Perioperative benzodiazepine administration among older surgical patients

The association between midazolam premedication and postoperative delirium - a retrospective cohort study

STUDY OBJECTIVE

To evaluate the association between midazolam premedication and postoperative delirium in a large retrospective cohort of patients ≥70 years.

DESIGN

Retrospective cohort study.

SETTING

A single tertiary academic medical center.

PATIENTS

Patients ≥70 years having elective non-cardiac surgery under general anesthesia from 2020 to 2021.

INTERVENTIONS

Midazolam premedication, defined as intravenous midazolam administration prior to induction of general anesthesia.

MEASUREMENTS

The primary outcome, postoperative delirium, was a collapsed composite outcome including at least one of the following: a positive 4A's test during post-anesthesia care unit stay and/or the initial 2 postoperative days; physician or nursing records reporting new-onset confusion as captured by the CHART-DEL instrument; or a positive 3D-CAM test. The association between midazolam premedication and postoperative delirium was assessed using multivariable logistic regression, adjusting for potential confounding variables. As secondary analysis, we investigated the association between midazolam premedication and a composite of other postoperative complications. Several sensitivity analyses were performed using similar regression models.

MAIN RESULTS

In total, 1973 patients were analyzed (median age 75 years, 47% women, 50% ASA score ≥ 3, 32% high risk surgery). The overall incidence of postoperative delirium was 15.3% (302/1973). Midazolam premedication was administered to 782 (40%) patients (median [IQR] dose 2 [1,2] mg). After adjustment for potential confounding variables, midazolam premedication was not associated with increased odds of postoperative delirium, with adjusted odds ratio of 1.09 (95% confidence interval 0.82-1.45; P = 0.538). Midazolam premedication was also not associated with the composite of other postoperative complications. Furthermore, no association was found between midazolam premedication and postoperative delirium in any of the sensitivity analyses preformed.

CONCLUSIONS

Our results suggest that low doses of midazolam can be safely used to pre-medicate elective surgical patients 70 years or older before non-cardiac surgery, without significant effect on the risk of developing postoperative delirium.

Preoperative Midazolam and Patient-Centered Outcomes of Older Patients: The I-PROMOTE Randomized Clinical Trial

Importance

The effect of oral midazolam premedication on patient satisfaction in older patients undergoing surgery is unclear, despite its widespread use.

Objective

To determine the differences in global perioperative satisfaction in patients with preoperative administration of oral midazolam compared with placebo.

Design, Setting, and Participants

This double-blind, parallel-group, placebo-controlled randomized clinical trial was conducted in 9 German hospitals between October 2017 and May 2019 (last follow-up, June 24, 2019). Eligible patients aged 65 to 80 years who were scheduled for elective inpatient surgery for at least 30 minutes under general anesthesia and with planned extubation were enrolled. Data were analyzed from November 2019 to December 2020.

Interventions

Patients were randomized to receive oral midazolam, 3.75 mg (n = 309), or placebo (n = 307) 30 to 45 minutes prior to anesthesia induction.

Main Outcomes and Measures

The primary outcome was global patient satisfaction evaluated using the self-reported Evaluation du Vécu de l'Anesthésie Generale (EVAN-G) questionnaire on the first postoperative day. Key secondary outcomes included sensitivity and subgroup analyses of the primary outcome, perioperative patient vital data, adverse events, serious complications, and cognitive and functional recovery up to 30 days postoperatively.

Results

Among 616 randomized patients, 607 were included in the primary analysis. Of these, 377 (62.1%) were male, and the mean (SD) age was 71.9 (4.4) years. The mean (SD) global index of patient satisfaction did not differ between the midazolam and placebo groups (69.5 [10.7] vs 69.6 [10.8], respectively; mean difference, -0.2; 95% CI, -1.9 to 1.6; P = .85). Sensitivity (per-protocol population, multiple imputation) and subgroup analyses (anxiety, frailty, sex, and previous surgical experience) did not alter the primary results. Secondary outcomes did not differ, except for a higher proportion of patients with hypertension (systolic blood pressure ≥160 mm Hg) at anesthesia induction in the placebo group.

Conclusion and Relevance

A single low dose of oral midazolam premedication did not alter the global perioperative patient satisfaction of older patients undergoing surgery or that of patients with anxiety. These results may be affected by the low dose of oral midazolam. Further trials-including a wider population with commonplace low-dose intravenous midazolam and plasma level measurements-are needed.

Trial Registration

ClinicalTrials.gov Identifier: NCT03052660.

[Special features of the perioperative course in patients with frailty syndrome]

The demographic change with an increase in the number of geriatric patients presents major challenges for perioperative medicine. Frailty is a multimorbidity complex that incorporates a combination of various factors, such as physical weakness, slower walking speed and unwanted weight loss. It is of great importance that these patients receive an individually adapted perioperative care. This includes, among others, a preoperative examination for frailty, a structured prehabilitation according to the concept of better in, better out, the compliance with the guidelines on prevention and timely treatment of postoperative delirium as well as the continuous maintenance of the body's homeostasis. By means of these measures the risk of complications in this patient group can be reduced and the best possible postoperative results can be achieved.

