PubMed Health⌕ Search

Biomedical subjects

U Bang

Publications and source records attributed to U Bang.

16 recordsLinked to original sources
PubMed1998

Pharmacokinetics of bambuterol in subjects homozygous for the atypical gene for plasma cholinesterase.

AIMS: It has been assumed that both plasma cholinesterase (EC 3.1.1.8) and oxidative enzymes are needed for optimum formation of the bronchodilator terbutaline from its biscarbamate prodrug bambuterol. The present study aimed at investigating the fate of bambuterol in subjects with deficient plasma cholinesterase but with normal oxidative (CYP2D6) capability. METHODS: The pharmacokinetics of bambuterol and terbutaline were studied in four healthy subjects (two men and two women) being homozygous for the atypical gene for plasma cholinesterase. Their oxidative metabolism was apparently good as they were all rapid metabolizers of debrisoquine. Bambuterol hydrochloride 20 mg was given orally once daily for 10 days, and plasma and urine samples were taken for 1.5 days (plasma) and 4.5 days (urine) after administration of the last dose. RESULTS: The pharmacokinetic parameters in the present study were grossly similar to those found in a study of bambuterol in subjects with normal plasma cholinesterase activity (N). However, subjects with atypical cholinesterase had a shorter terminal half-life of bambuterol (a measure of uptake rate), 4.8-12.6 h vs 8.3-22.3 h in N, and slightly higher plasma concentrations of bambuterol (average concentrations 1.9-3.7 nmol l(-1) vs 1.5-3.1 nmol l(-1) in N). Peak/trough terbutaline plasma concentrations ratios (2.1-3.2) were somewhat increased, but average plasma concentrations (8.3-14.5 nmol l(-1)) and terminal half-life (16.5-21.8 h) of terbutaline did not differ. CONCLUSIONS: In Caucasian populations, one subject out of 2500 is homozygous for the atypical gene for plasma cholinesterase. The atypical enzyme has a much lower affinity for bambuterol than the normal enzyme. Nevertheless, the subjects with atypical cholinesterase were able to produce terbutaline as efficiently as normal subjects. This might be explained by an altered uptake and metabolism in the absence of plasma cholinesterase, or the importance of this enzyme for the formation of terbutaline from bambuterol in vivo may have been overestimated.

Adult↗
PubMed1996

Pain control after dental surgery: a double-blind, randomised trial of lornoxicam versus morphine.

Lornoxicam is a new non-steroidal anti-inflammatory drug of the oxicam class. This randomised, double-blind, placebo controlled trial compared the analgesic efficacy and tolerability of intramuscular (IM) injections of lornoxicam (4, 8, 16 and 20 mg) with morphine (10 and 20 mg) and placebo in 252 patients with mainly moderate to severe pain following surgical removal of an impacted mandibular third molar. Patients treated with lornoxicam or morphine experienced a significantly greater cumulative pain relief over the 4-h post-injection period (TOTPAR0-4) than placebo recipients. This effect appeared to be dose-dependent, with patients in the lornoxicam 4 mg or morphine 10 mg groups recording significantly lower TOTPAR0-4 scores than patients in the higher dosage groups of these drugs. No significant difference was detected between the morphine 20 mg group and the lornoxicam 8, 16 and 20 mg groups. Lornoxicam was well tolerated at all doses and was associated with a significantly lower incidence of adverse events than morphine 10 or 20 mg. Thus, the analgesic efficacy of IM lornoxicam at doses > or = 4 mg is superior to placebo, and doses > or = 8 mg are at least as effective as IM morphine 20 mg. Furthermore, lornoxicam possesses a more favourable tolerability profile than morphine and thus represents an attractive alternative for the treatment of moderate to severe acute pain.

Adolescent↗
PubMed1992

The accuracy of train-of-four monitoring at varying stimulating currents.

