Mean Arterial Pressure Goal in Critically Ill Patients: A Meta-Analysis of Randomized Controlled Trials

Abstract

BackgroundCurrent guidelines recommend targeting a mean arterial pressure (MAP) goal of 65 mm Hg or more in critically ill medical patients. Prospective studies have shown that a higher MAP goal can improve survival and decrease end-organ damage. However, randomized controlled trials (RCTs) have failed to show similar results. Thus, we performed this meta-analysis to evaluate whether a high MAP goal compared to a standard or low MAP goal will improve clinical outcomes in critically ill medical patients.MethodsWe searched electronic databases for RCTs comparing standard MAP goals versus high MAP goals in critically ill medical patients. A standard MAP goal was defined as a MAP of 60 - 70 mm Hg, and a MAP of 70 mm Hg or more was considered a high MAP goal. Outcomes of interest were mortality, duration of mechanical ventilation, and intensive care unit (ICU) length of stay. Subgroup analysis was performed based on the type of critically ill patients: cardiac arrest and septic shock. We used random-effects meta-analysis to estimate risk ratio (RR) with a 95% confidence interval (CI) for a dichotomous outcome. For continuous outcomes, the inverse variance method was used to calculate the standardized mean difference (SMD) with 95% CI. A P value of 0.05 or less was considered significant.ResultsSix RCTs with a total of 3,753 patients (standard MAP goal: n = 1,872 and high MAP goal: n = 1,881) were included in the final analysis. Both standard/low MAP goal and high MAP goal were associated with similar risk for mortality (RR 0.94, 95% CI (0.87, 1.01), P = 0.11), duration of mechanical ventilation (SMD 0.51, 95% CI (-0.29, 1.31), P = 0.21) and ICU length of stay (SMD 0.22, 95% CI (-0.07, 0.5), P = 0.14). Subgroup analysis in cardiac arrest patient showed decreased ICU stay (SMD 0.55, 95% CI (0.31, 0.80), P < 0.000001) in patients with higher MAP goal compared to the standard MAP goal group without any difference in mortality or duration of mechanical ventilation. Subgroup analysis of patients with septic shock had similar outcomes in both MAP targets.ConclusionsIn critically ill patients, a higher MAP goal of > 70 mm Hg was associated with a similar risk of mortality, duration of mechanical ventilation, and ICU length of stay when compared with a standard MAP goal of 60 - 70 mm Hg.