Relationship between short-term blood pressure variability and incidence of acute kidney injury in critically ill patients

Abstract

Background/Aims: Blood pressure (BP) variability is associated with cardiovascular events, and cerebral and renal damage. The aim of this study was to investigate any potential relationship between short-term BP variability and incidence of acute onset conditions, such as acute kidney injury (AKI), in critically ill patients. Methods: BP was monitored to analyze its variability in critically ill patients in present study. Short-term BP variability was assessed as average real variability (ARV), standard deviation (SD) and coefficient of variation (CV) of 24-hour BP. Results: A total of 565 patients were included, 41.2% (n=233) of which presented with AKI after admission (AKI stage I, n = 94; stage II, n = 37; stage III, n = 102). The mean APACHE II score was 21.5 for all patients. ARV of 24 h systolic BP was significantly higher in patients with AKI (p<0.001). This association remained (p=0.006) after adjustment for potential confounders. The incidence of AKI increased with the ARV from 14.0% (ARV ≤6 mmHg) to 73.9% (ARV >14 mmHg). A weak association was also found between BP variability and hospital mortality in critically ill patients. Conclusion: BP variability is correlated with the incidence of AKI in critically ill patients.