COMPLICATIONS OF NEONATAL EXTRACORPOREAL MEMBRANE-OXYGENATION - COLLECTIVE EXPERIENCE FROM THE EXTRACORPOREAL LIFE-SUPPORT ORGANIZATION

Since 1973, 7667 neonates have been treated with extracorporeal membra ne oxygenation for severe respiratory failure and their cases reported to the Extracorporeal Life Support Organization Registry. The overall survival was 81% in these neonates, who were thought to have a surviv al of 20% without extracorporeal membrane oxygenation. A total of 4322 mechanical complications (0.56 +/- 0.84 per case) and 13,827 patient complications (1.80 +/- 2.12 per case) were reported overall. The most common mechanical complications included clots in the circuit (19%), cannula placement (9%), oxygenator failure (4%), and others (9%). Comm on patient complications included cardiopulmonary (43%), neurologic (3 5%), bleeding (35%), metabolic (32%), renal (25%), and infectious (9%) . From the initial experience to 1988 the average number of mechanical complications per case was 0.27 per case and this significantly incre ased during 1990 to 1992 to 0.75 per case (p < 0.05). Likewise, from 1 973-1985 to 1988 the average patient complications per case were 1.44 per case and this significantly increased during 1990 to 1992 to 2.10 per case. During the same periods, patient survival significantly decr eased from 84% (1973-1985 to 1988, n = 2463) to 80% (1990 to 1992, n = 4005). Venovenous double-lumen single cannula extracorporeal membrane oxygenation had a higher survival than venoarterial extracorporeal me mbrane oxygenation (91% versus 81%) and a lo,ver rate of major neurolo gic complications. The incidence and survival with seizures (6% and 89 % venovenous versus 13% and 61% venoarterial) or cerebral infarction ( 9% and 69% venovenous versus 14% and 46% venoarterial) was significant ly lower with the venovenous method and appeared to have a substantial impact on overall survival. The correlation of patient complication r ate and total complication rate with survival was highly significant, however, causality cannot be established. Explanations for the increas e in complications, relative to a decrease in survival despite a growi ng nationwide experience include (1) increased complexity of cases as many programs expand entry criteria (more premature infants, infants w ith grade 1 or 2 intracranial hemorrhage, and complex congenital diaph ragmatic hernia), (2) a sowing number of programs with fewer cases per program, Set seater accessibility, (3) less reluctance to report comp lications encountered during extracorporeal membrane oxygenation as gr oup experience grows, and (4) changes in the Extracorporeal Life Suppo rt Organization data form to be more inclusive of more minor complicat ions.