Predictive value of perioperative procalcitonin, C reactive protein and high-sensitivity C reactive protein for the risk of postoperative complications after non-cardiac surgery in elderly patients: a nested case–control study

OBJECTIVE: Little is known about the correlation between perioperative concentrations of inflammatory biomarkers and postoperative complications. This study explored whether the plasma concentrations and perioperative changes of procalcitonin (PCT), C reactive protein (CRP) and high-sensitivity CRP (hsCRP) could predict the risk of postoperative morbidity in elderly patients undergoing elective non-cardiac surgery. DESIGN: A nested case–control study. SETTING: A tertiary hospital in China. PARTICIPANTS: A total of 498 patients aged ≥65 years from a prospective cohort who underwent elective non-cardiac surgery between June 2020 and April 2021. PRIMARY OUTCOME MEASURES: The primary outcomes were the efficacy of plasma concentrations of PCT, CRP and hsCRP in predicting the risk of Clavien-Dindo Classification (CDC) ≥grade 3 and major complications. The major complications included mortality, an intensive care unit stay length >24 hour, cardiovascular events, acute kidney injury, postoperative cognitive dysfunction and infections. RESULTS: For major complications, the area under the curve (AUC) (95% CI) of PCT-24 hours, PCT change and PCT change rate were 0.750 (0.698 to 0.803), 0.740 (0.686 to 0.795) and 0.711 (0.651 to 0.771), respectively. The AUC (95% CI) of CRP-24 hours, CRP change, CRP change rate and hsCRP baseline were 0.835 (0.789 to 0.881), 0.818 (0.770 to 0.867), 0.691 (0.625 to 0.756) and 0.616 (0.554 to 0.678), respectively. For complications ≥CDC grade 3, the AUC (95% CI) of PCT-24 hours, PCT change and PCT change rate were 0.662 (0.543 to 0.780), 0.643 (0.514 to 0.772) and 0.627 (0.494 to 0.761), respectively. The AUC (95% CI) of CRP-24 hours and hsCRP baseline were 0.649 (0.527 to 0.771) and 0.639 (0.530 to 0.748), respectively. CONCLUSIONS: PCT-24 hours, CRP-24 hours, the change of perioperative PCT and CRP were valuable predictors of major complications occurring within 30 days after non-cardiac surgery in the elderly. TRIAL REGISTRATION NUMBER: China Clinical Trial Registry: ChiCTR1900026223.