All critically ill, mechanically ventilated patients in the Intensive Care Unit (ICU) receive medications to relieve pain and anxiety. However, accumulation of these medications can be associated with serious complications, most notably longer time on the breathing machine and in the ICU. Two strategies have been shown to dramatically improve patient outcomes: nurse-directed protocols for giving sedation, and daily interruption of sedation. However, these strategies were not widely adopted, because of clinicians’ concerns about patient discomfort and agitation, and additional workload imposed by these strategies. Further, it was unclear which strategy was better for patients. Given that patient outcome could potentially be improved with either of these strategies, the fundamental question that arose was whether patients managed with a combination of two strategies which both reduce drug accumulation (protocolized sedation and daily interruption) would have an even better outcome than patients managed with only one of them (protocolized sedation).
Led by Sangeeta Mehta
, researchers from the CCCTG compared protocolized sedation alone, or protocolized sedation and daily interruption, in critically ill mechanically ventilated patients. The SLEAP
Trial was published in the Journal of the American Medical Association
in 2012. The SLEAP trial showed that there was no difference between the two groups in the time spent on the breathing machine, nor in the ICU. Unexpectedly, the daily interruption group received higher doses of sedatives, and the nurses taking care of these patients reported a higher workload. By demonstrating that daily sedation interruption is not advantageous if a protocol which targets minimal sedation is used in all patients, the SLEAP Trial informed sedation practice around the world.
In early 2015, the SLEAP Collaborators published two additional articles showing results from the SLEAP Trial. In an article in Critical Care Medicine
, Sangeeta Mehta and her coauthors described the incidence, risk factors and outcomes of delirium in mechanically ventilated adults. Among critically ill patients enrolled in the SLEAP trial, delirium was common, occurring in 54% of patients, with the same frequency in both groups. Delirium was associated with longer time on the breathing machine (by 6 days) and in the ICU (by 4 days). The application of physical restraints while in the ICU was most strongly associated with delirium; patient age, severity of illness, and prior alcohol or tobacco use were not associated with delirium.
In an article published in Journal of Critical Care
in April 2015, Louise Rose and the SLEAP Collaborators described the results of a survey of nurse and physician perspectives on the sedation protocol and daily sedation interruption strategies used in the SLEAP Trial. While most respondents (81%) liked both sedation strategies, more physicians than nurses liked DI (100% vs 61%). Nurses and physicians had different preferences and rationales for liking or disliking each strategy. Compared with physicians, fewer nurses liked using daily sedation interruption, citing patient discomfort and safety concerns.
In 2012, Louise Rose presented data on sleep and psychological illness of SLEAP patients after ICU discharge, at the Society of Critical Care Medicine conference in Houston, Texas. Of 63 patients evaluated at 6 months, 14% had an anxiety disorder, 7% had a mood disorder, and 13% had symptoms of posttraumatic stress disorder. On average, patients had moderate sleep impairment. In 2013, Lisa Burry presented data on the recall of ICU stay in SLEAP patients at the European Society of Intensive Care Medicine Congress in Paris, France. On days 3, 28 and 90 after ICU discharge, 28%, 26%, and 36% of patients, respectively, reported no recall of being in the ICU. 70% of patients had delusional memories 28 days after discharge, and these were not related to the sedation strategy they were managed with.
In 2014, Louise Rose presented data on factors associated with physical restraint use in patients enrolled in the SLEAP trial, at the European Society of Intensive Care Medicine Congress in Barcelona, Spain. 76% of patients had physical restraints applied, for a median of 4 days; and restraint use was similar in the two groups. Restrained patients received higher daily doses of sedatives, pain medications, and antipsychotic drugs. More restrained patients had unintentional device removal (26% vs 3%). We did not identify any patient characteristics or treatment factors that predicted restraint application.
The SLEAP Trial has provided the critical care community with a wealth of information about sedation management and critically ill patients.