Train-of-four (TOF) monitoring of neuromuscular block at submaximal current stimulation has been recommended because it is less painful than monitoring at supramaximal stimulation. The measurement error, however, when using submaximal stimulation has not as yet been fully elucidated. The authors therefore quantified the measurement error of TOF monitoring at low currents near the initial threshold for stimulation (ITS) by assessing precision (the difference between duplicated TOF ratios measured at the same current) and accuracy (the difference between TOF ratios at lesser currents and the TOF ratio at 58 mA, which served as the reference standard method). A stable neuromuscular block at a TOF ratio of 0.40 and subsequently 0.70 was established in 20 patients using a continuous infusion of atracurium. The ulnar nerve was stimulated at the wrist using TOF stimulation, and the evoked twitch response of the adductor pollicis muscle was measured with a force-displacement transducer. The stimulating current was varied in 5-mA steps between ITS and 55 mA. Whereas there were no statistical significant differences between the mean TOF ratios at the different currents, the standard deviation increased with decreasing currents (P less than 0.01 at currents less than 40 mA). The precision was acceptable except at ITS, where the limits of precision (mean intracurrent difference in TOF ratio +/- two standard deviations) exceeded 0.05, which was the chosen acceptable difference. The standard deviation of the accuracy was significantly increased at currents less than or equal to ITS + 25 mA (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Electric Stimulation↗
PubMed1990

Does perioperative tactile evaluation of the train-of-four response influence the frequency of postoperative residual neuromuscular blockade?

The authors conducted a randomized controlled clinical trial to evaluate the usefulness of perioperative manual evaluation of the response to train-of-four (TOF) nerve stimulation. A total of 80 patients were divided into four groups of 20 each. For two groups (one given vecuronium and one pancuronium), the anesthetists assessed the degree of neuromuscular blockade during operation and during recovery from neuromuscular blockade by manual evaluation of the response to TOF nerve stimulation. In the other two groups, one of which received vecuronium and the other pancuronium, the anesthetists evaluated the degree of neuromuscular blockade solely by clinical criteria. The use of a nerve stimulator was found to have no effect on the dose of relaxant given during anesthesia, on the need for supplementary doses of anticholinesterase in the recovery room, on the time from end of surgery to end of anesthesia, or on the incidence of postoperative residual neuromuscular blockade evaluated clinically. The median (and range of) TOF ratios recorded in the recovery room were 0.75 (0.33-0.96) and 0.79 (0.10-0.97) in the vecuronium groups monitored with and without a nerve stimulator, respectively. These ratios were significantly higher than those found in the pancuronium groups, which wre 0.66 (0.06-0.90) and 0.63 (0.29-0.95), respectively. However, no difference was found between the vecuronium and pancuronium groups in the number of patients showing clinical signs of residual neuromuscular blockade, as evaluated by the 5-s head-lift test.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

The effect of bambuterol (carbamylated terbutaline) on plasma cholinesterase activity and suxamethonium-induced neuromuscular blockade in genotypically normal patients.

Bambuterol (the bisdimethylcarbamate prodrug of terbutaline) is a new bronchodilator with a prolonged duration of action due to its inhibition of plasma cholinesterase during metabolism. The effect of bambuterol on suxamethonium-induced neuromuscular blockade was studied in 10 patients undergoing elective laparotomy. Thirty mg of bambuterol was given 2 h before anaesthesia, which was performed with thiopentone, fentanyl, halothane and nitrous oxide in oxygen. Neuromuscular function was monitored using supramaximal train-of-four stimulation of the ulnar nerve and a force displacement transducer. Suxamethonium 1 mg.kg-1 was given i.v. for endotracheal intubation. Plasma cholinesterase activity was measured before and after intake of bambuterol and during anaesthesia. The results from the 10 patients were compared with those of 41 patients not given bambuterol but otherwise studied during the same conditions. Following bambuterol, all patients had a significant decrease of plasma cholinesterase activity (P less than 0.001) and the suxamethonium-induced blockade was 3-4 times prolonged compared to patients not given bambuterol (P less than 0.001). Five patients with very low plasma cholinesterase activity developed a long-lasting phase II block.

