Immediate postnatal prediction of death or bronchopulmonary dysplasia among very preterm and very low birth weight infants based on gradient boosting decision trees algorithm: A nationwide database study in Japan.

INTRODUCTION: Bronchopulmonary dysplasia (BPD) poses a substantial global health burden. Individualized treatment strategies based on early prediction of the development of BPD can mitigate preterm birth complications; however, previously suggested predictive models lack early postnatal applicability. We aimed to develop predictive models for BPD and mortality based on immediate postnatal clinical data. METHODS: Clinical information on very preterm and very low birth weight infants born between 2008 and 2018 was extracted from a nationwide Japanese database. The gradient boosting decision trees (GBDT) algorithm was adopted to predict BPD and mortality, using predictors within the first 6 h postpartum. We assessed the temporal validity and evaluated model adequacy using Shapley additive explanations (SHAP) values. RESULTS: We developed three predictive models using data from 39,488, 39,096, and 40,291 infants to predict "death or BPD," "death or severe BPD," and "death before discharge," respectively. These well-calibrated models achieved areas under the receiver operating characteristic curve of 0.828 (95% CI: 0.828-0.828), 0.873 (0.873-0.873), and 0.887 (0.887-0.888), respectively, outperforming the multivariable logistic regression models. SHAP value analysis identified predictors of BPD, including gestational age, size at birth, male sex, and persistent pulmonary hypertension. In SHAP value-based case clustering, the "death or BPD" prediction model stratified infants by gestational age and persistent pulmonary hypertension, whereas the other models for "death or severe BPD" and "death before discharge" commonly formed clusters of low mortality, extreme prematurity, low Apgar scores, and persistent pulmonary hypertension of the newborn. CONCLUSIONS: GBDT models for predicting BPD and mortality, designed for use within 6 h postpartum, demonstrated superior prognostic performance. SHAP value-based clustering, a data-driven approach, formed clusters of clinical relevance. These findings suggest the efficacy of a GBDT algorithm for the early postnatal prediction of BPD.

Echocardiography Assessment of Left Ventricular Function in Extremely Preterm Infants, Born at Less Than 28 Weeks' Gestation, With Bronchopulmonary Dysplasia and Systemic Hypertension.

BACKGROUND: The survival of smaller and more immature premature infants has been associated with lifelong cardiorespiratory comorbidities. Infants with bronchopulmonary dysplasia (BPD) undergo routine screening echocardiography to evaluate for development of chronic pulmonary hypertension, a late manifestation of pulmonary vascular disease. METHODS: Our aim was to evaluate left ventricular (LV) performance in infants with BPD and pulmonary vascular disease who developed systemic hypertension. We hypothesized that infants with hypertension were more likely to have impaired LV performance. We present a single-center cross-sectional study of premature infants born at less than 28 0/7 weeks' gestational age with a clinical diagnosis of BPD. Infants were categorized by the systolic arterial pressure (SAP) at time of echocardiography as hypertensive (SAP ≥90 mm Hg) or normotensive (SAP <90 mm Hg). Sixty-four patients were included. RESULTS: Infants with hypertension showed altered LV diastolic function with prolonged tissue Doppler imaging-derived isovolumic relaxation time (54.2 ± 5.1 vs 42.9 ± 8.2, P < .001), lower E:A, and higher E:e'. Indices of left heart volume/pressure loading (left atrium:aorta and LV end-diastolic volume [6.1 ± 2 vs 4.2 ± 1.2, P < .001]) were also higher in the hypertensive group. Finally, infants in the hypertensive group had higher pulmonary vascular resistance index (4.42 ± 1.1 vs 3.69 ± 0.8, P = .004). CONCLUSIONS: We conclude that extremely preterm infants with BPD who develop systemic hypertension are at risk of abnormal LV diastolic dysfunction. Increased pulmonary vascular resistance index in the hypertensive group may relate to pulmonary venous hypertension secondary to LV dysfunction. This is an important consideration in this cohort when selecting the physiologically most appropriate treatment.

Comparison of Pneumotachometer and Portable Digital Turbine Spirometry for Field-Based Assessment: An Air Quality, Environment, and Respiratory Outcomes in Bronchopulmonary Dysplasia Study.

