Renal Impact of Prolonged Sevoflurane Sedation in Intensive Care Unit Patients: An Observational Study

BACKGROUND: Due to their rapid onset and minimal accumulation, volatile agents are used for prolonged sedation in intensive care unit (ICU) patients. However, potential renal effects, particularly polyuria and nephrogenic diabetes insipidus, remain a concern during sevoflurane use. OBJECTIVE: To evaluate the prevalence of and the factors associated with polyuria during prolonged sevoflurane sedation in ICU patients. METHODS: This observational study included consecutive ICU patients (July 2019 to July 2023) receiving sevoflurane, excluding those with prior renal replacement therapy. Sevoflurane was administered via an anesthetic conserving device at physicians' discretion. Demographic data, clinical characteristics, and laboratory parameters were collected from ICU records. Multivariate analysis was used to identify factors associated with polyuria. RESULTS: Among 76 patients, 32 (42%) with a median (IQR) sevoflurane duration of 118 (76-165) hours developed polyuria (>3000 mL/d) during the first 7 days. Polyuria was associated with higher urine output, serum sodium level, and osmolarity. Multivariate analysis revealed that prolonged sevoflurane exposure (>1 day) increased the risk of polyuria (odds ratio [95% CI], 1.26 [1.08-1.53]; P = .009). Acute kidney injury was negatively associated with polyuria (odds ratio [95% CI], 0.25 [0.07-0.79]; P = .02). Baseline renal function, weight, and diuretic dose did not differ between patients with and patients without polyuria. CONCLUSIONS: Polyuria is a complication of prolonged sevoflurane sedation; prevalence increases with exposure duration. These findings highlight the need to monitor urine output and serum sodium level during sedation.