Influenza-Related ARDS Leads To Demand for Oxygenation

Among patients in Australia and New Zealand who were infected with 2009 influenza A(H1N1) during the winter season and developed acute respiratory distress syndrome, 79% of those who were treated with extracorporeal membrane oxygenation survived.

“Our findings have implications for health care planning and the clinical management of patients with 2009 influenza A(H1N1) during the 2009–2010 northern hemisphere winter,” wrote Dr. Andrew R. Davies of Monash University, Melbourne, and his colleagues (JAMA 2009 Oct. 12;doi:10.1001/JAMA.2009.1535). The study findings suggest that about 1,300 U.S. patients could need extracorporeal membrane oxygenation (ECMO) for acute respiratory distress syndrome related to 2009 H1N1 during the 2009–2010 winter season, the researchers said.

The study by the Australia and New Zealand Extracorporeal Membrane Oxygenation Influenza Investigators included all adult and pediatric patients who were treated with ECMO between June 1 and Aug. 31, 2009, in 15 ICUs in the two countries.

Of the 252 patients admitted with influenza to the participating ICUs, 201 received mechanical ventilation. The 68 patients who received ECMO had a mean age of 34 years; half were male and 61 had confirmed H1N1 infection. The most common comorbidities were obesity, asthma, and diabetes. Six patients were pregnant, and four were post partum. Three patients were younger than 15 years. Of the 68 ECMO patients, 48 survived to ICU discharge (32 were discharged from the hospital and 16 were still hospital inpatients), 14 (21%) died, and 6 remained in the ICU as of early September.

Among the 14 patients who died, the cause of death was intracranial hemorrhage (6 patients), other hemorrhage (4), and intractable respiratory failure (4). Of the 10 pregnant/postpartum patients, 7 survived. All three of the children treated with ECMO were alive, though one was still in the ICU.

During ECMO, hemorrhagic complications occurred in 54% of patients and infective complications in 62%.

“Our results indicate that the incidence of ARDS [acute respiratory distress syndrome] sufficient to warrant consideration of ECMO … exceeds 2.6 per million inhabitants” with confirmed or suspected 2009 influenza A(H1N1) during the winter season. When only confirmed cases were considered, the estimated incidence of ECMO use fell to 2.0 cases per million. In the preceding winter season, 0.15 cases per million were treated with ECMO for ARDS.

Compared with 133 patients with confirmed H1N1 who were treated with mechanical ventilation but not ECMO, those treated with ECMO had longer median durations of mechanical ventilation (18 days vs. 8 days), longer median ICU stays (22 vs. 12), and greater ICU mortality (14 vs. 12).

The authors had no relevant financial relationships.

Among patients in Australia and New Zealand who were infected with 2009 influenza A(H1N1) during the winter season and developed acute respiratory distress syndrome, 79% of those who were treated with extracorporeal membrane oxygenation survived.

“Our findings have implications for health care planning and the clinical management of patients with 2009 influenza A(H1N1) during the 2009–2010 northern hemisphere winter,” wrote Dr. Andrew R. Davies of Monash University, Melbourne, and his colleagues (JAMA 2009 Oct. 12;doi:10.1001/JAMA.2009.1535). The study findings suggest that about 1,300 U.S. patients could need extracorporeal membrane oxygenation (ECMO) for acute respiratory distress syndrome related to 2009 H1N1 during the 2009–2010 winter season, the researchers said.

The study by the Australia and New Zealand Extracorporeal Membrane Oxygenation Influenza Investigators included all adult and pediatric patients who were treated with ECMO between June 1 and Aug. 31, 2009, in 15 ICUs in the two countries.

Of the 252 patients admitted with influenza to the participating ICUs, 201 received mechanical ventilation. The 68 patients who received ECMO had a mean age of 34 years; half were male and 61 had confirmed H1N1 infection. The most common comorbidities were obesity, asthma, and diabetes. Six patients were pregnant, and four were post partum. Three patients were younger than 15 years. Of the 68 ECMO patients, 48 survived to ICU discharge (32 were discharged from the hospital and 16 were still hospital inpatients), 14 (21%) died, and 6 remained in the ICU as of early September.

