Impact of positive fluid balance on mortality and length of stay in septic shock patients

BACKGROUND: Fluid management is important in critically patients. The aim of this study was to determine the relationship between fluid balance and adverse outcomes of septic shock. METHODS: A retrospective study was conducted in the medical Intensive Care Unit (ICU) of a tertiary university hospital in Thailand, over a 7-year period. RESULTS: A total of 1048 patients with an ICU mortality rate of 47% were enrolled. The median cumulative fluid intake at 24, 48, and 72 h from septic shock onset were 4.2, 7.7, and 10.5 L, respectively. Nonsurvivors had a significantly higher median cumulative fluid intake at 24, 48, and 72 h (4.6 vs. 3.9 L, 8.2 vs. 7.1 L, and 11.4 vs. 9.9 L, respectively, P < 0.001 for all). Nonsurvivors also had a significantly higher cumulative and mean fluid balance within 72 h (5.4 vs. 4.4 L and 2.8 vs. 1.6 L, P < 0.001 for both). In multivariate logistic regression analysis, mean fluid balance quartile within 72 h, was independently associated with an increase in ICU and hospital mortality. Quartile 3 and 4 have statistically significant increases in mortality compared with quartile 1 (odds ratio [95% confidence interval] 3.04 [1.9–4.48] and 4.16 [2.49–6.95] for ICU mortality and 2.75 [1.74–4.36] and 3.16 [1.87–5.35] for hospital mortality, respectively, P < 0.001 for all). In addition, the higher amount of mean fluid balance was associated with prolonged ICU stays. CONCLUSIONS: Positive fluid balance over 3 days is associated with increased ICU and hospital mortality along with prolonged ICU stays in septic shock patients.