Sedation in the ICU: association between dexmedetomidine and 28-day mortality in patients with COVID-19

ABSTRACT

Introduction: The aim of our study is to evaluate the relationship between dexmedetomidine (DEX) use as a sedative agent in mechanical ventilated ICU patients and 28-day mortality. DEX, a selective alfa-2 adrenergic receptor agonist, widely used for its sedative and analgesic properties, has been linked to increasing parasympathetic tone, reducing the inflammatory response and oxidative stress [1]. Since severe COVID-19 is associated with an hyperinflammatory state, it is hypothesized that DEX might improve outcomes in these patients. Method(s) This is a retrospective observational study of mechanically ventilated patients admitted with COVID-19 pneumonia in the ICU of a tertiary center in Portugal, between March 2020 and December 2021. Logistic regression analysis was performed to evaluate the association of DEX use and 28-day mortality from time of intubation. Result(s) A total of 277 patients were analyzed, 151 in the DEX group and 126 in the no DEX group. Patients in the DEX group were younger (53.3 vs. 63.3 years, p < 0.001), had less comorbidities (2.8 vs. 3.5, p = 0.01), lower SOFA at admission (6.2 vs. 7.1, p = 0.01) but had a prolonged ICU stay (21.4 vs. 15.9, p < 0.001). Male gender (65.6 vs. 69.0, p = 0.54), incidence of obesity (56.3 vs. 46.8, p = 0.12), coronary artery disease (4.0 vs. 7.9, p = 0.16) and atrial fibrillation (4.0 vs. 7.1, p = 0.25) were similar between groups. PaO2/ FiO2 ratio at admission (111.1 vs. 108.1, p = 0.61), days spent in RASS < 3 (13.7 vs. 12.4, p = 0.31) and opioid use (14.8 vs. 13.1, p = 0.16) were also similar. From time of intubation, 28-day mortality in the cohort receiving DEX was 14.7% compared to 59.5% in the no DEX group (OR 0.12;95% CI 0.07-0.21;p = 0.01). Conclusion(s) Use of DEX was associated with lower 28-day mortality in COVID-19 critically ill patients requiring invasive mechanical ventilation in our study analysis. Considering the limitations of a retrospective observational study, RCTs are needed to confirm the results.