Detection of postoperative sepsis in infants with the use of metabolic stress monitoring.

OBJECTIVES: To evaluate the ability of serial protein metabolic monitoring to detect postoperative injury due to serious bacterial infection in infants by comparing changes observed in these protein parameters with more conventionally accepted indexes of infection.

DESIGN: Retrospective review of infants whose postoperative course was complicated by bacterial infection compared with a matched cohort of infants in whom bacterial infection did not develop postoperatively.

SETTING: Neonatal and pediatric intensive care units at the Wake Forest University Medical Center, Winston-Salem, NC.

PATIENTS: Critically ill infants (N = 40) recovering from major surgical intervention.

MAIN OUTCOME MEASURES: Serum C-reactive protein, prealbumin, and tumor necrosis factor concentrations were compared with the white blood cell count, immature-total neutrophil ratio, and body temperature obtained within 24 hours before and following the new onset of culture-established postoperative bacterial infection in 13 infants. These infants were compared with a matched cohort of 27 infants in whom postoperative bacterial infection did not develop.

RESULTS: Only C-reactive protein (P = .0001) and prealbumin (P = .0003) levels were significantly altered in association with the onset of serious bacterial infection (paired t test). The C-reactive protein levels were clearly superior to all other variables in predicting postoperative infection (at cutoff point > 6.0 mg/dL; sensitivity, 92%; specificity, 96%). The predictive power of prealbumin level was lower, but acceptable (at cutoff point < or = 9.0 mg/dL; sensitivity, 85%; specificity, 74%).

CONCLUSIONS: Monitoring of serial protein metabolic stress with C-reactive protein and prealbumin levels in infants following operations is more effective than the white blood cell count, immature-total neutrophil ratio, or temperature in detecting serious postoperative infections.