Midazolam for the treatment of phantom limb pain exacerbation: preliminary reports.

Phantom pain is one of the most difficult intractable pains to manage. The pain may result from the imbalance of self-sustaining neural activity that exceeds the inhibitory control. The management of acute severe exacerbation of phantom pain is extremely difficult. Midazolam acts by potentiation of gamma aminobutyric acid (GABA) and enhance the inhibitory action of glycine receptor at spinal neurons. We describe two preliminary reports of complete pain relief of severe phantom pain exacerbation by intravenous midazolam 3-5 mg.

Brachial plexus injury and pain: incidence and the effects of surgical reconstruction.

A prospective study of pain after brachial plexus injury was carried out on 246 patients with at least 2 years follow-up. All of them had closed traction injury from motorcycle accidents. There were 16 females and 230 males aged from 16 to 44 years old. The patients' biodata, onset of pain, characteristics of pain and treatment were recorded. Changes in pain after conservative and operative treatment and the outcome of treatment were analysed. Two hundred and nineteen patients (89%) had significant pain and 182 patients (74%) had severe pain. Most of them had continuous pain with 2 to 20 peaks of severe pain per day. Crushing type of pain was the most common but mixed type of pain caused the most distress. Conservative treatment before surgery could relieve the pain in 39 patients (15.8%). Surgical reconstruction could further relieve the pain in 176 patients (80.36%). However, 21 patients (8.5%) still had severe pain. Improvement in sensory function had more effect on pain reduction than motor function.

Propofol vs isoflurane for neurosurgical anesthesia in Thai patients.

Sixty Thai patients, ASA class I-II, Glasgow coma score of 15 undergoing elective intracranial surgery were randomly assigned to 2 groups. In group I, 30 patients were induced with thiopental 3-5 mg/kg, intubation with succinylcholine 1-2 mg/kg and then maintained with 60 per cent N2O in O2, isoflurane and vecuronium as a muscle relaxant. In group II, 30 patients received fentanyl 50 micrograms, propofol 1.0-2.5 mg/kg for induction and vecuronium 0.08 mg/kg for intubation then maintained with 60 per cent N2O in O2, continuous infusion of propofol 2-12 mg/kg/h and vecuronium as a muscle relaxant. Controlled ventilation in both groups was set to maintain PET CO2 in the range of 28-35 mmHg. 3 patients (1 in group I and 2 in group II) were excluded from the study due to surgical problems. There was no statistical difference in age, sex, ASA status, weight, duration of anesthesia. Group II had a more stable systolic BP, Diastolic BP and Pulse rate than Group I during induction and emergence from anesthesia. Glasgow coma scores in the recovery period, Group II had higher scores than Group I at 5 and 15 minutes but not at 30 minutes. Mean recovery times (eye opening) was 14.03 +/- 4.85 minutes in group I which is significantly different from 10 +/- 5.17 minutes in group II. The cost of anesthesia in group II was 1.3 times that of group I. In conclusion, although neurosurgical anesthesia for Thai patients with fentanyl-propofol technique produces more stable blood pressure during intubation and emergence, rapid recovery from anesthesia and a higher Glasgow coma score, the cost of anesthesia is more expensive. Furthermore, this technique is more difficult and needs more experience.

Effect of intraoperative fluid on blood glucose level in neurosurgery.

There is a considerable controversy regarding glucose administration during intracranial surgery. However, recent animal and human studies suggest that hyperglycemia exacerbates ischemic brain damage and intraoperative hypoglycemia may not be a concern if the surgical procedure is less than 4 hours. We, therefore, studied the blood glucose in neurosurgery with craniotomy in 90 Thai patients, divided into 3 groups. 30 patients in each group received balanced salt solution (0.9% NSS), 5 per cent glucose rate 60-80 ml/h and 5 per cent glucose rate more than 120 ml/h. Blood for the determination of glucose concentration was obtained after induction and every 2 hours later until the end of the surgery. There was one male patient in group I who received balanced salt solution (0.9% NSS) had blood glucose concentration lowered to 57 mg% at 4 hours after induction. The patients in group II who received 5 per cent glucose solution at maintenance rate did not have hyperglycemia (161.20 +/- 38.30 mg%). In group III; patients given 5 per cent glucose infusion at the rate of more than 120 ml/h had hyperglycemia (236.75 +/- 63.57 mg%) at 6 hours. In conclusion, we suggest that in Thai patients undergoing neurosurgical procedures; blood glucose levels should be checked intraoperatively if glucose is withheld from the intraoperative fluid regimen. Otherwise 80 ml/h of 5 per cent dextrose intravenous infusion should be given to the patients to prevent hypoglycemia.

Efficacy of prophylactic ondansetron in Thai patients undergoing gastrointestinal tract surgery.

Postoperative nausea and vomiting (PONV) although frequently is considered a minor postoperative complication, it may be greatly trouble some especially in ambulatory surgical patients. This study was performed to compare the efficacy and safety of a single intravenous bolus dose of ondansetron 4 mg with the placebo in the prevention of PONV and to assess the safety and tolerability in Thai patients. By using the randomized, double-blind, placebo controlled study design, we enrolled 82 Thai male and female patients, ASA physical status I or II, between the ages of 12 and 75 year undergoing gastrointestinal tract surgery with general anesthesia in the study. A single intravenous bolus dose of ondansetron 4 mg or a single dose of placebo was administered immediately prior to the induction of the anesthesia. The patients were followed for 24 hours to assess PONV and adverse events. We found that intravenous ondansetron 4 mg seemed to be effective and safe in the prevention of PONV especially in female patients (P = 0.037) based on clinical observation. However there was no statistical significance between groups. None of the patients in both groups had any adverse events. In addition, there was no significant difference between preoperative and postoperative abnormalities of liver enzymes. Also we had found no difference in patient satisfaction between two groups.

The use of tramadol hydrochloride in the treatment of post-anesthetic shivering.

Tramadol at the dosage of 1 mg per kg body weight was given intravenously to 110 adult patients who developed postoperative shivering. All patients were cured of the shivering after 45 seconds to 6 minutes. Seventy-four per cent stopped within 2 minutes after the injection. There were five patients who had recurrence of shivering after 10 to 30 minutes and this was easily stopped by another dosage of the drug. There were very few minor side effects and they required no medical treatment.