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Deprez A, Poletto Bonetto JH, Ravizzoni Dartora D, Dodin P, Nuyt AM, Luu TM, Dumont NA. Impact of preterm birth on muscle mass and function: a systematic review and meta-analysis. Eur J Pediatr 2024; 183:1989-2002. [PMID: 38416257 DOI: 10.1007/s00431-023-05410-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 12/21/2023] [Accepted: 12/23/2023] [Indexed: 02/29/2024]
Abstract
Individuals born preterm present lower exercise capacity. Along with the cardiopulmonary responses and activity level, muscle strength is a key determinant of exercise capacity. This systematic review aimed to summarize the current knowledge on the impact of preterm birth on skeletal muscle mass and function across the lifespan. The databases PubMed, MEDLINE, EBM, Embase, CINAHL Plus, Global Index Medicus, and Google Scholar were searched using keywords and MeSH terms related to skeletal muscle, preterm birth, and low birth weight. Two independent reviewers undertook study selection, data extraction, and quality appraisal using Covidence review management. Data were pooled to estimate the prematurity effect on muscle mass and function using the R software. From 4378 studies retrieved, 132 were full-text reviewed and 25 met the inclusion/exclusion criteria. Five studies presented a low risk of bias, and 5 had a higher risk of bias due to a lack of adjustment for confounding factors and presenting incomplete outcomes. Meta-analyses of pooled data from homogenous studies indicated a significant reduction in muscle thickness and jump test (muscle power) in individuals born preterm versus full-term with standardized mean difference and confidence interval of - 0.58 (0.27, 0.89) and - 0.45 (0.21, 0.69), respectively. Conclusion: Overall, this systematic review summarizing the existing literature on the impact of preterm birth on skeletal muscle indicates emerging evidence that individuals born preterm, display alteration in the development of their skeletal muscle mass and function. This work also highlights a clear knowledge gap in understanding the effect of preterm birth on skeletal muscle development. What is Known: • Preterm birth, which occurs at a critical time of skeletal muscle development and maturation, impairs the development of different organs and tissues leading to a higher risk of comorbidities such as cardiovascular diseases. • Preterm birth is associated with reduced exercise capacity. What is New: • Individuals born preterm display alterations in muscle mass and function compared to individuals born at term from infancy to adulthood. • There is a need to develop preventive or curative interventions to improve skeletal muscle health in preterm-born individuals.
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Affiliation(s)
- Alyson Deprez
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, 3175 Chemin de La Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Jéssica H Poletto Bonetto
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, 3175 Chemin de La Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
| | - Daniela Ravizzoni Dartora
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, 3175 Chemin de La Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
| | - Philippe Dodin
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, 3175 Chemin de La Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
| | - Anne Monique Nuyt
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, 3175 Chemin de La Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
- Department of Pediatrics, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Thuy Mai Luu
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, 3175 Chemin de La Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
- Department of Pediatrics, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Nicolas A Dumont
- Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, 3175 Chemin de La Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada.
- School of Rehabilitation, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.
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Biazus GF, Kaminski DM, Silveira RDC, Procianoy RS. Incidence of nasal pressure injury in preterm infants on nasal mask noninvasive ventilation. REVISTA PAULISTA DE PEDIATRIA : ORGAO OFICIAL DA SOCIEDADE DE PEDIATRIA DE SAO PAULO 2023; 41:e2022093. [PMID: 36921179 PMCID: PMC10014020 DOI: 10.1590/1984-0462/2023/41/2022093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 11/07/2022] [Indexed: 03/18/2023]
Abstract
OBJECTIVE The aim of this study was to evaluate the incidence of nasal injury in preterm newborns (NB) using the Neonatal Skin Condition Score within 7 days of noninvasive ventilation (NIV) and to compare the incidence of injury in NB weighing ≥1,000 g and those weighing <1,000 g at the time of initiation of NIV support. METHODS This is a prospective, observational study carried out in a neonatal intensive care unit of a public hospital in Rio Grande do Sul from July 2016 to January 2021. Patients were stratified into two groups at the time of NIV initiation: group 1 (weight ≥1,000 g) and group 2 (weight <1,000 g). To assess the condition of nasal injury, a rating scale called the Neonatal Skin Condition Score was applied during the first seven consecutive days on NIV. Kaplan-Meier, log-rank test, and Cox proportional hazards regression were used to estimate the hazard ratio (HR) and 95% confidence interval (CI). RESULTS In total, 184 NB were evaluated. Nasal injury was reported in 55 (30%) NB. The risk of nasal injury was 74% higher in group 2 (19/45) than in group 1 (36/139) (HR: 1.74; 95%CI 0.99-3.03, p=0.048). CONCLUSION The incidence of nasal injury in infants submitted to NIV by nasal mask was high, and the risk of this injury was greater in preterm infants weighing <1,000 g.
