Drainage Fluid Biomarkers and Anastomotic Leakage in Colorectal Surgery. A Monocentric Prospective Observational Study

Anastomotic leakage (AL) is one of the most feared intra-abdominal septic complications (IASC) after colorectal surgery. It is defined as the leak of intestinal content due to an anastomotic dehiscence. Incidence ranges from 2% to 20%. AL is usually associated to systemic inflammatory response, even if in some cases the presentation may be subclinical. Therefore, AL is suspected in patients with a strong inflammatory response and can be confirmed by imaging with contrast enhanced computed tomography (CT) scan or water-soluble contrast studies. Nevertheless, imaging has varying sensitivity and specificity and is usually performed once the patient has a clinical evidence, thus potentially delaying the correct timing for surgery. Despite several studies about this topic and the plenty of known risk factors as mentioned above, AL is still not easy to predict. Different tools other than imaging have been studied in order to make diagnosis of AL at an early stage, as the measurement of some biomarkers of inflammation in serum and in drainage fluid.

Biomarkers as white cell blood count (WBC), C-reactive protein (CRP), cytokines (e.g. TNFa, IL-6, IL-1b), markers of ischemia (e.g. lactate) and procalcitonin (PCT) have been used for an early detection of AL and other intra-abdominal septic complications. The primary aim of our study was to assess the role of drainage fluid CRP and lactate-dehydrogenase (LDH) in the early detection of anastomotic leakage.