Among the 14 patients who died, the cause of death was intracranial hemorrhage (6 patients), other hemorrhage (4), and intractable respiratory failure (4). Of the 10 pregnant/postpartum patients, 7 survived. All three of the children treated with ECMO were alive, though one was still in the ICU.

During ECMO, hemorrhagic complications occurred in 54% of patients and infective complications in 62%.

“Our results indicate that the incidence of ARDS [acute respiratory distress syndrome] sufficient to warrant consideration of ECMO … exceeds 2.6 per million inhabitants” with confirmed or suspected 2009 influenza A(H1N1) during the winter season. When only confirmed cases were considered, the estimated incidence of ECMO use fell to 2.0 cases per million. In the preceding winter season, 0.15 cases per million were treated with ECMO for ARDS.

Compared with 133 patients with confirmed H1N1 who were treated with mechanical ventilation but not ECMO, those treated with ECMO had longer median durations of mechanical ventilation (18 days vs. 8 days), longer median ICU stays (22 vs. 12), and greater ICU mortality (14 vs. 12).

The authors had no relevant financial relationships.

Among patients in Australia and New Zealand who were infected with 2009 influenza A(H1N1) during the winter season and developed acute respiratory distress syndrome, 79% of those who were treated with extracorporeal membrane oxygenation survived.

“Our findings have implications for health care planning and the clinical management of patients with 2009 influenza A(H1N1) during the 2009–2010 northern hemisphere winter,” wrote Dr. Andrew R. Davies of Monash University, Melbourne, and his colleagues (JAMA 2009 Oct. 12;doi:10.1001/JAMA.2009.1535). The study findings suggest that about 1,300 U.S. patients could need extracorporeal membrane oxygenation (ECMO) for acute respiratory distress syndrome related to 2009 H1N1 during the 2009–2010 winter season, the researchers said.

The study by the Australia and New Zealand Extracorporeal Membrane Oxygenation Influenza Investigators included all adult and pediatric patients who were treated with ECMO between June 1 and Aug. 31, 2009, in 15 ICUs in the two countries.

Of the 252 patients admitted with influenza to the participating ICUs, 201 received mechanical ventilation. The 68 patients who received ECMO had a mean age of 34 years; half were male and 61 had confirmed H1N1 infection. The most common comorbidities were obesity, asthma, and diabetes. Six patients were pregnant, and four were post partum. Three patients were younger than 15 years. Of the 68 ECMO patients, 48 survived to ICU discharge (32 were discharged from the hospital and 16 were still hospital inpatients), 14 (21%) died, and 6 remained in the ICU as of early September.

Among the 14 patients who died, the cause of death was intracranial hemorrhage (6 patients), other hemorrhage (4), and intractable respiratory failure (4). Of the 10 pregnant/postpartum patients, 7 survived. All three of the children treated with ECMO were alive, though one was still in the ICU.

During ECMO, hemorrhagic complications occurred in 54% of patients and infective complications in 62%.

“Our results indicate that the incidence of ARDS [acute respiratory distress syndrome] sufficient to warrant consideration of ECMO … exceeds 2.6 per million inhabitants” with confirmed or suspected 2009 influenza A(H1N1) during the winter season. When only confirmed cases were considered, the estimated incidence of ECMO use fell to 2.0 cases per million. In the preceding winter season, 0.15 cases per million were treated with ECMO for ARDS.

Compared with 133 patients with confirmed H1N1 who were treated with mechanical ventilation but not ECMO, those treated with ECMO had longer median durations of mechanical ventilation (18 days vs. 8 days), longer median ICU stays (22 vs. 12), and greater ICU mortality (14 vs. 12).

The authors had no relevant financial relationships.