A randomized controlled trial for the effectiveness of intraarticular versus intravenous midazolam on pain after knee arthroscopy

BACKGROUND

This double-blinded, randomized clinical trial was designed to evaluate the comparison of intravenous versus intraarticular (IA) administration of midazolam on postoperative pain after knee arthroscopy.

MATERIALS AND METHODS

In this study, 75 patients randomized in three groups to receive 75 mc/kg IA injection of midazolam and 10 ml intravenous injection of isotonic saline (Group I), 75 mc/kg intravenous injection of midazolam and 10 cc IA injection of isotonic saline (Group II) or IA and intravenous injection of isotonic saline (Group III) at the end of knee arthroscopy. Pain scores, time until the first request for analgesics, cumulative analgesic consumption, satisfaction, sedation, and complications as studied outcomes were assessed. Patients were observed for 24-h.

RESULTS

IA administration of midazolam significantly reduced pain scores in the early postoperative period compared with intravenous injection. Mean of time to first analgesic requirement in Group III (33.6 min) was significantly lower than Group II (288.8 min) and Group I (427.5 min). Cumulative analgesic consumption was increased in Groups II (35.5 mg), and III (70 mg) compared with Group I (16 mg), (P < 0.0001). Complications significantly occurred in 3 of 25 patients in Group I in contrast to 20 of 25 patients in Group III (P < 0.0001). At 2-, 4- and 8-h after arthroscopy pain score significantly decreased in Group I than other groups (P < 0.0001). Patients in Group I were significantly satisfy than other groups (P < 0.0001).

CONCLUSION

Results show the greater analgesic effect after IA administration of midazolam than after intravenous injection and hence, IA administration may be is the method of choice for pain relief after knee arthroscopy.

Comparison of dexmedetomidine/fentanyl with midazolam/fentanyl combination for sedation and analgesia during tooth extraction

Dexmedetomidine is an α2-adrenergic receptor agonist that causes minimal respiratory depression compared with alternative drugs. This study investigated whether combined dexmedetomidine/fentanyl offered better sedation and analgesia than midazolam/fentanyl in dental surgery. Sixty patients scheduled for unilateral impacted tooth extraction were randomly assigned to receive either dexmedetomidine and fentanyl (D/F) or midazolam and fentanyl (M/F). Recorded variables were patient preoperative anxiety scores, vital signs, visual analogue scale (VAS) pain scores, Observer's Assessment of Alertness/Sedation Scale (OAAS) scores after drug administration, surgeon and patient degree of satisfaction, and the duration of analgesia after surgery. The OAAS scores were significantly lower for patients administered D/F compared to those who received M/F. The duration of analgesia after the surgical procedure was significantly longer in patients who received D/F (5.3 h) than in those who received M/F (4.1 h; P=0.017). The number of surgeons satisfied with the level of sedation/analgesia provided by D/F was significantly higher than for M/F (P=0.001). Therefore, dexmedetomidine/fentanyl appears to provide better sedation, stable haemodynamics, surgeon satisfaction, and postoperative analgesia than midazolam/fentanyl during office-based unilateral impacted tooth extraction.

Different regimens of intravenous sedatives or hypnotics for electroconvulsive therapy (ECT) in adult patients with depression

BACKGROUND

Depression is a common mental disorder. It affects millions of people worldwide and is considered by the World Health Organization (WHO) to be one of the leading causes of disability. Electroconvulsive therapy (ECT) is a well-established treatment for severe depression. Intravenous anaesthetic medication is used to minimize subjective unpleasantness and adverse side effects of the induced tonic-clonic seizure. The influence of different anaesthetic medications on the successful reduction of depressive symptoms and adverse effects is unclear.

OBJECTIVES

This review evaluated the effects of different regimens of intravenous sedatives and hypnotics on anti-depression efficacy, recovery and seizure duration in depressed adults undergoing ECT.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2012, Issue 12); MEDLINE via Ovid SP (from 1966 to 31 December 2012); and EMBASE via Ovid SP (from 1966 to 31 December 2012). We handsearched related journals and applied no language restrictions.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and cross-over trials evaluating the effects of different intravenous sedatives and hypnotics for ECT. We excluded studies and trials using placebo or inhalational anaesthetics and studies that used no anaesthetic.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. When possible, data were pooled and risk ratios (RRs) and mean differences (MDs), each with 95% confidence intervals (CIs), were computed using the Cochrane Review Manager statistical package (RevMan).

MAIN RESULTS

We included in the review 18 RCTs (599 participants; published between 1994 and 2012). Most of the included trials were at high risk of bias.We analysed the results of studies comparing six different intravenous anaesthetics.Only a few studies comparing propofol with methohexital (four studies) and with thiopental (three studies) could be pooled.No difference was noted in the reduction of depression scores observed in participants treated with propofol compared with methohexital (low-quality evidence). These four studies were not designed to detect differences in depression scores.The duration of electroencephalograph (EEG) and of motor seizures was shorter in the propofol group compared with the methohexital group (low-quality evidence). No difference was seen in EEG seizure duration when propofol was compared with thiopental (low-quality evidence).Time to recovery (following commands) was longer among participants after anaesthesia with thiopental compared with propofol (low-quality evidence).For the remaining comparisons of anaesthetics, only single studies or insufficient data were available. Adverse events were inadequately reported in eligible trials, and none of the included trials reported anaesthesia-related mortality.

