Short-Term Reactions to Oliguria in Critically Ill Patients: A Retrospective Cohort Study

Background/Objective: Oliguria is common in critically ill patients and may indicate impaired kidney perfusion or acute injury, contributing to increased mortality. Effective management is essential to improve outcomes. To assess clinician reactions to oliguria and evaluate the effectiveness of fluid bolus and furosemide interventions. Methods: A retrospective cohort study was conducted using ICU data from a single center (2017-2023). Oliguria was defined as two consecutive hours of urine output < 20 mL/h following at least three hours > 20 mL/h. Clinicians' reactions within four hours were categorized as no intervention, fluid bolus (>250 mL), or furosemide administration. Outcomes included urine output, fluid balance, and serum creatinine. Results: Among 4987 oliguria episodes, 4007 events in 1825 patients were analyzed: no reaction (2536), fluid bolus (923), and furosemide (548). Furosemide significantly increased urine output (53.9 to 75.3 mL/h, p < 0.001), while fluid bolus had no significant effect. Resolution of oliguria (mean urine output > 40 mL/h for 5 h post-intervention) was more frequent with furosemide (66.4%) than with fluid bolus (28.4%) or no reaction (27.6%) (p < 0.001). Treatment choices varied significantly among ICU attendings (p < 0.001). Conclusions: Furosemide was more effective than fluid bolus or no treatment in improving urine output and resolving oliguria. The observed variation in clinician practices underscores the need for standardized management protocols to enhance patient care.