High-frequency oscillatory ventilation versus conventional ventilation in the respiratory management of term neonates with a congenital diaphragmatic hernia: a retrospective cohort study

Association between initial ventilation mode and hospital outcomes for severe congenital diaphragmatic hernia

OBJECTIVE

To determine the association between initial delivery room (DR) ventilator (conventional mechanical ventilation [CMV] versus high frequency oscillatory ventilation [HFOV] and hospital outcomes for infants with severe congenital diaphragmatic hernia (CDH).

STUDY DESIGN

Quasi-experimental design before/after introducing a clinical protocol promoting HFOV. The primary outcome was first blood gas parameters. Secondary outcomes included serial blood gas assessments, ECMO, survival, duration of ventilation, and length of hospitalization.

RESULTS

First pH and CO2 were more favorable in the HFOV group (n = 75) than CMV group (n = 85), median (interquartile range (IQR)) pH 7.18 (7.03, 7.24) vs. 7.05 (6.93, 7.17), adjusted p-value < 0.001; median CO2 62.0 (46.0, 82.0) vs 85.9 (59.0, 103.0), adjusted p-value < 0.001. ECMO, survival, duration of ventilation, and length of hospitalization did not differ between groups in adjusted analysis.

CONCLUSION

Among infants with severe CDH, initial DR HFOV was associated with improved early gas exchange with no adverse differences in hospital outcomes.

Predictors of Mortality in Very Low Birth Weight Neonates With Congenital Diaphragmatic Hernia

BACKGROUND

Limited data exists regarding the mortality of very low birth weight (VLBW) neonates with congenital diaphragmatic hernia (CDH). This study aims to quantify and determine predictors of mortality in VLBW neonates with CDH.

METHODS

This analysis of 829 U.S. NICUs included VLBW [birth weight ≤1500g] neonates, born 2011-2021 with and without CDH. The primary outcome was in-hospital mortality. A generalized estimating equation regression model determined the adjusted risk ratio (ARR) of mortality.

RESULTS

Of 426,140 VLBW neonates, 535 had CDH. In neonates with CDH, 48.4% had an additional congenital anomaly vs 5.5% without. In-hospital mortality for neonates with CDH was 70.4% vs 12.6% without. Of those with CDH, 73.3% died by day of life 3. Of VLBW neonates with CDH, 38% were repaired. A subgroup analysis was performed on 60% of VLBW neonates who underwent delivery room intubation or mechanical ventilation, as an indicator of active treatment. Mortality in this group was 62.7% for neonates with CDH vs 16.4% without. Higher Apgars at 1 min and repair of CDH were associated with lower mortality (ARR 0.91; 95%CI 0.87,0.96 and ARR 0.28; 0.21,0.39). The presence of additional congenital anomalies was associated with higher mortality (ARR 1.14; 1.01,1.30).

CONCLUSION

These benchmark data reveal that VLBW neonates with CDH have an extremely high mortality. Almost half of the cohort have an additional congenital anomaly which significantly increases the risk of death. This study may be utilized by providers and families to better understand the guarded prognosis of VLBW neonates with CDH.

TYPE OF STUDY

Level II.

LEVEL OF EVIDENCE

Level II.

The role of extracorporeal life support and timing of repair in infants with congenital diaphragmatic hernia

Extracorporeal life support (ECLS) serves as a rescue therapy for patients with congenital diaphragmatic hernia (CDH) and severe cardiopulmonary failure, and only half of these patients survive to discharge. This costly intervention has a significant complication risk and is reserved for patients with the most severe disease physiology refractory to maximal cardiopulmonary support. Some contraindications to ECLS do exist such as coagulopathy, lethal chromosomal or congenital anomaly, very preterm birth, or very low birth weight, but many of these limits are being evaluated through further research. Consensus guidelines from the past decade vary in recommendations for ECLS use in patients with CDH but this therapy appears to have a survival benefit in the most severe subset of patients. Improved outcomes have been observed for patients treated at high-volume centers. This review details the evolving literature surrounding management paradigms for timing of CDH repair for patients receiving preoperative ECLS. Most recent data support early repair following cannulation to avoid non-repair which is uniformly fatal in this population. Longer ECLS runs are associated with decreased survival, and patient physiology should guide ECLS weaning and eventual decannulation rather than limiting patients to arbitrary run lengths. Standardization of care across centers is a major focus to limit unnecessary costs and improve short-term and long-term outcomes for these complex patients.

Mechanical ventilation in special populations

Optimal respiratory support can only be achieved if the ventilator strategy utilized for each individual patient at any given point in the evolution of their disease process is tailored to the underlying pathophysiology. The critically ill newborn infant requires individualized patient care when it comes to mechanical ventilation. This can only occur if the clinician has a good understanding of the different pathophysiologies of a variety of conditions that can lead to respiratory failure. In this chapter we describe the key pathophysiological features of bronchopulmonary dysplasia, meconium aspiration syndrome and lung hypoplasia syndromes with emphasis on congenital diaphragmatic hernia. We review available evidence to guide management an provide specific recommendations for pathophysiologically-based mechanical ventilation support.