Introduction: Data on the use of remote spirometry are limited in the pediatric population. We sought to assess the feasibility and accuracy of a digital turbine spirometer, Medical International Research (MIR) Spirobank Smart (MIR, New Berlin, WI, USA), compared with a pneumotachography spirometer, Pneumotrac (Vitalograph Inc., Lenexa, KS, USA), in field-based clinical research. Methods: This is a cross-sectional study of a subgroup of school-aged participants enrolled in the Air quality, Environment, and Respiratory Outcomes in Bronchopulmonary Dysplasia (BPD) study, who performed same-day paired coached baseline spirometry measurements from the Pneumotrac and MIR devices. Proportion of successful tests was estimated for each device and compared using McNemar's test. Correlation between devices forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) was analyzed by Lin's concordance correlation, and Bland-Altman plots were generated. Results: Twenty-one participants with history of BPD completed home spirometry maneuvers on both devices. The mean age of participants was 8.7 years. The mean FEV1 and FVC measurement was 81% predicted and 90.4% predicted, respectively. The proportion of acceptable tests appeared higher using Pneumotrac (81%) than when using MIR (67%), although without evidence of discordance (P = 0.317). Among subjects with successful tests on both devices, Lin's concordance correlation demonstrated moderate agreement (FEV1 r = 0.955, 95% confidence interval [CI]: 0.87-0.98; FVC r = 0.971, CI: 0.91-0.99). The mean difference in FEV1 between Pneumotrac and MIR was 0.079 L (95% limits of agreement were -0.141 to 0.298 L) and FVC was 0.075 L (95% limits of agreement were -0.171 to 0.322 L). These were relatively small and without evidence of systematic or volume-dependent bias. Conclusions: Utilizing turbine spirometers may be a promising and feasible way to perform pulmonary function testing for field research in children.

Specificity of International Classification of Diseases codes for bronchopulmonary dysplasia: an investigation using electronic health record data and a large insurance database.

OBJECTIVE: International Classification of Diseases (ICD) codes in electronic health records (EHRs) are increasingly used for health services research, in spite of unknown diagnostic accuracy. The accuracy of ICD codes to identify bronchopulmonary dysplasia (BPD) is unknown. STUDY DESIGN: Retrospective cohort study in a single-center NICU (n = 166) to evaluate sensitivity and specificity of ICD-10 codes for the diagnosis of BPD. Analysis of large insurance claims database (n = 7887) to determine date of assignment of the code. RESULTS: The sensitivity of any BPD-related ICD codes ranged from 0.82 to 0.95, while the specificity ranged from 0.25 to 0.36. In a large national insurance database, the most common date of ICD-9 or ICD-10 code assignment was the day of birth, which is inconsistent with the clinical definition. CONCLUSIONS: ICD codes registered for BPD are unlikely to accurately reflect the current clinical definition and should be interpreted with caution.

Association between Policy Changes for Oxygen Saturation Alarm Settings and Neonatal Morbidity and Mortality in Infants Born Very Preterm.

OBJECTIVE: To determine the impact of policy changes for pulse oximetry oxygen saturation (SpO2) alarm limits on neonatal mortality and morbidity among infants born very preterm. STUDY DESIGN: This was a retrospective cohort study of infants born very preterm in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Infants were classified based on treatment at a hospital with an SpO2 alarm policy change and study epoch (before vs after policy change). We used a generalized linear mixed model to determine the effect of hospital group and epoch on the primary outcomes of mortality and severe retinopathy of prematurity (ROP) and secondary outcomes of necrotizing enterocolitis, bronchopulmonary dysplasia, and any ROP. RESULTS: There were 3809 infants in 10 hospitals with an SpO2 alarm policy change and 3685 infants in 9 hospitals without a policy change. The nature of most policy changes was to narrow the SpO2 alarm settings. Mortality was lower in hospitals without a policy change (aOR 0.63; 95% CI 0.50-0.80) but did not differ between epochs in policy change hospitals. The odds of bronchopulmonary dysplasia were greater for hospitals with a policy change (aOR 1.65; 95% CI 1.36-2.00) but did not differ for hospitals without a policy change. Severe ROP and necrotizing enterocolitis did not differ between epochs for either group. The adjusted odds of any ROP were lower in recent years in both hospital groups. CONCLUSIONS: Changing SpO2 alarm policies was not associated with reduced mortality or increased severe ROP among infants born very preterm.

Non-invasive assessment of oxidative stress in preterm infants.

