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Biomedical subjects

G Desch

Publications and source records attributed to G Desch.

At least 19 recordsLinked to original sources
PubMed1992

Reversal of electrophysiologic and hemodynamic effects induced by high dose of bupivacaine by the combination of clonidine and dobutamine in anesthetized dogs.

The ability of clonidine and dobutamine to correct bupivacaine-induced cardiac electrophysiologic and hemodynamic impairment was evaluated in an experimental electrophysiologic model on closed-chest dogs. Five groups (n = 6) of pentobarbital-anesthetized dogs were given atropine (0.2 mg/kg IV). Group 1 was given a saline solution; all other dogs were given bupivacaine (4 mg/kg IV) over a 10-s period. Group 2 was given only bupivacaine. Group 3 was given clonidine (0.01 mg/kg IV) over a 1-min period. Group 4 was given a dobutamine infusion at 5 micrograms.kg-1.min-1. Group 5 was given the combination of clonidine and dobutamine. Bupivacaine induced bradycardia, prolonged atrioventricular conduction time (PR interval), atrioventricular node conduction time (AH interval), His-Purkinje conduction time (HV interval), and QRS duration. Bupivacaine decreased left ventricular (LV) dP/dt max and increased LV end-diastolic pressure (LVEDP). Clonidine improved QRS duration and HV interval but enhanced AH interval, bradycardia, and hemodynamic depression induced by bupivacaine. Dobutamine infusion improved LV dP/dt max but did not modify bupivacaine-induced ventricular electrophysiologic impairment. The combination of clonidine and dobutamine corrected not only the electrophysiologic impairment induced by bupivacaine but also the hemodynamic depression. As the HV interval and the QRS duration could be correlated with ventricular conduction velocities, we conclude that (a) clonidine reversed the slowing of ventricular conduction velocities induced by bupivacaine, and (b) the combination of clonidine and dobutamine was able to correct the cardiac disturbances induced by bupivacaine in anesthetized dogs.

Animals↗
PubMed1990

[Do beta adrenergic receptor blockaders increase bupivacaine cardiotoxicity?].

Bupivacaine is known to impair the electrophysiology of the heart as well as haemodynamic parameters. Administration of calcium channel blockers prior to bupivacaine enhances its cardiotoxicity. This study assessed the effects of bupivacaine at toxic dose in dogs with previous beta-adrenergic receptor blockade. It included 12 dogs anaesthetized with thiopentone, allocated in a control group (n = 6) receiving a bolus of bupivacaine (4 mg.kg-1) and a study group (n = 6) treated with the sequence propranolol (0.2 mg.kg-1) and bupivacaine (4 mg.kg-1), 15 min later. Infranodal conduction (HV conduction times and QRS durations) was worsened in both groups. Previous propranolol administration had no potentiating effects on these parameters. Conversely the latter was responsible of a greater decrease in heart rate, and increase in atrio-ventricular conduction time (77.9% vs 18.7%, p less than 0.05), as well as a more severe hypotension. Moreover, 3 out of the 6 animals in the study group suffered a cardiac arrest between the 5th and the 10th min. It is concluded that in anaesthetized dogs the cardiac and circulatory effects of a toxic dose of bupivacaine are increased in case of preexisting blockade of beta adrenergic receptors.

Adrenergic beta-Antagonists↗
PubMed1989

[C-reactive protein in inflammatory articular diseases: comparison of concentrations in blood and synovial fluid].

We evaluated the diagnostic value of measuring C-Reactive Protein (CRP) in blood and in synovial fluid for the detection of inflammatory articular diseases in 154 patients. High concentrations of CRP in blood were found in microcrystalin arthritis, polymyalgia rheumatica and Horton's disease. Our results show a good correlation between CRP and erythrocyte sedimentation rate for ankylosing spondylitis (p less than 0.01), systemic lupus erythematosus (p less than 0.01), rheumatoid arthritis (p less than 0.05), polymyalgia rheumatica and Horton's disease (p less than 0.05). The CRP measurement in blood did not separate seropositive versus seronegative rheumatoid arthritis, systemic lupus erythematosus versus rheumatoid arthritis and treated versus non-treated rheumatoid arthritis. There was a good correlation between CRP concentration in blood and in synovial fluid but the concentration was lower in synovial fluid than in blood (p less than 0.01). Then, the CRP measurement in synovial fluid does not have a higher diagnostic value than in blood.

Aged↗
PubMed1989

Fibronectin is unsuitable as a tumor marker in pleural effusions.

We studied 75 patients with nonmalignant pleural effusions (50 with pneumopathy, 16 with pulmonary tuberculosis, and nine with congestive heart failure) and 33 patients with malignant pleural effusions. We selected 105 mg/L as the most suitable cutoff concentration of fibronectin for distinguishing between the two groups. We found high concentrations of fibronectin in 21 of the 33 patients with malignant pleural fluid but also in 37 of the 75 patients with nonmalignant pleural fluid. Evidently, measuring fibronectin in pleural fluid will not help in differentiating nonmalignant from malignant pleural fluids (diagnostic accuracy: 55%).