Adult↗
PubMed1990

The effect of bambuterol on plasma cholinesterase activity and suxamethonium-induced neuromuscular blockade in subjects heterozygous for abnormal plasma cholinesterase.

Bambuterol is a new bronchodilator which is also a reversible inhibitor of plasma cholinesterase. In patients with normal plasma cholinesterase genotype, bambuterol prolongs suxamethonium-induced neuromuscular blockade. In the present study, we investigated the interaction of bambuterol and suxamethonium in nine patients heterozygous for abnormal plasma cholinesterase during anaesthesia with fentanyl, thiopentone, halothane and nitrous oxide in oxygen. The patients (seven E1uE1a and two E1uE1s) were given 20 mg of bambuterol orally 2 h before anaesthesia. Suxamethonium 1 mg.kg-1 was given for tracheal intubation. The neuromuscular function was monitored using train-of-four (TOF) stimulation of the ulnar nerve and a force displacement transducer. Plasma cholinesterase activity decreased in all patients following bambuterol (P less than 0.001). In patients with genotype E1uE1a, median time to 90% recovery of twitch height and TOF ratio greater than or equal to 0.7 (37.5 min) was prolonged compared to 28 E1uE1a patients not treated with bambuterol (14.0 min) (P less than 0.001). Four of these patients developed a phase II block apparently not correlated to plasma cholinesterase activity. In the E1uE1s; patients, full recovery was seen after 22.0 and 31.4 min, respectively. It is concluded that in patients heterozygous for abnormal plasma cholinesterase, bambuterol 20 mg taken 2 h before anaesthesia causes a 2-3 times prolongation of the neuromuscular blockade following suxamethonium 1 mg.kg-1 and in some patients a phase II block.

Adult↗
PubMed1990

Effect of combined prednisolone, epidural analgesia and indomethacin on pain, systemic response and convalescence after cholecystectomy.

Twelve patients undergoing elective cholecystectomy received as analgesic medication a single dose of methylprednisolone (30 mg/kg) preoperatively and thoracic epidural analgesia with plain bupivacaine for 48 hours + epidural morphine 4 mg and systemic indomethacin 100 mg, both every 8 hours for 96 hours. Assessments of pain, various parameters of response to injury, peak flow and subjective fatigue were made preoperatively, before and 3 and 6 hours after skin incision and 1, 2, 4 and 8 days postoperatively. These patients were matched with 24 from a previous study who were treated with either intermittent nicomorphine and acetaminophen or with epidural analgesia + systemic indomethacin as analgesic medication. Preoperative methylprednisolone resulted in improved pain relief, with concomitantly reduced need for epidural bupivacaine, prevention of hyperthermic response, improved postoperative pulmonary function and lessened fatigue, while the leucocytic and acute phase responses were unmodified. There were no side effects. These results may be explained by inhibition of various trauma-induced inflammatory mediators.

Adult↗
PubMed1988

The Accelograph: a new neuromuscular transmission monitor.

A new neuromuscular transmission monitor based on measurement of acceleration is presented. The monitor consists of an acceleration transducer, i.e. a piezo-electric ceramic wafer with an electrode on each side, and a stimulation and computing unit. The transducer can be fastened to the thumb, and when the finger is moved in response to nerve stimulation a voltage difference develops between the two electrodes. The voltage is then measured and registered in the computing unit. The acceleration transducer does not require preload, but merely that the muscle on which the measurement is being made can move freely. The accelograph is therefore easy to set up and operate. In daily clinical practice it has proved possible, using this new apparatus, to achieve reliable evaluation of the degree of non-depolarizing neuromuscular blockade in less than 2 min.

Acceleration↗
PubMed1988

Subarachnoid versus epidural bupivacaine 0.5% for caesarean section.

