Continuous veno-venous hemofiltration may improve survival from acute respiratory distress syndrome after bone marrow transplantation or chemotherapy

Purpose: Acute respiratory distress syndrome (ARDS) may result from immunologic activity triggered by irradiation and/or chemotherapy. Hemofiltration removes plasma water and soluble components below 25 kilodaltons. The authors hypothesized that early hemofiltration might attenuate the inflammatory component of ARDS, resulting in increased survival in immunocompromised children and young adults. Methods: Ten children (6 bone marrow transplantation, 3 chemotherapy, I lymphoma/hemophagocytosis) with ARDS (Pao(2)/Fio(2) 94 +/- 37 torr) received early continuous veno-venous hemodiafiltration as adjunctive therapy for respiratory failure, regardless of renal function. Six children had normal urine output and initial serum creatinine (range 0.1-1.2 mg/dL); four had renal insufficiency (initial creatinine 1.7-2.4 mg/dL). Hemofiltration was instituted coincident with intubation. Respiratory failure was precipitated by Enterobacter sepsis in two patients and by Aspergillus in one. Results: Hemodiafiltration was performed for 13 +/- 9 days. A high rate of clearance was achieved (52 +/- 17 mL/min/1.73 m(2)). Duration of mechanical ventilation was 14 +/- 9 days. Nine of the 10 children were successfully extubated; 8 survived. Conclusions: Early hemofiltration may improve survival from ARDS following bone marrow transplantation or chemotherapy. Possible mechanisms include strict fluid balance, immunomodulation through filtration of inflammatory constituents, and immunomodulation through intensive extracellular water exchange that delivers biochemicals to organs of metabolism as well as the hemofilter.