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Affiliation(s)
| | | | - Rita de Cassia Silveira
- Hospital de Clínicas de Porto Alegre, RS, Brazil.,Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Renato Soibelmann Procianoy
- Hospital de Clínicas de Porto Alegre, RS, Brazil.,Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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3
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Dassios T, Vervenioti A, Dimitriou G. Respiratory muscle function in the newborn: a narrative review. Pediatr Res 2022; 91:795-803. [PMID: 33875805 PMCID: PMC8053897 DOI: 10.1038/s41390-021-01529-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/24/2021] [Accepted: 03/29/2021] [Indexed: 02/02/2023]
Abstract
Our aim was to summarise the current evidence and methods used to assess respiratory muscle function in the newborn, focusing on current and future potential clinical applications. The respiratory muscles undertake the work of breathing and consist mainly of the diaphragm, which in the newborn is prone to dysfunction due to lower muscle mass, flattened shape and decreased content of fatigue-resistant muscle fibres. Premature infants are prone to diaphragmatic dysfunction due to limited reserves and limited capacity to generate force and avoid fatigue. Methods to assess the respiratory muscles in the newborn include electromyography, maximal respiratory pressures, assessment for thoraco-abdominal asynchrony and composite indices, such as the pressure-time product and the tension time index. Recently, there has been significant interest and a growing body of research in assessing respiratory muscle function using bedside ultrasonography. Neurally adjusted ventilator assist is a novel ventilation mode, where the level of the respiratory support is determined by the diaphragmatic electrical activity. Prolonged mechanical ventilation, hypercapnia and hypoxia, congenital anomalies and systemic or respiratory infection can negatively impact respiratory muscle function in the newborn, while caffeine and synchronised or volume-targeted ventilation have a positive effect on respiratory muscle function compared to conventional, non-triggered or pressure-limited ventilation, respectively. IMPACT: Respiratory muscle function is impaired in prematurely born neonates and infants with congenital anomalies, such as congenital diaphragmatic hernia. Respiratory muscle function is negatively affected by prolonged ventilation and infection and positively affected by caffeine and synchronised compared to non-synchronised ventilation modes. Point-of-care diaphragmatic ultrasound and neurally adjusted ventilator assist are recent diagnostic and therapeutic technological developments with significant clinical applicability.
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Affiliation(s)
- Theodore Dassios
- Department of Women and Children's Health, King's College London, London, UK. .,Department of Paediatrics, University of Patras, Patras, Greece.
| | - Aggeliki Vervenioti
- grid.11047.330000 0004 0576 5395Department of Paediatrics, University of Patras, Patras, Greece
| | - Gabriel Dimitriou
- grid.11047.330000 0004 0576 5395Department of Paediatrics, University of Patras, Patras, Greece
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Crulli B, Kawaguchi A, Praud JP, Petrof BJ, Harrington K, Emeriaud G. Evolution of inspiratory muscle function in children during mechanical ventilation. Crit Care 2021; 25:229. [PMID: 34193216 PMCID: PMC8243304 DOI: 10.1186/s13054-021-03647-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 06/18/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND There is no universally accepted method to assess the pressure-generating capacity of inspiratory muscles in children on mechanical ventilation (MV), and no study describing its evolution over time in this population. METHODS In this prospective observational study, we have assessed the function of the inspiratory muscles in children on various modes of MV. During brief airway occlusion maneuvers, we simultaneously recorded airway pressure depression at the endotracheal tube (ΔPaw, force generation) and electrical activity of the diaphragm (EAdi, central respiratory drive) over five consecutive inspiratory efforts. The neuro-mechanical efficiency ratio (NME, ΔPaw/EAdimax) was also computed. The evolution over time of these indices in a group of children in the pediatric intensive care unit (PICU) was primarily described. As a secondary objective, we compared these values to those measured in a group of children in the operating room (OR). RESULTS In the PICU group, although median NMEoccl decreased over time during MV (regression coefficient - 0.016, p = 0.03), maximum ΔPawmax remained unchanged (regression coefficient 0.109, p = 0.50). Median NMEoccl at the first measurement in the PICU group (after 21 h of MV) was significantly lower than at the only measurement in the OR group (1.8 cmH2O/µV, Q1-Q3 1.3-2.4 vs. 3.7 cmH2O/µV, Q1-Q3 3.5-4.2; p = 0.015). Maximum ΔPawmax in the PICU group was, however, not significantly different from the OR group (35.1 cmH2O, Q1-Q3 21-58 vs. 31.3 cmH2O, Q1-Q3 28.5-35.5; p = 0.982). CONCLUSIONS The function of inspiratory muscles can be monitored at the bedside of children on MV using brief airway occlusions. Inspiratory muscle efficiency was significantly lower in critically ill children than in children undergoing elective surgery, and it decreased over time during MV in critically ill children. This suggests that both critical illness and MV may have an impact on inspiratory muscle efficiency.
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Affiliation(s)
- Benjamin Crulli
- Pediatric Intensive Care Unit, CHU Sainte-Justine, Université de Montréal, 3175 chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
| | - Atsushi Kawaguchi
- Pediatric Intensive Care Unit, CHU Sainte-Justine, Université de Montréal, 3175 chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
- Pediatric Intensive Care Unit, Children's Hospital of Eastern Ontario, University of Ottawa, 401 Smyth Road, Ottawa, ON, K1H 8L1, Canada
- Department of Intensive Care Medicine, Tokyo Women's Medical University, Tokyo, Japan
| | - Jean-Paul Praud
- Neonatal Respiratory Research Unit, Departments of Pediatrics and Pharmacology-Physiology, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, QC, J1H 5N4, Canada
| | - Basil J Petrof
- Meakins-Christie Laboratories and Translational Research in Respiratory Diseases Program, McGill University Health Centre and Research Institute, 1001 Boulevard Décarie, Montreal, QC, H4A 3J1, Canada
| | - Karen Harrington
- Pediatric Intensive Care Unit, CHU Sainte-Justine, Université de Montréal, 3175 chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada
| | - Guillaume Emeriaud
- Pediatric Intensive Care Unit, CHU Sainte-Justine, Université de Montréal, 3175 chemin de la Côte-Sainte-Catherine, Montreal, QC, H3T 1C5, Canada.
