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P Stieglitz

Publications and source records attributed to P Stieglitz.

At least 19 recordsLinked to original sources
PubMed1992

[Pharmacokinetics of methohexital given by constant rate intravenous infusion].

The pharmacokinetic characteristics of a constant rate methohexitone infusion were studied in young ASA 1 patients undergoing maxillofacial surgery. They were randomly assigned to two groups; group M patients (n = 7) were given 9 mg.kg-1.h-1 of methohexitone for one hour, and group MF patients (n = 7) 9 mg.kg-1.h-1 of methohexitone with 7 micrograms.kg-1.h-1 of fentanyl, also for one hour. Blood samples for determining methohexitone concentrations were obtained at various times, from before the start of the methohexitone infusion up to 19 h afterwards. In twelve patients, a two-compartment model was appropriate to characterize the decrease of methohexitone concentration; for the other two (one in each group), a three-compartment model was applied. There were no statistically significant differences between the two groups. Elimination half-life in group M was 3.22 +/- 1.96 h, and total plasma clearance 8.54 +/- 2.8 ml.kg-1.min-1. The wide variations in pharmacokinetic parameters between subjects may explain some unpredictable variations in duration of action of methohexitone. Fentanyl did not modify methohexitone pharmacokinetics, which remained of the first order. However, it potentiated the barbiturate's action: extubation was only possible after stopping the infusion for 39.4 min +/- 22 min in group MF, and 15.4 min +/- 6 min in group M (p less than 0.01). At that time, plasma concentrations were respectively 3.12 +/- 0.99 mg.l-1 (group MF) and 5.71 +/- 2.09 mg.l-1 (group M), (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Comparative effects of halothane associated with verapamil and ischaemia on myocardial metabolism in isolated perfused rat hearts.

The association of verapamil with halothane causes ischaemic-like myocardial dysfunction. Using an isolated rat heart model perfused with a radiolabelled fatty acid (123I-labelled iodohexadecenoic acid) as a sensitive marker of ischaemia this study investigated whether or not this dysfunction is of ischaemic origin. Hearts were perfused with a control solution or with solutions containing either 1% of halothane or 150 ng ml-1 of verapamil or the association of 0.75% halothane + 120 ng ml-1 verapamil. The ischaemic group was perfused at a reduced perfusion rate (-50%). Intracellular fate of IHA was assessed, and its esterification ratio computed. Ischaemia and the drugs induced a similar depression of haemodynamics. The esterification ratio in the ischaemic group was significantly higher (0.723 +/- 0.04) than in controls (0.0526 +/- 0.03) and than in the treated groups: halothane (0.533 +/- 0.06), verapamil (0.411 +/- 0.027) or the association halothane+verapamil (0.408 +/- 0.05), suggesting a non-ischaemic origin for the dysfunction caused by halothane-verapamil.

Animals↗
PubMed1992

Exertional heatstroke and muscle metabolism: an in vivo 31P-MRS study.

An impairment of muscle energy metabolism has been suggested as a predisposing factor for, as well as a consequence of exertional heatstroke (EHS). Thirteen young men were investigated 6 months after a well-documented EHS using 31Phosphorus Magnetic Resonance Spectroscopy (31P-MRS). The relative concentrations of ATP, phosphocreatine (PCr), inorganic phosphate (Pi), phosphomonoesters (PME), and the intracellular pH (pHi) were determined at rest, during a graded standardized exercise protocol (360 active plantar flexions) and during recovery. Also the leg tissue blood flow was determined by venous occlusion plethysmography during the MRS procedure. Sixteen age-matched healthy male volunteers served as control group. In resting muscle, there were no significant differences between the groups as regards pHi, Pi/PCr, and ATP/PCr+Pi+PME ratios. During steady state exercise conditions, effective power outputs were similar for both groups at each level of exercise: 20, 35, and 50% of maximal voluntary contraction (MVC) of the calf muscle. No significant differences were shown between the two groups in Pi/PCr, pHi, or changes of leg blood flow at each level of exercise. At 50% MVC, Pi/PCr was 0.48 +/- 0.08 vs 0.47 +/- 0.05 (P = 0.96), pHi was 6.94 +/- 0.03 vs 6.99 +/- 0.02, respectively (P = 0.13). Finally, the rate of PCr resynthesis during recovery was not significantly different between the two groups: t1/2 PCr = 0.58 +/- 0.07 vs 0.50 +/- 0.05 min, respectively (P = 0.35). Therefore, no evidence of an impairment of muscle energy metabolism was shown in the EHS group during a standardized submaximal exercise using 31P-MRS performed 6 months after an EHS.

Adenosine Triphosphate↗
PubMed1989

[Management of a patient with malignant hyperthermia susceptibility during anesthesia and daily living].

Death from malignant hyperthermia (MH) still occurs in France. However, anaesthesia of the MH susceptible (MhS) patient is quite possible without any more risk than for patients who are not MhS. Guidelines have been worked out: "trigger" drugs such as volatile anaesthetics (halothane, enflurane, isoflurane) and depolarizing muscle relaxants must be imperatively avoided; "non-trigger" drugs should be used, such as nitrous oxide, barbiturates, benzodiazepines, propofol, opiates, non-depolarizing muscle relaxants, amide or ester local anaesthetics at the usual doses without adrenaline. Moreover, dantrolene should be available in all hospitals, 12 bottles being a minimum at hand, or, better, 30 (about 10 mg.kg-1). In some cases, such as emergencies, an unprepared operating theatre, or an unprepared ventilator, the patient should be premedicated with 2.5 mg.kg-1 dantrolene intravenously. The ventilator, the circuit and the operating theatre should not contain any trace of halogenated vapour. The usual parameters, as well as temperature and expired CO2 concentration, should be closely monitored. MhS patients must also be given counselling. This includes explanations about MH, its genetic features, the main laboratory tests used to detect susceptibility, as well as advice about lifestyle, the use of drugs other than general and local anaesthetics, and a discussion concerning the association of MH with other diseases. This counselling is not always easy to provide, because many answers are not, as yet, definitive.

