Mixture Of Midazolam Research Articles

ISOFLURANE AND OTHER COMMONLY USED ANAESTHETICS DO NOT PROTECT THE ISOLATED BUFFER PERFUSED MOUSE HEART FROM ISCHEMIA‐REPERFUSION INJURY

1. Some anaesthetic agents such as barbiturates and opioids possess cardioprotective properties in rats, rabbits, dogs and pigs. The purpose of this study was to evaluate the effects of some commonly used anaesthetic agents (pentobarbital, isoflurane and a mixture of midazolam, fentanyl and fluanisone) on the tolerance of the isolated mouse heart to ischaemia-reperfusion injury. 2. The isolated, Langendorff-perfused hearts were subjected to 45 min of global ischaemia followed by 60 min of reperfusion. Left ventricular pressures, heart rate and coronary flow were measured and infarct size was determined using triphenyltetrazolium staining. 3. There were no differences in haemodynamic variables during reperfusion between groups. Infarct size was not influenced by the choice of anaesthesia. 4. None of the anaesthesia protocols exerted significant protective effects on the ischaemic-reperfused isolated mouse heart performance. In mice, isoflurane as well as pentobarbital, opioids and benzodiazepines may be safely used for anaesthesia without a risk of protective side-effects in isolated mouse heart studies.

Comparison of Sedation Requirements for Cataract Surgery under Topical Anesthesia or Retrobulbar Block

Topical anesthesia is increasingly being used for cataract surgery. However, it is believed that topical anesthesia causes an increased risk of intraoperative complications from unrestricted eye movement and insufficient pain control and more need for sedation. It is difficult to compare pain and anxiety experienced by individual patients; therefore, the authors used the method of patient-controlled sedation to determine whether there is a difference in sedation requirements under topical or retrobulbar anesthesia. In this prospective study, patients received either topical anesthesia (n=87) or retrobulbar block (n=104) and self-administered a mixture of midazolam (0.5 mg) and fentanyl (25 microg) in increments using a patient controlled analgesia infuser to achieve sedation. At the end of surgery, patients rated their pain on a 10-point numerical rating scale and their comfort on a 5-point scale. The number of demands and deliveries were noted from the patient controlled analgesia infuser display. Pain scores were between 0 and 2 in 95.4% in the topical and in 94.2% in the retrobulbar group (p>0.05). Patient comfort was equal in both groups with 2.94+/-0.92 in the topical group and 2.92+/-0.99 in the retrobulbar group (p>0.05). Mean sedation requirements were similar in both groups: 26.4% of patients in the topical group and 19.2% in the retrobulbar group did not request any sedation (not significant, p>0.05). Sedation requirements were similar for cataract surgery under topical and retrobulbar anesthesia.

Oral Midazolam Syrup Provides Consistent Sedation in Children

Midazolam sedation for children has generally been provided by ad hoc mixture of midazolam with another substance to hide the bitter taste. In a

Fentanyl and midazolam anaesthesia for coronary bypass surgery: a clinical study of bispectral electroencephalogram analysis, drug concentrations and recall

Bispectral index (BIS) was assessed as a monitor of depth of anaesthesia during fentanyl and midazolam anaesthesia for coronary bypass surgery. In 10 patients given morphine premedication, anaesthesia was induced with a combination of midazolam and fentanyl and thereafter maintained with a continuous infusion of a mixture of midazolam and fentanyl 5 and 50 micrograms kg-1 h-1, respectively. BIS was recorded continuously but not shown to the attending anaesthetist. Plasma concentrations of midazolam and fentanyl were measured five times during the procedure. An auditory stimulus was given during bypass. All patients were interviewed twice after operation for explicit and implicit recall. No patient had any anaesthetic complications. BIS decreased during anaesthesia, but varied considerably during surgery (range 36-91) with eight patients having values > 60. Midazolam and fentanyl drug concentrations did not correlate with BIS. No patient reported explicit or implicit recall. During clinically adequate anaesthesia with midazolam and fentanyl BIS varies considerably. The most likely reason is that BIS is not an accurate measure of the depth of anaesthesia when using this combination of agents.

ミダゾラム（ドルミカム）・ブトルファノール（スタドール）持続注入回路内に析出した結晶成分の分析とその成因

Resolution of the problems appearing in the clinical departments with relation to drug utility is a very important task for hospital pharmacists. The chief nurse of the surgery section recently asked us to examine the crystal material often appearing in the continuous infusion line of Dormicum®-Stadol® (2: 1) several hours after infusion of other medicines. The crystals were examined by high performance liquid chromatography. The retention time of the crystals was the same as that of midazolam, and the crystals were identified to be midazolam. The main cause of the formation of crystals was found to be the rise in the pH of midazolam injection due to the mixing with butorphanol injection. Moreover, the changes in ion strength and ion components in the solution affected the appearance of the crystals. Thus, midazolam should not be infused with butorphanol. If a mixture of midazolam and other medicines must be infused continuously, medical workers should check for the appearance of the crystals.

