A systematic review on biomarkers implemented to measure surgical stress response in patients undergoing colorectal surgery.

Background: Measuring the surgical stress response (SSR) involves assessing physiological and biochemical markers that indicate the extent of the body's reaction to surgical trauma. The study aims to evaluate biomarkers used to measure (SSR) and to explore their potential clinical applicability. Mapping the existing literature may help address current limitations and inspire the development of new methods for measurement of SSR to measure SSR.

Methods: This systematic review was conducted per the Cochrane Handbook for Reviews of Interventions and reported following PRISMA guidelines. The research question was: What biomarkers are used to measure SSR in colorectal surgery, and is their benefit justified? A systematic literature search querying seven electronic databases (MEDLINE, Embase, Scopus, The Cochrane Database of Systematic Reviews, ScienceDirect Virtual Health Library, Google Scholar and Copenhagen University Library database) in addition one register (ClinicalTrials.gov) was conducted. The quality of bias control in the studies was assessed by 2 authors independent of each other using MINORS for non-randomized surgical studies and Cochrane risk-of-bias tool for randomized trials.

Results: Forty-nine studies met the inclusion criteria, encompassing 9,108 patients, mostly undergoing elective colorectal surgeries. The studies were categorized into four groups according to the aim of measuring SSR. The sample size in the included studies ranged from 14 to 1474. C-reactive protein was the most frequently assessed biomarker. Variations in sampling time points across studies made comparisons challenging. Many studies did not adjust for confounders or differentiate surgical contexts, raising concerns about their conclusions. There was a high heterogeneity in interventions, timing, and confounding adjustments.

Conclusion: Various biomarkers have been employed to measure SSR, with C-reactive protein being the most common. However, methodological heterogeneity hinders direct comparisons.

Trial registration: International Prospective Register of Systematic Reviews with reference (ID 515700).