The Early Diagnostic Value of Procalcitonin in Pneumonia After Off-Pump Coronary Artery Bypass Grafting Surgery

BACKGROUND The incidence of early postoperative pneumonia (EPOP) after off-pump coronary artery bypass grafting surgery (CABG) is relatively high, but its diagnosis by traditional methods remains difficult, which could be deleterious to the prognosis. Moreover, few data exist regarding procalcitonin (PCT) in early diagnosis of pneumonia after off-pump CABG. Thus, this study was performed to evaluate the value of PCT in diagnosing EPOP after off-pump CABG. MATERIAL AND METHODS A total of 402 consecutive patients undergoing off-pump CABG were retrospectively enrolled. Forty-four patients were diagnosed with EPOP and 112 patients were diagnosed with systemic inflammatory response syndrome (SIRS). Chest roentgenogram, serum PCT, white blood cells, neutral granulocyte ratio, and daily maximum body temperature were recorded. The ability of PCT to diagnose EPOP was evaluated by receiver operating characteristic (ROC) analyses in comparison with traditional methods. Clinical net benefits were estimated via decision curve analysis (DCA). RESULTS PCT presented satisfying accuracy in diagnosing EPOP with a cutoff value of 1.585 ng/mL (area under the curve [AUC] 0.808, 95% confidence interval [CI] 0.724-0.891, sensitivity 73%, specificity 86%). PCT performed better in diagnosing EPOP among SIRS patients (AUC 0.868, 95% CI 0.748-0.988, sensitivity 85%, specificity 89%). DCA showed valuable clinical net benefits of PCT in diagnosing EPOP after off-pump CABG regardless of threshold selected. CONCLUSIONS PCT could be a diagnostic marker for EPOP after off-pump CABG. The optimal cutoff value for diagnosing EPOP was 1.585 ng/mL. The application of PCT in diagnosing EPOP in SIRS patients was also satisfying with a cutoff value of 1.775 ng/mL.