Association between timing of angiotensin II administration and outcomes in vasoplegia after cardiac surgery

Abstract

Objective

Vasoplegic shock after cardiopulmonary bypass (CPB) is a highly morbid condition. The novel vasopressor angiotensin II is increasingly being used for catecholamine-resistant vasoplegia. Although early intervention with adjunctive therapies such as methylene blue can improve outcomes of vasoplegia, the optimal timing for escalation with angiotensin II is unknown.

Methods

Pharmacologic data were extracted from electronic health records for patients who underwent surgery with CPB during 2017-2022. Patients were identified who received angiotensin II intraoperatively or postoperatively (ie, early or late). Multivariable logistic regression was used to determine the risk-adjusted effects of earlier angiotensin II administration on postoperative major adverse events: mortality and major morbidity.

Results

Seventy (1.4%) patients received angiotensin II for vasoplegia. The median [interquartile range] vasopressor dose at time of angiotensin II initiation was 0.33 [0.26-0.48] norepinephrine equivalents. Vasoplegia requiring treatment with angiotensin II was associated with substantial mortality (42.9% vs 3.3%, P < .001) and major morbidity (81.4% vs 20.3%, P < .001). The 51.4% of patients who began receiving angiotensin II intraoperatively had less major morbidity (94.1% vs 69.4%, P = .019) and a trend toward lower mortality (30.6% vs 55.9%, P = .057) than patients who received it postoperatively. In multivariable logistic regression, intraoperative initiation was an independent predictor of fewer major adverse events (odds ratio, 0.037; 95% confidence interval, 0.004-0.393).

Conclusions

Morbidity and mortality rates are high in patients given angiotensin II for vasoplegia. Initiating this medication intraoperatively may improve outcomes, underscoring the importance of early intervention for patients at risk for vasoplegia after CPB.