Congenital diaphragmatic hernia repair on ECMO

Congenital diaphragmatic hernia (CDH) with severe respiratory failure in the first few hours of life continues to be associated with significant mortality. Extracorporeal membrane oxygenation (ECMO) has been successfully used postoperatively to reverse the effects of severe pulmonary hypertension. Since 1984, ECMO has been required in 27 of the patients we treated with CDH. This report describes our experience with six very high-risk patients placed on ECMO prior to the operation who subsequently underwent repair of their diaphragmatic hernias while on ECMO. Two patients presented in extremis, unlikely to survive initial operative repair, and were placed on ECMO prior to the operation. All six patients had immediate respiratory distress after birth with mean Apgars of 2.3 and 3.7. The best pre-ECMO arterial blood gas (postductal) showed mean ± SEM values of 6.97 ± 0.1; PO₂ = 54.8 ± 5.9; PCO₂ = 79.5 ± 16.9. Immediately prior to ECMO, the mean ± SEM ventilatory index (VI = rate × mean airway pressure) was 1,233 ± 44, with a mean pH of 7.17 ± 0.05; PO₂ = 32 ± 2.9; PCO₂ = 59 ± 5.3 and a mean AaDO₂ of 622 ± 4.8. The timing of the operative repair averaged 25 hours following initiation of ECMO. Three right-sided and three left-sided hernias were treated. Four were repaired through an abdominal approach, and two via thoracotomy; four required a Gortex patch closure. Postoperative bleeding was not a major problem in these heparinized patients. Four of these six patients survived, and follow-up of 2 months to 3 years shows no significant respiratory compromise. Based on this initial experience, we feel that repair of CDH can be done safely while the patient is on ECMO. This approach avoids perioperative barotrauma and protects the patient from the pulmonary function deterioration and worsening pulmonary hypertension that often is associated with operative repair. This option should be considered for high-risk patients with CDH who deteriorate during prolonged preoperative treatment and for those who present in extremis.