Premedication with midazolam is more effective by the sublingual than oral route

Amenamevir: Studies of Potential CYP3A-Mediated Pharmacokinetic Interactions With Midazolam, Cyclosporine, and Ritonavir in Healthy Volunteers

Amenamevir (formerly ASP2151) is a helicase‐primase inhibitor being developed for the treatment of herpesvirus infection. Amenamevir is both a substrate and inducer of cytochrome P450 (CYP) 3A4. Three studies were done in healthy volunteers to investigate potential CYP3A pharmacokinetic interactions with the following drugs: (1) Midazolam (probe substrate for CYP3A): After 10 days’ pretreatment with amenamevir 400 mg daily, geometric mean maximum concentration of drug in blood plasma (C_max) and area under the plasma drug concentration‐time curve from time zero to infinity (AUC_0‐∞) of midazolam 7.5 mg were about 68% and 51%, respectively, of those after midazolam alone. (2) Cyclosporine (substrate and inhibitor of CYP3A): After 5 days’ pretreatment with cyclosporine 100 mg twice daily, geometric mean C_max of amenamevir after 400‐mg and 1200‐mg single doses was, respectively, about 66% and 69%, and AUC_0‐∞ about 82% and 79%, of those after amenamevir alone. (3) Ritonavir (inhibitor of CYP3A): When given with single doses of ritonavir 600 mg, geometric mean C_max of amenamevir after 400‐mg and 1200‐mg single doses was, respectively, about 1.4 and 1.6 times higher, and geometric mean AUC_0‐∞ about 2.6 and 3.3 times higher, than after amenamevir alone. Amenamevir has the potential to be involved in CYP3A‐mediated pharmacokinetic interactions in clinical practice.

Midazolam plasma concentration after anesthesia premedication in clinical routine - an observational study : Midazolam plasma concentration after anesthesia premedication

BACKGROUND

Midazolam is commonly used as a pre-anesthesia anxiolytic. It`s elimination may not be fast enough for short procedures. In orally premedicated patients we obtained midazolam plasma concentrations at the end of surgical procedures and compared those to concentrations at anesthesia induction.

METHODS

The study was conducted prospectively with consent of the local ethics committee (Ethikkomission Kanton Thurgau, Switzerland) and carried out with written informed consent of each patient. Female patients aged 20 to 60 years undergoing elective procedures with general anesthesia were included, and were divided in two groups according to the planned surgical time: group S (<30 min) and group L (90-120 min), respectively. All patients received 7.5 mg Midazolam po as premedication. Blood samples were drawn at anesthesia induction, and at the end of surgery. Data were compared with t-test (independent samples; significance level p <0.05).

RESULTS

Twenty-five patients per group were included. Four patients were excluded from analysis, since midazolam was not detectable in any samples. Time of premedication to the 1st blood sample was not statistically different between groups, neither were Midazolam plasma levels at this time point (p = 0.94). None of the patients from group L (n = 24), but five patients in group S (n = 22) did have a higher plasma level of Midazolam at the end of the case compared to the beginning.

CONCLUSIONS

The elimination half-life of oral Midazolam can lead to higher plasma levels at the end of a short procedure compared to those at induction of anesthesia.

TRIAL REGISTRATION

German Clinical Trials Register (Deutsches Register Klinischer Studien), DRKS00005429 ; date of registration 3^rd January 2014.

Oral versus intranasal midazolam premedication for infants during echocardiographic study

Movement and anxiety during echocardiographic study may reduce the reliability and affect the quality of echocardiographic images. Thus, sedation is an essential component when it is performed in infants. This randomized, single-blinded, placebo-controlled study was undertaken to evaluate the acceptability and effectiveness of intranasal midazolam (INM) versus oral midazolam (OM) in infants during transthoracic echocardiography. Eighty patients between the ages of 6 mo and 3 y who presented for elective echocardiographic study were divided into 3 groups: the OM group received 0.4 mg/kg of injectable midazolam mixed with an equal volume of cherry juice, the INM group received 0.2 mg/kg as drops,and the control group was given oral cherry juice or intranasal serum physiologic. A blinded clinician assessed and scored the level of sedation and comfort during the procedure for each child, and a score for ease of administration was recorded by the nurse. The intranasal route was more acceptable to infants than the oral route (P<.001). No significant difference in the effects of sedation was observed between the OM group and the INM group (P=.583), but significant differences were observed between the sedated groups and the control group (P<.001). The procedure was significantly more comfortable in groups given OM and INM than in the control group (P<.001). Although no difference in sedation score was seen between the oral and nasal routes, INM was better accepted by infants than OM. Echocardiography was performed more reliably and comfortably in those given midazolam than in those in the control group.

