Ultrasound-Based Clinical Profiles for Predicting the Risk of Intradialytic Hypotension in Critically Ill Patients on Intermittent Dialysis

Abstract

Background: Intradialytic hypotension (IDH) is a common and serious complication of intermittent hemodialysis (IHD) in critically ill patients with acute kidney injury (AKI). Accurate pre-dialysis risk stratification remains a challenge, particularly in the ICU. This study aims to determine whether ultrasound-based cardiopulmonary profiles could predict IDH in this high-risk population. Methods: This prospective cohort study included 100 critically ill adults undergoing IHD for AKI. All patients underwent pre-dialysis echocardiography and lung/inferior vena cava (IVC) ultrasound to assess stroke volume, cardiac output, B-lines, and IVC collapsibility index (IVC-CI). Patients were divided into two groups based on the presence or absence of IDH. Results: IDH occurred in 35% of patients. Significant predictors of IDH included lower systolic blood pressure (124.86 ±16.02 vs. 139.92 ±22.8 mmHg, P < 0.001), higher IVC-CI [51% (13–58) vs. 27.38% (13–60), P < 0.001], sepsis (88.6% vs. 70.8%, P = 0.044), and elevated potassium (5.17 ±1.34 vs. 4.62 ±0.87 mmol/L, P = 0.015). Multivariate analysis identified IVC-CI (OR = 1.097, P < 0.001) and SBP (OR = 0.942, P = 0.001) as independent predictors. IVC-CI >49.5% predicted IDH with 68.6% sensitivity and 87.7% specificity (AUC = 0.757, 95% CI: 0.652–0.862). Conclusion: Ultrasound-derived IVC-CI is a valuable, noninvasive tool for predicting IDH in critically ill patients receiving IHD. Incorporating sonographic profiles into routine pre-dialysis evaluation may enhance risk stratification and improve dialysis safety.