Protocol Compliance Guiding Angiotensin II Use in Post Cardiovascular Surgery Vasoplegia

Catecholamines and vasopressin are commonly used in patients with post cardiovascular surgery vasoplegia (PCSV). Multimodal therapy, including methylene blue (MB), hydroxocobalamin, and angiotensin II (Ang II), may improve outcomes in patients who remain hypotensive despite catecholamine and vasopressin therapy. However, a standardized approach has not been established. We created a protocol at Emory Healthcare (Emory Protocol), which provides guidance on norepinephrine equivalent dose (NED) and the use of noncatecholamines in the setting of PCSV and sought to determine the clinical significance of adherence to the protocol.

Retrospective study.

Multisite study at Emory University Hospital.

Patients receiving Ang II for PCSV in any cardiovascular ICU from 2018 to 2020.

Patient encounters were scored on Emory Protocol compliance based on NED (1-5), use of vasopressin (1-2), use of MB (1-2), and documentation of high-output shock (1-4). A compliant score was less than 7, moderately compliant 7 to 8, and poorly compliant greater than 8. Demographics, clinical data, and outcomes were abstracted from the medical records.

Of the 78 consecutive patients receiving Ang II for PCSV, overall ICU mortality was 26.9%, with an average compliance score of 6.2. ICU mortality was 21.1% for compliant cases (n = 38), 29.7% for moderately compliant cases (n = 24), and 37.5% for poorly compliant cases (n = 16). In regression analysis, the cumulative compliance score to the Emory Protocol was predictive of ICU mortality (p = 0.027).

Compliance with the Emory Protocol, emphasizing early initiation of the noncatecholamines vasopressin, MB, hydroxocobalamin, and Ang II at lower catecholamine doses in high-output shock, is associated with improved ICU mortality.