Extracorporeal membrane oxygenation (ECMO) is an artificial lung device used with coronavirus patients with serious pneumonia symptoms. According to the Japanese Society of Intensive Care Medicine (JSICM) and other sources, 90 patients infected with the new coronavirus have been placed on the ECMO up to April 20. Two-thirds of the patients who finished treatment have recovered. Is Japan prepared for an increase in the number of patients in serious condition?
In general, coronavirus patients who develop pneumonia and have breathing difficulties receive oxygen inhalation. If the patient’s condition worsens, s/he is fitted with a respirator. The respirator tube is inserted from the nose, mouth, or via an opening made on the wind pipe in the neck. The respirator forces air in and creates a condition where the patient breathes artificially.
When the patient’s condition worsens, the lungs cannot take in oxygen unaided. The ECMO substitutes for the lungs’ function. The ECMO takes the patient’s blood from a vein at a leg joint, then adds oxygen to the blood and returns the oxygenated blood to the body. ECMO does not cure pneumonia, but it allows the lungs to rest and gives them a chance to recuperate.
According to the JSICM figures up to April 20, 52 out of the 90 new coronavirus patients who were treated with ECMO finished treatment. 35 patients recovered (67%) and 17 patients died. The remaining 38 patients are still undergoing treatment. Shinhiro Takeda, representative of the “Japan COVID-19 countermeasures ECMO net,” an organization comprised of physician members of JSICM and other organizations, said the recovery rate for patients with respiratory failure in cases other than the coronavirus who receive ECMO treatment is 70%. A similar result can be expected for new coronavirus patients.
What is the level of preparedness for medical equipment used with patients in serious condition? In mid-February 2020, the Japanese Society of Respiratory Care Medicine and the Japan Association for Clinical Engineers conducted a survey of hospitals with clinical engineers in residence. There were 22,254 respirators but only 1,412 ECMO machines in 1,588 facilities. By prefecture, Tokyo had the most ECMO machines with 196, followed by Osaka, Saitama, and Aichi, with 103, 74, and 70, respectively.
Upon making inquiries to foreign physicians regarding the ECMO, it was found that Germany has about 1,000 ECMO machines and other European countries even fewer, according to Takeda. “If we look at just the number of ECMO’s, the number for Japan is not small,” says Takeda
Not all ECMO machines can be used for new coronavirus patients. About 90% of the Japanese users thus far have been patients with cardiovascular conditions such as heart failure. At the time of the survey, about 160 machines were in use and a certain number are expected to be used by non-coronavirus patients in the future. Backup machines in case of malfunctions will be needed. Takeda estimates that only 500 to 700 machines at maximum can be used at any time.
Human resources are a more serious issue. Physicians and clinical engineers with a high level of skill are needed to install and operate the ECMO, but the absolute number of such personnel is small. Hospitals that admit new coronavirus patients may not have experience in treating patients with severe respiratory failure. Taking all these factors into account, the number of ECMO machines that can be used are actually fewer than the number available. Takeda says that there may be a need for “hospitals to discuss allocation of equipment and personnel” in the future.