997 Nadir Mean Arterial Blood Pressure During the First Day of Admission to the Intensive Care Unit (ICU) Is Associated With ICU Mortality

Abstract

INTRODUCTION: Current consensus guidelines endorsed by the American Society of Transplantation, American Society of Transplant Surgeons, and the European Association for the Study of the Liver recommend maintaining a mean arterial pressure (MAP) ≥ 60 mmHg to maintain organ perfusion in critically ill cirrhotics admitted to the intensive care unit (ICU). However, the associations between MAP and ICU-mortality, particularly during the first day of admission to the ICU, in critically ill cirrhotics remains unclear. AIM: To evaluate the association of nadir MAP during the first day of ICU admission and ICU-mortality in critically ill cirrhotics. METHODS: Cirrhotics admitted to the ICU at two academic tertiary care referral centers in 2017 were retrospectively analyzed. Nadir MAP one day after admission to the ICU was captured. Multivariable logistic regression analysis was performed to determine the association of day-1 nadir MAP with ICU-mortality. The Youden index was used to determine the optimal day-1 nadir MAP cut-off for discriminating risk for ICU-mortality. Kaplan-Meier (KM) survival curve was created with the optimal MAP cut-off for time to ICU-mortality. RESULTS: 183 cirrhotics were included [59 yrs, 56% male, 32% alcohol and 28% non-alcoholic in etiology, Model for End-Stage Liver Disease-Sodium (MELD-Na) score of 25]. Mean day-1 nadir MAP was significantly lower in patients who died in the ICU compared to those who did not (53 mmHg vs 65mmHg, P < 0.0001). After adjusting for potential confounding admission variables (vasopressor use, hemodialysis, mechanical ventilation, MELD-Na, and stage 3/4 hepatic encephalopathy), day-1 nadir MAP was independently associated with ICU-mortality with an OR of 1.13 (for 1 mmHg decrease, 95%CI 1.05, 1.22, P = 0.001). The optimal cut-off for day-1 nadir MAP was determined to be 60 mmHg. Forty-three percent of patients with a day-1 nadir MAP < 60 mmHg died during their ICU stay compared to 7% with a MAP > 60 mmHg. On KM analysis, time to ICU-mortality was significantly lower in patients with a MAP < 60 mmHg [P = 0.018 (Figure)]. CONCLUSION: In our preliminary analysis, we found nadir MAP during the first day of admission to the ICU to be independently associated with ICU-mortality. A cut-off of <60 mmHg may identify patients at risk for ICU-mortality, though larger studies at various time points are needed to substantiate this finding.