Clinical utility or peri-operative C-reactive protein testing in general surgery

INTRODUCTION C-reactive protein (CRP) is an acute-phase protein used clinically to diagnose infectious and inflammatory disease and monitor response to treatment. CRP measurement in the peri-operative period was audited and patterns of change analysed for elective general surgical patients. PATIENTS AND METHODS General surgical patients (201) admitted for elective general surgery over a 3-month period were considered for the study. CRP results pre- and postoperatively were recorded, and data on co-morbid conditions and surgical procedure were noted. RESULTS CRP was requested pre-operatively on 84% of patients. A high CRP was more likely to be found in patients with co-morbidity. Postoperatively, CRP was requested during the first 3 days on 69% of patients. CRP peaked at postoperative days two or three, and then fell. In patients who had a high pre-operative CRP, the peak CRP was higher and occurred later, than those who had a normal pre-operative CRP. CONCLUSIONS CRP requesting pre-operatively is common, but is not recommended in NICE guidelines. Postoperatively, CRP levels rise; as a result, its use as a tool to screen for infection is limited. CRP has a role in diagnosis of infection after the first three postoperative days and in monitoring response to treatment. Therefore, routine use of CRP measurements pre-operatively and in the first 2 or 3 days post-operatively is not recommended. A peri-operative CRP should only be requested if there is a clear clinical indication.