Impact of Fluid Balance on Extubation Outcomes in Critically Ill Patients: A Retrospective Analysis

INTRODUCTION: Extubation readiness in the ICU involves assessing multiple physiological and clinical factors. Recent research has shown the role of fluid balance in successful weaning from mechanical ventilation, with a positive fluid balance associated with extubation failure.(1,3) This retrospective analysis examined the impact of fluid balance on extubation outcomes in critically ill patients. This study aimed to quantify this relationship and identify the potential threshold values for fluid balance that could predict extubation outcomes. These findings could guide fluid management strategies before extubation and improve the weaning success rates. OBJECTIVES: To investigate the association between fluid balance and extubation success in critically ill patients undergoing mechanical ventilation in the intensive care unit. MATERIALS AND METHODS: This retrospective study included adult patients (≥18 years) admitted to a 20-bed ICU who underwent mechanical ventilation for more than 48 hours between January 2020 and December 2022. Data on daily fluid input and output were retrieved from electronic health records. The primary outcome was extubation success, defined as remaining free from mechanical ventilation for at least 48 hours post-extubation.(2) Patients were categorised based on fluid balance in the 24 hours before extubation: negative (<0 mL) or positive (≥0 mL). Logistic regression was performed to examine the relationship between fluid balance and extubation success, adjusting for age, severity of illness scores, and comorbidities. RESULTS: 245 patients (mean age 62 ± 14 years; 59% male) were included. Of these, 150 (61%) achieved successful extubation. Patients in the successful extubation group had a median fluid balance of -500 mL (IQR -800 to -200), whereas those who failed extubation had a median fluid balance of +250 mL (IQR -100 to +600). A negative fluid balance before extubation was significantly associated with higher odds of success (OR 2.35; 95% CI: 1.30–4.25; p=0.003) after adjusting for severity of illness and comorbidities. Additionally, patients with negative fluid balance demonstrated a shorter ICU length of stay (median 9 days vs. 13 days, p=0.01) and fewer ventilator-associated complications.(4,6) CONCLUSIONS: These findings suggest that maintaining a negative fluid balance before extubation may improve extubation success in critically ill patients. Strategies aimed at optimising fluid management should be considered in extubation protocols to enhance patient outcomes.(5)