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Abstract
OBJECTIVES This review discusses the different techniques used at the bedside to assess respiratory muscle function in critically ill children and their clinical applications. DATA SOURCES A scoping review of the medical literature on respiratory muscle function assessment in critically ill children was conducted using the PubMed search engine. STUDY SELECTION We included all scientific, peer-reviewed studies about respiratory muscle function assessment in critically ill children, as well as some key adult studies. DATA EXTRACTION Data extracted included findings or comments about techniques used to assess respiratory muscle function. DATA SYNTHESIS Various promising physiologic techniques are available to assess respiratory muscle function at the bedside of critically ill children throughout the disease process. During the acute phase, this assessment allows a better understanding of the pathophysiological mechanisms of the disease and an optimization of the ventilatory support to increase its effectiveness and limit its potential complications. During the weaning process, these physiologic techniques may help predict extubation success and therefore optimize ventilator weaning. CONCLUSIONS Physiologic techniques are useful to precisely assess respiratory muscle function and to individualize and optimize the management of mechanical ventilation in children. Among all the available techniques, the measurements of esophageal pressure and electrical activity of the diaphragm appear particularly helpful in the era of individualized ventilatory management.
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Khemani RG, Hotz JC, Klein MJ, Kwok J, Park C, Lane C, Smith E, Kohler K, Suresh A, Bornstein D, Elkunovich M, Ross PA, Deakers T, Beltramo F, Nelson L, Shah S, Bhalla A, Curley MAQ, Newth CJL. A Phase II randomized controlled trial for lung and diaphragm protective ventilation (Real-time Effort Driven VENTilator management). Contemp Clin Trials 2019; 88:105893. [PMID: 31740425 DOI: 10.1016/j.cct.2019.105893] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 11/05/2019] [Accepted: 11/14/2019] [Indexed: 11/18/2022]
Abstract
Lung Protective Mechanical Ventilation (MV) of critically ill adults and children is lifesaving but it may decrease diaphragm contraction and promote Ventilator Induced Diaphragm Dysfunction (VIDD). An ideal MV strategy would balance lung and diaphragm protection. Building off a Phase I pilot study, we are conducting a Phase II controlled clinical trial that seeks to understand the evolution of VIDD in critically ill children and test whether a novel computer-based approach (Real-time Effort Driven ventilator management (REDvent)) can balance lung and diaphragm protective ventilation to reduce time on MV. REDvent systematically adjusts PEEP, FiO2, inspiratory pressure, tidal volume and rate, and uses real-time measures from esophageal manometry to target normal levels of patient effort of breathing. This trial targets 276 children with pulmonary parenchymal disease. Patients are randomized to REDvent vs. usual care for the acute phase of MV (intubation to first Spontaneous Breathing Trial (SBT)). Patients in either group who fail their first SBT will be randomized to REDvent vs usual care for weaning phase management (interval from first SBT to passing SBT). The primary clinical outcome is length of weaning, with several mechanistic outcomes. Upon completion, this study will provide important information on the pathogenesis and timing of VIDD during MV in children and whether this computerized protocol targeting lung and diaphragm protection can lead to improvement in intermediate clinical outcomes. This will form the basis for a larger, Phase III multi-center study, powered for key clinical outcomes such as 28-day ventilator free days. Clinical Trials Registration: NCT03266016.
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Affiliation(s)
- Robinder G Khemani
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America; University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America.
| | - Justin C Hotz
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America
| | - Margaret J Klein
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America
| | - Jeni Kwok
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America
| | - Caron Park
- University of Southern California, Keck School of Medicine, Department of Preventative Medicine, United States of America
| | - Christianne Lane
- University of Southern California, Keck School of Medicine, Department of Preventative Medicine, United States of America
| | - Erin Smith
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America
| | - Kristen Kohler
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America
| | - Anil Suresh
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America
| | - Dinnel Bornstein
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America
| | - Marsha Elkunovich
- University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America; Children's Hospital of Los Angeles, Department of Emergency Medicine, United States of America
| | - Patrick A Ross
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America; University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America
| | - Timothy Deakers
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America; University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America
| | - Fernando Beltramo
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America; University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America
| | - Lara Nelson
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America; University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America
| | - Shilpa Shah
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America; University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America
| | - Anoopindar Bhalla
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America; University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America
| | - Martha A Q Curley
- Children's Hospital Philadelphia, University of Pennsylvania, United States of America
| | - Christopher J L Newth
- Children's Hospital Los Angeles, Department of Anesthesiology and Critical Care, United States of America; University of Southern California, Keck School of Medicine, Department of Pediatrics, United States of America
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Laveneziana P, Albuquerque A, Aliverti A, Babb T, Barreiro E, Dres M, Dubé BP, Fauroux B, Gea J, Guenette JA, Hudson AL, Kabitz HJ, Laghi F, Langer D, Luo YM, Neder JA, O'Donnell D, Polkey MI, Rabinovich R, Rossi A, Series F, Similowski T, Spengler C, Vogiatzis I, Verges S. ERS statement on respiratory muscle testing at rest and during exercise. Eur Respir J 2019; 53:13993003.01214-2018. [DOI: 10.1183/13993003.01214-2018] [Citation(s) in RCA: 227] [Impact Index Per Article: 45.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 02/18/2019] [Indexed: 12/12/2022]
Abstract
Assessing respiratory mechanics and muscle function is critical for both clinical practice and research purposes. Several methodological developments over the past two decades have enhanced our understanding of respiratory muscle function and responses to interventions across the spectrum of health and disease. They are especially useful in diagnosing, phenotyping and assessing treatment efficacy in patients with respiratory symptoms and neuromuscular diseases. Considerable research has been undertaken over the past 17 years, since the publication of the previous American Thoracic Society (ATS)/European Respiratory Society (ERS) statement on respiratory muscle testing in 2002. Key advances have been made in the field of mechanics of breathing, respiratory muscle neurophysiology (electromyography, electroencephalography and transcranial magnetic stimulation) and on respiratory muscle imaging (ultrasound, optoelectronic plethysmography and structured light plethysmography). Accordingly, this ERS task force reviewed the field of respiratory muscle testing in health and disease, with particular reference to data obtained since the previous ATS/ERS statement. It summarises the most recent scientific and methodological developments regarding respiratory mechanics and respiratory muscle assessment by addressing the validity, precision, reproducibility, prognostic value and responsiveness to interventions of various methods. A particular emphasis is placed on assessment during exercise, which is a useful condition to stress the respiratory system.