AUTHORS' CONCLUSIONS

Most of the included studies were at high risk of bias, and the quality of evidence was generally low. The studies were not designed to detect clinically relevant differences in depression scores. Anaesthetic agents should be chosen on the basis of adverse effect profile, emergence and how these medications affect seizure duration. If it is difficult to elicit an adequately long seizure, methohexital may be superior to propofol (low-quality evidence). If a patient is slow to recover from anaesthesia, propofol may allow a faster time to follow commands than thiopental (low-quality evidence). A factor of clinical concern that was not addressed by any study was adrenal suppression from etomidate. Optimal dosages of intravenous sedatives or hypnotics have not yet been determined.Larger well-designed randomized studies are needed to determine which intravenous anaesthetic medication leads to the greatest improvement in depression scores with minimal adverse effects.

Dexmedetomidine versus midazolam for conscious sedation in endoscopic retrograde cholangiopancreatography: An open-label randomised controlled trial

Background:

Traditionally, midazolam has been used for providing conscious sedation in endoscopic retrograde cholangiopancreatography (ERCP). Recently, dexmedetomidine has been tried, but very little evidence exists to support its use.

Objective:

The primary objective was to compare haemodynamic, respiratory and recovery profile of both drugs. Secondary objective was to compare the degree of comfort experienced by patients and the usefulness of the drug to endoscopist.

Study Design:

Open-label Randomised Controlled Trial.

Methods:

Subjects between 18 and 60 years of age with American Society of Anaesthesiologist Grade I-II requiring ERCP were enrolled in two groups (30 each). Both groups received fentanyl 1 μg/kg IV at the beginning of ERCP. Group M received IV midazolam (0.04 mg/kg) and additional 0.5 mg doses until Ramsay Sedation Scale (RSS) score reached 3-4. Group D received dexmedetomidine at loading dose of 1 μg/kg over 10 min followed by 0.5 μg/kg/h infusion until RSS reached 3-4. The vital parameters (heart rate (HR), blood pressure (BP), respiration rate, SpO₂), time to achieve RSS 3-4 and facial pain score (FPS) were compared during and after the procedure. In the recovery room, time to reach modified Aldrete score (MAS) 9-10 and patient and surgeon's satisfaction scores was also recorded and compared. Any complication during or after the procedure were also noted.

Results:

In Group D, patients had lower HR and FPS at 5, 10 and 15 min following the initiation of sedation (P<0.05). There was no statistically significant difference in BP and respiratory rate. The procedure elicited a gag response in 29 (97%) and 7 (23%) subjects in Group M and Group D respectively (P<0.05). MAS of 9-10 at 5 min during recovery was achieved in 27 (90%) subjects in Group D in contrast to 5 (17%) in Group M (P<0.05). Dexmedetomidine showed higher patient and surgeon satisfaction scores (P<0.05).

Conclusion:

Dexmedetomidine can be a superior alternative to midazolam for conscious sedation in ERCP.

Sedation during noninvasive mechanical ventilation with dexmedetomidine or midazolam: A randomized, double-blind, prospective study

BACKGROUND

Effective noninvasive mechanical ventilation (NIV) requires a patient to be comfortable and in synch with the ventilator, for which sedation is usually needed. Choice of the proper drug for sedation can lead to improved clinical outcomes.

OBJECTIVE

The aim of this study was to compare the effectiveness of dexmedetomidine and midazolam on sedation and their effects on hemodynamics and gas exchange.

METHODS

In this randomized, double-blind study, intensive care unit patients with acute respiratory failure due to acute exacerbations of chronic obstructive pulmonary disease undergoing NIV were equally randomized to receive a loading dose of 1 μg/kg IV dexmedetomidine or 0.05 μg/kg midazolam over 10 minutes followed by a maintenance infusion of 0.5 μg/kg/h dexmedetomidine (group D) or 0.1 mg/kg/h midazolam (group M). The following parameters were measured by a blinded clinician at baseline and 1, 2, 4, 6, 8, 12, and 24 hours after the loading dose was administered: Ramsay Sedation Score (RSS), Riker Sedation-Agitation Scale (RSAS), Bispectral Index (BIS), arterial blood gases, and vital signs. A second blinded investigator determined dosing changes according to the outcome of maintaining a target sedation level of RSS 2 to 3, RSAS 3 to 4, and BIS >85.

RESULTS

A total of 45 patients were assessed for enrollment in the study; 4 did not meet the inclusion criteria and 1 refused to participate (men/women 19/21; mean age 58/60; all patients were receiving bronchodilators, steroids, antibiotics, and mucolytics). In both groups (n = 20), RSS significantly increased and RSAS levels and BIS values significantly decreased after the loading dose, compared with baseline (P < 0.05). RSS levels were significantly lower beginning at 4 hours in group D compared with group M (P < 0.05). RSAS levels were not significantly different between the 2 groups in the first 8 hours. However, RSAS levels were significantly higher at 8 hours after the loading dose was administered in group D compared with group M (P < 0.01). BIS was significantly higher in group D throughout the study period (P < 0.05). Respiratory rates and gas exchange values were not significantly different between the Accepted for publication April 7, 2010. 2 groups. The number of times a change in infusion dose was needed was significantly lower in group D (2 patients with 1 change each) than in group M (3 patients with 1 change, 1 patient with 2 changes, and 3 patients with 3 changes each) (P < 0.01).

CONCLUSIONS

Dexmedetomidine and midazolam are both effective sedatives for patients with NIV. Dexmedetomidine required fewer adjustments in dosing compared with midazolam to maintain adequate sedation.

Comparison of dexmedetomidine and midazolam for monitored anesthesia care combined with tramadol via patient-controlled analgesia in endoscopic nasal surgery: A prospective, randomized, double-blind, clinical study

Abstract.