Nasal midazolam and ketamine for paediatric sedation during computerised tomography.

We have studied the sedation achieved with a mixture of midazolam (0.56 mg/kg-1) and ketamine (5 mg/kg-1) administered nasally in 30 children weighing less than 16 kg undergoing computerised tomography. Assessment was two fold using a visual analogue scale; the radiologist/radiographer rated the exam from "failed examination" to "perfect working conditions" while the anesthetist's assessment ranged from "poor sedation" to "perfect sedation with clinical well being". This new method proved to be effective alone in 83% of the cases and there were no complications. The rapid onset obtained after intranasal midazolam and ketamine offers advantages over orally or rectally administered drugs. The absence of respiratory depression and oxygen desaturation suggests that this technique is safe and efficient in the CT room with its particular working conditions.

Recovery after total intravenous anaesthesia using combined midazolam/alfentanil infusion and reversal with flumazenil

One of the major problems with total intravenous anaesthesia (TIVA) is postoperative sedation, possibly with respiratory depression. The aim of the present study was to evaluate the recovery characteristics after TIVA using a continuous infusion of a mixture of midazolam and alfentanil with flumazenil reversal before extubation. This method was compared to balanced anaesthesia using midazolam, alfentanil and nitrous oxide without flumazenil reversal. The degree of sedation was measured by reaction time test, Glasgow Coma Scale, cipher copying test and subtraction test. We found significantly faster reaction times postoperatively in the TIVA group (n = 15) compared to the balanced group (n = 13), despite larger doses of both midazolam (median 21 mg versus 9 mg) and alfentanil (median 5.9 mg versus 4.5 mg). The other tests revealed no difference between the groups. One patient became resedated after flumazenil. We conclude that the TIVA technique described here resulted in slightly better recovery characteristics, offering a usable alternative to balanced anaesthesia.

Patient-Controlled Sedation During Epidural Anesthesia

The purpose of this study was to evaluate the feasibility and advantages or disadvantages, if any, of patient-controlled sedation compared with sedation administered by the anesthesiologist during surgical epidural anesthesia. Forty patients were divided at random into two groups with 20 patients in each group. Patients in group 1 received 0.5-1.0 mg intravenous midazolam and 25-50 micrograms intravenous fentanyl in increments administered by the anesthesiologist to achieve intraoperative sedation; patients in group 2 self-administered a mixture of midazolam (0.5 mg) and fentanyl (25 micrograms) in increments using an Abbott Lifecare PCA infuser to achieve sedation. Demographics of the patients, the types of surgery performed, doses of midazolam and fentanyl administered in a given period of time, and the level of sedation maintained during epidural anesthesia and surgery were similar in both groups. Patients in the self-administered group, however, rated their level of comfort during anesthesia and surgery higher than did those in the anesthesiologist-controlled sedation group. This could have been due to a positive psychological effect produced by allowing patient to feel that they have some control over their situation. The findings of this study indicate that patient-controlled sedation using a combination of midazolam and fentanyl is a safe and effective technique that provides intraoperative sedation ranked better by patients than that provided by anesthesiologists using the same drugs. More studies are, however, needed to determine the best choice of drug(s), the doses, the lock-out intervals, and the possible use of continuous infusion with patient-controlled sedation.

Hemodynamic Effects of Intravenous Midazolam‐Xylazine‐Butorphanol in Dogs

The hemodynamic effects of a mixture of midazolam (1.0 mg/kg), xylazine (0.44 mg/kg), and butorphanol (0.1 mg/kg) were evaluated in six adult dogs. The dogs were anesthetized with isoflurane for instrumentation. As the dogs returned to consciousness, baseline values were recorded and the midazolam-xylazine-butorphanol mixture and glycopyrrolate (0.01 mg/kg) were administered intravenously (IV). Hemodynamic data were recorded 3, 10, 20, 30, 40, 50, and 60 minutes after injection. Mean arterial pressure (AP), mean pulmonary arterial pressure (PAP), heart rate (HR), rate-pressure product (RPP), mean pulmonary capillary wedge pressure (PCWP), systemic vascular resistance (SVR), and right ventricular stroke work index (RVSWI) were increased significantly above baseline values. Cardiac output (CO), stroke volume (SV), cardiac index (CI), stroke index (SI), mean central venous pressure (CVP), and left ventricular stroke work index (LVSWI) were decreased significantly below baseline values. When administered IV at the dosages used in this study, midazolam-xylazine-butorphanol-glycopyrrolate induced profound acute alterations in several critical hemodynamic variables.