By Antonella Macerollo
For April 2021, we have selected: Pun B.T. et al. Prevalence and risk factors for delirium in critically ill patients with COVID-19 (COVID-D): a multicentre cohort study. Lancet Respir Med. 2021; 9:239-250. doi: 10.1016/S2213-2600(20)30552-X.
The worldwide Covid-19 pandemic condition has brought more than 750 000 patients to require mechanical ventilation and thus at high risk of acute brain dysfunction (coma and delirium).
Our Covid-19 paper of the month is a multicentre cohort study including 2088 patients admitted to 69 adult intensive care units (ICUs), across 14 countries, which investigated the prevalence of delirium and coma and related risk factors for delirium in critically ill patients with COVID-19. Indeed, the knowledge of risk factors for acute brain dysfunction in this group of patients is the first step towards the development of strategies to mitigate delirium and associated sequelae
The inclusion criteria were age ≥18 years and admission to participating ICUs with severe acute respiratory syndrome coronavirus infection before April 28, 2020.
Exclusion criteria were: being moribund or needs of life-support measures withdrawn within 24 h of ICU admission, being prisoners, previous illness (including mental illness, neurodegenerative disorders, congenital or acquired brain damage, hepatic coma, drug overdose, suicide attempt, blindness and deafness).
The authors were able to collect data on patient demographics, delirium and coma assessments, and management strategies for a 21-day period.
Data on ventilator support, ICU length of stay and vital status were collected for a 28-day period.
Primary outcomes of the study were the prevalence of delirium and coma and associated risk factors with development of delirium the next.
Secondary outcomes were predictors of number of days alive without delirium or coma.
The median age of patients was 64 years (range: 54-71) with a median Simplified Acute Physiology Score (SAPS) II of 40 (range: 30-53). 1397 (66.9%) patients were invasively mechanically ventilated on the day of ICU admission and 1827 (87.5%) were invasively mechanical ventilated at some point during hospitalisation.
1337 (64 %) were given benzodiazepines for a median of 7 days (range: 4-12) during mechanical ventilation and 1481 (70.9 %) were given propofol for a median of 7 days (range: 4-11).
Our author of the month found that 1704 (81.6%) were comatose for a median of
10 days (range: 6-15) and 1147 (54.9%) were delirious for a median of 3 days (range: 2-6).
Interestingly, the risk factors for delirium the next day were mechanical ventilation, restraints, benzodiazepine, opioid, vasopressor infusions, antipsychotics (all p ≤ 0.04).
Family visitation (in person or virtual) was associated with a lower risk of delirium (p<0.0001).
During the 21-day study period, patients were alive without delirium or coma for a median of 5 days (range: 0-14).
At baseline, older age, higher SAPS II scores, male sex, smoking or alcohol abuse, use of vasopressors on day 1 and invasive mechanical ventilation on day 1 were independently associated with fewer days alive and free of delirium and coma (all p<0.01).
The authors recorded 601 patients (28.8 %) dead within 28 days of admission, mainly in the ICU.
Among all the cited risk factors for delirium, two might be modifiable: benzodiazepine and lack of family visitation. Therefore, this study leave open a possible scenario to reduce acute brain dysfunction in patients with critical Covid-19 infection.