BACKGROUND

Monitored anesthesia care (MAC) may be applied for septoplasty or endoscopic sinus surgery in which an adequate sedation and analgesia without respiratory depression are desired for comfort of both the patient and the surgeon. Several combinations with different agents have been used for this purpose in these patients. However, analgesic properties for these agents have not been reported.

OBJECTIVE

The aim of this study was to investigate the analgesic and sedative effects of dexmedetomidine or midazolam infusion combined with tramadol that was used via patient-controlled analgesia (PCA), and to document the effects of these drugs on early cognitive functions.

METHODS

This prospective, randomized, double-blind, clinical study enrolled patients undergoing septoplasty or endoscopic sinus surgery at the Abant Izzet Baysal University Hospital, Bolu, Turkey, between February and September 2006. Patients were randomly allocated in a 1:1 ratio into 1 of 2 groups: the dexmedetomidine group (group D) patients received IV dexmedetomidine 1 μg/kg for 10 minutes followed by continuous infusion of 0.5 μg/kg · h(-1); and the midazolam group (group M) patients were administered a loading dose of IV midazolam 40 μg/kg for 10 minutes followed by infusion at the rate of 50 μg/kg · h(-1). A 1-minute bolus dose of IV tramadol (1.5 mg/kg) was administered in both groups 10 minutes after the administration of the primary drug, and continued via infusion using a PCA device. After baseline measurements, systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), heart rate (HR), oxygen saturation, and rate of respiration were recorded after the loading dose of study drug, after the bolus tramadol dose, at 10-minute intervals during the operation, and twice in the recovery rooms; 5 minutes after arrival and 5 minutes before discharge. Verbal rating score (VRS) and Ramsay sedation score were determined at baseline (after surgery was started), every 10 minutes thereafter until the end of the operation, and 2 times during recovery. All patients were assessed with the Wechsler Memory Scale-Revised at baseline (preoperatively) and 4 hours after the operation.

RESULTS

Seventy patients were enrolled in the study and randomly assigned to 1 of 2 groups: group D (sex, male/female, 23/12; mean [SEM] age, 32.53 [2.07] years; mean [SEM] weight, 73.03 [2.41] kg) or group M (sex, male/female, 21/14; mean [SEM] age, 34.43 [1.83] years; mean [SEM] weight, 67.90 [2.32] kg). All hemodynamic parameters (SAP, DAP, MAP, HR) were significantly higher in group M compared with group D from the onset of the surgery to discharge time (P < 0.05). Pain and sedation scores were similar in both groups, but the amount of PCA-administered rescue tramadol was significantly higher in group M (P = 0.001). A higher, though not statistically significant, prevalence of adverse events (ie, hypotension, bradycardia, and perioperative nausea and vomiting) were observed in group D. Postoperative logical verbal memory and digit span values were significantly higher in group D when compared with group M (P < 0.05). Postoperative digit span and visual reproduction scores were significantly higher than preoperative values in group D (P < 0.05). Postoperative personality functioning scores were significantly higher than preoperative values in group M (P < 0.05).

CONCLUSIONS

Based on VRS, Ramsay sedation scores, and surgeon and anesthesiologist satisfaction scores, dexmedetomidine or midazolam combined with tramadol PCA provided adequate analgesia and sedation in these adult patients undergoing septoplasty or endoscopic sinus surgery with MAC. A significantly larger amount of rescue tramadol was used by group M, suggesting that a better analgesic effect was achieved with dexmedetomidine.

Comparison of nasal Midazolam with Ketamine versus nasal Midazolam as a premedication in children

Background:

This study was done to compare effects of intranasal midazolam and intranasal midazolam with ketamine for premedication of children aged 1-12 yrs undergoing intermediate and major surgeries.

Aims:

Midazolam and Ketamine have already been used as premedicants in children. Our aim was to find out advantage of combination of midazolam with ketamine over midazolam by nasal route.

Methods:

Sixty children of age group 1-12 yrs of American Society of Anesthesiologists (ASA) grade 1 and 2 were selected. Group A- midazolam (0.2 mg/kg), Group B- midazolam (0.15 mg/kg + ketamine 1 mg/kg). Both groups received drug intranasally 30 min before surgery in recovery room with monitored anesthesia care. Onset of sedation, sedation score, emotional reaction, intravenous cannula acceptance, and mask acceptance were studied.

Statistical Analysis:

Unpaired t test and chi square test.

Results:

Sedation score, anxiolysis, attitude, reaction to intravenous cannulation, face mask acceptance, and emotional reaction were significantly better in midazolam with ketamine group. Intra operatively, in both groups, pulse rate, oxygen saturation, and respiratory rate had no significant difference; also, post operatively, no significant difference was observed in above parameters, post operative analgesia was significantly better in midazolam with ketamine group.

Conclusions:

Intra nasal premedication allows rapid and predictable sedation in children. Midazolam as well as combination of Midazolam with ketamine gives good level of sedation and comfort. But quality of sedation, analgesia, and comfort is significantly better in midazolam with ketamine group. No significant side effects were observed in both groups.

Midazolam induces apoptosis in MA-10 mouse Leydig tumor cells through caspase activation and the involvement of MAPK signaling pathway

Purpose

The present study aims to investigate how midazolam, a sedative drug for clinical use with cytotoxicity on neuronal and peripheral tissues, induced apoptosis in MA-10 mouse Leydig tumor cells.

Methods

The apoptotic effect and underlying mechanism of midazolam to MA-10 cells were investigated by flow cytometry assay and Western blotting methods.

