Comparison of midazolam with fentanyl-midazolam combination during flexible bronchoscopy: A randomized, double-blind, placebo-controlled study

The influence of drugs used for sedation during mechanical ventilation on respiratory pattern during unassisted breathing and assisted mechanical ventilation: a physiological systematic review and meta-analysis

Background

Sedation management has a major impact on outcomes in mechanically ventilated patients, but sedation strategies do not generally consider the differential effects of different sedatives on respiration and respiratory pattern. A systematic review was undertaken to quantitatively summarize the known effects of different classes of drugs used for sedation on respiratory pattern during both spontaneous breathing and assisted mechanical ventilation.

Methods

This was a systematic review and meta-analysis conducted using Ovid MEDLINE, Embase, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials up to June 2020 to retrieve studies that measured respiratory parameters before and after the administration of opioids, benzodiazepines, intravenous and inhaled anaesthetic agents, and other hypnotic agents (PROSPERO #CRD42020190017). A random-effects meta-analytic model was employed to estimate the mean percentage change in each of the respiratory indices according to medication exposure with and without mechanical ventilation. Risk of bias was assessed using the Cochrane risk of bias assessment tools.

Findings

Fifty-one studies were included in the analysis. Risk of bias was generally deemed to be low for most studies. Respiratory rate decreased with the administration of opioids in both non-ventilated patients (18% decrease, 95% CI 12-24%) and ventilated patients (26% decrease, 95% CI 15-37%) and increased with inhaled anaesthetics in non-ventilated patients (83% increase, 95% CI 49-118%) and ventilated patients (50% increase, 28-72%). In non-ventilated patients, tidal volume decreased following administration of inhaled aesthetics (55% decrease, 95% CI 25-86%), propofol (36% decrease, 95% CI 20-52%), and benzodiazepines (28% decrease, 95% CI 17-40%); in patients receiving assisted mechanical ventilation, tidal volume was not significantly affected by sedation. Administration of other hypnotic agents was not associated with changes in respiratory rate or tidal volume.

Interpretation

Different classes of drugs used for sedation exert differential effects on respiratory pattern, and this may influence weaning and outcomes in mechanically ventilated patients.

Funding

This study did not receive any funding support.

Effect of different doses of midazolam combined with fentanyl during painless bronchoscopy in adults

OBJECTIVE

To investigate the clinical effect of different doses of midazolam combined with fentanyl during painless bronchoscopy in adult patients.

METHODS

In this retrospective study, a total of 200 patients who underwent painless bronchoscopy in The First People's Hospital of Wenling from January 2018 to January 2021 were selected as research subjects. These patients were assigned into an experimental group and a control group with 100 patients in each group. Patients from the experimental group were sedated with an intravenous infusion of 0.05 mg/kg midazolam and 0.2 μg/kg fentanyl, while patients from the control group were sedated using 0.1 mg/kg midazolam and 0.2 μg/kg fentanyl. The changes in heart rate (HR), saturation of pulse oximetry (SpO₂), systolic blood pressure (SBP), and diastolic blood pressure (DBP) before and at 10 minutes after administration were compared between the two groups. Ramsay sedation scale, RSS agitation scale, awaking time, incidence of adverse reactions, and anesthetic effects were also compared.

RESULTS

After medication, there was no significant difference in terms of HR, SBP, or DBP values between the two groups. The SpO₂ value in the experimental group was higher than that in the control group (96.93±1.10% vs. 94.78±0.83%, P<0.05). Ramsay sedation scale of patients from the experimental group after medication was (3.88±0.66), which was significantly higher than that of the control group (2.32±0.63), while RSS agitation score in the experimental group was (1.08±0.16), lower than that of the control group (2.32±0.63). The awaking time in the experimental group was shorter than that in control group (43.60±3.30 min vs. 50.19±4.45 min, P<0.05). Moreover, the incidence of mild cough or no cough in the experimental group was significantly better than in the control group (P<0.05). The overall incidence of adverse reactions in the experimental group was lower than that of the control group (5.00% vs. 13.00%, P<0.05). In addition, the anesthetic effect in the experimental group was better than that of the control group (90% vs. 80%, P<0.05).

CONCLUSION

The use of 0.05 mg/kg midazolam combined with 0.2 μg/kg fentanyl in adult painless bronchoscopy has little effect on SpO₂ levels, possesses a good sedative and anesthetic effect, and reduces the awaking time, restlessness response, and adverse reactions.

The impact of alfentanil supplementation on the sedation of bronchoscopy: A meta-analysis of randomized controlled trials

BACKGROUND

The efficacy of alfentanil supplementation for the sedation of bronchoscopy remains controversial. We conduct a systematic review and meta-analysis to explore the influence of alfentanil supplementation on the sedation during bronchoscopy.

METHODS

We search PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through December 2019 for randomized controlled trials (RCTs) assessing the effect of alfentanil supplementation versus placebo for the sedation during bronchoscopy. This meta-analysis is performed using the random-effect model.