Evaluation of a behavioural intervention to reduce perioperative midazolam administration to older adults

Background

Older patients commonly receive benzodiazepines during anaesthesia despite guidelines recommending avoidance. Interventions to reduce perioperative benzodiazepine use are not well studied. We hypothesized an automated electronic medical record alert targeting anaesthesia providers would reduce administration of benzodiazepines to older adults undergoing general anaesthesia.

Methods

We conducted a retrospective study of adults who underwent surgery at 5 hospitals within one US academic health system. One of the hospitals received an intervention consisting of provider education and an automated electronic medical record alert discouraging benzodiazepine administration to patients aged 70 years or older. We used difference-in-differences analysis to compare patterns of midazolam use 12-months before and after intervention at the intervention hospital, using the 4 non-intervention hospitals as contemporaneous comparators.

Results

The primary analysis sample included 20,347 cases among patients aged 70 and older. At the intervention hospital, midazolam was administered in 454/4,240 (10.7%) cases pre-alert versus 250/3,750 (6.7%) post-alert (p<0.001). At comparator hospitals, respective rates were 3,186/6,366 (50.0%) versus 2,935/5,991 (49.0%) (p=0.24). After adjustment, the intervention was associated with a 3.2 percentage point (p.p.) reduction in the percentage of cases with midazolam administration (95% CI: (-5.2, -1.1); p=0.002). Midazolam dose was unaffected (adjusted mean difference -0.01 mg, 95% CI: (-0.20, 0.18); p=0.90). In 76,735 cases among patients aged 18-69, the percentage of cases with midazolam administration decreased by 6.9 p. p. (95% CI: (-8.0, -5.7); p<0.001).

Conclusion

Provider-facing alerts in the intraoperative electronic medical record, coupled with education, can reduce midazolam administration to older patients presenting for surgery but may affect care of younger patients.

Pro-Con Debate: Judicious Benzodiazepine Administration for Preoperative Anxiolysis in Older Patients

In this Pro-Con commentary article, we discuss the risks and benefits of administering preoperative benzodiazepines to older patients to decrease preoperative anxiety. The Pro side first focuses on the critical importance of treating preoperative anxiety and that benzodiazepines are the best tool to achieve that goal. The competing argument presented by the Con side is that myriad options exist to treat preoperative anxiety without simultaneously increasing the risk for devastating complications such as postoperative delirium. Both sides call for more high-quality investigations to determine the most effective strategies for decreasing preoperative anxiety in older adults while improving outcomes and reducing morbidity.

Effect of perioperative benzodiazepine use on intraoperative awareness and postoperative delirium: a systematic review and meta-analysis of randomised controlled trials and observational studies

BACKGROUND

Benzodiazepine use is associated with delirium, and guidelines recommend avoiding them in older and critically ill patients. Their perioperative use remains common because of perceived benefits.

METHODS

We searched CENTRAL, MEDLINE, CINAHL, PsycInfo, and Web of Science from inception to June 2021. Pairs of reviewers identified randomised controlled trials and prospective observational studies comparing perioperative use of benzodiazepines with other agents or placebo in patients undergoing surgery. Two reviewers independently abstracted data, which we combined using a random-effects model. Our primary outcomes were delirium, intraoperative awareness, and mortality.

RESULTS

We included 34 randomised controlled trials (n=4354) and nine observational studies (n=3309). Observational studies were considered separately. Perioperative benzodiazepines did not increase the risk of delirium (n=1352; risk ratio [RR] 1.43; 95% confidence interval [CI]: 0.9-2.27; I2=72%; P=0.13; very low-quality evidence). Use of benzodiazepines instead of dexmedetomidine did, however, increase the risk of delirium (five studies; n=429; RR 1.83; 95% CI: 1.24-2.72; I2=13%; P=0.002). Perioperative benzodiazepine use decreased the risk of intraoperative awareness (n=2245; RR 0.26; 95% CI: 0.12-0.58; I2=35%; P=0.001; very low-quality evidence). When considering non-events, perioperative benzodiazepine use increased the probability of not having intraoperative awareness (RR 1.07; 95% CI: 1.01-1.13; I2=98%; P=0.03; very low-quality evidence). Mortality was reported by one randomised controlled trial (n=800; RR 0.90; 95% CI: 0.20-3.1; P=0.80; very low quality).

CONCLUSIONS

In this systematic review and meta-analysis, perioperative benzodiazepine use did not increase postoperative delirium and decreased intraoperative awareness. Previously observed relationships of benzodiazepine use with delirium could be explained by comparisons with dexmedetomidine.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO CRD42019128144.