Results

Data showed that midazolam induced the accumulation of the MA-10 cell population in the sub-G1 phase and a reduction in the G2/M phase in a time- and dose-dependent manner, suggesting an apoptotic phenomenon. Midazolam could also induce the activation of caspase-8, -9, and -3 and poly (ADP-ribose) polymerase proteins. There were no changes in the levels of Bax and cytochrome-c, whereas Bid was significantly decreased after midazolam treatment. Moreover, midazolam decreased both pAkt and Akt expression. In addition, midazolam stimulated the phosphorylation of p38 and c-Jun NH2-terminal kinase but not extracellular signal-regulated kinase.

Conclusion

Midazolam could induce MA-10 cell apoptosis through the activation of caspase cascade, the inhibition of pAkt pathway, and the induction of p38 and c-Jun NH2-terminal kinase pathways.

A clinical therapeutic protein drug-drug interaction study: coadministration of denosumab and midazolam in postmenopausal women with osteoporosis

Drug–disease interactions involving therapeutic proteins that target cytokines and potentially impact cytochrome P450 (CYP) enzymes have been of increased interest to drug regulatory agencies and industry sponsors in recent years. This parallel-group open-label study evaluated the effects of the monoclonal antibody denosumab, an inhibitor of the cytokine RANKL, on the pharmacokinetics of the probe CYP3A4 substrate midazolam in postmenopausal women with osteoporosis. The pharmacokinetics of a 2 mg oral dose of midazolam was evaluated on days 1 and 16. Subjects in Group A received a 60 mg subcutaneous dose of denosumab on day 2, 2 weeks before the second midazolam dose, while subjects in Group B did not. For Group A (n = 17), point estimates for the ratio of least square means for midazolam exposures based on maximum observed plasma concentration (C_max) and areas under the plasma concentration–time curve (AUCs) on day 16 versus day 1 ranged from 1.02 to 1.04 and 90% confidence intervals were within 0.80–1.25. No period effect was observed for Group B (n = 8). Midazolam and denosumab coadministration was safe and well tolerated. Inhibition of the cytokine RANKL by denosumab does not affect CYP3A4 in postmenopausal women with osteoporosis and will not alter the pharmacokinetics of drugs metabolized by this enzyme. These results are consistent with data suggesting that RANKL does not impact markers of inflammation and represent the first clinical data demonstrating a lack of effect on CYP3A4 of a therapeutic protein that is a cytokine modulator.

Is midazolam superior to triclofos and hydroxyzine as premedicant in children?

Background:

Search for an ideal premedicant drug for children is still on. A prospective, randomized trial was conducted to compare the efficacy of midazolam, triclofos and hydroxyzine as premedication in children undergoing lower abdominal surgeries.

Materials and Methods:

Sixty American Society of Anesthesiologists I or II patients 2-8 years of age, scheduled for elective lower abdominal surgery were included. The patients were randomly divided into three groups M, T and H of 20 children each who received midazolam 0.5 mg/kg, triclofos 75 mg/kg and hydroxyzine 0.5 mg/kg respectively, orally 60 min before surgery. The acceptability of drugs, level of sedation, anxiety during separation and on mask application was assessed.

Results:

The acceptability of midazolam and hydroxyzine was better than triclofos. Hydroxyzine was found to have lesser sedative effect as compared to both midazolam and triclofos. No major adverse effects were observed.

Conclusion:

Midazolam was found to be a better premedicant in terms of sedation, anxiolysis and safety.

Intranasal dexmedetomidine vs midazolam for premedication in children undergoing complete dental rehabilitation: a double-blinded randomized controlled trial

BACKGROUND

This prospective, randomized, double-blind study was designed to evaluate the use of intranasally administered dexmedetomidine vs intranasal midazolam as a premedication in children undergoing complete dental rehabilitation.

METHODS

Seventy-two children of American Society of Anesthesiology classification (ASA) physical status (I & II), aged 3-6 years, were randomly assigned to one of two equal groups. Group M received intranasal midazolam (0.2 mg·kg(-1)), and group D received intranasal dexmedetomidine (1 μg·kg(-1)). The patients' sedation status, mask acceptance, and hemodynamic parameters were recorded by an observer until anesthesia induction. Recovery conditions, postoperative pain, and postoperative agitation were also recorded.

RESULTS

The median onset of sedation was significantly shorter in group M 15 (10-25) min than in group D 25 (20-40) min (P = 0.001). Compared with the children in group M, those in group D were significantly more sedated when they were separated from their parents (77.8% vs 44.4%, respectively) (P = 0.002). Satisfactory compliance with mask application was 58.3% in group M vs 80.6% in group D (P = 0.035). The incidences of postoperative agitation and shivering were significantly lower in Group D compared with group M. Thirteen children (36.1%) in group M, showed signs of nasal irritation with teary eyes, and none of these signs was seen in the children in group D (P = 0.000). There were no incidences of bradycardia, hypotension, in either of the groups during study observation.

CONCLUSION

Intranasal dexmedetomidine (1 μg·kg(-1)) is an effective and safe alternative for premedication in children; it resulted in superior sedation in comparison to 0.2 mg·kg(-1) intranasal midazolam. However, it has relatively prolonged onset of action.

The role of a low-dose ketamine-midazolam regimen in the management of severe painful crisis in patients with sickle cell disease

CONTEXT

Acute pain is one of the main causes of hospital admission in sickle cell disease, with variable intensity and unpredictable onset and duration.

OBJECTIVES

We studied the role of a low-dose intravenous (IV) ketamine-midazolam combination in the management of severe painful sickle cell crisis.

