As scientists start to assess the impact that COVID-19 has had on patients and the American medical system more broadly, Bloomberg reports that hospitals across the US have seen a surge in patients receiving single- and double-lung transplants.
Transplants are necessary for only the most serious COVID-19 cases. In these patients - pretty much always patients with comorbidities - COVID-19 ravages the lung tissue, leaving nodules in the lungs incapable of absorbing oxygen from the air and transmitting it to the blood stream. For many patients, the grueling procedure may be the only solution after experiencing the worst lung damage caused by the virus - when the body fails to properly respond to, and heal from, the hyper-inflammatory response provoked by COVID-19.
John Micklus’s battle with Covid-19 began last Christmas and ended five weeks later with lungs so irreversibly damaged that doctors said there was nothing they could do to save him.
"The doctor’s recommendation was to get my affairs in order," Micklus said. The 62-year-old called his wife from his hospital bed in southern Maryland. She, in turn, desperately called several physicians, and eventually learned of one last option: A double-lung transplant.
Micklus was transferred to the University of Maryland Medical Center in Baltimore, where a rigorous assessment qualified him to receive lungs from a matched donor days later. He was discharged from the hospital on March 30, marking the center’s second successful lung transplant in a Covid survivor.
Micklus and other double-lung transplant survivors suffered from a phenomenon that scientists call the "honeycomb change."
All of that can cause the deposition of yellow fibrotic scar tissue, creating a “honeycomb change” that makes the lungs completely solid, said David Kleiner, who heads autopsy pathology in the National Institutes of Health Clinical Center in Bethesda, Maryland.
The process irreversibly destroys the tiny grape-like air sacs through which gas is exchanged in the lungs, Kleiner said in a lecture on Covid autopsies in July. “Patients really only survive to that fibrotic stage if they are intubated,” he said, adding that the harmful scarring can occur within a couple of weeks of lung injury.
A study published in the Lancet, the premier UK medical journal, aggregated what the scientific community has learned about the phenomenon. The report determined that "lung transplantation is the only option for survival in some patients with severe, unresolving COVID-19-associated ARDS."
Between May 1 and Sept 30, 2020, 12 patients with COVID-19-associated ARDS underwent bilateral lung transplantation at six high-volume transplant centres in the USA (eight recipients at three centres), Italy (two recipients at one centre), Austria (one recipient), and India (one recipient). The median age of recipients was 48 years (IQR 41–51); three of the 12 patients were female. Chest imaging before transplantation showed severe lung damage that did not improve despite prolonged mechanical ventilation and extracorporeal membrane oxygenation. The lung transplant procedure was technically challenging, with severe pleural adhesions, hilar lymphadenopathy, and increased intraoperative transfusion requirements. Pathology of the explanted lungs showed extensive, ongoing acute lung injury with features of lung fibrosis. There was no recurrence of SARS-CoV-2 in the allografts. All patients with COVID-19 could be weaned off extracorporeal support and showed short-term survival similar to that of transplant recipients without COVID-19.
Without the procedure, patients can't survive without a ventilator or a machine that oxygenates the blood via an artificial lung - an expensive proposition. The procedure is intense: Bloomberg described three patients, ages 28, 43 and 62, whose surgeries each took about 9.5 hours and two weeks of post-op recovery care.
Lung transplantation - especially a double-lung transplant - is still an expensive and risky proposition, and not everyone will succeed in finding a donor. But breakthroughs are making the procedure more manageable for surgeons.
Still, lung transplantation will likely remain a last resort, as even a lengthy rehab stint would be preferable to taking the risks of a transplant.
Doctors in Japan reported in April the world’s first “living donor” transplant in a Covid patient who received lung segments from her son and husband. The procedure at Kyoto University Hospital took a team of 30 medical personnel about 11 hours to perform.
“We demonstrated that we now have an option of lung transplants” from living donors, Hiroshi Date, a thoracic surgeon at the hospital who led the operation, told reporters.
Reed, who is also a professor of pulmonary and critical care medicine at the University of Maryland, said transplant surgery shouldn’t be seen as a way to speed up post-Covid recovery. Lung recipients need to take more than a dozen medications for the rest of their lives to prevent organ rejection and infections, and many of the drugs come with toxic side effects.
“You would probably rather have a long run of slow rehab and have your own lungs in there than to get a transplant,” Reed said in an interview over Zoom. “But for people that are likely going to die in two years and for people who are essentially crippled by their lungs, it can be just amazing.”
Fortunately, COVID-19 vaccines supposedly offer "100% protection" against "severe" COVID-19 symptoms. Though patients with comorbiditis may still be at risk as variants like the "delta" strain continue to spread.