Effect of preextracorporeal membrane oxygenation ventilation days and age on extracorporeal membrane oxygenation survival in critically ill children.

PURPOSE

The aim of the study is to test the effect of age and preextracorporeal membrane oxygenation (pre-ECMO) days of ventilation on ECMO survival in the pediatric population.

METHODS

Retrospective analysis of noncardiac, pediatric (age >30 days) ECMO patients for the period January 1984 to June 2006. Pre-ECMO demographic, ventilatory, and lung injury severity variables were modeled with stepwise logistic regression to estimate survival probabilities associated with pre-ECMO ventilation duration and patient age. Patients were excluded from review for the following: pre-ECMO cardiac arrest, pre-ECMO ventilation of more than 30 days (chronic), or multiple runs on ECMO.

RESULTS

For the period of review, 2550 patients met inclusion/exclusion criteria. The population had a mean age of 3.6 +/- 5.1 years (median age, 1 year). The mean pre-ECMO days of ventilation were 5.2 +/- 4.9 (median, 4 days). The overall survival probability was 58.6%. The mean oxygen index and Pao(2)/Fio(2) ratio were 62.2 +/- 48.2 and 95.5 +/- 48.2, respectively. The population overall demonstrated a statistically significant, exponential decline in survival as pre-ECMO days of ventilation increased (P < .05). For each additional year of age, survival decreased by an average of 2.5%. For each additional day of pre-ECMO ventilation, survival decreased by an average of 2.9%. Younger ages were generally associated with higher survival probabilities at each ventilation day.

CONCLUSIONS

In the pediatric population, survival decreases significantly as pre-ECMO ventilator days increase. Survival is also inversely related to patient age. Thus, patient age and duration of ventilation should be considered when evaluating suitability for ECMO.