METHODS

A retrospective analysis was performed with data from nine adult patients who were admitted to the intensive care unit with severe painful sickle cell crises not responding to high doses of IV morphine and other adjuvant analgesics. A ketamine-midazolam regimen was added to the ongoing opioids as an initial bolus of ketamine 0.25mg/kg, followed by infusion of 0.2-0.25mg/kg/h. A midazolam bolus of 1mg followed by infusion of 0.5-1mg/h was added to reduce ketamine emergence reactions. Reduction in morphine daily requirements and improvement in pain scores were the determinants of ketamine-midazolam effect. The t-tests were used for statistical analysis.

RESULTS

Nine patients were assessed, with mean age of 27±11 years. Morphine requirement was significantly lower after adding the IV ketamine-midazolam regimen. The mean±SD IV morphine requirement (milligram/day) in the pre-ketamine day (D0) was 145.6±16.5, and it was 112±12.2 on Day 1 (D1) of ketamine treatment (P=0.007). The Numeric Rating Scale scores on D0 ranged from eight to ten (mean 9.1), but improved to range from five to seven (mean 5.7) on D1. There was a significant improvement in pain scores after adding ketamine-midazolam regimen (P=0.01).

CONCLUSION

Low-dose ketamine-midazolam IV infusion might be effective in reducing pain and opioid requirements in patients with sickle cell disease with severe painful crisis. Further controlled studies are required to prove this effect.

Effects of dexmedetomidine and midazolam on motor coordination and analgesia: a comparative analysis

Objective

We compared the effects of 2 sedative drugs, dexmedetomidine and midazolam, on motor performance and analgesic efficacy in a rat model.

Materials and methods

Rats were randomly divided into the following 4 groups on the basis of the treatment received. The first group received 83 µg/kg/min midazolam; the second, 1 µg/kg/min dexmedetomidine; the third, 83 µg/kg/min morphine; and the fourth was a control group. The rats were measured motor coordination and pain reflexes by using rotarod, accelerod, hot plate, and tail flick tests.

Results

At all the tested speeds, the midazolam-injected rats remained on the rotarod longer than did the dexmedetomidine-injected rats. Furthermore, in the 10-minute accelerod test, the midazolam-injected rats remained for a longer duration than did the dexmedetomidine-injected rats. The latency time for the hot plate test was significantly higher at 10 minutes and 20 minutes in the dexmedetomidine group than in the midazolam group. Further, the latency time at 10 minutes for the tail flick test was greater in the dexmedetomidine group than in the midazolam group.

Conclusions

In this rat model, midazolam results in faster recovery of motor coordination performance when compared with dexmedetomidine.

The effect of ticagrelor on the metabolism of midazolam in healthy volunteers

BACKGROUND

In vitro studies have demonstrated that ticagrelor, an oral antiplatelet agent, is a substrate, activator, and inhibitor of cytochrome P450 (CYP) 3A. Thus, potential CYP3A-mediated drug-drug interactions may occur.

OBJECTIVES

The goal of this article was to report study results on the effect of ticagrelor on the pharmacokinetics of oral midazolam (oral midazolam study) and oral versus intravenous (IV) midazolam (oral/IV midazolam study). Secondary objectives included assessing the effect of midazolam on ticagrelor pharmacokinetic parameters, and the safety and tolerability of ticagrelor/midazolam coadministration.

METHODS

Two randomized crossover studies were conducted in healthy volunteers (n = 28 in each) with ticagrelor and midazolam. In the first study, volunteers received oral ticagrelor (400 mg daily) or placebo for 6 days, then oral midazolam (7.5 mg). The second study regimen was a single dose of ticagrelor 270 mg, then ticagrelor 180 mg BID for 6 days with a single oral (7.5 mg) or IV (2.5 mg) dose of midazolam.

RESULTS

After oral midazolam administration, ticagrelor significantly reduced the AUC(0-∞) of midazolam (30%-32%) and 4-hydroxymidazolam (42%-47%) but not 1-hydroxymidazolam. After administration of IV midazolam, ticagrelor reduced the AUC(0-∞) of midazolam (12%) and 4-hydroxymidazolam (23%) but not 1-hydroxymidazolam.

CONCLUSIONS

These results indicate that ticagrelor can weakly activate the metabolism of midazolam to its major 1'-hydroxy metabolite, and at the same time, seems to weakly inhibit midazolam 4'-hydroxylation. Furthermore, ticagrelor affects both hepatic and intestinal CYP3A activity.

Sedation for flexible bronchoscopy: current and emerging evidence

Flexible bronchoscopy is commonly performed by respiratory physicians and is the gold standard for directly visualising the airways, allowing for numerous diagnostic and therapeutic interventions. With the widespread use of flexible bronchoscopy and the evolution of interventional bronchoscopy with more complex and longer procedures, physicians are placing increasing importance on the use of sedation as a necessary adjunct to topical anaesthesia. There is no standardised practice for the use of sedation in bronchoscopy with a good deal of variation among physicians regarding the use of pre-procedure medication and pharmacological sedatives. In addition, there is ongoing debate and controversy about proceduralist-administered versus anaesthetist-administered sedation whilst at the same time there is a growing body of evidence that nonanaesthetist administered sedation is safe and cost-effective. In this review we summarise the evidence for the use of sedation as an adjunct to topical anaesthesia in bronchoscopy and provide the clinician with up-to-date concise guidance for the use of pharmacological sedatives in bronchoscopy and future directions for sedation in the bronchoscopy suite.

Comparison of Dexmedetomidine and Midazolam in Sedation for Percutaneous Drainage of Hepatic Hydatid Cysts

OBJECTIVE

Hydatid cyst still continues to be a public health problem. The basic treatment for the disease is surgery, but ultrasound-guided percutaneous drainage has become an important treatment alternative. Agents preferred for sedation during drainage performed under local anaesthesia must also preserve respiration and hemodynamic stability while providing adequate sedation. We compared the sedative properties of midazolam, which has a short duration of action, and a selective α2 adrenergic receptor agonist, dexmedetomidine, and the intraoperative complications.

