Hidden mortality rate associated with extracorporeal membrane oxygenation.

We reviewed the outcome of all infants referred to, and accepted in, our extracorporeal membrane oxygenation (ECMO) program during a 52-month period. One hundred sixty-seven referrals, representing 158 infants and nine mothers who had not yet delivered their infants, were accepted. Eighteen infants (11.3% of all neonates transported) died before leaving the referring hospital, during transport, or shortly after admission to our unit. Contraindications to ECMO excluded 17 (10.1%) of the 167 referrals. Sixty-two infants (37.1%) initially did not meet ECMO criteria. Two died before ECMO could be started. Sixty-eight infants (40.7%) were given ECMO therapy, and 11 died (16.1%). Nine mothers were referred because of fetal conditions that might require ECMO; of these infants, two died during delivery and three had contraindications to the use of ECMO. The four remaining infants were given ECMO therapy; three survived. The overall mortality rate was 27.5% (46/167); 18 (39.1%) of the 46 deaths were associated with transfer. The mortality rate associated with congenital diaphragmatic hernia was 63.6%. We recommend early transport of infants with this type of hernia during the postoperative "honeymoon" or during in utero transport with delivery at an ECMO center. We also recommend that infants with meconium aspiration syndrome be transported to an ECMO center when an oxygenation index of 25 is reached. The mortality rate associated with transport needs to be considered in evaluating ECMO programs. Earlier, expedited transfers may increase the survival rate.