Search PubMed⌕ Search

Biomedical subjects

C Verghese

Publications and source records attributed to C Verghese.

69 records · Page 4Linked to original sources
PubMed1992

Metabolic acidosis and fatal myocardial failure after propofol infusion in children: five case reports.

OBJECTIVE: To examine the possible contribution of sedation with propofol in the deaths of children who were intubated and required intensive care. DESIGN: Case note review. SETTING: Three intensive care units. SUBJECTS: Five children with upper respiratory tract infections aged between 4 weeks and 6 years. RESULTS: Four patients had laryngotracheo-bronchitis and one had bronchiolitis. All were sedated with propofol. The clinical course in all five cases was remarkably similar: an increasing metabolic acidosis was associated with brady-arrhythmia and progressive myocardial failure, which did not respond to resuscitative measures. All children developed lipaemic serum after starting propofol. These features are not usually associated with respiratory tract infections. No evidence was found of viral myocarditis, which was considered as a possible cause of death. CONCLUSION: Although the exact cause of death in these children could not be defined, propofol may have been a contributing factor.

Acidosis↗
PubMed1992

Neurotoxicity related to lithium and neuroleptic combinations? A retrospective review.

The question of toxic interactions resulting from combinations of lithium and neuroleptic drugs is largely based on anecdotal reports. We replicated the methods of Miller and Menninger (1987) who reported that 27% of manic patients on treatment with lithium and neuroleptics developed toxicity. We found no cases of neurotoxicity as defined in the earlier report. Pharmacologic mechanisms and differences in the clinical findings of the two studies are discussed.

Antipsychotic Agents↗
PubMed1991

Pharmacokinetics of neuroleptics.

Older studies on neuroleptic pharmacokinetics had problems in methodology and laboratory techniques. High performance liquid chromatography (HPLC) and combinations of techniques are used now. Clozapine levels are related to dose, age, sex, and smoking. Fluphenazine decanoate gives more predictable levels than oral, and 25 mg/2 weeks is associated with the lowest relapse rate. A therapeutic window with haloperidol is not well established; increased side effects at higher doses may account for the worsening seen. Half-lives much longer than previously quoted are now described. Children and the elderly are more susceptible to side effects of neuroleptics. Studies of the neuroleptic threshold and brain imaging indicate that doses used today are excessive. Nonresponders can distort dose effect relationships. Plasma levels are not useful routinely; they are of use in ruling out pharmacokinetic factors in nonresponse and when side effects are severe.

Antipsychotic Agents↗
PubMed1986

Isoflurane and halothane for outpatient dental anaesthesia in children.

A trial was undertaken in children to compare the use of halothane and isoflurane in outpatient dental anaesthesia. A wholly inhalation technique was chosen and nitrous oxide in oxygen was delivered from a Boyle's machine via a coaxial (Bain) breathing system and was supplemented with either halothane or isoflurane. Isoflurane produced significantly fewer arrhythmias than halothane but the induction of anaesthesia took longer and proved more difficult.

Adolescent↗
PubMed1986

The effect of halothane on cerebral electrical activity. An assessment using the cerebral function analysing monitoring (CFAM).

Recordings of cerebral electrical activity were obtained using the cerebral function analysing monitor from eight unpremedicated patients anaesthetised with increasing concentrations of halothane in oxygen. The amplitude of the processed EEG increased at one and decreased at two minimal alveolar concentrations. The frequency distribution of the weighted EEG signal showed a linear increase of delta activity with a corresponding decrease in beta activity with increasing concentrations of halothane.

Action Potentials↗
PubMed1985

The evaluation of domperidone and metoclopramide as antiemetics in day care abortion patients.

A randomised double-blind investigation was undertaken to assess the value of domperidone and metoclopramide as prophylactic anti-emetics in unpremedicated patients undergoing general anaesthesia for therapeutic abortion on a day care basis. Sixty patients were divided into three groups, and received, at induction, one of three drugs intravenously. The incidences of postoperative nausea and vomiting were 35% in the group receiving normal saline as placebo, 30% in the group receiving 10 mg domperidone and 25% in the group receiving 10 mg metoclopramide; these were not statistically significantly different. Furthermore, there was no statistically significant difference in the incidence of postoperative nausea and vomiting as influenced by age, weight, length of gestation, anaesthetic time and a history of nausea and vomiting during the pregnancy.

Abortion, Therapeutic↗
PubMed1984

Anaesthesia in Marfan's syndrome.