RESULTS

Five RCTs are included in the meta-analysis. Overall, compared with control group for bronchoscopy, alfentanyl supplementation is associated with significantly reduced coughing scores (Std. MD = -0.55; 95% CI = -0.96 to -0.14; P = 0.009) and dose of propofol (Std. MD = -0.34; 95% CI = -0.64 to -0.04; P = 0.03), but reveals the increase in hypoxemia (RR = 1.56; 95% CI = 1.17 to 2.08; P = 0.002).

CONCLUSIONS

Alfentanyl supplementation benefits to reduce coughing scores and dose of propofol for bronchoscopy, but increases the incidence of hypoxemia. The use of alfentanyl supplementation for bronchoscopy should be with caution.

Effect of Bronchoscopist-Directed Sedation and Other Factors on Patient Comfort during Diagnostic Flexible Bronchoscopy

BACKGROUND

The factors affecting patient comfort during flexible bronchoscopy are not sufficiently addressed in resource-limited countries, and a need to devise strategies to improve patient experience is felt. The present study was undertaken to assess the effect of sedation and other factors on patient comfort during flexible bronchoscopy.

METHODS

A total of 374 patients, aged ≥18 years undergoing flexible bronchoscopy, were enrolled in this prospective, single-center, cross-sectional study. The baseline clinical data of sedation and nonsedation groups were recorded. Anxiety level was assessed using Visual Analog Scale (VAS). Postprocedure VAS score (primary outcome measure) assessed the discomfort related to flexible bronchoscopy. Patient-reported willingness for a repeat procedure and occurrence of adverse events were used as secondary outcome measures. Based on the median of VAS score, the study population was divided into low discomfort and high discomfort groups, and the factors affecting comfort levels in these two groups were noted.

RESULTS

Postprocedural VAS score (median (Q1, Q3)) for sedation and nonsedation groups was 20 (15, 30) and 25 (20, 40), respectively (<0.001). Willingness for a repeat procedure was significantly more in the sedation group (p=0.002). In the low and high discomfort groups, the preprocedural anxiety level (median (Q1, Q3)) was 20 (10, 25) and 30 (20, 40), respectively (p < 0.001).

CONCLUSION

Bronchoscopist-directed sedation significantly reduces patient discomfort and increases their willingness for a repeat procedure. Midazolam-fentanyl combination and lower prebronchoscopy anxiety are associated with lower discomfort levels during flexible bronchoscopy. This study is registered with the Clinical Trial Registry of India (CTRI/2018/11/016328).

Comparison of the effects of target-controlled infusion-remifentanil/midazolam and manual fentanyl/midazolam administration on patient parameters in dental procedures

Background

Moderate sedation is an integral part of dental care delivery. Target-controlled infusion (TCI) has the potential to improve patient safety and outcome. We compared the effects of using TCI to administer remifentanil/manual bolus midazolam with manual bolus fentanyl/midazolam administration on patient safety parameters, drug administration times, and patient recovery times.

Methods

In this retrospective chart review, records of patients who underwent moderate intravenous sedation over 12 months in a private dental clinic were assessed. Patient indicators (pre-, intra-, and post-procedure noninvasive systolic and diastolic blood pressure, respiration, and heart rate) were compared using independent t-test analysis. Patient recovery time, procedure length, and midazolam dosage required were also compared between the two groups.

Results

Eighty-five patient charts were included in the final analysis: 47 received TCI-remifentanil/midazolam sedation, and 38 received manual fentanyl/midazolam sedation. Among the physiological parameters, diastolic blood pressure showed slightly higher changes in the fentanyl group (P = 0.049), respiratory rate changes showed higher changes in the fentanyl group (P = 0.032), and the average EtCO₂ was slightly higher in the remifentanil group (P = 0.041). There was no significant difference in the minimum SpO₂ levels and average procedure length between the fentanyl and remifentanil TCI pump groups (P > 0.05). However, a significant difference was observed in the time required for discharge from the chair (P = 0.048), indicating that patients who received remifentanil required less time for discharge from the chair than those who received fentanyl. The dosage of midazolam used in the fentanyl group was 0.487 mg more than that in the remifentanil group; however, the difference was not significant (P > 0.05).

Conclusion

The combination of TCI administered remifentanil combined with manual administered midazolam has the potential to shorten the recovery time and reduce respiration rate changes when compared to manual administration of fentanyl/midazolam. This is possibly due to either the lower midazolam dosage required with TCI remifentanil administration or achieving a stable, steady-state low dose remifentanil concentration for the duration of the procedure.

Dexmedetomidine combined with midazolam infusion guided by bispectral index during bronchoscopy

BACKGROUND

Conscious sedation guided by bispectral index (BIS) during bronchoscopy has been proved to be a feasible approach. This study aimed to investigate the safety and efficacy of dexmedetomidine combined with midazolam for undergoing conscious sedation during bronchoscopy.