In order to compare subarachnoid (spinal) and epidural block for caesarean section, 40 women were randomly allocated to spinal or epidural analgesia with bupivacaine. The median dose of bupivacaine was 13 mg in the spinal group versus 155 mg in the epidural group. The mean time from induction to delivery was 32 min shorter in the spinal group (P less than 0.001). In the spinal group one woman was excluded because of spontaneous labour. Three patients in the spinal and one in the epidural group failed to develop adequate analgesia to initiate surgery. For the remaining patients both techniques provided good analgesia during operation. Postoperatively, epidural block provided better pain relief. The patients in the epidural group had a lower pain score during the first 4 h after the operation (P less than 0.01). In spite of similar haemodynamic changes in the two groups, the mean base deficit in umbilical cord blood at delivery was higher in the spinal group (P less than 0.05).

Acid-Base Equilibrium↗
PubMed1986

Plasma concentrations of flunitrazepam (Rohypnol) following oral and sublingual administration.

Flunitrazepam (Rohypnol) 2.0 mg was given as a single dose by the oral or sublingual route to ten volunteers using a cross-over design. Plasma concentrations of the drug were measured by gas-liquid chromatography for up to 6 hours after administration. The highest mean concentration occurred 45 min after administration irrespective of route. No significant differences were found between the two treatments at any time. Since the sublingual route compares favorably with other routes of administration, these findings suggest that sublingual flunitrazepam is valuable for premedication.

Administration, Oral↗
PubMed1985

Investigation of TSH dependency, circulating thyroid autoantibody, and morphological features of recurrent nontoxic goitre.

Pathogenetical factors possibly responsible for recurrence of nontoxic goitre in a nonendemic area are evaluated. A group of 22 female patients admitted for surgical treatment of recurrent nontoxic goitre was compared with a control group of 86 female nontoxic goitrous patients not operated upon before. Preoperative serum baseline thyrotrophin levels in the recurrent goitre group were low normal and did not differ significantly from those in the control group. Circulating thyroid microsomal autoantibodies, thyroglobulin antibody titers, and the densities of lymphocytic aggregation in goitrous tissue did not differ significantly in the two groups. Thus, none of the parameters studied were likely explanations of regrowth of goitre.

Autoantibodies↗
PubMed1985

Sublingual flunitrazepam for premedication.

The clinical effects of a standard 2 mg flunitrazepam tablet given sublingually for premedication were evaluated in a group of 50 patients undergoing otorhinolaryngologic surgery. A comparable group of 49 patients received 10 mg of diazepam orally. The degree of sedation and anxiety was assessed objectively and subjectively before induction of anaesthesia. Flunitrazepam produced better sedation judged by the observer as well as by the patients. There was less anxiety in the flunitrazepam group but this was not statistically significant. Side effects were few and patient acceptability high. Sublingual premedication using flunitrazepam could be a useful alternative to other forms of premedication.

Administration, Oral↗
PubMed1985

Thyroid function after resection for non-toxic goitre with special reference to thyroid lymphocytic aggregation and circulating thyroid autoantibodies.

A series of 91 patients operated on for non-toxic goitre was followed systematically during 24 months post-operatively with regard to thyroid function. A thyroid remnant of at least 5 to 8 g was left in the majority of cases, and thyroid replacement was not given. Histopathological grading was performed on goitrous specimens with reference to lymphocytic infiltration. Thyroglobulin antibodies and thyroid microsomal antibodies were determined pre-operatively. Goitre resection provoked a high, but transient increase in serum thyroid stimulating hormone (TSH) levels with peak values 3 to 6 months after operation. Twenty-four months after surgery serum TSH values had normalized, but were still slightly elevated in patients with bilateral surgery and high lymphocytic infiltration, 9% of the patients. The concentration of serum free thyroxine index (FT4I) and serum total triiodothyronine (TT3) decreased after operation, but within reference range. Twenty-four months after surgery, serum FT4I was back to baseline values, while serum TT3 was still lowered compared to the pre-operative level. None of the patients developed overt hypothyroidism. Occurrence of circulating thyroid autoantibodies was not related to post-operative changes in thyroid parameters. We conclude that thyroid replacement therapy seems not to be indicated routinely following resection for non-toxic goitre, but precaution should be taken in case of bilateral resection and high lymphocytic infiltration of goitrous specimens.

Adolescent↗