Extracorporeal Membrane Oxygenation Helps Battle Influenza A(H1N1)

A new study has found that the treatment of patients with severe acute respiratory failure (ARF) due to conditions such as H1N1 Influenza is better when extracorporeal membrane oxygenation (ECMO) is used.

Researchers at Glenfield Hospital (Leicester, United Kingdom), the London School of Hygiene and Tropical Medicine (LSHTM, UK), and other institutions conducted a randomized controlled trial that compared treatment by an ECMO team with care from specialist intensive care unit (ICU) teams using conventional ventilation, and also assessed the cost-effectiveness of referral for ECMO care. One hundred eighty adults aged 18-65 years were randomly assigned to receive continued conventional management or ECMO treatment. The primary outcome was death or severe disability at 6 months after randomization. Economic outcomes were quantified in quality-adjusted life-years (QALYs).

The researchers found that 75% of the patients assigned to consideration of ECMO actually received it. Of those referred for consideration of ECMO, 63% survived to six months without disability, compared to 47% of those who were assigned to conventional management, equivalent to one extra survivor without disability for every six patients treated. Consideration of ECMO treatment led to a gain of 0.03 QALYs at 6-month follow-up. The researchers found that the cost per ECMO case was twice that for conventional treatment, but that this was still well within the range regarded as cost-effective by the National Institute for Health and Clinical Excellence (NICE, London, United Kingdom).

"Swine flu causes a viral pneumonia which can result in severe respiratory failure in young adults,” said study coauthor Giles Peek, M.D., of the department of cardiothoracic surgery and ECMO at Glenfield Hospital. "We have already used ECMO during the first wave of the pandemic with good effect and we are expecting ECMO to prove an invaluable weapon in the fight against the winter resurgence of the infection, as has already been seen during the Australasian winter.”

ECMO uses heart-lung bypass technology to help patients whose heart and lungs are so severely diseased or damaged that they can no longer serve their function. To initiate ECMO, cannulae are placed in large blood vessels to provide access to the patient's blood. Anticoagulant drugs, usually heparin, are given to prevent blood clotting. The ECMO machine continuously pumps blood from the patient through a membrane oxygenator that removes carbon dioxide (CO2) and adds oxygen, which is then returned to the patient. ECMO has already been a vital tool for battling H1N1 influenza and is considered essential during the northern hemisphere winter, when cases could rise dramatically again.

Related Links:
Glenfield Hospital
London School of Hygiene and Tropical Medicine
National Institute for Health and Clinical Excellence