To determine if the route of administration of whole blood cardioplegia (cardioplegia) is significantly associated with the frequency of profound transient hypotension (intermittent “vasoplegia”) often observed during cardioplegia administration.

Retrospective analysis of automatically captured hemodynamic data from the electronic perfusion record (EPIC; Verona, WI).

A tertiary care academic medical center.

One hundred thirteen adult cardiac surgical patients requiring cardiopulmonary bypass.

Antegrade versus retrograde subsequent cardioplegia administration(s).

Subsequent (postinduction) cardioplegia administrations were analyzed exclusively, and all doses were delivered over a standardized 20- to 25-minute ischemic period using the same cardioplegia formulation. Each subject’s mean arterial pressure (MAP) variability during cardiopulmonary bypass was quantified when cardioplegia was not being administered (baseline). Significant hypotension during cardioplegia administrations was defined as a minute-to-minute MAP reduction exceeding three standard deviations (3 SDs) from the subject-specific baseline MAP variability (allowing each subject to serve as their own control). Retrograde cardioplegia administrations exhibited a higher incidence of significant hypotension (35.8% of 246 cases) compared to antegrade delivery (22.2% of 99 cases; p = 0.021). Patient-level analysis revealed 60.2% of retrograde recipients versus 31.4% of antegrade recipients experienced at least one 3 SD MAP decline (p = 0.003).

The incidence of intermittent vasoplegia during cardioplegia administration was significantly higher when delivered retrograde.