Hypotension within one-hour from starting CRRT is associated with in-hospital mortality

Abstract

Purpose: To investigate early hemodynamic instability and its implications on adverse outcomes in patients who require continuous renal replacement therapy (CRRT).

Materials and methods: A retrospective study of patients admitted to the intensive care unit (ICU) and underwent CRRT at Mayo Clinic, Rochester, Minnesota between December 2006 through November 2015.

Results: Multivariate logistic regression was performed to identify predictors of in-hospital mortality and major adverse kidney events (MAKE) at 90 days. Hypotension was defined as any of the following criteria occurring during the first hour of CRRT initiation: mean arterial pressure < 60 mmHg, systolic blood pressure (SBP) <90 mmHg or a decline in SBP >40 mmHg from baseline, a positive fluid balance >500 mL or increased vasopressor requirement. The analysis included 1743 patients, 1398 with acute kidney injury (AKI). In-hospital mortality occurred in 884 patients (51%). Early hypotension occurred in 1124 patients (64.6%) and remained independently associated with in-hospital mortality (OR 1.56, 95% CI: 1.25-1.9).

Conclusion: Hypotension occurs frequently in patients receiving CRRT despite having a reputation as the dialysis modality with better hemodynamic tolerance. It is an independent predictor for worse outcomes. Further studies are required to understand this phenomenon.

Keywords: AKI; Hemodialysis; Ionized calcium; Mortality; Nephrology.