Associations between mean arterial pressure and 28-day mortality according to the presence of hypertension or previous blood pressure level in critically ill sepsis patients

Gun Tak Lee, Sung Yeon Hwang, Ik Joon Jo, Tae Rim Kim, Hee Yoon, Joo Hyun Park, Won Chul Cha, Min Seob Sim, Tae Gun Shin

Abstract

Background: We aimed to investigate the association between average mean arterial pressure (a-MAP) and mortality in critically ill sepsis patients according to the presence of hypertension and previously measured blood pressure (BP).
Methods: From August 2008 to September 2014, patients with severe sepsis or septic shock presenting to the ED were categorized into four groups according to a-MAP during the initial 24 hours (group 0, a-MAP <65 mmHg; group 1, 65 mmHg ≤ a-MAP <75 mmHg; group 2, 75 mmHg ≤ a-MAP <85 mmHg; group 3, a-MAP ≥85 mmHg). A low previous BP was defined as previous a-MAP ≤85 mmHg, and a high previous BP is defined as a-MAP >85 mmHg. The primary outcome was 28-day mortality.
Results: A total of 1,395 patients were included. The 28-day mortality rates were 15.1% in patients overall, 39.7% in group 0, 18.3% in group 1, 10.1% in group 2, and 13.4% in group 3. In the regression analyses, mortality in group 2 was significantly lower compared with group 1 [odds ratio (OR), 0.33] or group 3 (OR, 0.31) in patients with hypertension. In the low previous BP group, there was greater mortality in group 3 compared to group 1 (OR, 2.42) and group 2 (OR, 3.88). In the high previous BP group, mortality was lower in group 2 compared with group 1 (OR, 0.32).
Conclusions: In critically ill sepsis patients, there were different trends in mortality according to a-MAP depending on the presence of hypertension or previous BP.