METHODS

After approval by the clinical trials ethics committee, 40 patients with similar demographic data were randomized into two groups. All patients received 10 mg metoclopramide and 45.5 mg pheniramine before the procedure. Then, midazolam (0.07 mg kg(-1) IV bolus followed by 0.01 mg kg(-1) h(-1) infusion) was administered to Group 1, and dexmedetomidine (1 μg kg(-1) loading dose in 10 minutes, followed by 0.2 μg kg(-1) h(-1) continuous infusion) was administered to Group 2 for sedation. Just before the surgical procedure, all patients received IV propofol in a subhypnotic dose of 0.5 mg kg(-1); the dose was repeated if adequate sedation could not be achieved. Observer's assessment of alertness/sedation (OAA/S) scale and Bispectral index (BIS) were used to evaluate the sedation level during the procedure. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), peripheral oxygen saturation (SpO2) and end-tidal carbon dioxide pressure (ETCO2) were monitored before and after induction and every 5 minutes thereafter. Propofol requirement was noted for each group.

RESULTS

Sedation in the dexmedetomidine group was as effective and adequate as that observed in the midazolam group. BIS values were significantly lower in the dexmedetomidine group, especially after 10 minutes and thereafter. RR, SpO2, and ETCO2 were similar in both groups, whereas clinically insignificant decreases in HR and MAP were observed in the dexmedetomidine group. Propofol requirements were similar in both groups.

CONCLUSION

We conclude that dexmedetomidine, providing adequate sedation without respiratory depression, can be considered as an appropriate agent for sedation in surgical procedures performed under local anaesthesia.

Bispectral index score and observer's assessment of awareness/sedation score may manifest divergence during onset of sedation: Study with midazolam and propofol

Background:

Correlation between the clinical and electroencephalogram-based monitoring has been documented sporadically during the onset of sedation. Propofol and midazolam have been studied individually using the observer's assessment of awareness/sedation (OAA/S) score and Bispectral index score (BIS). The present study was designed to compare the time to onset of sedation for propofol and midazolam using both BIS and OAA/S scores, and to find out any correlation.

Methods:

A total of 46 patients (18-60 years, either sex, American Society of Anesthesiologists (ASA) I/II) posted for infraumbilical surgeries under spinal anaesthesia were randomly allocated to receive either injection propofol 1 mg/kg bolus followed by infusion 3 mg/kg/h (Group P, n=23) or injection midazolam 0.05 mg/kg bolus followed by infusion 0.06 mg/kg/h (Group M, n=23). Spinal anaesthesia was given with 2.5 ml to 3.0 ml of 0.5% bupivacaine heavy. When sensory block reached T6 level, sedation was initiated. The time to reach BIS score 70 and time to achieve OAA/S score 3 from the start of study drug were noted. OAA/S score at BIS score 70 was noted. Data from 43 patients were analyzed using SPSS 12 for Windows.

Results:

Time to reach BIS score 70 using propofol was significantly lower than using the midazolam (P<0.05). Time to achieve OAA/S score 3 using propofol was comparable with midazolam (P=0.358).

Conclusion:

A divergence exists between the time to reach BIS score 70 and time to achieve OAA/S score 3 using midazolam, compared with propofol, during the onset of sedation.

Effect of moxidectin on CYP3A4 activity as evaluated by oral midazolam pharmacokinetics in healthy subjects

In order to evaluate the potential for CYP3A4 induction by moxidectin, midazolam pharmacokinetic (PK) parameters were compared before and after moxidectin administration. Healthy subjects received a single 8 mg dose of moxidectin and 3 single 7.5 mg doses of midazolam 3 days before, and 7 and 89 days after the moxidectin. Blood samples were taken for 24 hours to measure midazolam and metabolites in plasma, and for 89 days to measure moxidectin in plasma after dose administration. Noncompartmental PK analyses were performed for each analyte. Analysis of variance was performed on log-transformed midazolam parameters with treatment day as a fixed effect. Adverse events were recorded and laboratory tests, physical examinations, pulse oximetry monitoring, vital sign measurement, and electrocardiograms performed. Thirty-nine subjects were enrolled in the study; PK data were available for 37 subjects. Moxidectin PK parameters were similar to previous studies. There were no significant changes in PK for midazolam or its metabolites 7 or 89 days after moxidectin administration. Adverse events were generally mild and there were no relevant changes in safety assessments. Thus, 8 mg moxidectin does not induce CYP3A4 activity and other CYP3A4 substrates are unlikely to be affected by moxidectin co-administration.

Effects of dexmedetomidine and xylazine on cardiovascular function during total intravenous anaesthesia with midazolam and ketamine and recovery quality and duration in horses

OBJECTIVES

To compare cardiovascular effects and recovery quality and duration of total intravenous anaesthesia (TIVA) with xylazine-ketamine-midazolam or dexmedetomidine-ketamine-midazolam.

STUDY DESIGN

Prospective, randomized experimental cross-over trial.

ANIMALS

Eight adult warmblood horses.

