Relation of positive fluid balance to the severity of renal impairment and recovery among ST elevation myocardial infarction complicated by cardiogenic shock

Purpose We analyzed the relationship between a positive fluid balance and its persistence over time on acute kidney injury (AKI) development, severity and resolution among ST elevation myocardial infarction (STEMI) patients complicated by cardiogenic shock. Methods We retrospectively studied the cumulative fluid balance intake and output at 96 h following hospital admission in 84 consecutive adult patients with STEMI complicated by cardiogenic shock. The cohort was stratified into two groups, based on the presence or absence of positive fluid balance on day 4. Patients’ records were assessed for the development of AKI, AKI severity and recovery. Results Patients having positive fluid balance were more likely to develop a more severe AKI stage (52% vs. 13%; p < 0.001), were less likely to have recovery of their renal function (29% vs. 75%, p = 0.001), and demonstrated positive correlation between the amount of fluid accumulated and the rise in serum creatinine (R = 0.42, p = 0.004). For every 1 l increase in positive fluid balance, the adjusted possibility for recovery of renal function decreased by 21% (OR = 0.796, 95% CI 0.67–0.93; p = 0.006). Conclusions A positive fluid balance was strongly associated with higher stage AKI and lower rate of AKI recovery in STEMI complicated by cardiogenic shock.