Vasopressor Responsiveness Beyond Arterial Pressure: A Conceptual Systematic Review Using Venous Return Physiology

Area of Science:

• Critical care medicine
• Cardiovascular physiology
• Pharmacology

Background:

• Vasopressors are critical in managing shock, but their hemodynamic effects are complex.
• Current clinical endpoints, like mean arterial pressure (MAP), may not fully capture vasopressor response.
• A deeper understanding of vasopressor-induced hemodynamic shifts is needed.

Purpose of the Study:

• To systematically review and analyze the hemodynamic effects of vasopressors in adults with shock.
• To evaluate vasopressor responsiveness using a comprehensive physiological approach.
• To compare the utility of MAP alone versus a multi-domain analysis for assessing vasopressor effects.

Main Methods:

• Systematic review of 28 studies with 678 subjects from PubMed, EMBASE, and CENTRAL.
• Physiological analysis focusing on intravascular volume, heart pump performance, and vascular resistance.
• Correlation analysis between hemodynamic parameters and vasopressor administration.

Main Results:

• Vasopressors increased MAP and systemic vascular resistance.
• Mean systemic filling pressure analogue increased, while cardiac output changes were heterogeneous.
• Strong positive correlation between venous return gradient and MAP; negative correlation between mean systemic filling pressure analogue and heart pump efficiency.

Conclusions:

• Mean arterial pressure alone inadequately represents hemodynamic changes during vasopressor therapy.
• A comprehensive hemodynamic assessment provides better insights into vasopressor effects.
• Optimizing vasopressor administration requires considering multiple physiological domains beyond MAP.