Assessing clinical generalizability in sedation studies of upper GI endoscopy

Etomidate versus propofol for sedation in gastrointestinal endoscopy: A systematic review and meta-analysis of outcomes

BACKGROUND

Propofol is increasingly being used for sedation in gastrointestinal endoscopy; however, owing to its side effects, an alternative drug is needed. We aimed to compare the safety, satisfaction, and efficacy outcomes of etomidate versus propofol in patients undergoing gastrointestinal endoscopy, including advanced endoscopic procedures.

METHODS

We systematically searched Embase, PubMed, Cochrane Central Register of Controlled Trials, CINAHL (via EBSCO), China National Knowledge Infrastructure, and Web of Science (1946-April 2020) databases for randomized controlled trials of gastrointestinal endoscopy (upper gastrointestinal endoscopy, colonoscopy, and advanced endoscopy) using etomidate or propofol as sedatives. We pooled odds ratios (ORs) for the safety profile and patient and anesthesiologist satisfaction using mixed-effects conditional logistic models and standardized mean differences for efficiency outcomes using random-effects models.

RESULTS

Twenty-four studies involving 3875 patients were included. Compared with propofol, etomidate resulted in significantly reduced apnea (OR: 0.22; 95% confidence interval [CI]: 0.13-0.37; P < .001), hypoxemia (OR: 0.43; 95% CI: 0.35-0.54; P < .001), hypotension (OR: 0.20; 95% CI: 0.11-0.36; P < .001), and bradycardia (OR: 0.52; 95% CI: 0.30-0.91; P = .02) but led to increased myoclonus (OR: 8.54; 95% CI: 5.20-14.01; P < .001) and lowered anesthesiologist satisfaction (OR: 0.60; 95% CI: 0.39-0.91; P = .02).

CONCLUSION

Etomidate may be a good alternative to propofol for gastrointestinal endoscopy, especially advanced endoscopy. Etomidate appears to be safe as an inducer for hemodynamically unstable patients or older adult patients undergoing gastrointestinal endoscopy.

Identification of tools used to assess the external validity of randomized controlled trials in reviews: a systematic review of measurement properties

Background

Internal and external validity are the most relevant components when critically appraising randomized controlled trials (RCTs) for systematic reviews. However, there is no gold standard to assess external validity. This might be related to the heterogeneity of the terminology as well as to unclear evidence of the measurement properties of available tools. The aim of this review was to identify tools to assess the external validity of RCTs. It was further, to evaluate the quality of identified tools and to recommend the use of individual tools to assess the external validity of RCTs in future systematic reviews.

Methods

A two-phase systematic literature search was performed in four databases: PubMed, Scopus, PsycINFO via OVID, and CINAHL via EBSCO. First, tools to assess the external validity of RCTs were identified. Second, studies investigating the measurement properties of these tools were selected. The measurement properties of each included tool were appraised using an adapted version of the COnsensus based Standards for the selection of health Measurement INstruments (COSMIN) guidelines.

Results

38 publications reporting on the development or validation of 28 included tools were included. For 61% (17/28) of the included tools, there was no evidence for measurement properties. For the remaining tools, reliability was the most frequently assessed property. Reliability was judged as “sufficient” for three tools (very low certainty of evidence). Content validity was rated as “sufficient” for one tool (moderate certainty of evidence).

Conclusions

Based on these results, no available tool can be fully recommended to assess the external validity of RCTs in systematic reviews. Several steps are required to overcome the identified difficulties to either adapt and validate available tools or to develop a better suitable tool.

Trial registration

Prospective registration at Open Science Framework (OSF): 10.17605/OSF.IO/PTG4D.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01561-5.

Using Etomidate and Midazolam for Screening Colonoscopies Results in More Stable Hemodynamic Responses in Patients of All Ages

Background/Aims

Recent studies have demonstrated that etomidate is a safe sedative drug with noninferior sedative effects. In our recent study, we revealed that etomidate/midazolam was more hemodynamically stable than propofol/midazolam in elderly patients undergoing colonoscopies. We aimed to investigate whether compared with propofol/midazolam, etomidate/midazolam causes fewer cardiopulmonary adverse events with noninferior efficacy for screening colonoscopies in patients of all ages.

