Application of controlled low central venous pressure during hepatectomy: A systematic review and meta-analysis.

Study Objective: Previous studies reported that controlled low central venous pressure (CVP) can reduce blood loss during liver resection. This systematic review and meta-analysis sought to explore the efficacy and safety of low CVP in patients undergoing hepatectomy.

Design: A systematic review and meta-analysis of randomized controlled trials (RCTs).

Review Methods: RCTs were searched in PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Chinese BioMedical database, Chinese Scientific Journals Database, and Wanfang database from inception to April 30, 2021. Subgroup analyses were performed based on different surgical methods (open hepatectomy vs laparoscopic hepatectomy) and published countries (China vs other countries). The quality of evidence was assessed by Grading of Recommendations, Assessment, Development, and Evaluation.

Main Results: Eighteen RCTs containing 1285 participants (626 patients in the low CVP group and 659 patients in the control group) were included in this study. The forest plot showed that low CVP effectively reduced blood loss during liver resection compared with the control group (MD = -311.92 mL, 95% CI [-429.03, -194.81]; P < 0.001, I = 96%). Furthermore, blood transfusion volume (MD = -158.85 mL, 95% CI [-218.30, -99.40]; P < 0.001, I = 55%) and the number of patients requiring transfusion (RR 0.41, 95% CI 0.27-0.65, P < 0.001, I = 0%) were decreased in the low CVP group. Subgroup analyses showed similar results. Notably, the alanine transaminase level was significantly lower in the low CVP group during the first five postoperative days. However, no significant differences were observed for other postoperative liver function indicators (aspartate aminotransferase, total bilirubin, serum albumin, and prothrombin time), renal function indicators (blood urea nitrogen and serum creatinine) and perfusion parameters (heart rate, mean arterial pressure, and urine volume). The incidence of complications was similar between the two groups.

Conclusion: The findings of this study showed that low CVP is effective and safe during hepatectomy. Therefore, this technique is recommended to reduce blood loss during hepatectomy. PROSPERO registration number: CRD42021232829.