053 - Improved Outcomes After Implementation of a Physiologic Ventilator Strategy for Neonates with Congenital Diaphragmatic Hernia

Publication Number: 53.5107

Carly E. Byrd, Johns Hopkins Children's Center, Baltimore, MD, United States; Julie Nogee, Johns Hopkins University, Towson, MD, United States; Maureen M.. Gilmore, MD, Johns Hopkins University School of Medicine, Towson, MD, United States; Ahmet Baschat, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Amaris Keiser, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Jennifer M.. Organ, Johns Hopkins Children's Center, Nottingham, MD, United States; Shaun Kunisaki, Johns Hopkins Children's Center, Baltimore, MD, United States; Suneetha Desiraju, Johns Hopkins University School of Medicine, Baltimore, MD, United States

Background: Congenital diaphragmatic hernia (CDH) is a challenging, multifaceted disorder, complicated by concurrent fetal-to-neonatal transition. Our institution revised pre-operative management guidelines for these neonates, adopting a physiology-based approach supporting the known triad of lung hypoplasia, multifactorial pulmonary hypertension and cardiac dysfunction, by prioritizing gentle ventilation. We use a conventional ventilation in assist-control mode with low tidal volumes (4-5ml/kg), low PEEP (3-5 cmH2O), and low inspiratory time (0.3sec) with acceptance of permissive hypercapnia, based on preductal blood gases. This strategy differed from prior management that used higher mean airway pressures, causing hyperinflation, and monitored post ductal gases which underestimated gas exchange.

Objective: We compared outcomes in newborns with CDH prior to implementing these new guidelines (Epoch 1) to those treated post-guideline revision (Epoch 2). With unchanged thresholds for extracorporeal life support (ECLS), we hypothesized that our ventilation strategy would reduce ECLS cannulation rates and inhaled nitric oxide (iNO) use.

Design/Methods: This was a retrospective single-center study evaluating outcomes from 2016 to 2024. Non-parametric and parametric comparison of data were used as appropriate.

Results: Of 63 infants with CDH, 50 were born in Epoch 1 and 13 in Epoch 2 with comparable demographics. The two groups had similar hernia severity by observed to expected lung-to-head ratio, presence of liver herniation, hernia side, and history of fetal endoscopic tracheal occlusion (FETO) (Table 1). Results indicate a decrease in both ECLS cannulation from 46% to 8% (p=0.02) and use of iNO from 82% to 23% (p=0.001) (Figure 1). Time to repair was shorter in Epoch 2 (2 vs. 4 days, p=0.009). Of those extubated, ventilator days decreased from 22.5 to 7.5 days (p=0.004). There was a reduction in the number of pulmonary vasodilator medications required per patient between Epochs (3.0 vs 0.4, p< 0.001). (Table 2). There was a trend toward a decrease in mortality between groups (28% Epoch 1, 8% Epoch 2) and in length of level IV NICU stay of survivors from 52 to 37 days.

Conclusion(s): CDH is a challenging disease to manage during the critical time of fetal-to-neonatal transition. Implementation of a gentle, physiologic ventilation strategy has led to reduced ECLS cannulation rates, length of ventilation, iNO and other pulmonary vasodilator use. Mortality and length of level IV ICU stay were also impacted. Data collection and analysis is ongoing in Epoch 2.

Table 1: Demographics
Demographics of both Epochs

Figure 1
Significant decrease in ECLS and iNO use with new CDH guidelines

Table 2: Outcomes


Table 1: Demographics
Demographics of both Epochs

Figure 1
Significant decrease in ECLS and iNO use with new CDH guidelines

Table 2: Outcomes