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8
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Song Y, Dahl M, Leavitt W, Alvord J, Bradford CY, Albertine KH, Pillow JJ. Vitamin A Protects the Preterm Lamb Diaphragm Against Adverse Effects of Mechanical Ventilation. Front Physiol 2018; 9:1119. [PMID: 30150942 PMCID: PMC6099107 DOI: 10.3389/fphys.2018.01119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 07/25/2018] [Indexed: 11/13/2022] Open
Abstract
Background: Preterm infants are deficient in vitamin A, which is essential for growth and development of the diaphragm. Preterm infants often require mechanical ventilation (MV) for respiratory distress. In adults, MV is associated with the development of ventilation-induced diaphragm dysfunction and difficulty weaning from the ventilator. We assessed the impact of MV on the preterm diaphragm and the protective effect of vitamin A during MV. Methods: Preterm lambs delivered operatively at ∼131 days gestation (full gestation: 150 days) received respiratory support by synchronized intermittent mandatory ventilation for 3 days. Lambs in the treated group received daily (24 h) enteral doses of 2500 IU/kg/day vitamin A combined with 250 IU/kg/day retinoic acid (VARA) during MV, while MV control lambs received saline. Unventilated fetal reference lambs were euthanized at birth, without being allowed to breathe. The fetal diaphragm was collected to quantify mRNA levels of myosin heavy chain (MHC) isoforms, atrophy genes, antioxidant genes, and pro-inflammatory genes; to determine ubiquitin proteasome pathway activity; to measure the abundance of protein carbonyl, and to investigate metabolic signaling. Results: Postnatal MV significantly decreased expression level of the neonatal MHC gene but increased expression level of MHC IIx mRNA level (p < 0.05). Proteasome activity increased after 3 days MV, accompanied by increased MuRF1 mRNA level and accumulated protein carbonyl abundance. VARA supplementation decreased proteasome activity and FOXO1 signaling, down-regulated MuRF1 expression, and reduced reactive oxidant production. Conclusion: These findings suggest that 3 days of MV results in abnormal myofibrillar composition, activation of the proteolytic pathway, and oxidative injury of diaphragms in mechanically ventilated preterm lambs. Daily enteral VARA protects the preterm diaphragm from these adverse effects.
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Affiliation(s)
- Yong Song
- School of Human Sciences, The University of Western Australia, Crawley, WA, Australia.,Centre for Neonatal Research and Education, Division of Paediatrics and Child Health, Medical School, The University of Western Australia, Crawley, WA, Australia.,School of Public Health, Curtin University, Bentley, WA, Australia.,Centre for Genetic Origins of Health and Disease, The University of Western Australia, Curtin University, Crawley, WA, Australia
| | - MarJanna Dahl
- Department of Pediatrics, University of Utah, Salt Lake City, UT, United States
| | - Wendy Leavitt
- Department of Pediatrics, University of Utah, Salt Lake City, UT, United States
| | - Jeremy Alvord
- Department of Pediatrics, University of Utah, Salt Lake City, UT, United States
| | - Calan Y Bradford
- Department of Pediatrics, University of Utah, Salt Lake City, UT, United States
| | - Kurt H Albertine
- Department of Pediatrics, University of Utah, Salt Lake City, UT, United States
| | - J Jane Pillow
- School of Human Sciences, The University of Western Australia, Crawley, WA, Australia.,Centre for Neonatal Research and Education, Division of Paediatrics and Child Health, Medical School, The University of Western Australia, Crawley, WA, Australia
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9
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Dassios T, Kaltsogianni O, Dixon P, Greenough A. Effect of maturity and infection on the rate of relaxation of the respiratory muscles in ventilated, newborn infants. Acta Paediatr 2018; 107:587-592. [PMID: 29243318 DOI: 10.1111/apa.14188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 11/08/2017] [Accepted: 12/07/2017] [Indexed: 11/26/2022]
Abstract
AIM To assess the respiratory muscle time constant of relaxation (τ), an index of respiratory muscle function in ventilated newborns. METHODS Sixty-two infants (42 born prematurely) with a median gestational age of 29 [interquartile range (IQR) 26-37] weeks were prospectively studied. Measurement of τ was taken during spontaneous breathing on endotracheal continuous positive airway pressure prior to extubation, and τ was calculated from the reciprocal of the slope of the airway pressure decline versus time. Infants were classified as having had systemic or respiratory infection (positive microbiology) if they had any positive bacterial blood or respiratory culture prior to measurement. RESULTS Measurement of τ was taken at a median post-natal age of 6 (IQR 3-29) days. The median τ was higher in premature infants [17.4 (IQR 7.7-28.3) sec/cmH2 O] compared to term infants [6.8 (IQR 4.4-8.7) sec/cmH2 O, p < 0.001]. The median τ was higher in infants who had had positive microbiology [17.6 (IQR 9.9-29.1) sec/cmH2 O] compared to infants with negative microbiology [8.0 (IQR 6.3-17.9) sec/cmH2 O, p = 0.034]. τ was related to gestational age (r = -0.265, p = 0.003) and weight at measurement (r = -0.269, p = 0.002). CONCLUSION Respiratory muscle function in ventilated newborns is negatively affected by prematurity and previous systemic or respiratory infection.