Preterm newborns have an immature antioxidant defense system and are especially susceptible to oxidative stress. Resuscitation, mechanical ventilation, intermittent hypoxia and apneic episodes require frequently oxygen supplementation which leads to oxidative stress in preterm newborns. The consequences of oxidative damage are increased short and long-term morbidities, neurodevelopmental impairment and increased mortality. Oxidative stress biomarkers are determined in blood samples from preterm children during their stay in neonatal intensive care units especially for research purposes. However, there is a tendency towards reducing invasive and painful techniques in the NICU (Neonatal Intensive Care Unit) and avoiding excessive blood extractions procedures. In this paper, it has been described some studies that employed non-invasive samples to determine oxidative stress biomarkers form preterm infants in order to perform a close monitoring biomarker with a significant greater predictive value. Among these methods we describe a previously developed and validated high-performance liquid chromatography tandem mass spectrometry method that allow to accurately determine the most reliable biomarkers in biofluids, which are non-invasively and painlessly obtained.

Neonatal Outcomes Based on Duration of Exposure to Antenatal Corticosteroids in Indicated Preterm Deliveries.

OBJECTIVE: To evaluate how duration of exposure to antenatal corticosteroids (ACSs) prior to delivery affects neonatal outcomes in indicated preterm deliveries. STUDY DESIGN: This is a retrospective cohort of all indicated singleton preterm deliveries (23-34 weeks) in a single tertiary center from 2011 to 2014 comparing those who received ACS 2 to 7 days versus >7 days prior to delivery. The primary neonatal outcome was a composite of arterial cord pH < 7 or base excess ≤ 12, 5-minute Apgar ≤ 3, cardiopulmonary resuscitation, culture-proven neonatal sepsis, intraventricular hemorrhage grade III/IV, necrotizing enterocolitis, and neonatal death. Analyses were stratified by delivering gestational age (230/7-276/7, 280/7-316/7, and 320/7-336/7 weeks). Multivariate logistic regression refined point estimates and adjusted for confounders. RESULTS: In total, 301 women delivered >48 hours after initial ACS dose, 230 delivered within 2 to 7 days, and 71 delivered >7 days. Infants with an interval of >7 days had no significant increase in the unadjusted composite neonatal outcome (p = 0.42), but when adjusted, the composite neonatal outcome (adjusted odds ratio [AOR]: 2.7; 95% confidence interval [CI]: 1.18-6.31) and neonatal death (AOR: 4.20; 95% CI: 1.39-12.69) were significantly increased with an ACS interval of >7 day. CONCLUSION: In this cohort, the benefit of ACS diminished >7 days after administration, particularly when delivery occurred at <32 weeks.

Phenotypic assessment of pulmonary hypertension using high-resolution echocardiography is feasible in neonatal mice with experimental bronchopulmonary dysplasia and pulmonary hypertension: a step toward preventing chronic obstructive pulmonary disease.

Bronchopulmonary dysplasia (BPD) and chronic obstructive pulmonary disease (COPD) are chronic lung diseases of human infants and adults, respectively, that are characterized by alveolar simplification. One-third of the infants with severe BPD develop pulmonary hypertension (PH). More importantly, PH increases morbidity and mortality in BPD patients. Additionally, COPD is a common respiratory morbidity in former BPD patients. The lack of an appropriate small animal model wherein echocardiography (Echo) can demonstrate PH is one of the major barriers to understand the molecular mechanisms of the disease and, thereby, develop rational therapies to prevent and/or treat PH in BPD patients. Thus, the goal of this study was to establish a model of experimental BPD and PH and investigate the feasibility of Echo to diagnose PH in neonatal mice. Since hyperoxia-induced oxidative stress and inflammation contributes to the development of BPD with PH, we tested the hypothesis that exposure of newborn C57BL/6J mice to 70% O2 (hyperoxia) for 14 days leads to lung oxidative stress, inflammation, alveolar and pulmonary vascular simplification, pulmonary vascular remodeling, and Echo evidence of PH. Hyperoxia exposure caused lung oxidative stress and inflammation as evident by increased malondialdehyde adducts and inducible nitric oxide synthase, respectively. Additionally, hyperoxia exposure caused growth restriction, alveolar and pulmonary vascular simplification, and pulmonary vascular remodeling. At 14 days of age, Echo of these mice demonstrated that hyperoxia exposure decreased pulmonary acceleration time (PAT) and PAT/ejection time ratio and increased right ventricular free wall thickness, which are indicators of significant PH. Thus, we have demonstrated the feasibility of Echo to phenotype PH in neonatal mice with experimental BPD with PH, which can aid in discovery of therapies to prevent and/or treat BPD with PH and its sequelae such as COPD in humans.

