A treatment used as a “last resort” for severe cases of COVID-19 could soon reach capacity as hospitals nationwide strain to meet the demands of a growing domestic outbreak.

In Japan, 24 patients with severe infections have been treated or continue to be treated using extracorporeal membrane oxygenation, or ECMO, a resource intensive but cutting-edge machine used occasionally to remedy serious lung and heart problems.

There are upwards of 1,300 ECMO machines available in the country, according to a survey released in March by the Japanese Society of Respiratory Care Medicine and the Japan Association of Clinical Engineers.

But only about 300 of these machines are available for treating COVID-19, said Satoru Hashimoto, the director of intensive care medicine at the hospital of the Kyoto Prefectural University of Medicine.

“If things get worse, we don’t have enough ECMO machines and hospitals are already full of patients,” Hashimoto said. “I don’t know what’s going to happen next.”

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Hospitals can’t set aside all ECMO machines since the treatment is also used for patients with severe heart and lung issues, he explained, adding that even hospitals with five machines aren’t able to spare any for COVID-19 treatment.

In some cases, hospital resources are being stretched so thin that doctors have had to transfer patients using their own personal cars, Hashimoto said. Health care providers are being forced to make up for the absence of an “ECMO Center” commonly found in other developed countries, Hashimoto added, as well as a lack of logistical support from local governments.

In February, Hashimoto and a team of health care professionals created ECMOnet, a registry coupled with a 24-hour hotline that allows more than 400 participating hospitals to exchange up-to-date information, pool resources and, in some cases, transfer patients to a facility where an ECMO machine is available.

The treatment involves running the blood of a patient with respiratory or cardiac failure through an artificial lung. The method was used heavily during the swine flu outbreak in 2009 and proved effective with a 90 percent survival rate in countries like England and Sweden. In Japan, however, the survival rate of patients treated with ECMO was around 30 percent, Hashimoto said.

After the outbreak died down, dozens of Japanese scientists traveled to Sweden to receive the training needed to properly administer ECMO.

“We were lagging behind the rest of the world,” Hashimoto said. “The time has come to show our progress, and so far we’ve had very good results.”

Nine of the 24 COVID-19 patients treated with ECMO in Japan have recovered completely or have already been weaned successfully onto more conventional treatment methods like oxygen tanks or mechanical ventilators. So far, no patients treated with ECMO in Japan have died.

But while this specialized treatment may be showing promise, other experts say the bigger issue is whether hospitals will be able to cope with the influx of patients seeking intensive care.

“From what we see, ECMO is still a small but important part of the tools we have,” said Kiran Shekar, deputy head of the Critical Care Research Group at Prince Charles Hospital in Brisbane, Australia. “ECMO has a role to play in a pandemic but thankfully, from what we’ve seen so far, this is not a pandemic where we say the treatment of choice is ECMO.”

About 80 percent of COVID-19 patients experience mild symptoms while around 15 percent need hospital-based care, according to the World Health Organization. The remaining 5 percent require intensive care, and only a small number qualify for ECMO. Even then, ECMO is seen as a last resort — only to be used when conventional methods fail to yield positive results.

What warrants more concern, Shekar said, is whether hospitals will be able to withstand the inevitable rush of patients.

“The biggest challenge most intensive care units around the world are facing is looking after a lot of sick patients at once,” he went on. “Providing high quality intensive care to a lot of people at once is a major challenge in itself because centers are now being told to expand their intensive care capacity by two, three times, which is not something you can do overnight.”

RELATED PHOTOS An ambulance carrying a Japanese national who returned from China's Wuhan arrives at a Tokyo hospital in January. Hospitals in the country are being increasingly stretched thin due to the outbreak of the new coronavirus. | KYODO