BackgroundCOVID-19 has been a devastating pandemic with little known of its neuropsychiatric complications. Delirium is 1 of the most common neuropsychiatric syndromes among hospitalized cancer patients with incidence ranging from 25% to 40% and rates of up to 85% in the terminally ill. Data on the incidence, risk factors, duration, and outcomes of delirium in critically ill cancer patients with COVID-19 are lacking.ObjectiveTo report the incidence, riaks and outcomes of critically ill cancer patients who developed COVID-19.MethodsThis is a retrospective single-center study evaluating delirium frequency and outcomes in all critically ill cancer patients with COVID-19 admitted between March 1 and July 10, 2020. Delirium was assessed by Confusion Assessment Method for Intensive Care Unit, performed twice daily by trained intensive care unit (ICU) nursing staff. Patients were considered to have a delirium-positive day if Confusion Assessment Method for Intensive Care Unit was positive at least once per day.ResultsA total of 70 patients were evaluated. Of those 70, 53 (75.7%) were found to be positive for delirium. Patients with delirium were significantly older than patients without delirium (median age 67.5 vs 60.3 y, P = 0.013). There were no significant differences in demographic characteristics, chronic medical conditions, neuropsychiatric history, cancer type, or application of prone positioning between the 2 groups. Delirium patients were less likely to receive cancer-directed therapies (58.5% vs 88.2%, P = 0.038) but more likely to receive antipsychotics (81.1% vs 41.2%, P = 0.004), dexmedetomidine (79.3% vs 11.8%, P < 0.001), steroids (84.9% vs 58.8%, P = 0.039), and vasopressors (90.6% vs 58.8%, P = 0.006). Delirium patients were more likely to be intubated (86.8% vs 41.2%, P < 0.001), and all tracheostomies (35.9%) occurred in patients with delirium. ICU length of stay (19 vs 8 d, P < 0.001) and hospital length of stay (37 vs 12 d, P < 0.001) were significantly longer in delirium patients, but there was no statistically significant difference in hospital mortality (43.4% vs 58.8%, P = 0.403) or ICU mortality (34.0% vs 58.8%, P = 0.090).ConclusionsDelirium in critically ill cancer patients with COVID-19 was associated with less cancer-directed therapies and increased hospital and ICU length of stay. However, the presence of delirium was not associated with an increase in hospital or ICU mortality.