METHODS

After sedation with acepromazine and either xylazine [0.5 mg kg(-1) , intravenously (IV)] or dexmedetomidine (3.5 μg kg(-1) IV) anaesthesia was induced with ketamine and midazolam and maintained with a constant rate infusion (CRI) of xylazine (1 mg kg(-1)  hour(-1) ) [XKM] or dexmedetomidine (7 μg kg(-1)  hour(-1) ) [DKM] in combination with midazolam (0.1 mg kg(-1)  hour(-1) ), and ketamine infusion (initially 3 mg kg(-1)  hour(-1) ) for 120 minutes. Ketamine infusion rate was increased in response to positive reactions to electrical nociceptive stimulation performed every 30 minutes. Heart rate (HR), mean arterial blood pressure (MAP) and cardiac output (Q˙t) were measured before treatment (baseline), after sedation (not Q˙t), and during anaesthesia. Xylazine, dexmedetomidine, midazolam and ketamine kinetics were calculated, from plasma drug concentrations. Twenty minutes after end of TIVA, flumazenil (0.01 mg kg(-1) IV) was administered. Recovery quality and duration were assessed. Two-way analysis of variance with repeated measurements or Wilcoxon signed rank test as relevant were used to analyse data with an alpha of 5%.

RESULTS

Compared to baseline, MAP did not change, while similar, but limited, decreases in HR and Q˙t were observed in both TIVA's. Mean ketamine doses of 3.7 mg kg(-1)  hour(-1) were required with both treatments. Plasma concentrations of dexmedetomidine and xylazine showed high intra- and inter-individual changes with elimination half-lifes of 46 ± 7 minutes and 64 ± 13 minutes, respectively. Recovery quality was good to excellent with mean duration of 37 ± 16 and 46 ± 21 minutes after stopping TIVA with XKM and DKM, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

Both drug combinations are suitable to maintain anaesthesia for two hours, with good cardiovascular and good to excellent recovery conditions.

Prophylactic midazolam and clonidine for emergence from agitation in children after emergence from sevoflurane anesthesia: a meta-analysis

BACKGROUND

Emergence agitation (EA) after emergence from sevoflurane anesthesia is a common phenomenon in children. The efficacy of prophylactic midazolam or clonidine in preventing EA is controversial.

OBJECTIVE

We performed a meta-analysis of clinical trials of the 2 drugs to evaluate their ability to prevent EA in pediatric patients after emergence from sevoflurane anesthesia.

METHODS

A comprehensive literature search was conducted to identify clinical trials that observed the effect of midazolam and clonidine on preventing EA in children after their emergence from sevoflurane anesthesia. All data were examined using the Mantel-Haenszel model to calculate the pooled odds ratio (OR) and 95% CI. I(2) was used to assess heterogeneity. Subgroup analysis was used to assess the effects of preoperative analgesics, routes of administration, and dose, and funnel plots were used to check publication bias.

RESULTS

After a comprehensive literature search, we found 12 papers that met the criteria for inclusion in this analysis, with a total of 447 children in the midazolam group and 767 children in the clonidine group. We found that both midazolam and clonidine decreased the incidence of EA (OR = 0.45 [95% CI, 0.29-0.70], P = 0.0004, I(2) = 46%; and OR = 0.24 [95% CI, 0.13-0.43], P < 0.00001, I(2) = 48%, respectively). Subgroup analysis indicated that preoperative analgesia may decrease the effect of midazolam against EA, whereas for clonidine, neither the route of administration (intravenous or caudal) nor the dose affected the results. Funnel plots did not detect publication bias in the midazolam group, but a bias was detected in the clonidine group.

CONCLUSIONS

This meta-analysis suggests that prophylactic administration of midazolam or clonidine could significantly decrease the incidence of sevoflurane-induced EA in pediatric patients.

Comparison of biochemical stress indicators in juvenile captive estuarine crocodiles (Crocodylus porosus) following physical restraint or chemical restraint by midazolam injection

Using a prospective, randomized study design we demonstrate that midazolam sedation minimizes acidosis compared with physical restraint in captive juvenile estuarine crocodiles during handling or noninvasive procedures at preferred body temperature. A dose of midazolam (5.0 mg/kg) was administered intramuscularly into the forelimb of 20 male estuarine crocodiles weighing 2-3.5 kg. Their heart and respiratory rate and degree of sedation were monitored until recovery and then daily for 7 subsequent days. Blood samples were taken at 30, 60, 90, 180, and 360 min. We recorded lactate, partial pressure of carbon dioxide (CO2), hematocrit, glucose, and blood pH. A second group (1.9-2.6 kg) was physically restrained for 5 min and the same parameters recorded. Physically restrained animals demonstrated elevated heart rate, respiratory rate, glucose, lactate, and anion gap compared with the midazolam-treated group. Physically restrained animals had lower pH, bicarbonate, and partial pressure of CO2 compared with the midazolam-treated group. Behavior in the physically restrained group in the days following the study was disrupted, with reluctance to feed and bask, compared with midazolam-treated animals whose behavior was normal. We conclude that midazolam administered in the forelimb of captive estuarine crocodiles of 2-3.5 kg provides predictable onset and duration of sedation enabling physical examination, sample collection, and translocation of the animals with minimal disturbance to lactate, pH, and CO2. Behavior following recovery appears normal.

