P.0811 Factors and outcomes associated with delirium in critically ill COVID-19 patients

ABSTRACT

Introduction: Evidence demonstrates that 25-33% of hospitalized patients with COVID-19 develop delirium [1,2], with rates up to 65% in critically ill patients [3]. Several potential reasons, including the use of deep sedation and invasive mechanical ventilation (IMV), as well as the restrictions to limit infection transmission, such as prohibition of family visits and minimal contact with health staff were identified [4]. Although factors and outcomes associated with delirium are well documented, limited data are available regarding severe COVID-19 patients. Aims: This study aims to estimate the rates of delirium in critically ill COVID-19 patients and to analyze factors that may be associated with its development, as well as to examine long-term outcomes. Methods: From March to May 2020 (in COVID-19 first wave), all adult patients (≥18y.o.) admitted due to COVID-19, in the Intensive Care Medicine Department (ICMD) of a University Hospital (CHUSJ), in Porto, Portugal, were assessed, unless they had a ICMD length of stay (LoS) ≤24h, terminal illness or major sensory loss or inability to communicate at the time of follow-up. Participants were evaluated during a scheduled telephone follow-up appointment with a comprehensive protocol, including Six-item Cognitive Impairment Test (6CIT) (cognitive impairment);Patient Health Questionnaire (PHQ-9) (symptoms of depression);General Anxiety Disorder (GAD-7) (symptoms of anxiety);and EuroQol five-dimension five-level questionnaire (EQ-5D-5L) (health-related quality of life-HRQoL), which includes EQ-Visual Analogue Scale (EQ-VAS) (global health status patient perception). Data on acute illness severity, sedative/analgesic drugs use, respiratory support and major complications (including delirium, nosocomial infections and difficulty weaning from mechanical ventilation) during ICMD stay, were obtained from hospital electronic records review. Patients with and without delirium were compared, using Mann-Whitney test for continuous variables, and Chi-square or Fisher tests for paired categorical variables (significance level of 0.05). This study is part of an ongoing larger multidisciplinary research project (MAPA-Mental Health in Critically ill patients with COVID-19). Results: The sample included 59 patients (median age=65 years;66.1% male). Delirium was registered in almost half of the sample (49.2%). Patients with delirium were significantly older (median=72 vs. 62;p=0.010) and presented more nosocomial infections (82.8% vs 53.3%;p=0.032) particularly ventilator-associated pneumonia (75.9% vs. 33.3%;p=0.003). Also, they were significantly more likely to be deeply sedated (89.7% vs 60%;p=0.021), more often required IMV (89.7% vs 60%;p=0.021). Moreover, those with delirium stayed longer in the hospital (median=67 vs 37 days;p=0.014). Concerning HRQoL, assessed at follow-up appointment, patients who have developed delirium reported more problems in self-care (48.3% vs 10%;p=0.003) and in everyday activities (79.3% vs 53.3%;p=0.035) after hospital discharge. Nevertheless, no statistically significant differences were found for cognitive impairment, symptoms of anxiety and depression. Conclusions: Delirium was common in this critically ill COVID-19 sample, namely in older patients, who have been deeply sedated, invasively ventilated or had major ICU complications. It was associated with longer hospital stay and worse HRQoL. Recognizing potential associated factors will allow the identification of high-risk patients that should be targeted for early screening with preventive interventions to minimize the adverse outcomes associated to delirium in critical COVID-19 patients. No conflict of interest