Impact of PReOperative Midazolam on OuTcome of Elderly patients (I-PROMOTE): study protocol for a multicentre randomised controlled trial

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.

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.

Neurosteroids Mediate Neuroprotection in an In Vitro Model of Hypoxic/Hypoglycaemic Excitotoxicity via δ-GABAA Receptors without Affecting Synaptic Plasticity

Neurosteroids and benzodiazepines are modulators of the GABA_A receptors, thereby causing anxiolysis. Furthermore, benzodiazepines such as midazolam are known to cause adverse side-effects on cognition upon administration. We previously found that midazolam at nanomolar concentrations (10 nM) blocked long-term potentiation (LTP). Here, we aim to study the effect of neurosteroids and their synthesis using XBD173, which is a synthetic compound that promotes neurosteroidogenesis by binding to the translocator protein 18 kDa (TSPO), since they might provide anxiolytic activity with a favourable side-effect profile. By means of electrophysiological measurements and the use of mice with targeted genetic mutations, we revealed that XBD173, a selective ligand of the translocator protein 18 kDa (TSPO), induced neurosteroidogenesis. In addition, the exogenous application of potentially synthesised neurosteroids (THDOC and allopregnanolone) did not depress hippocampal CA1-LTP, the cellular correlate of learning and memory. This phenomenon was observed at the same concentrations that neurosteroids conferred neuroprotection in a model of ischaemia-induced hippocampal excitotoxicity. In conclusion, our results indicate that TSPO ligands are promising candidates for post-ischaemic recovery exerting neuroprotection, in contrast to midazolam, without detrimental effects on synaptic plasticity.

[Perioperative anxiety and fear of death]

An important field of anesthesiology but also of psychiatry and psychotherapy, is perioperative anxiety and especially the fear of death. In this review article the most important types of anxiety in the individual phases before, during and after surgery are presented and diagnostic aspects as well as risk factors are discussed. Benzodiazepines can classically be used therapeutically here, but in recent years the preoperative anxiety-reducing effects of e.g., supporting talks, acupuncture, aroma therapy, and relaxation methods have come more into focus, because benzodiazepines promote postoperative delirium, which significantly increases morbidity and mortality. Perioperative fear of death should, however, be given greater clinical and scientific attention in order not only to have a better understanding and preoperative care of patients, but also to reduce adverse consequences during surgery and afterwards.

Epigenetic Mechanisms of Postoperative Cognitive Impairment Induced by Anesthesia and Neuroinflammation

Cognitive impairment after surgery is a common problem, affects mainly the elderly, and can be divided into postoperative delirium and postoperative cognitive dysfunction. Both phenomena are accompanied by neuroinflammation; however, the precise molecular mechanisms underlying cognitive impairment after anesthesia are not yet fully understood. Anesthesiological drugs can have a longer-term influence on protein transcription, thus, epigenetics is a possible mechanism that impacts on cognitive function. Epigenetic mechanisms may be responsible for long-lasting effects and may implicate novel therapeutic approaches. Hence, we here summarize the existing literature connecting postoperative cognitive impairment to anesthesia. It becomes clear that anesthetics alter the expression of DNA and histone modifying enzymes, which, in turn, affect epigenetic markers, such as methylation, histone acetylation and histone methylation on inflammatory genes (e.g., TNF-alpha, IL-6 or IL1 beta) and genes which are responsible for neuronal development (such as brain-derived neurotrophic factor). Neuroinflammation is generally increased after anesthesia and neuronal growth decreased. All these changes can induce cognitive impairment. The inhibition of histone deacetylase especially alleviates cognitive impairment after surgery and might be a novel therapeutic option for treatment. However, further research with human subjects is necessary because most findings are from animal models.

Patients' desires for anxiolytic premedication - an observational study in adults undergoing elective surgery

BACKGROUND

Most patients experiencing preoperative anxiety would welcome support in coping with their anxiety. Anxiolytic medication is a common way to address preoperative anxiety. However, the proportion of patients who welcome anxiolytic medication preoperatively and the preferred time of taking it have not been studied thoroughly.

METHODS

Adult patients (n = 1000) scheduled to undergo elective surgery under general anesthesia were eligible to participate in this single-center observational study. Primary outcomes were the ratio of patients desiring anxiolytic medication (no/yes/on request) and the preferred time of taking it (evening before surgery/morning of day of surgery/on call to the operating room). Secondary outcomes included associations between different measures of anxiety (i.e., anxiety level according to the Amsterdam Preoperative Anxiety and Information Scale (APAIS) and anxiety status (no/yes)) and desire for anxiolytic medication (no/yes/on request). Primary outcomes were analyzed descriptively, and secondary outcomes were analyzed using multinomial logistic regressions.

