Minimum Mean Arterial Pressure and Associated Mortality Outcomes in the Cardiac Intensive Care Unit

Area of Science:

• Cardiology
• Critical Care Medicine
• Clinical Physiology

Background:

• Hypotension is a known risk factor for mortality in critical care.
• Limited data exists on the prognostic value of minimum mean arterial pressure (minMAP) specifically in cardiac critical illness.

Purpose of the Study:

• To evaluate the prognostic significance of minMAP within the initial 24 hours of cardiac intensive care unit (CICU) admission.
• To determine the association between varying levels of minMAP and patient mortality outcomes.

Main Methods:

• Retrospective analysis of adult CICU patients from 2007-2018.
• Classification and regression tree model used to define minMAP groups.
• Multivariable logistic and Cox regression models adjusted for confounders to assess mortality risk.

Main Results:

• A graded, reverse J-shaped association was observed between lower minMAP and increased mortality.
• Patients with minMAP <48 mm Hg showed significantly higher in-hospital and 30-day mortality.
• The lowest mortality rates were observed when minMAP ranged from 71 to 75 mm Hg.

Conclusions:

• Lower minMAP is incrementally associated with higher mortality in CICU patients.
• Severe hypotension, indicated by low minMAP, is a critical physiological marker of patient vulnerability.
• These findings underscore the importance of monitoring minMAP in cardiac critical care settings.