Methods

In this single-center, randomized, double-blind study, we prospectively enrolled 200 patients. The patients were divided into etomidate and propofol groups. The primary outcome was the occurrence of cardiopulmonary adverse events. The secondary outcomes were the proportion of patients with fluctuations in vital signs (oxygen desaturation and transient hypotension), adverse events interrupting the procedure, and sedation-related outcomes.

Results

Adverse cardiopulmonary events were more common in the propofol group than the etomidate group (65.0% vs 51.0%, respectively; p=0.045). Forty-six patients (46.0%) in the propofol group and 29 (29.0%) in the etomidate group experienced fluctuations in their vital signs (p=0.013). The proportions of patients experiencing adverse events that interrupted the procedure, including myoclonus, were not significantly different between the two groups (etomidate: 20.0% vs propofol: 11.0%; p=0.079). Both groups had similar sedation-related outcomes. Multivariate analysis revealed that compared with the propofol groups, the etomidate group had a significantly lower risk of fluctuations in vital signs (odds ratio, 0.427; 95% confidence interval, 0.230 to 0.792; p=0.007).

Conclusions

Compared with using propofol/midazolam, using etomidate/midazolam for screening colonoscopies results in more stable hemodynamic responses in patients of all ages; therefore, we recommend using etomidate/midazolam for colonoscopies in patients with cardiovascular risk factors.

Efficacy and Safety of Etomidate in Comparison with Propofol or Midazolam as Sedative for Upper Gastrointestinal Endoscopy

BACKGROUND/AIMS

In this study, we compared the efficacy and safety of etomidate with those of propofol or midazolam for the maintenance of sedation during endoscopy.

METHODS

The study enrolled patients who underwent sedative endoscopy in our hospital and divided them into three groups. Patients in each group were administered midazolam as induction therapy and were subsequently administered either midazolam (M + M group), propofol (M + P group), or etomidate (M + E group) as maintenance medication. The primary outcome was overall cardiovascular and respiratory adverse events.

RESULTS

In total, 105 patients who underwent sedative endoscopic examination were enrolled. The outcomes related to the procedure and sedation were not significantly different among the groups. Overall cardiovascular and respiratory adverse events were observed in 9 patients (25.7%) in the M + M group, 8 patients (23.5%) in the M + P group, and 10 patients (27.8%) in the M + E group. The logistic regression analysis revealed that etomidate use was not an independent risk factor for overall cardiovascular and respiratory adverse events.

CONCLUSION

The outcomes following the use of etomidate for maintenance after induction with midazolam for sedation in upper gastrointestinal endoscopy were not inferior to those following midazolam or propofol use from the perspectives of safety and efficacy.

Efficacy and safety of etomidate-midazolam for screening colonoscopy in the elderly: A prospective double-blinded randomized controlled study

BACKGROUND AND AIMS

Recent studies have shown that etomidate is associated with fewer serious adverse events than propofol and has a noninferior sedative effect. We investigated whether etomidate-midazolam is associated with fewer cardiopulmonary adverse events and has noninferior efficacy compared to propofol-midazolam for screening colonoscopy in the elderly.

METHODS

A prospective, single-center, double-blinded, randomized controlled trial was performed. Patients aged over 65 years who were scheduled to undergo screening colonoscopy were randomized to receive either etomidate or propofol based on midazolam. The primary outcome was all cardiopulmonary adverse events. The secondary outcomes were vital sign fluctuation (VSF), adverse events disturbing the procedure, and sedation-related outcomes.

RESULTS

The incidence of cardiopulmonary adverse events was higher in the propofol group (72.6%) than in the etomidate group (54.8%) (P = .040). VSF was detected in 17 (27.4%) and 31 (50.0%) patients in the etomidate and propofol groups, respectively (P = .010). The incidence rate of adverse events disturbing the procedure was significantly higher in the etomidate group (25.8%) than in the propofol group (8.1%) (P = .008). Moreover, the incidence rate of myoclonus was significantly higher in the etomidate group (16.1%) than in the propofol group (1.6%) (P = .004). There was no statistical significance between the 2 groups with respect to sedation times and sedation-related outcomes including patients' and endoscopist's satisfaction. In the multivariate analysis, the etomidate group had significantly low odds ratio (OR) associated with VSF (OR: 0.407, confidence interval: 0.179-0.926, P = .032).

CONCLUSIONS

We recommend using etomidate-midazolam in patients with high ASA score or vulnerable to risk factors; propofol-midazolam may be used as a guideline in patients with low ASA score.