Congenital diaphragmatic hernia: quality improvement using a maximal lung protection strategy and early surgery-improved survival

To evaluate the effectiveness of a novel protocol, adopted in our institution, as a quality improvement project for congenital diaphragmatic hernia (CDH). A maximal lung protection (MLP) protocol was implemented in 2019. This strategy included immediate use of high-frequency oscillatory ventilation (HFOV) after birth, during the stay at the Neonatal Intensive Care Unit (NICU), and during surgical repair. HFOV strategy included low distending pressures and higher frequencies (15 Hz) with subsequent lower tidal volumes. Surgical repair was performed early, within 24 h of birth, if possible. A retrospective study of all inborn neonates prenatally diagnosed with CDH and without major associated anomalies was performed at the NICU of Schneider Children's Medical Center of Israel between 2009 and 2022. Survival rates and pulmonary outcomes of neonates managed with MLP were compared to the historical standard care cohort. Thirty-three neonates were managed with the MLP protocol vs. 39 neonates that were not. Major adverse outcomes decreased including death rate from 46 to 18% (p = 0.012), extracorporeal membrane oxygenation from 39 to 0% (p < 0.001), and pneumothorax from 18 to 0% (p = 0.013).

CONCLUSION

 MLP with early surgery significantly improved survival and additional adverse outcomes of neonates with CDH. Prospective randomized studies are necessary to confirm the findings of the current study.

WHAT IS KNOWN

• Ventilator-induced lung injury was reported as the main cause of mortality in neonates with congenital diaphragmatic hernia (CDH). • Conventional ventilation is recommended by the European CDH consortium as the first-line ventilation modality; timing of surgery is controversial.

WHAT IS NEW

• A maximal lung protection strategy based on 15-Hz high-frequency oscillatory ventilation with low distending pressures as initial modality and early surgery significantly reduced mortality and other outcomes.

Do FETO CDH survivors need the same follow-up program as non-FETO patients?

Congenital diaphragmatic hernia (CDH) survivors are at risk of developing significant chronic health conditions and disabilities. The main purpose of this study was to compare the outcomes of CDH infants at 2 years of age (2y) according to whether the infants had undergone fetoscopic tracheal occlusion (FETO) during the prenatal period and characterize the relationship between morbidity at 2y and perinatal characteristics. Retrospective cohort single center study. Eleven years of clinical follow-up data (from 2006 to 2017) were collected. Prenatal and neonatal factors as well as growth, respiratory, and neurological evaluations at 2y were analyzed. One hundred and fourteen CDH survivors were evaluated. Failure to thrive (FTT) was present in 24.6% of patients, gastroesophageal reflux disease (GERD) in 22.8%, 28.9% developed respiratory problems, and 22% had neurodevelopment disabilities. Prematurity and birth weight < 2500 g were related to FTT and respiratory morbidity. Time to reach full enteral nutrition and prenatal severity markers seemed to influence all outcomes, but FETO therapy itself only had an effect on respiratory morbidity. Some variables related to postnatal severity (ECMO, patch closure, days on mechanic ventilation, and vasodilator treatment) were associated with almost all outcomes.  Conclusion: CDH patients have specific morbidities at 2y, most of them related to lung hypoplasia severity. Only respiratory problems were related to FETO therapy itself. The implementation of a specific multidisciplinary follow-up program for CDH patients is essential to provide them the best standard of care, but, more severe patients, regardless of whether they received prenatal therapy, need a more intensive follow-up. What is Known: • Antenatal fetoscopic endoluminal tracheal occlusion (FETO) increases survival in more severe congenital diaphragmatic hernia patients. • Congenital diaphragmatic hernia survivors are at risk of developing significant chronic health conditions and disabilities. Very limited data are available about the follow-up in patients with congenital diaphragmatic hernia and FETO therapy. What is New: • CDH patients have specific morbidities at 2 years of age, most of them related to lung hypoplasia severity. • FETO patients present more respiratory problems at 2 years of age but they don't have an increased incidence of other morbidities. More severe patients, regardless of whether they received prenatal therapy, need a more intensive follow-up.

Exploration of the thoracoscopic treatment of esophageal atresia under high-frequency ventilation

Objective

Explore the feasibility and safety of thoracoscopy in the treatment of esophageal atresia under high-frequency oscillatory ventilation (HFOV) mode.

Methods

This was a single-center retrospective analysis. A total of 24 children were divided into the HFOV and the No-HFOV group. The demographic information, surgical results and relevant experience were analyzed.

Results

All patients in the HFOV group underwent thoracoscopic esophageal atreplasty with a mean operation duration of 165.8 ± 33.9 min. Two patients had postoperative anastomotic leakage, which was cured after conservative treatment. One child had a recurrent tracheoesophageal fistula, which was closed after endoscopic cauterization. The mean postoperative mechanical ventilation time was 8.83 ± 8.02 days. There was no return of anastomotic leakage or r-TEF after oral feeding. Furthermore, there was no significant difference between the NO-HFOV and the HFOV groups except for the operation time where the HFOV group was shorter than that of the NO-HFOV group.

Conclusion

Thoracoscopic esophageal atresia anastomosis under HFOV ventilation is feasible for patients with severe pulmonary infection, heart malformation, such as patent ductus arteriosus, ventricular septal defect, and poor anesthesia tolerance, but the long-term prognosis still needs further study in a large sample size.