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Affiliation(s)
- Theodore Dassios
- Neonatal Intensive Care Centre; King's College Hospital NHS Foundation Trust; London UK
| | - Ourania Kaltsogianni
- Neonatal Intensive Care Centre; King's College Hospital NHS Foundation Trust; London UK
| | | | - Anne Greenough
- Division of Asthma, Allergy and Lung Biology; MRC & Asthma UK Centre in Allergic Mechanisms of Asthma; King's College London; London UK
- NIHR Biomedical Centre at Guy's and St Thomas NHS Foundation Trust and King's College London; London UK
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10
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Karisnan K, Mahzabin T, Bakker AJ, Song Y, Noble PB, Pillow JJ, Pinniger GJ. Gestational age at time of in utero lipopolysaccharide exposure influences the severity of inflammation-induced diaphragm weakness in lambs. Am J Physiol Regul Integr Comp Physiol 2017; 314:R523-R532. [PMID: 29212808 DOI: 10.1152/ajpregu.00150.2017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The preterm diaphragm is functionally immature compared with its term counterpart. In utero inflammation further exacerbates preterm diaphragm dysfunction. We hypothesized that preterm lambs are more vulnerable to in utero inflammation-induced diaphragm dysfunction compared with term lambs. Pregnant ewes received intra-amniotic (IA) injections of saline or 10 mg lipopolysaccharide (LPS) 2 or 7 days before delivery at 121 days (preterm) or ∼145 days (term) of gestation. Diaphragm contractile function was assessed in vitro. Plasma cytokines, diaphragm myosin heavy chain (MHC) isoforms, and oxidative stress were evaluated. Maximum diaphragm force in preterm control lambs was significantly lower (22%) than in term control lambs ( P < 0.001). Despite similar inflammatory cytokine responses to in utero LPS exposure, diaphragm function in preterm and term lambs was affected differentially. In term lambs, maximum force after a 2-day LPS exposure was significantly lower than in controls (by ~20%, P < 0.05). In preterm lambs, maximum forces after 2-day and 7-day LPS exposures were significantly lower than in controls (by ~30%, P < 0.05). Peak twitch force after LPS exposure was significantly lower in preterm than in controls, but not in term lambs. In term lambs, LPS exposure increased the proportion of MHC-I fibers, increased twitch contraction times, and increased fatigue resistance relative to controls. In preterm diaphragm, the cross-sectional area of embryonic MHC fibers was significantly lower after 7-day versus 2-day LPS exposures. We conclude that preterm lambs are more vulnerable to IA LPS-induced diaphragm dysfunction than term lambs. In utero inflammation exacerbates diaphragm dysfunction and may increase susceptibility to postnatal respiratory failure.
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Affiliation(s)
- Kanakeswary Karisnan
- School of Human Sciences, The University of Western Australia , Crawley , Australia.,School of Medicine, Perdana University -Royal College of Surgeons in Ireland , Selangor , Malaysia
| | - Tanzila Mahzabin
- School of Human Sciences, The University of Western Australia , Crawley , Australia
| | - Anthony J Bakker
- School of Human Sciences, The University of Western Australia , Crawley , Australia
| | - Yong Song
- School of Human Sciences, The University of Western Australia , Crawley , Australia.,Centre for Neonatal Research and Education, School of Paediatrics and Child Health, The University of Western Australia , Crawley , Australia.,School of Medicine, Perdana University -Royal College of Surgeons in Ireland , Selangor , Malaysia
| | - Peter B Noble
- School of Human Sciences, The University of Western Australia , Crawley , Australia.,Centre for Neonatal Research and Education, School of Paediatrics and Child Health, The University of Western Australia , Crawley , Australia
| | - J Jane Pillow
- School of Human Sciences, The University of Western Australia , Crawley , Australia.,Centre for Neonatal Research and Education, School of Paediatrics and Child Health, The University of Western Australia , Crawley , Australia
| | - Gavin J Pinniger
- School of Human Sciences, The University of Western Australia , Crawley , Australia
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Risk Factors for Pediatric Extubation Failure: The Importance of Respiratory Muscle Strength. Crit Care Med 2017; 45:e798-e805. [PMID: 28437378 DOI: 10.1097/ccm.0000000000002433] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE Respiratory muscle weakness frequently develops during mechanical ventilation, although in children there are limited data about its prevalence and whether it is associated with extubation outcomes. We sought to identify risk factors for pediatric extubation failure, with specific attention to respiratory muscle strength. DESIGN Secondary analysis of prospectively collected data. SETTING Tertiary care PICU. PATIENTS Four hundred nine mechanically ventilated children. INTERVENTIONS Respiratory measurements using esophageal manometry and respiratory inductance plethysmography were made preextubation during airway occlusion and on continuous positive airway pressure of 5 and pressure support of 10 above positive end-expiratory pressure 5 cm H2O, as well as 5 and 60 minutes postextubation. MEASUREMENTS AND MAIN RESULTS Thirty-four patients (8.3%) were reintubated within 48 hours of extubation. Reintubation risk factors included lower maximum airway pressure during airway occlusion (aPiMax) preextubation, longer length of ventilation, postextubation upper airway obstruction, high respiratory effort postextubation (pressure rate product, pressure time product, tension time index), and high postextubation phase angle. Nearly 35% of children had diminished respiratory muscle strength (aPiMax ≤ 30 cm H2O) at the time of extubation, and were nearly three times more likely to be reintubated than those with preserved strength (aPiMax > 30 cm H2O; 14% vs 5.5%; p = 0.006). Reintubation rates exceeded 20% when children with low aPiMax had moderately elevated effort after extubation (pressure rate product > 500), whereas children with preserved aPiMax had reintubation rates greater than 20% only when postextubation effort was very high (pressure rate product > 1,000). When children developed postextubation upper airway obstruction, reintubation rates were 47.4% for those with low aPiMax compared to 15.4% for those with preserved aPiMax (p = 0.02). Multivariable risk factors for reintubation included acute neurologic disease, lower aPiMax, postextubation upper airway obstruction, higher preextubation positive end-expiratory pressure, higher postextubation pressure rate product, and lower height. CONCLUSIONS Neuromuscular weakness at the time of extubation was common in children and was independently associated with reintubation, particularly when postextubation effort was high.