Safer sedation practice may not translate into improvements in endoscopic outcomes

INTRODUCTION

Although the literature surrounding sedation practice and endoscopic outcomes remains sparse and controversial, there have been a number of stringent guidelines issued regarding sedation use in endoscopy.

AIMS

To assess the impact of changes to enhance safer sedation practice on endoscopic outcomes.

METHODS

Sedation practice was audited in 7234 consecutive gastrointestinal endoscopic procedures in 2004 and protocols for enhancing safer sedation practice were introduced. These included; introduction of a unit sedation policy, exchange of midazolam 10 mg vials to 5 mg repacked syringes, adverse events recording of midazolam use of greater than 5 mg and reversal agents, more stringent patient monitoring procedures and endoscopists education and feedback. A reaudit of 7071 procedures was performed in 2006. Outcomes audited the included midazolam doses, patient intolerance, 30-day postprocedure mortality, reversal agent use and total adverse events.

RESULTS

Sedation doses were reduced substantially after intervention [mean midazolam dose (SD): 4.9 mg (2.5) in 2004 vs. 2.9 mg (1.2) in 2006; P<0.0001] with no endoscopist using a mean greater than 5 mg in 2006 compared with 19% in 2004 (P=0.005). The use of reversal agents (0.6 vs. 0.7% for 2004 and 2006, respectively; P=0.74), mortality (1.0 vs. 1.3%; P=0.23) and the adverse events (1.7 vs. 2%; P=0.44) were similar. Unsuccessful procedures because of patient intolerance increased from 0.1 to 1.9% (P<0.0001).

CONCLUSION

Although protocols to enhance safer sedation practice substantially reduced sedation doses used; this did not, however, translate into improved endoscopic outcomes. Moreover, incomplete procedures because of poor tolerance increased.

Outcomes of patients who participate in randomized controlled trials compared to similar patients receiving similar interventions who do not participate

BACKGROUND

Some people believe that patients who take part in randomised controlled trials (RCTs) face risks that they would not face if they opted for non-trial treatment. Others think that trial participation is beneficial and the best way to ensure access to the most up-to-date physicians and treatments. This is an updated version of the original Cochrane review published in Issue 1, 2005.

OBJECTIVES

To assess the effects of patient participation in RCTs ('trial effects') independent both of the effects of the clinical treatments being compared ('treatment effects') and any differences between patients who participated in RCTs and those who did not. We aimed to compare similar patients receiving similar treatment inside and outside of RCTs.

SEARCH STRATEGY

In March 2007, we searched The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, The Cochrane Methodology Register, SciSearch and PsycINFO for potentially relevant studies. Our search yielded 7586 new references. In addition, we reviewed the reference lists of relevant articles.

SELECTION CRITERIA

Randomized studies and cohort studies with data on clinical outcomes of RCT participants and similar patients who received similar treatment outside of RCTs.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed studies for inclusion, assessed study quality and extracted data.

MAIN RESULTS

We identified 30 new non-randomized cohort studies (45 comparisons): no new RCTs were found. This update now includes five RCTs (yielding 6 comparisons) and 80 non-randomized cohort studies (130 comparisons), with 86,640 patients treated in RCTs and 57,205 patients treated outside RCTs. In the randomised studies, patients were invited to participate in an RCT or not; these comparisons provided limited information because of small sample sizes (a total of 412 patients) and the nature of the questions they addressed. When the results of RCTs and non-randomized cohorts that reported dichotomous outcomes were combined, there were 98 comparisons; there was also heterogeneity (P < 0.00001, I(2) = 42.2%) between studies. No statistical significant differences were found for 85 of the 98 comparisons. Eight comparisons reported statistically significant better outcomes for patients treated within RCTs, and five comparisons reported statistically significant worse outcomes for patients treated within RCTs. There was significant heterogeneity (P < 0.00001, I(2) = 58.2%) among the 38 continuous outcome comparisons. No statistically significant differences were found for 30 of the 38 comparisons. Three comparisons reported statistically significant better outcomes for patients treated within RCTs, and five comparisons reported statistically significant worse outcomes for patients treated within RCTs.

AUTHORS' CONCLUSIONS

This review indicates that participation in RCTs is associated with similar outcomes to receiving the same treatment outside RCTs. These results challenge the assertion that the results of RCTs are not applicable to usual practice.