Introduction: Patients on extracorporeal life support (ECLS) are felt to be at an increased risk of sepsis due to the suppression of their immune system. Due to this increased risk, a daily blood culture from the circuit has been recommended for infection surveillance while patients are requiring ECLS.

Methods: Data were obtained from ELSO registry forms and hospital charts of neonatal patients who underwent ECLS between January 1989 and July 1996 at Kosair Children's Hospital.

Results: There were 1152 blood cultures drawn on 183 patients(6.3 cultures/pt). Positive culture reports were noted in six of the 183 patients (3.3%) and seven of the 1152 cultures (0.6%). Pre-ECLS diagnoses of patients who developed sepsis during support included GBS sepsis (2), HSV sepsis (1), CHD (2), and PPHN (1). The median time on ECLS to the positive culture was 365 hours with a range of 246 to 446 hours. There were four coagulase negative staphylococcal infections, one S. aureus infection, and one E. coli infection. Four of these six patients had a positive endotracheal aspirate for the same organism prior to the positive culture. Five of the six patients had at least one chest tube in place during their ECLS course. The only significant differences noted between patients who developed sepsis while on ECLS and those who did not were the time spent on ECLS - 426 vs. 109 hours (p<0.0001), number of UAC days - 14 vs. 6(p<0.05), and number of chest tube days - 18 vs. 1 (p<0.05). Of the 27 patients who required ECLS for more than 10 days, six developed positive blood cultures (22%).

Conclusions: Despite the various reasons for an increased risk of sepsis while on ECLS, the occurence is relatively low. Patients at the highest risk for developing positive blood cultures while on ECLS are those who require more than 10 days of by-pass or have prolonged UACs or chest tubes in place. We conclude that daily surveillance blood cultures are unnecessary during the first 10 days of ECLS because of the low yield, with a projected savings of approximately $500 per ECLS patient.