Kinetics of procalcitonin and C-reactive protein and the relationship to postoperative infection in young infants undergoing cardiovascular surgery

BACKGROUND: The utility of procalcitonin and C-reactive protein (CRP) as infectious biomarkers following infant cardiothoracic surgery is not well defined. METHODS: We designed a prospective cohort study to evaluate procalcitonin and CRP after infant cardiothoracic surgery. Procalcitonin and CRP were drawn pre-operatively and 24/72 hours post-operation or daily in delayed sternal closure patients. Presence of infection within 10 days of surgery, vasoactive-inotropic scores at 24 and 72 hours, and length of intubation, intensive care unit stay, and hospital stay were documented. RESULTS: Procalcitonin and CRP were elevated at 24 hours. Procalcitonin then decreased while CRP increased in patients undergoing delayed sternal closure or cardiopulmonary bypass. In the delayed sternal closure group, procalcitonin was significantly higher on post-operative days 2–5 in patients who ultimately developed infection. Higher procalcitonin was independently associated with increased vasoactive-inotropic score at 72 hours. CRP did not correlate with infection or post-operative support. CONCLUSIONS: Procalcitonin rises after cardiothoracic surgery in infants but decreases by 72 hours while CRP remains elevated. Sternal closure may affect CRP but not procalcitonin. Procalcitonin is independently associated with circulatory support requirements at 72 hours post-operation and development of infection. Procalcitonin may have greater utility as a biomarker in this population.