Objectives: Guidelines for post-cardiac arrest care recommend blood pressure optimization as one component of neuroprotection. Although some retrospective clinical studies suggest that postresuscitation hypotension may be harmful, and laboratory studies suggest that a postresuscitation hypertensive surge may be protective, empirical data are few. In this study, we prospectively measured blood pressure over time during the postresuscitation period and tested its association with neurologic outcome.
Design: Single center, prospective observational study from 2009 to 2012.
Patients: Inclusion criteria were age 18 years old or older, prearrest independent functional status, resuscitation from cardiac arrest, and comatose immediately after resuscitation.
Measurements and main results: Our research protocol measured blood pressure noninvasively every 15 minutes for the first 6 hours after resuscitation. We calculated the 0- to 6-hour time-weighted average mean arterial pressure and used multivariable logistic regression to test the association between increasing time-weighted average mean arterial pressures and good neurologic outcome, defined as Cerebral Performance Category 1 or 2 at hospital discharge. Among 151 patients, 44 (29%) experienced good neurologic outcome. The association between blood pressure and outcome appears to have a threshold effect at time-weighted average mean arterial pressure value of 70 mm Hg. This threshold (mean arterial pressure > 70 mm Hg) had the strongest association with good neurologic outcome (odds ratio, 4.11; 95% CI, 1.34-12.66; p = 0.014). A sustained intrinsic hypertensive surge was relatively uncommon and was not associated with neurologic outcome.
Conclusions: We found that time-weighted average mean arterial pressure was associated with good neurologic outcome at a threshold of mean arterial pressure greater than 70 mm Hg.