Effects of Probiotics Supplementation on CRP, IL-6, and Length of ICU Stay in Traumatic Brain Injuries and Multiple Trauma Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

METHOD: This meta-analysis aims to evaluate the effectiveness of probiotics in reducing inflammatory biomarkers and the length of intensive care unit (ICU) stays. PubMed-Medline, SCOPUS, Embase, and Google Scholar databases up to July 2021 were searched. The meta-analysis was carried out using random-effect analysis. To determine the sources of heterogeneity, subgroup analyses were performed. In case of the presence of publication bias, trim and fill analysis was carried out. The Cochrane Collaboration tool was used for checking the quality assessment. We hypothesized that probiotics would improve inflammatory markers (CRP and IL-6) and the length of ICU stay in traumatic brain injury and multiple trauma patients. RESULTS: The present meta-analysis, which includes a total of seven studies, showed that there were no significant effects of probiotics supplementation on interleukin (IL)-6 (Hedges's g = −2.46 pg/ml; 95% CI: −12.16, 7.25; P=0.39), C-reactive protein (CRP) (Hedges's g = −1.10 mg/L; 95% CI: −2.27, 0.06; P=0.06), and the length of staying in ICU. The overall number of RCTs included in the analysis and the total sample size were insufficient to make firm conclusions. CONCLUSION: As a result, more carefully designed RCTs are needed to investigate the effect of probiotics on inflammatory biomarkers and the length of ICU stay in traumatic brain injuries and multiple trauma patients in greater detail.