Delirium in COVID-19 Patients: Advice for Recognition and Management

Cognitive and mental deficits are a known potential side effect of intensive care unit (ICU) stays, but in recent months, reports have begun emerging of delirium in patients hospitalized with COVID-19. While a direct cause-and-effect relationship has not been established, clinicians need to be aware of neurologic issues as both a possible presenting symptom and a sequela of treatment for the virus.

“In COVID-19 patients, high fever and severe respiratory syndrome are the main reasons for admission to the ICU, with progression into encephalopathy after a period on a ventilator,” says Cleveland Clinic neurological ICU specialist Pravin George, DO. “But some patients who have come into our unit because of weakness in extremities or small brain bleeds have only later tested positive for the virus, and that includes young people.”

Prevalence is substantial

According to Dr. George, some experts think encephalopathy should be added to the list of common presenting symptoms for COVID-19, which include fever or chills, cough, shortness of breath or difficulty breathing, and new loss of taste or smell.

“Estimates from published reports suggest that 65% to 70% of patients with COVID-19 have delirium,” says Dr. George. “In general, the biggest risk factor for it in the ICU setting is comorbidity. The more underlying medical problems a hospitalized patient has, the greater the chance they will develop delirium.”

Causation conundrum

Because delirium associated with COVID-19 resembles ICU psychosis, it is difficult to tease apart whether it is caused by the virus, treatment for it or the effects of the ICU environment. Dr. George has seen both hyperactive and hypoactive delirium in patients with the virus. “Some patients with COVID-19 are very agitated and it takes more medication than is typical to control their breathing rate,” he says. “Others, with hypoactive delirium, are noncommunicative.”

Dr. George notes that five possible etiologies have been theorized for the delirium and encephalopathy seen in COVID-19 patients:

• Hypoxic ischemic injury because of lack of oxygen to the brain
• The effect of high levels of sedation on the brain
• Strokes caused by the hypercoagulable state that the virus induces
• A breakdown in the blood-brain barrier as a result of systemic inflammation, which can cause brain inflammation and seizures
• Seizures caused by invasion of the virus into some brain tissues

Guidance on management and prevention

When it comes to management, he advocates strategies common in treatment of ICU patients: neuromonitoring, reducing ventilation as early as possible, and effectively controlling pain and breathing without overmedicating.

“Some drugs used to sedate patients on ventilators have long-acting effects on neurons and receptors, so neuromonitoring is crucial to ensure that they are dosed appropriately,” says Dr. George. “At Cleveland Clinic, we’re studying advanced imaging techniques such as transcranial Doppler for detection of blood thickening and signs of ischemia in the brain.”

No formal guidelines exist for management or prevention of COVID-19-related delirium. Dr. George suggests that clinicians focus on guidelines developed by the Society of Critical Care Medicine for improving ICU outcomes, which consist of the “ABCDEF” bundle of interventions:

• Trials of Awakening and spontaneous Breathing, with the goal of getting patients off ventilators as quickly as possible
• Coordination of spontaneous breathing trials during periods of reduced sedation and consideration of dosage reductions for sedation and analgesia as soon as feasible
• Monitoring for and management of ICU-related Delirium
• Early ambulation, even if patients are still intubated or physically impaired, which can lead to improved physical recovery and may reduce the risk of ICU delirium
• Family empowerment and engagement to help loved ones understand what is happening during the ICU stay and what to expect after discharge

“One of the things that reduces delirium in ICU patients is having family around when they wake up,” says Dr. George. “But with COVID-19, that’s not possible because of the risk of transmission. We’ve begun using iPads at the bedside to try to connect patients with their families online as much as possible.”

Above all, Dr. George stresses treating COVID-19 patients as individuals and following standard ICU protocols for their treatment. “We may have to gown up a bit more,” he says, “but awareness of infection control shouldn’t mean we provide a lower level of care; otherwise, we may start to see more cases of ICU delirium in this population.”