effect of an induced change in global metabolic rate on peripheral oxygen consumption (VO(2)) in healthy full term neonates. SUBJECTS AND METHODS Twenty four healthy full term neonates were studied. Peripheral VO(2) was measured by near infrared spectroscopy (NIRS) using arterial occlusion and measurement of the oxyhaemoglobin (HbO(2)) decrement slope. Global VO(2) was measured by open circuit calorimetry. Global and peripheral VO(2) were measured in each neonate before and after a routine bath. Abdominal and forearm skin temperatures were also recorded. RESULTS Nineteen neonates completed the study. Global VO(2) increased by 30.7% (p = 0.001), and peripheral VO(2) by 23.1% (p = 0.001). A correlation between the fractional changes in global and peripheral VO(2) was apparent (r = 0.76, p = 0.001). Abdominal skin temperature decreased by 0.8 degrees C (p = 0.001), and forearm skin temperature by 0.6 degrees C (p = 0.04). CONCLUSIONS Measurement of peripheral VO(2) using NIRS with arterial occlusion is responsive to conditions that increase global metabolic rate. Any change in global VO(2) must be taken into consideration during the interpretation of peripheral VO(2) measurements in neonates.
Collapse
Affiliation(s)
- I A-A Hassan
- Neonatal Unit, City General Hospital, Stoke on Trent, UK
| | | | | |
Collapse
|
46
|
Hassan IAA, Wickramasinghe YA, Spencer SA. Effect of limb cooling on peripheral and global oxygen consumption in neonates. Arch Dis Child Fetal Neonatal Ed 2003; 88:F139-42. [PMID: 12598504 PMCID: PMC1721525 DOI: 10.1136/fn.88.2.f139] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM To evaluate peripheral oxygen consumption (VO(2)) measurements using near infrared spectroscopy (NIRS) with arterial occlusion in healthy term neonates by studying the effect of limb cooling on peripheral and global VO(2). SUBJECTS AND METHODS Twenty two healthy term neonates were studied. Peripheral VO(2) was measured by NIRS using arterial occlusion and measurement of the oxyhaemoglobin (HbO(2)) decrement slope. Global VO(2) was measured by open circuit calorimetry. Global and peripheral VO(2) was measured in each neonate before and after limb cooling. RESULTS In 10 neonates, a fall in forearm temperature of 2.2 degrees C (mild cooling) decreased forearm VO(2) by 19.6% (p < 0.01). Global VO(2) did not change. In 12 neonates, a fall in forearm temperature of 4 degrees C (moderate cooling) decreased forearm VO(2) by 34.7% (p < 0.01). Global VO(2) increased by 17.6% (p < 0.05). CONCLUSIONS The NIRS arterial occlusion method is able to measure changes in peripheral VO(2) induced by limb cooling. The changes are more pronounced with moderate limb cooling when a concomitant rise in global VO(2) is observed. Change in peripheral temperature must be taken into consideration in the interpretation of peripheral VO(2) measurements in neonates.
Collapse
Affiliation(s)
- I A-A Hassan
- Neonatal Unit, City General Hospital, Stoke on Trent, UK
| | | | | |
Collapse
|
47
|
Abstract
Although lifesaving, mechanical ventilation can result in lung injury and contribute to the development of bronchopulmonary dysplasia. The most critical determinants of lung injury are tidal volume and end-inspiratory lung volume. Permissive hypercapnia offers to maintain gas exchange with lower tidal volumes and thus decrease lung injury. Further physiologic benefits include improved oxygen delivery and neuroprotection, the latter through both avoidance of accidental hypocapnia, which is associated with a poor neurologic outcome, and direct cellular effects. Clinical trials in adults with acute respiratory failure indicated improved survival and reduced incidence of organ failure in subjects managed with low tidal volumes and permissive hypercapnia. Retrospective studies in low birth weight infants found an association of bronchopulmonary dysplasia with low PaCO(2). Randomized clinical trials of low birth weight infants did not achieve sufficient statistical power to demonstrate a reduction of BPD by permissive hypercapnia, but strong trends indicated the possibility of important benefits without increased adverse events. Herein, we review the mechanisms leading to lung injury, the physiologic effects of hypercapnia, the dangers of hypocapnia, and the available clinical data.
Collapse
Affiliation(s)
- Ulrich H Thome
- Division of Neonatology and Pediatric Critical Care, Children's Hospital, University of Ulm, 89070 Ulm, Germany
| | | |
Collapse
|
48
|
Carlo WA, Stark AR, Wright LL, Tyson JE, Papile LA, Shankaran S, Donovan EF, Oh W, Bauer CR, Saha S, Poole WK, Stoll B. Minimal ventilation to prevent bronchopulmonary dysplasia in extremely-low-birth-weight infants. J Pediatr 2002; 141:370-4. [PMID: 12219057 DOI: 10.1067/mpd.2002.127507] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To determine whether minimal ventilation decreases death or bronchopulmonary dysplasia (BPD). STUDY DESIGN Infants with birth weight 501 g to 1000 g and mechanically ventilated before 12 hours were randomly assigned to minimal ventilation (partial pressure of carbon dioxide [PCO(2)] target >52 mm Hg) or routine ventilation (PCO(2) target <48 mm Hg) and a tapered dexamethasone course or saline placebo for 10 days, using a 2 x 2 factorial design. The primary outcome was death or BPD at 36 weeks' postmenstrual age. RESULTS After enrollment of 220 patients, the trial was halted because of unanticipated nonrespiratory adverse events related to dexamethasone therapy. The relative risk for death or BPD at 36 weeks in the minimal versus routine ventilation groups was 0.93 (95% CI, 0.77-1.12; P =.43). Ventilator support at 36 weeks was 1% in the minimal versus 16% in the routine group (P <.01). Major morbidities and long-term outcome were comparable in both treatment groups. CONCLUSIONS With the sample size studied, minimal ventilation did not reduce the incidence of death or BPD. The reduced ventilator support at 36 weeks in the minimal ventilation group warrants further study of this intervention.
Collapse
Affiliation(s)
- Waldemar A Carlo
- University of Alabama at Birmingham, Division of Neonatology, 35233, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|