Serial perfusion study depicts pulmonary vascular growth in the survivors of non-extracorporeal membrane oxygenation-treated congenital diaphragmatic hernia

Abstract

Background: Pulmonary growth in the survivors of congenital diaphragmatic hernia (CDH) still remains an intriguing issue. In the literature there are conflicting reports on pulmonary vascular growth in CDH.

Objective: In a cohort of CDH patients treated without extracorporeal membrane oxygenation (ECMO), serial perfusion studies were conducted prospectively to follow the growth of pulmonary vasculature.

Material and methods: Survivors of CDH repair between January 2000 and January 2003 were studied prospectively. Patient demography, time of presentation, arterioalveolar oxygen gradient (A-aDO(2)), time to complete lung expansion, and respiratory symptoms were noted. Lung perfusion studies were done at 3 months, 9 months, and 6 years of follow-up.

Results: 24 neonates completed the study. Mean presentation was 6.9 h, and preoperative A-aDO(2) was 288.8. 16/24 were managed by conventional ventilation and 8/24 required high-frequency ventilation and nitric oxide therapy (none were treated with ECMO). Mean duration of preoperative stabilization was 26.5 h, time to full lung expansion was 2.8 days, and postoperative ventilation was 3.7 days. Mean perfusion (%) of ipsilateral lung was 33.7% at 3 months, 43.2% at 9 months, and 46.8% at 6 years. Perfusion of ipsilateral lung improved by 9.4% from 3 to 9 months (p < 0.001), 13.1% from 3 months to 6 years (p < 0.001), and 3.7% from 9 months to 6 years postoperatively (p < 0.001). Respiratory symptoms were seen in 45% (11/24) of survivors at 3 months, 14% (4/24) at 9 months, and 12.5% (3/24) at 6 years postoperatively.

Conclusions: There was reduced perfusion of affected lung at 3 months which improved significantly at 9 months and at 6 years. Recovery of pulmonary vascular function correlated with amelioration of respiratory symptoms. The majority of survivors showing a significant vascular growth lead a symptom-free life.