Abstract
BACKGROUND: Acute kidney injury (AKI) is the most common extra-pulmonary organ failure in acute respiratory distress syndrome (ARDS). Renal recovery after AKI is determined by several factors. The objective of this study was to determine the predictors of renal non-recovery in ARDS patients. METHODS: A single center retrospective cohort study of patients with AKI after onset of ARDS. Patients with preexisting chronic kidney disease or intensive care unit stay < 24 h were excluded. AKI staging was defined according to the Kidney Disease Improving Global Outcomes (KDIGO) 2012 guidelines. Renal non-recovery was defined as death, dialysis dependence, serum creatinine ≥1.5 times the baseline, or urine output < 0.5 mL/kg/h more than 6 h. RESULTS: Of the 244 patients that met study criteria, 60 (24.6%) had stage I AKI, 66 (27%) had stage II AKI, and 118 (48.4%) had stage III AKI. Of those, 148 (60.7%) patients had renal non-recovery. On multivariable analysis, factors associated with renal non-recovery were a higher stage of AKI (odds ratio [OR] stage II 5.71, 95% confidence interval [CI] 2.17-14.98; OR stage III 45.85, 95% CI 16.27-129.2), delay in the onset of AKI (OR 1.12, 95% CI 1.03-1.21), history of malignancy (OR 4.02, 95% CI 1.59-10.15), septic shock (OR 3.2, 95% CI 1.52-6.76), and a higher tidal volume on day 1-3 of ARDS (OR 1.41, 95% CI 1.05-1.90). Subgroup analysis of survival at day 28 of ARDS also found that higher severity of AKI (OR stage II 8.17, 95% CI 0.84-79.91; OR stage III 111.67, 95% CI 12.69-982.91), delayed onset of AKI (OR 1.12, 95% CI 1.02-1.23), and active malignancy (OR 6.55, 95% CI 1.34-32.04) were significant predictors of renal non-recovery. CONCLUSIONS: A higher stage of AKI, delayed onset of AKI, a history of malignancy, septic shock, and a higher tidal volume on day 1-3 of ARDS predicted renal non-recovery in ARDS patients. Among survivors, a higher stage of AKI, delayed onset of AKI, and a history of malignancy were associated with renal non-recovery.