A long road to recovery: Lung rehab needed after COVID-19
If one word describes Eladio (“Lad”) Braganza, age 77, it’s “tenacious.” For 28 days, he clung to life on a ventilator in a Seattle ICU. Now – after a 46-day hospitalization for SARS-CoV-2 infection – he’s making progress in inpatient rehab, determined to regain function.
“We were not sure if he was going to make it through his first night in the hospital, and for a while after that. We were really prepared that he would not survive his ventilator time,” his daughter, Maria Braganza, said in an interview just 5 days after her father had been transferred to inpatient rehab.
In many ways, Mr. Braganza’s experience is typical of seriously ill COVID-19 patients. Many go from walking and talking to being on a ventilator within 10 hours or less. Mr. Braganza was admitted to the hospital on March 21 and was intubated that day. To keep him on the ventilator, he was heavily sedated and unconscious at times. In the ICU, he experienced bouts of low blood pressure, a pattern of shock that occurs in COVID-19 patients and that does not always respond to fluids.
Doctors have quickly learned to treat these patients aggressively. Many patients in the ICU with COVID-19 develop an inflamed, atypical form of acute respiratory distress syndrome (ARDS), in which the lung’s compliance, or stiffness, does not match the severity of hypoxia. These patients require high levels of oxygen and high ventilator settings. Many develop pneumothorax, or collapsed lungs, because of the high pressures needed to deliver oxygen and the prolonged time on ventilation.
“The vast majority of COVID patients in the ICU have lung disease that is quite severe, much more severe than I have seen in my 20 years of doing this,” said critical care specialist Anna Nolan, MD, of the department of medicine at New York University.
After about 2 weeks, some of these patients can come off the ventilator, or they may undergo a tracheostomy, a hole in the neck through which a tube is placed to deliver oxygen. By this time, many have developed ICU-acquired weakness and muscle wasting. Some may be so debilitated that they cannot walk. Even the respiratory muscles that help them breathe may have weakened as a result of the ventilator doing the work for them.
These patients “get sick very fast, and it takes a long time for them to heal. What’s not really well appreciated is how much rehab and how much recovery time these patients are going to need,” said David Chong, MD. He is medical director of the ICU at New York–Presbyterian Hospital/Columbia University Medical Center, and he has been on the front lines during the COVID-19 surge in New York City.
The road to recovery
Regardless of the cause, many people who have a prolonged stint in the ICU face an even longer convalescence. Still-unanswered questions concern whether recovery time will be longer for those with COVID-19, compared with other illnesses, and whether some of the damage may be permanent. A number of small studies in Hong Kong and China, as well as studies of severe acute respiratory syndrome patients’ recoveries, have promoted speculation about possible long-lasting damage to lungs and other organs from COVID-19.
Yet some of these reports have left out important details about ARDS in COVID-19 patients who also may be most at risk for long-lasting damage. To clear up some of the confusion, the Pulmonary Fibrosis Foundation said on April 6 that some but not all of COVID-19 patients who develop ARDS may go on to develop lung fibrosis – scarring of the lungs – which may be permanent.
“Post-ARDS fibrosis typically is not progressive, but nonetheless can be severe and limiting. The recovery period for post-ARDS fibrosis is approximately 1 year and the residual deficits persist, but generally do not progress,” the foundation noted.
Emerging research on lung damage in COVID-19
Because the pandemic is only a few months in, it’s unclear as yet what the long-term consequences of severe COVID-19 may be. But emerging data are enabling researchers to venture an educated guess about what may happen in the months and years ahead.
The key to understanding the data is knowing that ARDS is a syndrome – the end product of a variety of diseases or insults to the lung. Under the microscope, lung damage from ARDS associated with COVID-19 is indistinguishable from lung damage resulting from other causes, such as vaping, sepsis, or shock caused by a motor vehicle accident, said Sanjay Mukhopadhyay, MD, director of pulmonary pathology at Cleveland Clinic.
Dr. Mukhopadhyay, who specializes in lung pathology, performed one of the first complete autopsies of a COVID-19 patient in the United States. In most autopsy series published to date, he said, the most common lung finding in patients who have died from COVID-19 is diffuse alveolar damage (DAD), a pattern of lung injury seen in ARDS from many other causes.
In DAD, the walls of the alveoli – thinly lined air sacs that facilitate gas exchange in the lung – develop a pink, hyaline membrane composed of damaged cells and plasma proteins that leak from capillaries in the wall of the alveolus. This hyaline membrane gets plastered against the wall of the alveolus and interferes with diffusion of oxygen into the body.
“We know what happens in ARDS from other causes. If you follow people who have been on a ventilator long term, some of their respiratory function goes back to normal,” Dr. Mukhopadhyay said. “But there are other people in whom some degree of respiratory impairment lingers. In these patients, we think the DAD progresses to an organizing stage.”
Organizing pneumonia refers to a family of diseases in which fibroblasts (cells involved in wound healing) arrive and form scar tissue that forms hyaline membranes and fibrin balls (tough proteins) that fill up the alveoli, making gas exchange very difficult.
Also called BOOP (bronchiolitis obliterans organizing pneumonia), this condition is sensitive to steroids. Early aggressive steroid treatment can prevent long-term lung damage. Without steroids, damage can become permanent. A variant of this condition is termed acute fibrinous and organizing pneumonia (AFOP), which is also sensitive to steroids. A report from France demonstrates AFOP in some patients who have died from COVID-19.
The trick is identifying who is developing BOOP and who is not, and beyond that, who might be most amenable to treatment. Use of steroids for patients with certain other problems, such as a bacterial infection on top of COVID-19, could be harmful. David H. Chong, MD, and colleagues at Columbia University Irving Medical Center, New York, are investigating this to determine which COVID-19 patients may benefit from early steroid therapy.
“It’s not clear if there is a predominant histologic type or if we are catching people at different phases of their disease, and therefore we’re seeing different lung pathology,” Dr. Chong said.
He thinks that many patients with severe COVID-19 probably will not develop this pattern of lung scarring. “We’re speculating that lung damage from severe COVID-19 is probably going to behave more like lung damage from regular ARDS, which is often reversible. We think the vast majority of these patients probably have DAD that is similar to most patients with ARDS from other etiologies,” Dr. Chong said.
That would be consistent with information from China. In an April interview with Chinese domestic media, Zhong Nanshan, MD, a pulmonologist at the head of China’s COVID-19 task force, stated that he expects that the lungs in most patients with COVID-19 will gradually recover. He was responding to a widely publicized small study that found evidence of residual lung abnormalities at hospital discharge in most patients (94%, 66/70) who suffered from COVID-19 pneumonia in Wuhan, China, from January to February 2020.