Midazolam induces cellular apoptosis in human cancer cells and inhibits tumor growth in xenograft mice

Midazolam is a widely used anesthetic of the benzodiazepine class that has shown cytotoxicity and apoptosisinducing activity in neuronal cells and lymphocytes. This study aims to evaluate the effect of midazolam on growth of K562 human leukemia cells and HT29 colon cancer cells. The in vivo effect of midazolam was investigated in BALB/c-nu mice bearing K562 and HT29 cells human tumor xenografts. The results show that midazolam decreased the viability of K562 and HT29 cells by inducing apoptosis and S phase cell-cycle arrest in a concentration-dependent manner. Midazolam activated caspase-9, capspase-3 and PARP indicating induction of the mitochondrial intrinsic pathway of apoptosis. Midazolam lowered mitochondrial membrane potential and increased apoptotic DNA fragmentation. Midazolam showed reactive oxygen species (ROS) scavenging activity through inhibition of NADPH oxidase 2 (Nox2) enzyme activity in K562 cells. Midazolam caused inhibition of pERK1/2 signaling which led to inhibition of the anti-apoptotic proteins Bcl-XL and XIAP and phosphorylation activation of the pro-apoptotic protein Bid. Midazolam inhibited growth of HT29 tumors in xenograft mice. Collectively our results demonstrate that midazolam caused growth inhibition of cancer cells via activation of the mitochondrial intrinsic pathway of apoptosis and inhibited HT29 tumor growth in xenograft mice. The mechanism underlying these effects of midazolam might be suppression of ROS production leading to modulation of apoptosis and growth regulatory proteins. These findings present possible clinical implications of midazolam as an anesthetic to relieve pain during in vivo anticancer drug delivery and to enhance anticancer efficacy through its ROS-scavenging and pro-apoptotic properties.

Reduced exposure variability of the CYP3A substrate simvastatin by dose individualization to CYP3A activity

This study aimed to demonstrate that the dose of a CYP3A substrate (simvastatin) can be adapted individually on the basis of CYP3A activity as assessed by midazolam metabolic clearance. In 18 healthy participants individual CYP3A activity was quantified using midazolam metabolic clearance both alone and during CYP3A inhibition with 40 mg ritonavir. Thereafter, simvastatin acid exposure was determined after a simvastatin standard dose (40 mg) and doses adapted to individual CYP3A activity at baseline and during CYP3A inhibition. Interindividual variability of CYP3A activity and simvastatin acid AUC0-24 was large and both correlated (r(2)  = 0.745, P < .001). The adapted simvastatin doses ranged from 25 to 80 mg and their administration reduced simvastatin variability fivefold. Despite the low adapted simvastatin dose of 12 mg during CYP3A inhibition with ritonavir, exposure increased (point estimate of 4.2 [90% CI: 3.15-5.61]) probably caused by additional OATP1B1 inhibition. CYP3A activity-based dose adaptation can be used to reduce interindividual variability in simvastatin exposure.

Assessing the sedative effect of oral vs submucosal meperidine in pediatric dental patients

BACKGROUND

THE GOAL OF THIS INVESTIGATION WAS TO COMPARE THE BEHAVIORAL AND PHYSIOLOGICAL EFFECTS OF THREE SEDATIVE DRUG REGIMENS: oral meperidine (OM), submucosal meperidine (SM) and oral midazolam (M) in healthy pediatric patients.

MATERIALS AND METHODS

This study sample consisted of thirty children aged 24-72 months (mean = 41.1) exhibiting definitely negative behavior. Three sedative regimens including: Oral meperidine/hydroxyzine, oral midazolam/hydroxyzine and submucosal meperidine/oral hydroxyzine were administered randomly during three consecutive appointments with a crossover design. Houpt behavioral scale was employed for evaluating the sedation effect of each regimen by a calibrated independent Pediatric dentist. Physiologic parameters were also recorded including blood oxygen saturation and pulse rate. Data was analyzed using Wilcoxon-signed ranked test, Mc-Nemar, GEE Logistic regression, Friedman, Fisher exact and Cochran tests for significance.

RESULTS

Overall success rates were 50%, 46.7% and 26.7% for submucosal meperidine, oral meperidine and oral midazolam, respectively (P = 0.03). The probability of achieving a success in behavior control was more in 48-72 month olds. Child's age and drug type were the two main predictors of altered behavior. Evaluating the differences between the effects of three tested regimens on recorded physiological parameters showed no significant differences.

CONCLUSION

All three regimens were proved safe within the limits of the current study. Meperidine sedation in both routes was considered to be more effective. Although there was less sleep and more head/oral resistance in midazolam group, the difference between groups was not significant.

Comparison of effects of ketamine, ketamine-dexmedetomidine and ketamine-midazolam on dressing changes of burn patients

Objective:

The aim of this randomized, controlled study was to compare the sedoanalgesic effects of ketamine-dexmedetomidine and ketamine-midazolam on dressing changes of burn patients.

Materials and Methods:

Following Ethics Committee approval and informed patient consent, 90 ASA physical statuses I and II adult burn patients were included in the study. Patients were randomly divided into three groups. Ten minutes before dressing change, the dexmedetomidine group (group KD) (n = 30) received a continuous infusion of dexmedetomidine at a rate of 1 μg kg^-1, the midazolam group (group KM) (n = 30) received a continuous infusion of midazolam at a rate of 0.05 mg kg^-1 and the saline group (group KS) (n = 30) received a continuous infusion of saline intravenously. One minute before dressing change, each patient was administered 1 mg kg^-1 ketamine intravenously. Hemodynamic variables, pain and sedation scores, the number of patients requiring additional ketamine, time to dressing change and recovery time were recorded.

Results:

Systolic blood pressure (SBP) values were significantly lower at, before and after ketamine administration; and 5, 10 and 15 minutes after the procedure in group KD in comparison with the other groups (P <0.05). There was no significant difference in pain scores among the groups during the study period. Sedation scores were significantly higher in group KD than in groups KM and KS at the end of the first hour (P <0.05). Time to dressing change and recovery time were similar in all the groups

Conclusion:

In burn patients undergoing dressing changes, although both combinations ketamine-dexmedetomidine and ketamine-midazolam offered an effective sedoanalgesia without causing any significant side effect, the former resulted in higher sedation and lower hemodynamic discrepancy.