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Karisnan K, Bakker AJ, Song Y, Noble PB, Pillow JJ, Pinniger GJ. Gestational age at initial exposure toin uteroinflammation influences the extent of diaphragm dysfunction in preterm lambs. Respirology 2015; 20:1255-62. [DOI: 10.1111/resp.12615] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 05/19/2015] [Accepted: 06/28/2015] [Indexed: 01/27/2023]
Affiliation(s)
- Kanakeswary Karisnan
- School of Anatomy, Physiology and Human Biology; University of Western Australia; Perth Western Australia Australia
| | - Anthony J. Bakker
- School of Anatomy, Physiology and Human Biology; University of Western Australia; Perth Western Australia Australia
- Centre for Neonatal Research and Education; School of Paediatrics and Child Health; University of Western Australia; Perth Western Australia Australia
| | - Yong Song
- School of Anatomy, Physiology and Human Biology; University of Western Australia; Perth Western Australia Australia
| | - Peter B. Noble
- School of Anatomy, Physiology and Human Biology; University of Western Australia; Perth Western Australia Australia
| | - J. Jane Pillow
- School of Anatomy, Physiology and Human Biology; University of Western Australia; Perth Western Australia Australia
- Centre for Neonatal Research and Education; School of Paediatrics and Child Health; University of Western Australia; Perth Western Australia Australia
| | - Gavin Jon Pinniger
- School of Anatomy, Physiology and Human Biology; University of Western Australia; Perth Western Australia Australia
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Karisnan K, Bakker AJ, Song Y, Noble PB, Pillow JJ, Pinniger GJ. Interleukin-1 receptor antagonist protects against lipopolysaccharide induced diaphragm weakness in preterm lambs. PLoS One 2015; 10:e0124390. [PMID: 25860718 PMCID: PMC4393095 DOI: 10.1371/journal.pone.0124390] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 03/13/2015] [Indexed: 12/21/2022] Open
Abstract
Chorioamnionitis (inflammation of the fetal membranes) is strongly associated with preterm birth and in utero exposure to inflammation significantly impairs contractile function in the preterm lamb diaphragm. The fetal inflammatory response to intra-amniotic (IA) lipopolysaccharide (LPS) is orchestrated via interleukin 1 (IL-1). We aimed to determine if LPS induced contractile dysfunction in the preterm diaphragm is mediated via the IL-1 pathway. Pregnant ewes received IA injections of recombinant human IL-1 receptor antagonist (rhIL-1ra) (Anakinra; 100 mg) or saline (Sal) 3 h prior to second IA injections of LPS (4 mg) or Sal at 119d gestational age (GA). Preterm lambs were killed after delivery at 121d GA (term = 150 d). Muscle fibres dissected from the right hemi-diaphragm were mounted in an in vitro muscle test system for assessment of contractile function. The left hemi-diaphragm was snap frozen for molecular and biochemical analyses. Maximum specific force in lambs exposed to IA LPS (Sal/LPS group) was 25% lower than in control lambs (Sal/Sal group; p=0.025). LPS-induced diaphragm weakness was associated with higher plasma IL-6 protein, diaphragm IL-1β mRNA and oxidised glutathione levels. Pre-treatment with rhIL-1ra (rhIL-1ra/LPS) ameliorated the LPS-induced diaphragm weakness and blocked systemic and local inflammatory responses, but did not prevent the rise in oxidised glutathione. These findings indicate that LPS induced diaphragm dysfunction is mediated via IL-1 and occurs independently of oxidative stress. Therefore, the IL-1 pathway represents a potential therapeutic target in the management of impaired diaphragm function in preterm infants.