ERAS Protocol Options for Perioperative Pain Management of Substance Use Disorder in the Ambulatory Surgical Setting

Even prior to the COVID-19 pandemic, rates of ambulatory surgeries and ambulatory patients presenting with substance use disorder were increasing, and the end of lockdown has further catalyzed the increasing rates of ambulatory patients presenting for surgery with substance use disorder (SUD). Certain subspecialty groups of ambulatory procedures have already established protocols to optimize early recovery after surgery (ERAS), and these groups have subsequently enjoyed improved efficiency and reduced adverse outcomes as a result. In this present investigation, we review the literature as it relates to substance use disorder patients, with a particular focus on pharmacokinetic and pharmacodynamic profiles, and their resulting impact on the acute- or chronic user ambulatory patient. The systematic literature review findings are organized and summarized. We conclude by identifying areas of opportunity for further study, specifically with the aim of developing a dedicated ERAS protocol for substance use disorder patients in the ambulatory surgery setting. - Healthcare in the USA has seen an increase in rates of both substance use disorder patients and separately in ambulatory surgery cases. - Specific perioperative protocols to optimize outcomes for patients who suffer from substance use disorder have been described in recent years. - Agents of interest like opioids, cannabis, and amphetamines are the top three most abused substances in North America. - A protocol and recommend further work should be done to integrate with concrete clinical data, in which strategies should be employed to confer benefits to patient outcomes and hospital quality metrics like those enjoyed by ERAS protocol in other settings.

Association between benzodiazepine premedication and 30-day mortality rate: A propensity-score weighted analysis of the Peri-interventional Outcome Study in the Elderly (POSE)

BACKGROUND

Recent guidelines suggest that benzodiazepine premedication should be avoided in elderly patients, though with limited supporting evidence.

OBJECTIVE

We conducted a secondary analysis of the POSE data to explore the association of premedication in patients aged 80 years or older with 30-day mortality.

DESIGN

We used propensity score methods to perform a confounder-adjusted time-to-event analysis of the association between benzodiazepine premedication and 30-day mortality of the POSE study.

SETTING

POSE was conducted as a European multicentre prospective cohort study.

PATIENTS

Adults aged 80 years or older scheduled for surgical or nonsurgical intervention under anaesthesia.

RESULTS

A total of 9497 patients were analysed. One thousand five hundred and twenty-one patients received benzodiazepine premedication, 7936 patients received no benzodiazepine premedication, 30 received clonidine and 10 had missing premedication data. Inverse propensity-score-weighted log-rank analysis did not provide unambiguous evidence for an association between benzodiazepine premedication and 30-day mortality; median [range] P = 0.048 [0.044 to 0.078], estimated 30-day mortality rates 3.21% and 4.45% in benzodiazepine-premedicated and nonbenzodiazepine-premedicated patients, respectively. Inverse propensity-score-weighted Cox regression resulted in a hazard ratio of 0.71 (95% CI 0.49 to 1.04), pointing at a possible reduction of 30-day mortality in the benzodiazepine premedication group. Sensitivity analyses, which constituted subgroup, matched-pairs, and subclassification analyses, resulted in similar findings.

CONCLUSION

This secondary analysis of the POSE data did not find evidence for an unambiguous association between benzodiazepine premedication and 30-day mortality. Point estimates indicated a reduction of 30-day mortality in benzodiazepine-premedicated patients. The results presented here might be affected by unmeasured confounding factors, which could be addressed in a randomised trial.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03152734.

Multicentre analysis of practice patterns regarding benzodiazepine use in cardiac surgery

BACKGROUND

There is controversy regarding optimal use of benzodiazepines during cardiac surgery, and it is unknown whether and to what extent there is variation in practice. We sought to describe benzodiazepine use and sources of variation during cardiac surgeries across patients, clinicians, and institutions.

METHODS

We conducted an analysis of adult cardiac surgeries across a multicentre consortium of USA academic and private hospitals from 2014 to 2019. The primary outcome was administration of a benzodiazepine from 2 h before anaesthesia start until anaesthesia end. Institutional-, clinician-, and patient-level variables were analysed via multilevel mixed-effects models.

RESULTS

Of 65 508 patients cared for by 825 anaesthesiology attending clinicians (consultants) at 33 institutions, 58 004 patients (88.5%) received benzodiazepines with a median midazolam-equivalent dose of 4.0 mg (inter-quartile range [IQR], 2.0-6.0 mg). Variation in benzodiazepine dosage administration was 54.7% attributable to institution, 14.7% to primary attending anaesthesiology clinician, and 30.5% to patient factors. The adjusted median odds ratio for two similar patients receiving a benzodiazepine was 2.68 between two randomly selected clinicians and 4.19 between two randomly selected institutions. Factors strongly associated (adjusted odds ratio, <0.75, or >1.25) with significantly decreased likelihoods of benzodiazepine administration included older age (>80 vs ≤50 yr; adjusted odds ratio=0.04; 95% CI, 0.04-0.05), university affiliation (0.08, 0.02-0.35), recent year of surgery (0.42, 0.37-0.49), and low clinician case volume (0.44, 0.25-0.75). Factors strongly associated with significantly increased likelihoods of benzodiazepine administration included cardiopulmonary bypass (2.26, 1.99-2.55), and drug use history (1.29, 1.02-1.65).

CONCLUSIONS

Two-thirds of the variation in benzodiazepine administration during cardiac surgery are associated with institutions and attending anaesthesiology clinicians (consultants). These data, showing wide variations in administration, suggest that rigorous research is needed to guide evidence-based and patient-centred benzodiazepine administration.