Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome caused by novel 2009 influenza A (H1N1) virus

Abstract

To summarize the clinical experiences and indications of extracorporeal membrane oxygenation (ECMO) for severe ARDS caused by novel 2009 influenza A (H1N1) virus. All ECMO cases with severe ARDS associated with novel 2009 influenza A (H1N1) virus were analyzed in 5 intensive care units (ICUs) from 5 different hospitals in Beijing and Tianjin. A physician experienced in ECMO handling collected the relevant data, including general conditions pre and post-EMCO, efficacy and complication parameters, ventilator settings of mechanical ventilation and clinical outcomes. The statistical software of SPSS (version 11.5) was used for data analysis. 18 cases of novel H1N1 influenza with severe ARDS received ECMO. There were 9 males and 9 females (all pregnant). The mean age was (33 ± 11) years old. Eight were complicated with pulmonary barotraumas (6 of pneumothorax). Prior to ECMO, the patients underwent noninvasive and invasive positive pressure ventilation for 1 day and 60 hours respectively. Physiological parameters 2-6 hours prior to ECMO use were: (53 ± 14) mm Hg of PaO2/FiO2, (17 ± 5) cm H2O of positive end expiratory pressure (PEEP), 3.80 ± 0.29 of Murray lung injury score, (7.38 ± 0.10) of arterial pH, (3.3 ± 2.3) mmol/L of serum lactate, 16 ± 8 of APACHE II score. All patients treated venous-venous ECMO (VV-ECMO) for a mean duration of 8 days (range: 2 - 168). Settings of mechanical ventilation (prior to ECMO vs 2 hours post-ECMO) were: peak airway pressure (31 ± 7) vs (25 ± 6) cm H2O, respiratory rate (15 ± 4) vs (22 ± 6) breaths/min, FiO2 0.8 - 1.0 vs 0.35 - 0.50, PEEP (16 ± 5) vs (12 ± 4) cm H2O. Arterial blood gas (pH, PaO2 and PaCO2) post-ECMO of 2 hours and 24-hour significantly improved (P < 0.05). Seven patients died during ECMO, 11 patients were successfully weaned from ECMO. And 8 of them survived and were discharged. One patient stayed in ICU and 2 died in ICU. As an effective measure of respiratory supports, ECMO may provide pulmonary rest and improve gas exchanges in severe ARDS induced by novel H1N1 Influenza.