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Affiliation(s)
- Kanakeswary Karisnan
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Crawley, WA, Australia
| | - Anthony J. Bakker
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Crawley, WA, Australia
| | - Yong Song
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Crawley, WA, Australia
- Centre for Neonatal Research and Education, School of Paediatrics and Child Health, University of Western Australia, Crawley, WA, Australia
| | - Peter B. Noble
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Crawley, WA, Australia
- Centre for Neonatal Research and Education, School of Paediatrics and Child Health, University of Western Australia, Crawley, WA, Australia
| | - J. Jane Pillow
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Crawley, WA, Australia
- Centre for Neonatal Research and Education, School of Paediatrics and Child Health, University of Western Australia, Crawley, WA, Australia
| | - Gavin J. Pinniger
- School of Anatomy, Physiology and Human Biology, University of Western Australia, Crawley, WA, Australia
- * E-mail:
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14
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Song Y, Demmer DL, Pinniger GJ, Lavin T, MacMillan MV, Pillow JJ, Bakker AJ. Effect of maternal steroid on developing diaphragm integrity. PLoS One 2014; 9:e93224. [PMID: 24681552 PMCID: PMC3969349 DOI: 10.1371/journal.pone.0093224] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Accepted: 03/03/2014] [Indexed: 01/21/2023] Open
Abstract
Antenatal steroids reduce the severity of initial respiratory distress of premature newborn babies but may have an adverse impact on other body organs. The study aimed to examine the effect of maternal steroids on postnatal respiratory muscle function during development and elucidate the mechanisms underlying the potential myopathy in newborn rats. Pregnant rats were treated with intramuscular injections of 0.5 mg/kg betamethasone 7 d and 3 d before birth. Newborn diaphragms were dissected for assessment of contractile function at 2 d, 7 d or 21 d postnatal age (PNA), compared with age-matched controls. The expression of myosin heavy chain (MHC) isoforms and atrophy-related genes and activity of intracellular molecular signalling were measured using quantitative PCR and/or Western blot. With advancing PNA, neonatal MHC gene expression decreased progressively while MHC IIb and IIx isoforms increased. Protein metabolic signalling showed high baseline activity at 2 d PNA, and significantly declined at 7 d and 21 d. Antenatal administration of betamethasone significantly decreased diaphragm force production, fatigue resistance, total fast fibre content and anabolic signalling activity (Akt and 4E-BP1) in 21 d diaphragm. These responses were not observed in 2 d or 7 d postnatal diaphragm. Results demonstrate that maternal betamethasone treatment causes postnatal diaphragmatic dysfunction at 21 d PNA, which is attributed to MHC II protein loss and impairment of the anabolic signalling pathway. Developmental modifications in MHC fibre composition and protein signalling account for the age-specific diaphragm dysfunction.
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Affiliation(s)
- Yong Song
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Neonatal Research and Education, School of Paediatrics and Child Health, The University of Western Australia, Perth, Western Australia, Australia
| | - Denise L. Demmer
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Perth, Western Australia, Australia
| | - Gavin J. Pinniger
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Perth, Western Australia, Australia
| | - Tina Lavin
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Neonatal Research and Education, School of Paediatrics and Child Health, The University of Western Australia, Perth, Western Australia, Australia
| | - Mia V. MacMillan
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Perth, Western Australia, Australia
| | - Jane J. Pillow
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Neonatal Research and Education, School of Paediatrics and Child Health, The University of Western Australia, Perth, Western Australia, Australia
- Women and Newborns Health Service, c/-King Edward Memorial and Princess Margaret Hospitals, Perth, Western Australia, Australia
| | - Anthony J. Bakker
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Perth, Western Australia, Australia
- * E-mail:
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15
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Song Y, Karisnan K, Noble PB, Berry CA, Lavin T, Moss TJM, Bakker AJ, Pinniger GJ, Pillow JJ. In utero LPS exposure impairs preterm diaphragm contractility. Am J Respir Cell Mol Biol 2013; 49:866-74. [PMID: 23795611 DOI: 10.1165/rcmb.2013-0107oc] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Preterm birth is associated with inflammation of the fetal membranes (chorioamnionitis). We aimed to establish how chorioamnionitis affects the contractile function and phenotype of the preterm diaphragm. Pregnant ewes received intra-amniotic injections of saline or 10 mg LPS, 2 days or 7 days before delivery at 121 days of gestation (term = 150 d). Diaphragm strips were dissected for the assessment of contractile function after terminal anesthesia. The inflammatory cytokine response, myosin heavy chain (MHC) fibers, proteolytic pathways, and intracellular molecular signaling were analyzed using quantitative PCR, ELISA, immunofluorescence staining, biochemical assays, and Western blotting. Diaphragm peak twitch force and maximal tetanic force were approximately 30% lower than control values in the 2-day and 7-day LPS groups. Activation of the NF-κB pathway, an inflammatory response, and increased proteasome activity were observed in the 2-day LPS group relative to the control or 7-day LPS group. No inflammatory response was evident after a 7-day LPS exposure. Seven-day LPS exposure markedly decreased p70S6K phosphorylation, but no effect on other signaling pathways was evident. The proportion of MHC IIa fibers was lower than that for control samples in the 7-day LPS group. MHC I fiber proportions did not differ between groups. These results demonstrate that intrauterine LPS impairs preterm diaphragmatic contractility after 2-day and 7-day exposures. Diaphragm dysfunction, resulting from 2-day LPS exposure, was associated with a transient activation of proinflammatory signaling, with subsequent increased atrophic gene expression and enhanced proteasome activity. Persistently impaired contractility for the 7-day LPS exposure was associated with the down-regulation of a key component of the protein synthetic signaling pathway and a reduction in the proportions of MHC IIa fibers.