Sublingual morphine may be a suitable alternative for pain control in children in the postoperative period

The purpose of this pilot study was to compare the effects of sublingual morphine with intravenous morphine in the treatment of postoperative pain following adenotonsillectomy in children. Twenty-nine children scheduled for adenotonsillectomy were randomly assigned to group 1 (n=14) receiving 0.1 mg x kg(-1) sublingual morphine and group 2 (n=15) 0.1 mg x kg(-1) intravenous morphine followed by 1 mg x kg(-1) diclofenac rectally in both groups after induction of anaesthesia. Postoperatively, time to first eye opening, sedation score, pain score, time for further analgesia requests and incidence of nausea and vomiting were recorded. There was no statistical significant difference in any of these parameters between the two groups. The results suggest that sublingual morphine may be a suitable alternative to various other routes of opioid administration in children, but further investigations of the sublingual route of administration of opioids in children are required.

The comparative dose-response effects of melatonin and midazolam for premedication of adult patients: a double-blinded, placebo-controlled study

We designed this prospective, randomized, double-blinded, placebo-controlled study to compare the perioperative effects of different doses of melatonin and midazolam. Doses of 0.05, 0.1, or 0. 2 mg/kg sublingual midazolam or melatonin or placebo were given to 84 women, approximately 100 min before a standard anesthetic. Sedation, anxiety, and orientation were quantified before, 10, 30, 60, and 90 min after premedication, and 15, 30, 60, and 90 min after admission to the recovery room. Psychomotor performance of the patient was evaluated at these times also, by using the digit-symbol substitution test and Trieger dot test. Patients who received premedication with either midazolam or melatonin had a significant decrease in anxiety levels and increase in levels of sedation preoperatively compared with control subjects. Patients in the three midazolam groups experienced significant psychomotor impairment in the preoperative period compared with melatonin or placebo. After operation, patients who received 0.2 mg/kg midazolam premedication had increased levels of sedation at 90 min compared with 0.05 and 0. 1 mg/kg melatonin groups. In addition, patients in the three midazolam groups had impairment of performance on the digit-symbol substitution test at all times compared with the 0.05 mg/kg melatonin group. Premedication with 0.05 mg/kg melatonin was associated with preoperative anxiolysis and sedation without impairment of cognitive and psychomotor skills or affecting the quality of recovery.

IMPLICATIONS

Premedication with 0.05 mg/kg melatonin was associated with preoperative anxiolysis and sedation without impairment of cognitive and psychomotor skills or affecting the quality of recovery.

The effects of age and gender on the optimal premedication dose of intramuscular midazolam

We conducted a double-blind study on the effects of age and gender on the optimal premedication dose of i.m. midazolam. We randomly divided 100 male and 100 female patients in each of three age groups: A = 20-39 yr, B = 40-59 yr, and C = 60-79 yr (total 600 patients) into five groups according to midazolam dosage: 0.04, 0.06, 0.08, 0.10, and 0.12 mg/kg. Midazolam was injected i.m. with atropine 0.01 mg/kg 15 min before the induction of anesthesia. Blood pressure (BP), heart rate, respiratory rate, oxygen saturation (SpO2), sedation level, tongue root depression, eyelash reflex, and anterograde amnesia were monitored. There were no significant differences between male and female patients in any variables in any age. Decrease of SpO2 and loss of eyelash reflex were seen with midazolam 0.10 mg/kg in Group A, and with 0.08 mg/kg in Group B. In Group C, decreases in BP and SpO2, loss of eyelash reflex, and depression of the tongue root were observed with midazolam 0.06 mg/kg. In conclusion, the optimal doses of i.m. midazolam administered 15 min before the induction of anesthesia in male or female patients were 0.08, 0.06, and 0.04 mg/kg for Groups A, B, and C, respectively.

IMPLICATIONS

Midazolam is the most widely used preoperative anxiolytic drug. Our purpose was to evaluate the optimal dose of i.m. midazolam that would maximize the desired effects and minimize the side effects in a common clinical setting. Results indicate that age, but not gender, should affect the i.m. midazolam dose selected for premedication.