Thirteen patients with Marfan's syndrome who underwent surgery between 1968 and 1983 were studied to document the anaesthetic morbidity in this rare disorder. One of the 13 patients studied died intra-operatively, one died in the immediate postoperative period and one patient developed postoperative complications and further surgery was postponed indefinitely. This represents a high mortality/morbidity rate and the findings are recorded. The two deaths were unexpected and could not be explained.

Adolescent↗
PubMed1983

Rapid high-performance liquid chromatographic method for the measurement of atenolol in plasma using UV detection.

A rapid, selective and reproducible high-performance liquid chromatographic method has been developed for the measurement of the beta-adrenoceptor blocking drug atenolol in small (400 microliters) volumes of plasma. Following solid phase sample preparation using Bond-ElutTM mini-columns the compound is separated by high-performance column liquid chromatography on a microparticulate (6 microns) cyano column using acetonitrile--ammonium dihydrogen phosphate (4:96) containing triethylamine (0.25%, v/v) as the mobile phase, and the absorption of the column effluent is monitored at 224 nm. The practical limit of quantitation, based upon an assay volume of 400 microliters, is 25 ng/ml for atenolol. The average coefficient of variation is 3.1%.

Adult↗
PubMed1983

High-performance liquid chromatographic analysis of diltiazem and its metabolite in plasma.

A rapid, selective and reproducible high-performance liquid chromatographic method for the analysis in plasma of the calcium channel blocking agent, diltiazem, and one of its metabolites, deacetyldiltiazem is described. The method involves extraction with the methyl tert.-butyl ether of the drugs and the internal standard (verapamil), back-extraction into sulphuric acid and reversed-phase chromatography with UV detection. Over a concentration range of 10-1000 ng/ml the average coefficient of variation for diltiazem was 5.4% and for deacetyldiltiazem was 8.3%.

Benzazepines↗
PubMed1983

Efficacy, safety, and pharmacokinetics of a concentration-maintaining regimen of intravenous pirmenol.

A 3-stage, concentration-maintaining intravenous infusion regimen of pirmenol, a new antiarrhythmic agent, was tested for efficacy and safety in 8 subjects with chronic, stable premature ventricular beats. The regimen, which consisted of (1) a priming bolus of 50 mg over 2 minutes, followed by (2) a rapid loading infusion of 2.5 mg/min for 1 hour, and (3) a maintenance infusion of 0.25 mg/min, rapidly achieved and maintained stable plasma pirmenol levels from 0.94 to 2.75 micrograms/ml, during infusions lasting up to 48 hours. Therapeutic efficacy was evaluated during 4-hour infusions in 5 patients utilizing a randomized, double-blind, placebo-controlled study design. Pirmenol suppressed average premature ventricular beat frequency 93 +/- 6% compared with control values (p = 0.03). Pirmenol infusions were unassociated with toxicity. There were slight but significant increases in diastolic blood pressure, QRS duration, and corrected Q-T interval. No significant changes occurred in systolic blood pressure, heart rate, P-R interval, or laboratory variables. Pirmenol is a promising therapeutic agent that warrants further evaluation. The 3-stage infusion satisfactorily achieves and maintains therapeutic plasma pirmenol levels.

Adult↗
PubMed1982

Pirmenol kinetics and effective oral dose.

The oral form of pirmenol has not been administered to man. Pirmenol was given by mouth to eight patients with chronic, stable premature ventricular beats (PVBs) to determine effective dose and kinetics. The patients were evaluated with a dose-ranging protocol following by a double-blind, crossover, placebo-controlled study of doses that were effective during dose ranging. Oral doses of 150 to 250 mg induced at least 90% suppression of PVBs 18 of the 19 times they were administered during both protocols. During the double blind experiment, a single oral dose of pirmenol suppressed 95 +/- 8% PVBs/hr (mean +/- SD) for 3 consecutive hr, while placebo suppressed 4 +/- 42% PVBs/hr (P less than 0.01). a 90% or greater reduction in PVBs persisted for a median of 6 hr (range 1 to 8 hr). The range of plasma pirmenol concentrations associated with an at last 90% reduction in PVBs was 0.7 to 2.0 micrograms/ml. Median half-life (t1/2) was 9.3 hr (range 6.0 to 12.4) with 86.6 +/- 2.4% protein binding and 82.6 +/- 23.6% bioavailability. At peak drug level there was lengthening of the QTc interval (0.036 sec, P less than 0.05), but no change in heart rate, blood pressure, PR interval or QRS duration, or symptoms. In this single-dose study, pirmenol effectively reduced PVBs, has a relatively long t1/2, and was minimally toxic.

Administration, Oral↗