[Skip to Content]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address 18.204.2.53. Please contact the publisher to request reinstatement.
[Skip to Content Landing]
Original Investigation
November 2018

Effect of Depth of Sedation in Older Patients Undergoing Hip Fracture Repair on Postoperative Delirium: The STRIDE Randomized Clinical Trial

Author Affiliations
  • 1Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Bayview Medical Center, Baltimore, Maryland
  • 2Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
  • 3Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Hospital, Baltimore, Maryland
  • 4Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, Maryland
  • 5Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, J. V. Brady Behavioral Biology Research Center, Johns Hopkins Bayview Campus, Baltimore, Maryland
  • 6Division of Geriatric Medicine and Gerontology, Psychiatry and Behavioral Sciences & Neuropathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
  • 7Department of Orthopedic Surgery, University of Arkansas for Medical Sciences. Little Rock
  • 8Johns Hopkins University School of Medicine, Johns Hopkins Bayview Medical Center, Baltimore, Maryland
  • 9Adult and Trauma Surgery, Department of Orthopaedic Surgery, Johns Hopkins Bayview Medical Center, Baltimore, Maryland
  • 10Center for Clinical Trials and Evidence Synthesis, Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
  • 11Departments of Medicine (General Internal Medicine), Biostatistics, and Epidemiology, and Welch Center for Prevention, Epidemiology, and Clinical Research, The Johns Hopkins University, Baltimore, Maryland
JAMA Surg. 2018;153(11):987-995. doi:10.1001/jamasurg.2018.2602
Key Points

Question  Does limiting sedation levels during hip fracture repair under spinal anesthesia reduce postoperative delirium overall or when stratified by baseline comorbidity?

Findings  In this randomized clinical trial that included 200 older patients randomized to receive lighter vs heavier sedation, limiting levels of sedation provided no significant overall benefit in reducing incident delirium. However, in a prespecified subgroup analysis, heavier vs lighter sedation levels doubled the risk of postoperative delirium in patients with low baseline comorbidities as defined by a Charlson comorbidity index score of 0.

Meaning  Limiting intraoperative sedation levels may reduce delirium in older patients with low baseline comorbidity.

Abstract

Importance  Postoperative delirium is the most common complication following major surgery in older patients. Intraoperative sedation levels are a possible modifiable risk factor for postoperative delirium.

Objective  To determine whether limiting sedation levels during spinal anesthesia reduces incident delirium overall.

Design, Setting, and Participants  This double-blind randomized clinical trial (A Strategy to Reduce the Incidence of Postoperative Delirum in Elderly Patients [STRIDE]) was conducted from November 18, 2011, to May 19, 2016, at a single academic medical center and included a consecutive sample of older patients (≥65 years) who were undergoing nonelective hip fracture repair with spinal anesthesia and propofol sedation. Patients were excluded for preoperative delirium or severe dementia. Of 538 hip fractures screened, 225 patients (41.8%) were eligible, 10 (1.9%) declined participation, 15 (2.8%) became ineligible between the time of consent and surgery, and 200 (37.2%) were randomized. The follow-up included postoperative days 1 to 5 or until hospital discharge.

Interventions  Heavier (modified observer’s assessment of sedation score of 0-2) or lighter (observer’s assessment of sedation score of 3-5) propofol sedation levels intraoperatively.

Main Outcomes and Measures  Delirium on postoperative days 1 to 5 or until hospital discharge determined via consensus panel using Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision) criteria. The incidence of delirium was compared between intervention groups with and without stratification by the Charlson comorbidity index (CCI).

Results  Of 200 participants, the mean (SD) age was 82 (8) years, 146 (73%) were women, 194 (97%) were white, and the mean (SD) CCI was 1.5 (1.8). One hundred participants each were randomized to receive lighter sedation levels or heavier sedation levels. A good separation of intraoperative sedation levels was confirmed by multiple indices. The overall incident delirium risk was 36.5% (n = 73) and 39% (n = 39) vs 34% (n = 34) in heavier and lighter sedation groups, respectively (P = .46). Intention-to-treat analyses indicated no statistically significant difference between groups in the risk of incident delirium (log-rank test χ2, 0.46; P = .46). However, in a prespecified subgroup analysis, when stratified by CCI, sedation levels did effect the delirium risk (P for interaction = .04); in low comorbid states (CCI = 0), heavier vs lighter sedation levels doubled the risk of delirium (hazard ratio, 2.3; 95% CI, 1.1- 4.9). The level of sedation did not affect delirium risk with a CCI of more than 0.

Conclusions and Relevance  In the primary analysis, limiting the level of sedation provided no significant benefit in reducing incident delirium. However, in a prespecified subgroup analysis, lighter sedation levels benefitted reducing postoperative delirium for persons with a CCI of 0.

Trial Registration  clinicaltrials.gov Identifier: NCT00590707

Limit 200 characters
Limit 25 characters
Conflicts of Interest Disclosure

Identify all potential conflicts of interest that might be relevant to your comment.

Conflicts of interest comprise financial interests, activities, and relationships within the past 3 years including but not limited to employment, affiliation, grants or funding, consultancies, honoraria or payment, speaker's bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued.

Err on the side of full disclosure.

If you have no conflicts of interest, check "No potential conflicts of interest" in the box below. The information will be posted with your response.

Not all submitted comments are published. Please see our commenting policy for details.

Limit 140 characters
Limit 3600 characters or approximately 600 words
    ×