Assessment of pulmonary function in a follow-up of premature infants: our experience.

Respiratory diseases are a major cause of morbidity in neonates, especially preterm infants; a long term complication of prematurity such as bronchopulmonary dysplasia (BPD) is particularly relevant today. The exact role of the Pulmonary Function Test (PFT) in this area is not yet well defined; the PFT in newborns and infants - in contrast to what happens in uncooperative children and adults - are routinely used only in a few centers. The assessment of pulmonary function in newborns and infants, however, is nowadays possible with the same reliability that in cooperative patients with the possibility to extend the assessment of polmonary function from bench to bed. The assessment of pulmonary function must be carried out with non invasive and safe methods, at the bedside, with the possibility of continuous monitoring and providing adequate calculation and management of data. The ability to assess lung function helps to define the mechanisms of respiratory failure, improving the treatment and its effects and is therefore a useful tool in the follow-up of newborn and infant with pulmonary disease.

[Assessment of pulmonary function in a follow-up of premature infants: our experience]. / Valutazione della funzionalità respiratoria nell'ambito di un follow up respiratorio di neonati prematuri: la nostra esperienza.

Respiratory diseases are a major cause of morbidity in neonates, especially preterm infants; a long-term complication of prematurity such as bronchopulmonary dysplasia (BPD) is particularly relevant today. The exact role of the Pulmonary Function Test (PFT) in this area is not yet well defined; the PFT in newborns and infants--in contrast to what happens in uncooperative children and adults--are routinely used only in a few centers. The assessment of pulmonary function in newborns and infants, however, is nowadays possible with the same reliability that in cooperative patients with the possibility to extend the assessment of polmonary function from bench to bed. The assessment of pulmonary function must be carried out with non invasive and safe methods, at the bedside, with the possibility of continuous monitoring and providing adequate calculation and management of data. The ability to assess lung function helps to define the mechanisms of respiratory failure, improving the treatment and its effects and is therefore a useful tool in the follow-up of newborn and infant with pulmonary disease.

Scope and impact of early and late preterm infants admitted to the PICU with respiratory illness.

OBJECTIVE: To determine the clinical course and outcomes of children born early preterm (EPT, <32 weeks), late preterm (LPT, 32 to 35 weeks), and full term (FT, >or=36 weeks) who were subsequently admitted to the pediatric intensive care unit (PICU) with respiratory illness. STUDY DESIGN: Retrospective chart review of patients <2 years old admitted to a tertiary PICU with respiratory illness. RESULTS: Two hundred seventy-one patients met inclusion criteria: 17.3% were EPT, 12.2% were LPT, and 70.5% were FT. Lower respiratory tract infection was the most common diagnosis (55%) for all groups. Median PICU length of stay was longer for EPT (6.3 days) and LPT infants (7.1 days) compared with FT infants (3.7 days; P < .03 for both comparisons). EPT and LPT infants had longer hospital stays (median, 11.7 and 13.8 days, respectively) compared with FT infants (median, 7.1 days; P < .03 and P = .004, respectively). Median hospital charges were also greater for EPT ($85 151) and LPT ($83 576) groups compared with FT group ($55 122; P < .01 and P < .02, respectively). CONCLUSIONS: EPT and LPT infants comprise a considerable proportion of PICU admissions for respiratory illness and have greater resource utilization than FT infants.

Decreased incidence of bronchopulmonary dysplasia after early management changes, including surfactant and nasal continuous positive airway pressure treatment at delivery, lowered oxygen saturation goals, and early amino acid administration: a historical cohort study.

OBJECTIVE: The goal was to investigate the clinical impact of 3 early management practice changes for infants of < or = 1000 g. METHODS: We performed an historical cohort study of appropriately sized, preterm infants without congenital anomalies who were born between January 2001 and June 2002 (pre-early management practice change group; n = 87) and between July 2004 and December 2005 (post-early management practice change group; n = 76). RESULTS: Only 1 (1%) of 87 infants in the pre-early management practice change group received continuous positive airway pressure treatment in the first 24 hours of life, compared with 61 (80%) of 76 infants in the post-early management practice change group. The proportions of infants who required any synchronized intermittent mandatory ventilation during their hospital stays were 98.8% and 59.5%, respectively. The mean durations of synchronized intermittent mandatory ventilation were 35 days and 15 days, respectively. The combined incidence rates of moderate and severe bronchopulmonary dysplasia at corrected gestational age of 36 weeks were 43% and 24%, respectively. The use of vasopressor support for hypotension in the first 24 hours of life decreased from 39.1% (before early management practice changes) to 19.7% (after practice changes), the cumulative days of oxygen therapy decreased from 77 +/- 52 days to 56 +/- 47 days, and the proportions of infants discharged with home oxygen therapy decreased from 25.7% to 10.1%; the incidence of patent ductus arteriosus requiring surgical ligation increased from 1% to 10%. There were no differences in rates of death, intraventricular hemorrhage, periventricular leukomalacia, pneumothorax, necrotizing enterocolitis, or retinopathy of prematurity. CONCLUSIONS: Successful early management of extremely preterm infants with surfactant treatment followed by continuous positive airway pressure treatment at delivery, lowered oxygen saturation goals, and early amino acid supplementation is possible and is associated with reductions in the incidence and severity of bronchopulmonary dysplasia.

