Impact of Sedation Practices on Mortality in COVID-19-Associated Adult Respiratory Distress Syndrome Patients: A Multicenter Retrospective Descriptive Study

Abstract

Background: Reduction in sedation exposure is an important metric in intensive care unit (ICU) patients. However, challenges arose during the coronavirus disease-2019 (COVID-19) pandemic in adhering to this practice, driven by concerns on transmission and disease severity issues. Accordingly, diverse sedation approaches emerged, although the effect on mortality has not been studied thoroughly. Methods: Retrospective cohort study in the medical ICU of seven hospitals within a major Health System in Northeast Ohio. We included all adult patients admitted with COVID-19 requiring invasive mechanical ventilation (IMV) from March 2020 to December 2021. Results: Study included 2394 COVID-19 patients requiring IMV. Across waves, sample included 55-63% male subjects, with an average age of 61-68 years (P < 0.001), Acute Physiologic and Chronic Health Evaluation (APACHE)-III score 65.8-68.9 (P = 0.37), median IMV duration 8-10 days (P = 0.14), and median ICU duration 9.8-11.6 days (P = 0.084). Propofol remained the primary sedative (84-92%; P = 0.089). Ketamine use increased from the first (9.7%) to fourth (19%) wave (P = 0.002). Midazolam use decreased from the first (27.4%) to third (9.4%) wave (P = 0.001). Dexmedetomidine use declined from 35% to 27-28% (P = 0.002) after the first wave. A multivariable regression analysis indicated clinical variables explained 34% of the variation in hospital mortality (R²). Factors associated with higher mortality included age [aOR = 1.059 (95% CI 1.049-1.069); P < 0.001], COVID-19 wave, especially fourth wave [aOR = 2.147, (95% CI 1.370-3.365); P = 0.001], and higher number of vasopressors [aOR = 31.636, (95% CI 17.603-56.856); P < 0.001]. Addition of sedative medications to a second model led to an increase in the R² by only 1.6% to 35.6% [aOR = 1 (95% CI 1-1); P > 0.05] for propofol, ketamine, and midazolam. Dexmedetomidine demonstrated a decrease in the odds of mortality [aOR = 0.96 (95% CI 0.94-0.97); P < 0.001]. Conclusion: Mortality in critical COVID-19 patients was mostly driven by illness severity, and the choice of sedation might have minimal impact when other factors are controlled.