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J C Granry

Publications and source records attributed to J C Granry.

72 records · Page 4Linked to original sources

[Determination of thresholds of external cardiac pacing during anesthesia].

The efficacy of transcutaneous pacing was studied in 33 patients during general anaesthesia. The temporary pacing was effective in all cases. Stimulation thresholds ranged from 85 to 150 mA (mean : 110 +/- 17). In all 33 patients, external pacing was effective in producing a pulse without significantly reducing arterial pressure. Stimulation thresholds were only influenced by electrode position; age, weight, thoracic diameter and cardiothoracic ratio did not have any effect on them. No adverse effects of transcutaneous pacing were recorded. Transcutaneous pacing can be an alternative to transvenous right ventricular endocardiac pacing in the operating room in some circumstances.

Aged↗

[Anti-arrhythmia effects of magnesium salts. 4 cases].

Known since 1935, the antiarrhythmic effects of magnesium salts are periodically forgotten. They are illustrated here by 4 cases with entirely different clinical and biological features. Of unquestionable therapeutic value was the use of magnesium for the treatment of 2 episodes of severe ventricular extrasystoles with "torsades de pointe". These antiarrhythmic properties are observed whether blood magnesium levels are normal or low and cannot therefore be ascribed to correction of magnesium deficiency. Experimental data are in favour of interferences with transcellular ion flows. Magnesium is thought to ensure normal potassium gradient and also to reactivate the fast sodium channel inhibited by hypokalaemia. Above all, the magnesium ion appears to act as a calcium inhibitor, which would explain its antiarrhythmic properties irrespective of the state of magnesium body stores.

Adult↗

Thiopental pharmacokinetics under conditions of long-term infusion.

Thiopental was used in long-term infusion (3-4.5 mg . kg-1 . h-1 during 4-8 days) to protect the brain from injury following trauma. Thiopental plasma concentrations were measured during infusion (48 patients) and after infusion (14 patients) to determine the kinetics of the drug in continuous infusion. All mean values were mean +/- SD. Steady state concentrations (Css) were 31.8 +/- 10.7 mg/l for an infusion rate of 3.05 +/- 0.37 mg . kg-1 . h-1 and 48.9 +/- 14.6 mg/l for a rate of 4.2 +/- 0.3 mg . kg-1 . h-1. Corresponding steady state clearance decreased when Css increased, indicating possible saturation of the metabolic enzymatic system. Michaelis-Menten kinetics were confirmed by postinfusion data that give, for higher Css, a nonlinear decay of log C versus time. First-order kinetics were only obtained with Css below 30 mg/l. The maximum rate of elimination (Vm) was 1.76 +/- 1.15 mg . l-1 . h-1 (n = 11), and the Michaelis constant (Km) was 26.7 +/- 22.9 mg/l (n = 11). Hepatic enzyme saturation was between 35 and 85%. The volume of distribution at steady state was 4.35 +/- 1.83 l/kg (n = 11). Apparent half-lives of elimination were between 18 and 36 h at the end of infusion, and predicted terminal half-lives were 10.15 +/- 5.43 h (n = 11). Phases of burst-suppression were observed on electroencephalographic traces for concentrations greater than 40 mg/l. The authors' results suggest that a continuous infusion at a dose of 4 mg . kg-1 . h-1 induces EEG changes consistent with a near-maximum reduction in cerebral metabolism. Because of the thiopental Michaelis-Menten kinetics at doses above 4 mg . kg-1 . h-1, the authors suggest that thiopental plasma concentrations be measured and/or the drug effect be measured with the EEG to prevent excessive thiopental overdosage, causing a prolonged recovery time.

Adolescent↗

[Value of the intravenous route for the use of phenobarbital in asphyxiated full term newborn infants].

Phenobarbital (20 mg/kg) was given intravenously to asphyxiated full term neonates who were less than 48 hours old. Further doses were given for 4 days (5 mgs/kg/d). Plasma levels were within the therapeutic range from 5 to 36 hours after the first injection but the maintenance dose always resulted in overdose by 5th day. The exact maintenance dose needs to be determined.

Asphyxia Neonatorum↗

[The physiopathology and medical treatment of acute traumatic occlusion of the popliteal artery. The point of view of the anesthesiologist-resuscitator].

The acute occlusion of the popliteal artery involves: 1. A regional disease: muscular ischaemia with an increase of capillary permeability and oedema. The recovery of the circulation brings with it the formation of free radicals. 2. Sometimes, a general and metabolic illness complicates the muscular ischaemia. It associates to varying degrees: hypovolemic shock, metabolic troubles, acute renal failure, disseminated intravascular coagulation, infection. It can compromise the vital prognosis. The reanimation which completes the surgical treatment includes two stages: 1. The prehospital stage when the first imperative is to commit the patient to the vascular surgeon's care as soon as possible and in the best hemodynamic conditions. 2. The hospital stage when the therapeutic objectives are represented by: a) the treatment of hypovolemia; b) the curing of acute renal failure (bicarbonates 2 mmol.kg-1, hypertonic mannitol 1 g.kg-1; c) fight against infection; d) Heparin: 1 to 2 mg.kg-1 (if there is no counterindication); e) hyperbaric oxygen treatment in some situations. Despite the progress of reanimation, the initially intended amputation is subject to discussion in the following circumstances: crushing which in fact accomplishes an amputation, prolonged and complete ischemia lasting more than 10 to 12 hours, severe I.V.D.C., associated serious lesions (cranial traumatism, pelvis crushing).

Acute Disease↗

[Plasma concentrations of ornidazole in newborn infants and infants after iterative administration].

Ornidazole was administered for ten days to twelve hospitalized neonates at the same daily dose of 20 mg/kg either by one or two IV infusions. Minimum steady-state concentrations measured between the 4th and 10th day ranged from 7.8 to 17.3 (mean = 11.8 +/- 3.2 mg/l) for one daily infusion and from 10.9 to 26.6 (mean = 20.5 +/- 6 mg/l) for two infusions. These minimum concentrations were all above the minimum inhibitory concentration for the most clinically significant anaerobic bacteria. So the single daily administration of ornidazole at the dose of 20 mg/kg is sufficient to obtain therapeutic efficiency.

Bacterial Infections↗

[Pharmacokinetics of paracetamol in the cerebrospinal fluid in the elderly].

We investigated acetaminophen pharmacokinetics in CSF in twelve operated arteritics patients with continuous spinal anesthesia. Nine men and three women aged 77 +/- 7 years and weighing 66 +/- 15 kg entered in the study after expressing verbal informed consent. They received intravenously a single dose of acetominophen (equivalent to 1 g). Fifteen minutes to six hours after the intravenous injection, blood and CSF samples were withdrawn every thirty minutes, except during the second to the third hour were it was every fifteen minutes. Acetaminophen concentrations in blood and in CSF were assayed by HPLC. Acetaminophen was detected in the earliest samples (1.32 +/- 1.32 micrograms.ml-1) and then increased up to 8.16 +/- 3.04 micrograms.ml-1 at 186 +/- 56 minutes. From 135th to 345th minute, acetaminophen concentration in CSF stay at about 6 micrograms.ml-1, which is the duration of its maximal analgesic central effect.

Acetaminophen↗