Strategies to reduce excessive sedation, including protocol implementation, have been shown to reduce length of stay and improve morbidity and mortality rates for critically ill patients. While intuitively appealing, the results of some clinical trials in this area have been inconsistent. In the October issue of The Journal of the American Medical Association, investigators from the SLEAP study and the Canadian Critical Care Trials Group conducted a randomized controlled study in 14 Canadian and two U.S. centers to determine if the combination of a sedation protocol and daily interruption of sedation would result in shorter duration of mechanical ventilation compared with protocolized sedation alone.

Four hundred twenty-three patients were randomized either to protocolized sedation alone (control group) or protocolized sedation plus daily interruption of sedation (experimental group). None of the participants or study personnel was blinded. The two groups were similar in terms of baseline characteristics, and patients from surgical and trauma intensive care units (ICUs) were included. The primary outcome was time to successful extubation. Patients were analyzed according to the intention-to-treat principle, and a Cox proportional hazards model was used to estimate a hazard ratio for median time to extubation.

When adjusted for severity, age and other patient characteristics, median time to extubation was similar in both groups (hazard ratio, 1.04; 95% confidence interval, 0.83-1.31). Patients in the experimental group had significantly higher mean daily benzodiazepine doses (P=0.04) and higher daily opioid doses (1780 vs. 1070 μg/day fentanyl equivalents; P<0.001). Secondary outcomes, such as ICU mortality, hospital days and ICU-acquired organ failures, were not significantly different between the two groups. There were no significant differences when medical patients were analyzed separately from surgical and trauma patients.

The results from this study confirmed the alternative hypothesis that a combination of both interruption and protocolization for sedation was no better than protocolized sedation alone. Potential limitations of this work include lack of adherence with daily interruption in more than one-quarter of randomized patients, lack of blinding of the investigators, and absence of the use of shorter acting sedatives — such as propofol and dexmedetomidine. Nevertheless, this study was conducted with a pragmatic design, incorporating existing ICU bedside assignments that utilized clinicians rather than research staff, and included a broad mix of patients. The results suggest that daily interruption may increase — not decrease — the amount of analgesics and sedatives required for critically ill patients, while also increasing staff workload. Protocolized sedation alone may be sufficient for impacting the outcomes of interest in patients with a significant requirement for analgesia and sedation in the ICU.

Concise Critical Appraisal is a regular feature authored by SCCM member Samuel M. Galvagno Jr., DO, PhD. Each installment highlights journal articles most relevant to the critical care practitioner.