Date of Award

January 2015

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Ala S. Haddadin

Second Advisor

Abbel A. Mangi

Subject Area(s)



Vasoplegia represents the constellation of hypotension, vasodilation, and elevated cardiac output - most often described around the context of cardiac surgery. This manuscript aims to universally define vasoplegia and examine risk factors and outcomes in an open-heart surgery patient population. We retrospectively obtained information on a population of patients who had undergone open-heart surgery between 2009 and 2011. Data were available for a total of 1992 patients. We propose a standard definition moving forward: vasoplegia is MAP< 60 mmHg, CI >2.4 L/min/m2, SVR <800 dyn·s·cm−5, and the requirement of concurrent vasopressors. The incidence of vasoplegia is 17.2% in our study population. Of those, 66.6% experienced mild, 24.8% experienced moderate, and 8.7% experienced severe vasoplegia. Beta-blockers were found protective of vasoplegia development. Factors that increase the risk of vasoplegia include increasing age, mitral valve replacement, myocardial infarction, atrial fibrillation, cardiopulmonary bypass, and others. A novel Vasoplegia Risk Assessment and Stratification (VARAS) score was shown to predict risk of vasoplegia in our population. We recommend all open-heart patients be stratified using the VARAS score to clinically anticipate risk of vasoplegia. Vasoplegia is associated with ICU length of stay (+2.8 days, 95% CI 2.1 - 3.6 days) and total hospital length of stay (+4.1 days, 95% CI 2.0 - 6.3 days). Vasoplegia increases the risk of 30-day mortality [OR 3.2, 95% (CI 1.25 - 6.87)] but not 30-day readmission [OR 1.35, 95% CI (0.94 - 1.94).


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