Written by Kara Morris
TUESDAY, November 8, 2022 (HealthDay News) — While it may take some time for COVID patients who are taken off ventilators to regain consciousness, a new study suggests that is not necessarily a bad omen.
Alternatively, this may be how the body protects the brain from oxygen deprivation as the patient begins to recover.
The researchers said clinicians should take these long recovery periods into account when determining a patient’s prognosis.
Said lead study author Dr. Nicholas Schiff, co-director of the Consortium for the Advanced Study of Brain Injury at Weill Cornell Medicine in New York City.
“In this new paper, we describe a mechanism to explain what we see in both types of patients,” he said in a Weill Cornell news release.
Schiff and colleagues first observed these delays over a decade ago in comatose cardiac arrest patients. These patients received cryotherapy to reduce brain damage caused by the loss of blood flow. A 71-year-old patient woke up after 37 days, but then recovered almost completely.
Schiff, a neurologist at New York Presbyterian/Weill Cornell Medical Center, saw a similar late awakening when COVID-19 patients were taken off ventilators.
About a quarter of patients who survived ventilation took 10 days or more to regain consciousness. That was longer if they experienced more oxygen deprivation while on a ventilator.
Evidence that patients’ brains may protect themselves during these days or weeks can be found in animals that can tolerate extended periods without oxygen.
Schiff noted that this occurs in painted turtles, which can go for up to five months without oxygen under ice in winter. They do this by activating the same inhibitory system within the brain that anesthesia targets.
“These observations may provide new insights into the mechanisms of how some types of unconscious sedation are produced, and new approaches to intensive care unit sedation and to enhance recovery from disorders of consciousness,” said study co-author Dr. Emery Brown, professor of anesthesiology at Harvard Medical School. The school.
Often, doctors may recommend withdrawal of life support devices to patients who fail to regain consciousness for an extended period. This is usually indicated for 14 days or less for patients with heart disease. There are no guidelines for COVID-19 patients.
As long as patients do not have a traumatic brain injury, the researchers said, clinicians should avoid setting negative expectations about their ability to recover.
The results were published on November 7 in Proceedings of the National Academy of Sciences.
The US Centers for Disease Control and Prevention has more about ventilator use during the COVID-19 pandemic.
Source: Weill Cornell Medicine press release, 8 November 2022