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Affiliation(s)
- Yong Song
- 1 School of Anatomy, Physiology, and Human Biology, and
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16
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Lavin T, Song Y, Bakker AJ, McLean CJ, Macdonald WA, Noble PB, Berry CA, Pillow JJ, Pinniger GJ. Developmental changes in diaphragm muscle function in the preterm and postnatal lamb. Pediatr Pulmonol 2013; 48:640-8. [PMID: 23401383 DOI: 10.1002/ppul.22762] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 11/27/2012] [Indexed: 11/12/2022]
Abstract
RATIONALE The preterm diaphragm is structurally and functionally immature, potentially contributing to an increased risk of respiratory distress and failure. We investigated developmental changes in contractile function and susceptibility to fatigue of the costal diaphragm in the fetal lamb to understand factors contributing to the risk of developing diaphragm dysfunction and respiratory disorders. We hypothesized that the functional capacity of the diaphragm will vary with maturational stage as will its susceptibility to fatigue. METHODS Lambs were studied at 75, 100, 125, 145, 154, 168, and 200 days postconceptional age (term = 147 days). Lambs were euthanized (sodium pentobarbitone, 100 mg/kg) either at delivery or immediately prior to post-mortem for postnatal lambs. Contractile function was assessed on longitudinal strips of intact muscle fibers and the remaining tissue frozen in liquid nitrogen for analysis of myosin heavy chain (MHC) mRNA expression and protein content. RESULTS Fetal development of diaphragm function was characterized by a significant increase in maximum specific force, increased susceptibility to fatigue, reduced twitch contraction times, and a progressive increase in MHCI and MHCII protein content. Postnatally, there was a progressive decrease in the susceptibility to fatigue that coincided with an increase in the MHC I:II protein ratio. CONCLUSION These data indicate that the functional capacity of the diaphragm varies with maturational age and may be an important determinant of the susceptibility to preterm respiratory failure.
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Affiliation(s)
- T Lavin
- School of Anatomy, Physiology, and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia
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Efthimiadis KG, Samaras T, Polyzoidis KS. Magnetic stimulation of the spine: the role of tissues and their modelling. Phys Med Biol 2010; 55:2541-53. [DOI: 10.1088/0031-9155/55/9/008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Affiliation(s)
- C Gaultier
- Service de Physiologie-Explorations Fonctionnelles, Université Paris VII, Hôpital Robert Debré, France.
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Abstract
Skeletal muscles are composed of fibres of different types, each type being identified by the isoform of myosin heavy chain which is expressed as slow 1, fast 2A, fast 2X, and fast 2B. Slow fibres are resistant to fatigue due to their highly oxidative metabolism whereas 2X and 2B fibres are easily fatiguable and fast 2A fibres exhibit intermediate fatigue resistance. Slow fibres and fast fibres are present in equal proportions in the adult human diaphragm while intercostal muscles contain a higher proportion of fast fibres. A small fibre size, abundance of capillaries, and a high aerobic oxidative enzyme activity are typical features of diaphragm fibres and give them the resistance to fatigue required by their continuous activity. Because of their fibre composition, intercostal muscles are less resistant to fatigue. The structural and functional characteristics of respiratory muscle fibres are not fixed, however, and can be modified in response to several physiological and pathological conditions such as training (adaptation to changes in respiratory load), adaptation to hypoxia, age related changes, and changes associated with respiratory diseases. The properties of respiratory muscle fibres can also be modified by pharmacological agents such as beta2 agonists and corticosteroids used for the treatment of respiratory diseases.
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Affiliation(s)
- B Polla
- Hospital S Biagio, Department of Pneumology, Alessandria, Italy.
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Dimitriou G, Greenough A, Kavvadia V, Davenport M, Nicolaides KH, Moxham J, Rafferty GF. Diaphragmatic function in infants with surgically corrected anomalies. Pediatr Res 2003; 54:502-8. [PMID: 12815114 DOI: 10.1203/01.pdr.0000081299.22005.f0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Infants with surgically correctable anomalies, abdominal wall defects (AWD) or congenital diaphragmatic hernia (CDH) may have poor postnatal diaphragmatic function, because the low intra-abdominal pressure experienced by such patients in utero could result in impaired diaphragmatic development. Our objective was to compare postoperative diaphragmatic function of infants with CDH or AWD to that of gestational age-matched controls. Diaphragmatic function was assessed by measurement of the transdiaphragmatic pressure and maximum inspiratory pressure at the mouth generated during crying against an occlusion. In addition, the transdiaphragmatic pressure produced by unilateral and/or bilateral magnetic stimulation of the phrenic nerves (TwPdi) was examined. Lung volume was assessed by measurement of functional residual capacity (FRC) using a helium gas dilution technique. Ten infants with CDH, 26 with AWD infants (19 gastroschisis, seven exomphalos), and 36 gestational age-matched controls were studied. Compared with their matched controls, the eight CDH infants with left-sided defects had significantly lower left (p < 0.01) and right (p < 0.05) TwPdi and FRC (p < 0.01), and the gastroschisis infants, but not those with exomphalos, had significantly lower left and right TwPdi (p < 0.05). There were no significant differences in transdiaphragmatic pressure and maximum inspiratory pressure at the mouth between the CDH or AWD infants and the controls. Diaphragmatic function postoperatively is impaired in infants with CDH or gastroschisis.
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Affiliation(s)
- Gabriel Dimitriou
- Department of Child Health, Guy's, King's, and St Thomas' School of Medicine, Children Nationwide Regional Neonatal Intensive Care Centre, King's College London, SE5 9RS, United Kingdom
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