Activities of Daily Living↗
PubMed1988

[Registration of peranesthetic cases of malignant hyperthermia in France. An update].

Sixty-two suspected crises of anaesthetic malignant hyperthermia (MH) were collected between 1969 and 1988 by a retrospective inquiry which lasted four years. 33 patients (53%) died whilst 29 survived. 20 cases were confirmed to be MH, either directly or indirectly by way of muscle biopsy and halothane and caffeine contracture tests carried out according to the European MH group protocol by two laboratories. This group included 11 of the deaths, one family member of whom, at least, is sensitive (MHS), 7 MHS survivors and 2 survivors too young to undergo muscle biopsy but belonging to MHS families. 21 cases were highly suspect of MH: 15 of the deaths which occurred in a typical way, and 6 patients of three different families who have suffered from anaesthetic deaths which, clinically, suggested MH. Another 15 were possible MH cases, all survivors, including one case of Steinert's disease and a brother of a case of central core disease. 2 cases were still being debated, because they had equivocal results for the caffeine test (MHEc); the last 4 had negative muscle biopsies and were excluded. 33 close relatives of the MH patients were diagnosed as MHS. 44 others were found to be free from the genetic predisposition. It was strongly recommended to yet 11 others that they carry the MHS card because they were MHEc. The clinical, surgical and anesthetic pictures were always as described in the literature. The anaesthetic protocols included inhalational agents in 90% of cases; these were combined with suxamethonium in 55% of cases. Dantrolene was only used in 32% of cases, and then at inadequate doses and very often too late; this probably explains the large number of treatment failures. The number of severe forms of MH was also very high in this series (70%). The need to increase the means of prevention and screening for MH in France is stressed.

Adolescent↗
PubMed1987

[Comparison of the clinical effects of propofol and methohexital in induced abortion].

The clinical effects of propofol and methohexitone were compared in a group of 59 women undergoing abortion under general anaesthesia. At induction, the premedicated patients were given 2.5 mg . kg-1 propofol or methohexitone, followed by 1 mg . kg-1 fentanyl; if necessary, extra bolus doses of hypnotic were given. Hiccups and other movements were more frequent with methohexitone. There was no difference between the two groups as for injection pain and apnoea. The quicker recovery with propofol, with a mean of 2 min less, even when extra doses were given, could be explained by the pharmacokinetics of the drug. However, the quality of recovery in either group was satisfactory for short-length anaesthesia.

Abortion, Induced↗
PubMed1984

[Pollution of operating rooms with volatile and gas anesthetics. Methods of prevention].

Gaseous anaesthetic pollution in operating theatres has been known since as far back as 1924. Following Vaisman and Cohen's epidemiology studies, health organizations have been involved in this professional concern. Halogenated vapours and nitrous oxide anaesthetic pollution have been accused of doubling the abortion rate and of moderately increasing the number of congenital abnormalities in the offsprings of anaesthetists. The liver and nervous system are also likely targets for anaesthetic pollution. Animal or cell culture experimental studies concerning pathological consequences of exposure to nitrous oxide or halogenated vapours give conflicting results and are not conclusive. The pollution rate is measured by chromatography and spectrophotometry. 25 ppm nitrous oxide and 2 ppm halothane are the upper limits allowed for air contamination. Total intravenous anaesthesia, closed circuits, draining away expired gases can prevent such pollution, but these techniques do have drawbacks. Pollution prevention is rather simple, moderately expensive and comforting for operating room staff.

Air Pollution↗
PubMed1983

[Exposure to anesthetic gases: risk and prevention].

Several studies published during the last fifteen years seem to demonstrate that major risks, i.e. congenital malformations in the offspring and increased rate of spontaneous abortions, are associated with occupational exposure to anesthetic gases (halothane and nitrous oxide) in operating rooms. In view of the severity of the potential risk, we have: 1) analyzed risk factors in the light of epidermiologic and experimental studies; 2) determined the threshold levels of air pollution for these risk factors; 3) analyzed the situation in the Grenoble Hospital and the means of dealing with it.

Abnormalities, Drug-Induced↗
PubMed1983

[Respiratory obstruction during anesthesia in cases of mediastinal malignant lymphoma].

Three cases of asphyxia at the beginning of general anaesthesia for mediastinoscopy or biopsy of adenopathy are described in patients with malignant lymphoma. One of them died in spite of endobronchial intubation, artificial ventilation and steroids. The two others recovered when specific chemotherapy was added to the same symptomatic treatment. The risk of respiratory obstruction seems higher in non-Hodgkin than in Hodgkin lymphomas. This kind of obstruction is not relieved by an antiasthmatic therapy. Pulmonary lymphatic filtration may be hindered in case of mediastinal lymphoma, especially during anaesthetic induction, and pulmonary interstitial congestion may occur impeding gas propagation. Specific chemotherapy according to the histological type of the tumour may relieve the compression and respiratory obstruction in a few hours.

Adolescent↗