Purpose
To ascertain the relationship among early (first 48ย h) deep sedation, time to extubation, delirium and long-term mortality.
Methods
We conducted a multicentre prospective longitudinal cohort study in 11 Malaysian hospitals including medical/surgical patients (nย =ย 259) who were sedated and ventilatedย โฅ24ย h. Patients were followed from ICU admission up to 28ย days in ICU with 4-hourly sedation and daily delirium assessments and 180-day mortality. Deep sedation was defined as Richmond Agitation Sedation Score (RASS)ย โคโ3.
Results
The cohort had a mean (SD) age of 53.1 (15.9) years and APACHE II score of 21.3 (8.2) with hospital and 180-day mortality of 82 (31.7ย %) and 110/237 (46.4ย %). Patients were followed for 2,657 ICU days and underwent 13,836 RASS assessments. Midazolam prescription was predominant compared to propofol, given to 241 (93ย %) versus 72 (28ย %) patients (Pย <ย 0.0001) for 966 (39.6ย %) versus 183 (7.5ย %) study days respectively. Deep sedation occurred in (182/257) 71ย % patients at first assessment and in 159 (61ย %) patients and 1,658 (59ย %) of all RASS assessments at 48ย h. Multivariable Cox proportional hazard regression analysis adjusting for a priori assigned covariates including sedative agents, diagnosis, age, APACHE II score, operative, elective, vasopressors and dialysis showed that early deep sedation was independently associated with longer time to extubation [hazard ratio (HR) 0.93, 95ย % confidence interval (CI) 0.89โ0.97, Pย =ย 0.003], hospital death (HR 1.11, 95ย % CI 1.05โ1.18, Pย <ย 0.001) and 180-day mortality (HR 1.09, 95ย % CI 1.04โ1.15, Pย =ย 0.002), but not time to delirium (HR 0.98, Pย =ย 0.23). Delirium occurred in 114 (44ย %) of patients.
Conclusion
Irrespective of sedative choice, early deep sedation was independently associated with delayed extubation and higher mortality, and thus was a potentially modifiable risk in interventional trials.