Follow-up care for infants with chronic lung disease: a randomized comparison of community- and center-based models.

OBJECTIVES: Premature infants with chronic lung disease benefit from comprehensive care, which typically is based in tertiary medical centers. When such centers are not easily accessible, alternative models of care are needed. The purpose of this work was to compare community-based follow-up, provided via telephone contacts, to traditional center-based follow-up of premature infants with chronic lung disease. PATIENTS AND METHODS: After discharge from neonatal intensive care, 150 premature infants with chronic lung disease were randomly assigned to either community-based (n = 75) or center-based (n = 75) follow-up. In community-based follow-up, a nurse specialist maintained telephone contact with the infant's primary caregiver and health care providers. Center-based follow-up consisted of visits to a medical center-based multidisciplinary clinic staffed by a neonatologist, a nurse specialist, and a social worker. The outcomes of interest were Bayley Scales of Infant Development mental developmental index and psychomotor developmental index, Vineland Adaptive Behavioral Composite, and growth delay (weight for length <5th percentile) at 1-year adjusted age and respiratory rehospitalizations through 1-year adjusted age. RESULTS: In each randomization group, 73 infants survived, and 69 were evaluated at 1-year adjusted age. The median mental development index (corrected for gestational age) was 90 for both groups. The median psychomotor developmental index was 82 for the center-based group and 81 for the community-based group. The median Vineland Adaptive Behavioral Composite was 100 and 102 for the center-based and community-based groups, respectively. In the center-based and community-based groups, respectively, the proportions with growth delay were 13% and 26%, and the proportions rehospitalized for respiratory illness were 33% and 29%. CONCLUSIONS: Infants randomly assigned to community-based, as compared with those randomly assigned to center-based follow-up, had similar developmental and health outcomes. The former approach might be a preferred alternative for families in rural settings or families for whom access to a tertiary care medical center is difficult.

Palivizumab: a review of its use as prophylaxis for serious respiratory syncytial virus infection.

Palivizumab (Synagi) is a humanized monoclonal antibody that provides immunoprophylaxis against serious lower respiratory tract infections (LRTIs) caused by respiratory syncytial virus (RSV). RSV is the leading cause of hospitalization for LRTIs in infants, causing winter- or wet-season epidemics. In two double-blind, placebo-controlled trials, intramuscular palivizumab 15 mg/kg every 30 days for 5 months significantly reduced RSV-related hospitalizations by 55% in 1502 infants with prematurity and/or bronchopulmonary dysplasia/chronic lung disease (BPD/CLD) and by 45% in 1287 infants with hemodynamically significant congenital heart disease (HSCHD). Reductions were statistically significant versus placebo in infants with BPD/CLD, with all degrees of prematurity, and with acyanotic/other heart disease. Palivizumab was generally well tolerated, with < or =1.9% of recipients discontinuing treatment for tolerability reasons. In placebo-controlled trials, the most common potentially drug-related adverse events were fever, nervousness, injection-site reactions, and diarrhea. Drug-related events occurred in 7.2-11% of palivizumab recipients in controlled trials (vs 6.9-10% with placebo) and 0-7.9% in open-label trials. Very few serious potentially drug-related adverse events occurred in clinical trials; four occurred in 2 of 285 patients in one open-label trial. No significant anti-palivizumab antibodies developed during palivizumab use. Palivizumab trough serum concentrations were below the recommended 40 microg/mL in about 33% and up to 14% of children prior to their second and third palivizumab injections. In pharmacoeconomic studies, the cost of palivizumab per hospitalization averted was generally lowest in the highest-risk infants. Drug cost was generally the most influential factor in sensitivity analyses. In conclusion, prophylaxis with palivizumab significantly reduces the incidence of RSV-related hospitalization relative to placebo and is generally well tolerated in high-risk infants aged <2 years, including those with prematurity and BPD/CLD or HSCHD, which are risk factors for early or serious RSV infection. Palivizumab is approved for use in these patients. Other high-risk infants in whom palivizumab has not been formally assessed, such as those with immunodeficiency, cystic fibrosis, or location-specific risk factors (including extended hospital stays) might potentially benefit from palivizumab. The use of palivizumab in these other high-risk populations is likely to be determined as much by pharmacoeconomic considerations as by efficacy outcomes.

