Arginine vasopressin as the primary vasopressor in high-risk patients undergoing major non-cardiac surgery: A...

Arginine vasopressin (AVP) is used as an adjunct to catecholamine vasopressors, but its role as a sole agent in high-risk non-cardiac surgery remains poorly defined.

To characterize the integrated hemodynamic effects of AVP when used as the primary intraoperative vasopressor.

In a propensity-matched physiological analysis, high-risk patients receiving AVP as the sole intraoperative vasopressor were matched to contemporaneous controls managed with catecholamine-based vasopressors. Serial hemodynamic data were analyzed, including arterial pressure, cardiac index, central venous pressure (CVP), venous return determinants, efficiency measures, and intraoperative fluid administration.

Fifteen AVP-treated patients were matched to 13 controls, with all covariates balanced (SMDs <0.10). Mean AVP infusion rate was 0.023 (0.005) IU min^-1. AVP patients received lower intraoperative fluids (p = 0.03) and had reduced net positive fluid balance (p = 0.02). Mean arterial pressure targets were maintained in both groups (AVP: 72-78 mmHg; controls: 70-76 mmHg). Cardiac index remained preserved with AVP (2.2-2.5 L min^-1 m^-2), comparable to controls (2.1-2.4 L min^-1 m^-2), despite lower CVP (AVP: 6-7 mmHg vs. 8-10 mmHg), consistent with effective recruitment of stressed volume and preserved cardiac function. Resistance to venous return remained stable over time, with no between-group differences (p > 0.05). AVP-treated patients demonstrated patterns consistent with improved circulatory efficiency compared with controls.

In high-risk non-cardiac surgery, AVP-based hemodynamic management was associated with stable circulatory dynamics, preserved venous return, and reduced fluid exposure. These findings provide a physiological rationale for considering AVP as an alternative hemodynamic strategy in selected surgical patients.