An overview of reviews of Angiotensin II in distributive shock

High-dose catecholamine use in distributive shock is associated with high mortality. Angiotensin II (ATII) has demonstrated benefits in distributive shock patients, yet limited and inconsistent clinical data precludes its publication in treatment guidelines. This overview of reviews aims to critically assess and summarize systematic reviews on ATII benefits in distributive shock, identify knowledge gaps, and provide recommendations for future research. A systematic literature search for systematic reviews on the topic from 2020 was conducted, including PubMed, Embase, CINAHL, Epistemonikos, Scopus, PROSPERO, and Cochrane, and gray literature. Reviews were assessed by the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) checklist. Certainty of evidence was calculated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool. Both qualitative and quantitative data were summarized. The literature search yielded 239 results, resulting in 6 systematic reviews being included. The methodological quality was mostly low. ATII administration was associated with a decrease in background vasopressor requirements. Occurrence of serious adverse reactions were not found to be statistically significant. Mortality benefits was found in certain patient sub-groups but cannot be generalized. A consistent finding was that ATII improved MAP > 10 mmHg from baseline. ATII appears to be a safe and effective vasopressor in distributive shock management. The physiological and logistical benefits should be considered early in distributive shock management. This overview of reviews has identified certain gaps in the definition of catecholamine-resistant shock, ATII initiation thresholds, biomarker guided treatment, and occurrence of hemodynamic relapse which may guide future aspiring clinical trials.