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Extracorporeal membrane oxygenation (ECMO) has been used as a support system for neonates with pulmonary failure since 1975. During ECMO, thermal regulation, pulmonary gas exchange, and cardiac output can be partially or nearly completely provided by the circuit. The presumed resultant decrease in energy requirement has prompted the question of whether infants are in a catabolic or anabolic state of metabolism while on ECMO. Directly measuring the metabolic rate in babies on ECMO is difficult. However, studying the nitrogen balance in these infants may suggest an answer. Nitrogen balance was studied in 21 neonates spanning a single ECMO team's experience at two institutions. Children were studied at the Ochsner Clinic from 1986 to 1990 and at the University of Chicago Wyler Children's Hospital from 1990 to the present. The infants received total parenteral nutrition (TPN) as their only nutritional source during the entire ECMO course. During this time, 24-h urine collections were analyzed for urea nitrogen (UUN). The daily nitrogen balance was calculated by subtracting nitrogen output (estimated as the UUN) from nitrogen input (the measured amino acid content of the intravenous feeding). Fecal losses were not included in the nitrogen output since the infants were not enterally fed and rarely had stools while on ECMO. The kilojoules (1 kilocalorie = 4.2 kilojoules) and protein provided by the parenteral nutrition varied. Nitrogen intake exceeded nitrogen output by ECMO day 2 (the initial nitrogen balance determination). Infants receiving as little as 0.4 g/kg protein and 168 kJ/kg daily remained in positive nitrogen balance.

Thirty infants were diagnosed with extrahepatic biliary atresia (EBA) from July 1978 to July 1989; 28 have undergone a Kasai or Lilly-Altman modification of the Kasai portoenterostomy; 2 were excluded from surgery because they presented after 3 months of age and had advanced biliary cirrhosis. Immediate postoperative drainage (>30 ml/day was achieved in 24 patients (86%), with 14 (50%) surviving free of jaundice. The average follow-up was 2.25 years (range 3 months to 10 years); the longest survivor is 10.3 years old. The overall survival was 64%, and 5-year survival 50%. Of 24 infants operated on at

Posterolateral congenital diaphragmatic hernia (Bochdalek's hernia, CDH) that presents in the neonatal period is often manifest as life-threatening respiratory distress due to mechanical compression of the cardiopulmonary system by herniated viscera. Most patients can be supported through surgical reduction and repair with standard neonatal techniques. Postoperatively, many develop severe, refractory persistent pulmonary hypertension of the newborn (PPHN) after a variable period of adequate oxygenation. Despite aggressive ventilatory and pharmacologic maneuvers, a significant number of these infants develop fatal hypoxia and acidosis. At our institution, extracorporeal membrane oxygenation (ECMO) has been used as a therapy of last resort in 12 moribund infants with PPHN and respiratory failure after repair of CDH. There were 7 survivors. All long-term survivors [6] were totally weaned from ventilatory support; all met the criteria for nonsurvival as defined by Bohn et al. [2]. Eight patients (4 survivors) had no PaO2 greater than 100 torr postoperatively. ECMO can relieve the hypoxic and metabolic stimuli that aggravate pulmonary hypertension and provide cardiopulmonary support. It is the treatment of choice for infants who are deteriorating in the face of maximum conventional therapy after surgical correction. Lesions that were formerly denoted nonsurvivable can be effectively treated. It is urged that this therapy be used whenever necessary to sustain the life of an infant who has survived operation, regardless of whether the patient has demonstrated a “honeymoon” period, PaO2 greater than 100 torr, or any other factor conventionally thought to delineate survivable from nonsurvivable lesions. Such practices may exclude patients with survivable lesions from life-saving therapy.