A new case series describes peripheral nerve injuries associated with this type of positioning and suggests ways to minimize the potential damage.
“Physicians should remain aware of increased susceptibility to peripheral nerve damage in patients with severe COVID-19 after prone positioning, since it is surprisingly common among these patients, and should refine standard protocols accordingly to reduce that risk,” said senior author Colin Franz, MD, PhD, director of the Electrodiagnostic Laboratory, Shirley Ryan AbilityLab, Chicago.
The article was published online Sept. 4 in the British Journal of Anaesthesiology.
Unique type of nerve injury
Many patients who are admitted to the intensive care unit with COVID-19 undergo invasive mechanical ventilation because of acute respiratory distress syndrome (ARDS). Clinical guidelines recommend that such patients lie in the prone position 12-16 hours per day.
“Prone positioning for up to 16 hours is a therapy we use for patients with more severe forms of ARDS, and high-level evidence points to mortality benefit in patients with moderate to severe ARDS if [mechanical] ventilation occurs,” said study coauthor James McCauley Walter, MD, of the pulmonary division at Northwestern University, Chicago.
With a “significant number of COVID-19 patients flooding the ICU, we quickly started to prone a lot of them, but if you are in a specific position for multiple hours a day, coupled with the neurotoxic effects of the SARS-CoV-2 virus itself, you may be exposed to a unique type of nerve injury,” he said.
Dr. Walter said that the “incidence of asymmetric neuropathies seems out of proportion to what has been reported in non–COVID-19 settings, which is what caught our attention.”
Many of these patients are discharged to rehabilitation hospitals, and “what we noticed, which was unique about COVID-19 patients coming to our rehab hospital, was that, compared with other patients who had been critically ill with a long hospital stay, there was a significantly higher percentage of COVID-19 patients who had peripheral nerve damage,” Dr. Franz said.
The authors described 12 of these patients who were admitted between April 24 and June 30, 2020 (mean age, 60.3 years; range, 23-80 years). The sample included White, Black, and Hispanic individuals. Eleven of the 12 post–COVID-19 patients with peripheral nerve damage had experienced prone positioning during acute management.
The average number of days patients received mechanical ventilation was 33.6 (range, 12-62 days). The average number of proning sessions was 4.5 (range, 1-16) with an average of 81.2 hours (range, 16-252 hours) spent prone.
A major contributor
Dr. Franz suggested that prone positioning is likely not the only cause of peripheral nerve damage but “may play a big role in these patients who are vulnerable because of viral infection and the critical illness that causes damage and nerve injuries.”
“The first component of lifesaving care for the critically ill in the ICU is intravenous fluids, mechanical ventilation, steroids, and antibiotics for infection,” said Dr. Walter.
“We are trying to come up with ways to place patients in prone position in safer ways, to pay attention to pressure points and areas of injury that we have seen and try to offload them, to see if we can decrease the rate of these injuries,” he added.
The researchers’ article includes a heat map diagram as a “template for where to focus the most efforts, in terms of decreasing pressure,” Dr. Walter said.
“The nerves are accepting too much force for gravely ill COVID-19 patients to handle, so we suggest using the template to determine where extra padding might be needed, or a protocol that might include changes in positioning,” he added.
Dr. Franz described the interventions used for COVID-19 patients with prone positioning–related peripheral nerve damage. “The first step is trying to address the problems one by one, either trying to solve them through exercise or teaching new skills, new ways to compensate, beginning with basic activities, such as getting out of bed and self-care,” he said.
Long-term recovery of nerve injuries depends on how severe the injuries are. Some nerves can slowly regenerate – possibly at the rate of 1 inch per month – which can be a long process, taking between a year and 18 months.
Dr. Franz said that therapies for this condition are “extrapolated from clinical trial work” on promoting nerve regeneration after surgery using electrical stimulation to enable nerves to regrow at a faster rate.
“Regeneration is not only slow, but it may not happen completely, leaving the patient with permanent nerve damage – in fact, based on our experience and what has been reported, the percentage of patients with full recovery is only 10%,” he said.
The most common symptomatic complaint other than lack of movement or feeling is neuropathic pain, “which may require medication to take the edge off the pain,” Dr. Franz added.
Irreversible damage?
Commenting on the study, Tae Chung, MD, of the departments of physical medicine, rehabilitation, and neurology, Johns Hopkins University, Baltimore, said the study “provides one of the first and the largest description of peripheral nerve injury associated with prone positioning for management of ARDS from COVID-19.”
Dr. Chung, who was not involved in the research, noted that “various neurological complications from COVID-19 have been reported, and some of them may result in irreversible neurological damage or delay the recovery from COVID-19 infection,” so “accurate and timely diagnosis of such neurological complications is critical for rehabilitation of the COVID-19 survivors.”
The study received no funding. Dr. Franz, Dr. Walter, study coauthors, and Dr. Chung report no relevant financial relationships.
A version of this article originally appeared on Medscape.com.