The impacts of blood pressure variability on clinical outcomes in patients with out-of-hospital cardiac arrest

Abstract

Background

The impact of blood pressure variability (BPV) following out-of-hospital cardiac arrest (OHCA) is not well established. This study aims to investigate the relationship between BPV after the return of spontaneous circulation and clinical outcomes in OHCA patients.

Methods

Non-traumatic OHCA patients were enrolled retrospectively. Continuous intra-arterial blood pressure monitoring was recorded and documented hourly. BPV was assessed using the standard deviation and coefficient of variation within the first 24- and 48-h. The clinical outcomes included 30-day mortality and poor neurological outcomes at discharge, defined as Cerebral Performance Category scale 3–5.

Results

A total of 217 non-traumatic OHCA patients who survived more than 24 h were enrolled. There were 119 deaths within 30 days and 165 poor neurological outcomes at discharge. High BPVs were independently associated with greater risk of 30-day mortality (standard deviation of mean arterial pressure: hazard ratio [HR] = 1.06, 95 % confidence interval [CI] = 1.03–1.10, P < 0.001; coefficient of variation of mean arterial pressure: HR = 1.06, 95 % CI = 1.03–1.08, P < 0.001) and poor neurological outcomes at discharge (standard deviation of mean arterial pressure: HR = 1.08, 95 % CI = 1.05–1.10, P < 0.001; coefficient of variation of mean arterial pressure: HR = 1.07, 95 % CI = 1.05–1.09, P < 0.001). Further analysis on the 185 patients surviving more than 48 h revealed similar findings.

Conclusion

Greater BPV during the early post-resuscitation phase is strongly linked to increased mortality and poor neurological outcomes in OHCA patients.