Assessment of functional residual capacity using nitrogen washout and plethysmographic techniques in infants with and without bronchopulmonary dysplasia.

OBJECTIVE: In normal infants, functional residual capacity using plethysmography (FRCpleth) exceeds FRC(N2) (using nitrogen washout) and the within-subject difference FRC(pleth-N2) indicates the part of pulmonary gas volume not ventilated during tidal breathing. We postulated that infants with bronchopulmonary dysplasia (BPD) have an elevated FRC(pleth-N2). DESIGN: In a prospective study, FRC(pleth-N2) in healthy newborns (controls n = 17) was compared to that in neonates recovering from the respiratory distress syndrome without BPD (noBPD, studied at discharge, n = 13) and with BPD (BPD1 n = 14, studied at 36 post-conceptional weeks; BPD2 n = 16, at discharge). MEASUREMENTS AND RESULTS: Paired measurements, FRCpleth and FRC(N2), were performed using a plethysmograph (Jaeger, Germany) and an open-circuit nitrogen washout technique (SensorMedics 2600, USA). In comparison to the controls (5.2 ml/kg), FRC(pleth-N2)/kg in noBPD (12.7 ml/kg, p < 0.001), in BPD1 (24.9 ml/kg, p < 0.001) and in BPD2 (13.5 ml/kg, p < 0.001) was significantly higher. Compared with that of the controls FRCpleth was significantly increased in BPD1 (p < 0.001) and FRC(N2) was decreased in noBPD and both BPD groups. CONCLUSION: The FRC(pleth-N2) is a reliable indicator for pulmonary inhomogeneities in infants with respiratory diseases.

Approaching the management of the neonatal intensive care unit graduate through history and physical assessment.

NICU graduates, often ex-premature infants, offer unusual challenges to the primary care provider. History and physical assessment require an organized approach with meticulous attention to detail. These infants are at high risk for multiple problems including growth delays, nutrition and feeding problems, pulmonary sequelae, neurological sequelae and developmental delays, vision and hearing disturbances, as well as abnormalities in parent-infant bonding. This article emphasizes particular aspects of the history and physical examination that signify pathophysiology and sequelae common to the NICU graduate.

Whole-body plethysmography in the clinical assessment of infants with bronchopulmonary diseases.

Infant whole-body plethysmography offers a unique possibility of measuring end-expiratory resting level (thoracic gas volume; TGV), and hence lung volume in its close interrelationship to airway function (airway resistance; R(aw), its reciprocal value, airway conductance, Gaw). Therefore, this technique is a valuable aid for objective evaluation of lung diseases in infants. This article gives an overview of the physiological background of this particular measuring technique and its usefulness in the clinical routine. Plethysmographic data obtained in infant survivors of the infant respiratory distress syndrome (iRDS), in infants with cystic fibrosis (CF) and in the so-called 'wheezy infants' are presented. Special emphasis is given to the fact that in such infants the interrelationship between changes in end-expiratory resting level and the deficit in airway mechanics is of great importance and, consequently, for the determination of functional lung derangement in each particular case of lung disease, both TGV and the closely related R(aw) and Gaw have to be evaluated. This recommendation has to be kept in mind when the different diagnostic tools for evaluation of treatment facilities are applied in this particular young age group of patients with lung disease. In children as in adult patients, inhalative treatment must be considered the mainstay of all therapeutic measures. However, in infants, the efficacy of such treatment regimens must first be evaluated by adequate functional investigations. Infant whole-body plethysmography offers one such possibility.

Methods of assessment and findings regarding pulmonary function in infants less than 1000 grams.

Information regarding lung mechanics and pulmonary function may be used to influence the selection of tiny infant ventilator settings and thus minimize the risk for lung injury during mechanical ventilation. Data regarding compliance and resistance are presented in comparison to various ventilator settings.