R. Devasagayaraj1, N. Cavarocchi1, H. Hirose1 1Thomas Jefferson University,Philadelphia, PA, USA
Introduction: Patients who develop severe acute respiratory distress syndrome (ARDS) with stable hemodynamics may be placed on veno-venous extracorporeal membrane oxygenation (VV ECMO) to support respiratory recovery. Survival outcomes remain unclear in those who develop acute kidney injury (AKI) requiring continuous veno-venous hemodialysis (CVVHD).
Methods: A retrospective chart review (2010-2016) of patients who underwent VV ECMO for ARDS was conducted with IRB approval. Patients supported by veno-arterial ECMO due to cardiac failure or hemodynamic instability were excluded. Analyses of patient demographics, clinical risk factors, respiratory parameters, and laboratory data were conducted. AKI was defined by receiving CVVHD, which was used for patients with oliguria despite administration of diuretics, acute renal failure, severe metabolic acidosis, and/or uncontrollable fluid overload. VV ECMO was performed via right internal jugular access using dual lumen ECMO cannula, while CVVHD was performed via groin access using a separate dialysis catheter. Patients on VV ECMO were divided by development of AKI into two groups, AKI and non-AKI and survival analysis was performed.
Results: We identified 54 ARDS patients (aged 45 ± 13y, 33 males) supported by VV ECMO (mean ECMO days 12 ± 6.7) including 16 (29.6%) in AKI group and 38 (70.4%) in non-AKI group. No patients had previous renal failure, and serum creatinine was similar between AKI and non-AKI group at the time of ECMO initiation (1.8 ± 1.1 mg/dl in AKI group vs. 1.4 ± 0.7 mg/dl in non-AKI group, p=0.194). Survival of AKI group (56.3% [9/16]) was inferior to the non-AKI group (86.8% [33/38]), p=0.013. At the time of initiation of ECMO, patients demographics, lung, renal, and liver functions were similar between AKI and non-AKI group. However, at the time of decannulation of ECMO, AKI group showed higher lactate (5.2 ± 5.1 mmol/L in AKI group vs 2.1 ± 1.2 mmol/L in non-AKI group, p=0.046), metabolic acidosis (bicarbonate level, 23 ± 3.4 mmol/L vs. 27 ± 9.9 mmol/L, p=0.032), despite similar creatinine levels (1.2 ± 0.6 mg/dL vs. 1.0 ± 0.5 mg/dL, p=0.272). AKI group showed greater incidence of complications during ECMO including liver failure (37.5% [6/16] vs. 5.2% [2/38], p=0.002) and internal hemorrhage (68.8% [11/16] vs. 21% [8/38], p<0.001). Among the survivors of ECMO, 79.2% [38/48] survived hospital stay and 43.8% [7/16] recovered renal function without need of permanent dialysis.
Conclusion: In our experience, patients initially placed on VV ECMO for single organ injury due to ARDS when complicated by AKI showed decreased survival. Patients developing AKI are likely to develop hepato-renal syndrome and internal bleeding, all which may lead to multi-organ failure. VV ECMO alone successfully manages patients with severe ARDS; however, other end-organ function needs careful monitoring and appropriate treatment to improve outcome.