To investigate the therapeutic effect of vasopressin on vasodilatory shock in patients after cardiac surgery.

All randomized controlled clinical trials (RCTs) of vasopressin in the treatment of vasodilatory shock patients from January 1980 to December 2018 were retrieved from CNKI, Wanfang, PubMed, Embase, Springer Link, Cochrane Library, etc. The primary outcome measure was mortality rate, and secondary outcome indicators were length of stay in intensive care unit (ICU), mean arterial pressure (MAP), and incidence of serious adverse events and atrial fibrillation. Literature screening, data extraction, and quality evaluation were conducted by two researchers independently. Meta-analysis was performed with RevMan 5.3 software. Funnel plot was used to analyze the publication bias.

A total of 458 related articles were retrieved. According to the inclusion and exclusion criteria, four RCT studies were finally included, with a total of 458 patients. One study was considered to have a lower risk of bias and three had a moderate risk of bias. The meta-analysis showed that vasopressin did not significantly improve the mortality of vasodilatory shock patients after cardiac surgery (odds ratio [OR]=0.95, 95% confidence interval [CI]: 0.55-1.64, P=0.85) and length of stay in ICU (mean difference [MD]=-0.41, 95%CI: -1.40-0.57, P=0.41) compared with the control group, improved the patient's MAP (MD=7.77, 95%CI: 2.59-12.94, P=0.003), and did not increase the incidence of severe adverse events (OR=0.89, 95%CI: 49-1.60, P=0.69). Although vasopressin had a tendency to decrease the incidence of atrial fibrillation, there was no statistical difference (OR=0.19, 95%CI: 0.03-1.04, P=0.06).

The available evidence suggests that vasopressin could not significantly improve mortality and the length of stay in ICU in patients with vasodilator shock after cardiac surgery, but it may improve MAP and reduce the incidence of atrial fibrillation.