METHODS

The trial was registered prior to patient enrollment at the Chinese Clinical Trial Registry. Patients were randomized into DEX group (dexmedetomidine combined with midazolam) and FEN group (fentanyl combined with midazolam). Bronchoscopy was performed under awake sedation titrated to a BIS level of 60-80. The primary endpoint was the incidence of hypoxia, the secondary endpoint was the incidence of bradycardia and hypotension, effect of sedation including satisfaction degree (VAS) of the operators and patients and patients' willingness to undergo bronchoscopy again.

RESULTS

A total of 222 cases in DEX group and 211 cases in FEN group completed the study. The incidence of hypoxia and tachycardia in DEX group was lower than that in FEN group (8.1% vs 14.7%, 10.4% vs 19.0%, p < 0.05), and the incidence of hypotension and bradycardia in DEX group was higher than that in FEN group (6.8% vs 0, 15.3% vs 8.1%, p < 0.05). Midazolam dosage was significantly lower in the DEX group than in the FEN group, and the duration of surgery was significantly longer in the DEX group. The differences in intraoperative discomfort of VAS score, satisfaction VAS score, and willingness rate to undergo bronchoscopy again were not statistically significant between the two groups. In addition, the proportion of "procedural interference by patient movement" in DEX group was higher than that in FEN group.

CONCLUSIONS

The conscious sedation regimen of dexmedetomidine combined with midazolam monitored by BIS is considered to be safe and effective during bronchoscopy. The occurrence of hypoxia and tachycardia was less, and the fluctuation of blood pressure and heart rate was mild, but the proportion of bradycardia in dexmedetomidine group was higher than that in fentanyl combined with midazolam group.

Impact of concurrent remifentanil on the sedative effects of remimazolam, midazolam and propofol in cynomolgus monkeys

Drug-drug interactions can substantially change pharmacological effects of the individual substances involved. For the use of sedatives or anaesthetics, having knowledge of the extent and characteristics of such interactions is crucial for ensuring the proper protection of patients undergoing any kind of sedation. Remimazolam is a new ultra-short acting benzodiazepine that is currently under development for intravenous use in procedural sedation and general anaesthesia. It exhibits a fast onset and fast offset which enables a more rapid recovery than currently available drugs in that class, such as midazolam. The purpose of this study was to more closely investigate the sedative properties and pharmacodynamic drug-drug interaction potential of remimazolam with the opioid analgesic remifentanil and compare it with other commonly used sedatives - midazolam and propofol. For this purpose, six Cynomolgus monkeys received escalating doses of remimazolam, propofol, and midazolam intravenously without or with concurrent remifentanil. Sedation was evaluated using a general sedation scale that included monitoring exploratory and avoidance behaviour, responses to sensory stimuli, posture and gait, and eyelid position as endpoints. Based on the results, sedative doses were calculated to allow evaluation of pharmacological drug-drug interaction with remifentanil. Remimazolam induced dose-dependent and consistent sedative effects in each endpoint tested and showed a high degree of synergism with remifentanil. Midazolam showed a comparable synergism while the interaction between propofol and remifentanil was less pronounced.

Comparison of midazolam and low-dose dexmedetomidine in flexible bronchoscopy: A prospective, randomized, double-blinded study

BACKGROUND

Dexmedetomidine is a clinically useful drug for providing sedation, but concern regarding its cardiovascular side effect profile can limit its widespread use during routine diagnostic flexible bronchoscopy (FB).

MATERIALS AND METHODS

Patients between 18 and 65 years of age, who required diagnostic FB, were screened. Eligible patients were randomized to either receive 0.5 μg/kg intravenous dexmedetomidine over 10 min or intravenous midazolam 0.035 mg/kg over 1 min. If required, rescue medication (intravenous midazolam 0.5 mg bolus) was administered. The primary outcome measure was the composite score. Other parameters observed were numerical rating scale, hemodynamic variables, oxygen saturation, number of doses of rescue medication, visual analog scale score for cough, ease of bronchoscopy, Ramsay Sedation Score, and postprocedure patient response after 24 h of bronchoscopy.

RESULTS

A total of 54 patients were enrolled, 27 in each group. Total composite score (mean ± standard deviation) in dexmedetomidine and midazolam group at nasopharynx was 7.04 ± 2.19 and 6.59 ± 1.55 (P = 0.387), respectively. The corresponding values at the level of trachea were 9.22 ± 3.69 and 8.63 ± 2.13 (P = 0.475). In the dexmedetomidine group, patient response after 24 h of bronchoscopy showed the quality of sedation to be excellent in three patients, good in 10, fair in 11, and poor in 3 and discomfort to be nil in 14, mild 7, moderate in 3, and severe in 3. The corresponding values in the midazolam group for the quality of sedation were 0, 9, 18, 0 and for discomfort 10, 16, 1, 0. Other parameters did not reveal any statistically significant difference.

CONCLUSION

Dexmedetomidine at a dose of 0.5 μg/kg may provide clinically useful conscious sedation, comparable to midazolam.