RESULTS

Three hundred fifty-six (35.6%) out of 1000 patients desired anxiolytic medication and 239 (23.9%) patients would welcome anxiolytic medication on request. In patients reporting anxiety (no/yes; n = 493), 228 (46.2%) stated a clear desire for anxiolytic medication (yes) and 142 (28.8%) considered anxiolytic medication (on request). Patients' preferences concerning the timing of premedication vary widely. In patients reporting a clear desire for anxiolytic medication (n = 356), the "morning of the day of surgery" was most frequently (n = 111, 31.2%) stated as the preferred time to get anxiolytic medication, followed by "on call to the operating room" (n = 51, 14.3%). All anxiety measures were significantly associated with desire for anxiolytic medication (p < 0.05).

CONCLUSIONS

Given the importance of preoperative anxiety to patients, patients' desire for anxiolytic medication should be considered when discussing the pros and cons of premedication. Individualized instead of standardized prescription and timing of premedication is recommended.

TRIAL REGISTRATION

German Clinical Trials Register ( DRKS 00013319 , approved 23/11/2017).

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.

Evidence-Based Practices in the Cardiac Catheterization Laboratory: A Scientific Statement From the American Heart Association

Cardiac catheterization procedures have rapidly evolved and expanded in scope and techniques over the past few decades. However, although some practices have emerged based on evidence, many traditions have persisted based on beliefs and theoretical concerns. The aim of this review is to highlight common preprocedure, intraprocedure, and postprocedure catheterization laboratory practices where evidence has accumulated over the past few decades to support or discount traditionally held practices.

Midazolam Premedication Immediately Before Surgery Is Not Associated With Early Postoperative Delirium

BACKGROUND

Postoperative delirium is common among older surgical patients and may be associated with anesthetic management during the perioperative period. The aim of this study is to assess whether intravenous midazolam, a short-acting benzodiazepine used frequently as premedication, increased the incidence of postoperative delirium.

METHODS

Analyses of existing data were conducted using a database created from 3 prospective studies in patients aged 65 years or older who underwent elective major noncardiac surgery. Postoperative delirium occurring on the first postoperative day was measured using the confusion assessment method. We assessed the association between the use or nonuse of premedication with midazolam and postoperative delirium using a χ2 test, using propensity scores to match up with 3 midazolam patients for each control patient who did not receive midazolam.

RESULTS

A total of 1266 patients were included in this study. Intravenous midazolam was administered as premedication in 909 patients (72%), and 357 patients did not receive midazolam. Those who did and did not receive midazolam significantly differed in age, Charlson comorbidity scores, preoperative cognitive status, preoperative use of benzodiazepines, type of surgery, and year of surgery. Propensity score matching for these variables and American Society of Anesthesiology physical status scores resulted in propensity score-matched samples with 1-3 patients who used midazolam (N = 749) for each patient who did not receive midazolam (N = 357). After propensity score matching, all standardized differences in preoperative patient characteristics ranged from -0.07 to 0.06, indicating good balance on baseline variables between the 2 exposure groups. No association was found between premedication with midazolam and incident delirium on the morning of the first postoperative day in the matched dataset, with odds ratio (95% confidence interval) of 0.91 (0.65-1.29), P = .67.

CONCLUSIONS

Premedication using midazolam was not associated with higher incidence of delirium on the first postoperative day in older patients undergoing major noncardiac surgery.

The pharmacotherapeutic management of postoperative delirium: an expert update

INTRODUCTION

Postoperative delirium is a common sequela in older adults in the peri-operative period leading to poor outcomes with a complex pathophysiology which has led to a variety of different pharmacologic agents employed in attempts to prevent and treat this syndrome. No pharmacologic agent has been approved to treat this disorder, but this review discusses the pharmacologic strategies which have been tried based on the hypotheses of the causation of the syndrome including neurotransmitter imbalance, inflammation, and oxidative stress.

AREAS COVERED

Systematic reviews and meta-analyses of randomized clinical trials (RCTs) were included via search of electronic databases specifically for the terms postoperative delirium and pharmacologic treatments. With this approach, the recurrent topics of analgesia and sedation, antipsychotics, acetylcholinesterase inhibitors (AchE-Is), inflammation, and melatonin were emphasized and provided the outline for this review.

EXPERT OPINION

Research evidence does not support any particular agent in any of the pharmacologic classes reviewed. However, there is some potential benefit with dexmedetomidine, melatonin, and the monitoring of anesthetic agents all of which need further clinical trials to validate these conclusions. Exploration of ways to improve studies and the application of novel pharmacologic agents may offer future benefit.