Adult↗
PubMed1988

Epidural analgesia with a bupivacaine-fentanyl mixture in obstetrics: comparison of repeated injections and continuous infusion.

We compared the efficacy and side-effects of continuous infusion versus repeated injections of epidural bupivacaine-fentanyl during labour. Forty-four parturients were randomly distributed into two groups balanced for population size, morphology and parity. Analgesia was begun at the same stage of labour with a mixture of 20 ml 0.25 per cent plain bupivacaine and 2 ml (100 micrograms) fentanyl. In Group I the initial dose ranged from 8-12 ml as a function of height; an injection of the same dose was repeated immediately upon recurrence of pain. In Group II, after an initial dose of 5-7 ml, a continuous infusion of 3 ml.h-1 was begun, and continued until full dilatation. Analgesia was rated using a pain scale; effects on maternal blood pressure, respiratory rate and neonatal status were noted. Bupivacaine and fentanyl assays were carried out on maternal venous blood in 30 parturients during the course of labour. There was a longer latency to onset of analgesia in Group II (approximately five minutes), followed by a more constant degree of analgesia. This better analgesia cannot be accounted for by a difference in dosage; doses were significantly lower in Group II, despite the fact that labour was of the same duration. The course of labour, and maternal and neonatal status were comparable in the two groups. Assays showed no difference in bupivacaine blood concentrations between the two groups nor signs of drug accumulation. The constant infusion technique is advantageous since it provides a more regular degree of analgesia with lower doses than those required for patients having repeated injections.

Adult↗
PubMed1988

[Plasma fibronectin: influence of age and sex].

The aim of this study was to determine, first, the effect of sex and age on the results of plasma fibronectin (Fn), and also the possible influence of the gestational age. The plasma Fn concentrations are higher in men than in women only in a range of 15-29 years old. The age dependence is very strong on plasma Fn levels; it practically double during life. The Fn concentrations according to age increase exponentially in men, linearly in women. The influence of gestational age is effective when it is less than thirty one weeks. Then, the Fn concentrations are significantly lower than in healthy newborn infants.

Adolescent↗
PubMed1985

Bromocriptine inhibition of hyperprolactinemia during surgery.

The material included two groups of 10 women undergoing diagnostic laparoscopy. General anesthesia was administered by injection of 0.1 mg fentanyl followed by infusion of propanidide-succinylcholine. The control group received no medication prior to surgery, whereas patients in the experimental group were given 5 mg bromocriptine per os. Blood samples for prolactin determinations were drawn as the patients were placed on the operating table and immediately following surgery. The association of anesthesia and surgery caused prolactin levels to rise from 10.9 +/- 3.5 to 168 +/- 18.7 ng . ml-1 in the control group (p much less than 0.001) and from 3.5 +/- 0.5 to 7.5 +/- 1.1 ng . ml-1 in the test group (p less than 0.001). A significant difference was noted between the two groups for their pre- and postoperative levels and prolactin response (p less than 0.05, p much less than 0.001 and p much less than 0.001, respectively). The proposed protocol successfully suppresses prolactin increase during surgery and constitutes a useful tool for investigating hyperprolactinemia and its consequences during this same time. Possible applications include in vitro fertilization and studies on prolactin receptor-bearing tumors.

Anesthesia, Intravenous↗
PubMed1982

Effect of acetate on ketogenesis during hemodialysis.

The concentration of plasma acetate, glucose, and ketone bodies were determined for both venous and arterial blood before and at the end of dialysis with an acetate-containing dialysate. We also determined lactate and pyruvate levels in arterial plasma. The results obtained in the same patients were compared when dialysis were done with or without glucose and discussed in terms of hormonal changes (insulin, glucagon). Arterial plasma acetate (p less than 0.001) and ketone body levels (p less than 0.05) increased significantly during dialysis both with glucose and without glucose (p less than 0.001 in both cases). Higher end-dialysis arterial levels were found for the latter set of glucose-free dialysis (p less than 0.05 and p less than 0.001, respectively, for acetate and ketone bodies), and a correlation was established between end-dialysis arterial concentrations of acetate and ketone bodies. This suggests high consumption of both endogenous and exogenous acetate to feed ketogenesis. This is concurrent with decreased insulin and high glucagon levels. Under these conditions, plasma accumulation of ketone bodies would facilitate an indirect elimination of acetate by the dialyzer (about 10% of the acetate load). Our results suggest that hormone variations during glucose-free dialysis which promote fatty acid oxidation and ketogenesis from acetyl groups hinder acetate-dependent lipogenesis.

3-Hydroxybutyric Acid↗
PubMed1981

[Pharmacokinetics of local anesthetics].

This article first looks at the pharmacokinetics of local anesthetic agents injected intravenously, and then looks at the possible practical applications of this technique: the choice of a local anesthetic agent as a function of its toxic side effects, the use of lidocaïne in local and regional intravenous anesthesia, and the treatment of cardiac rhythm disorders. Finally the article envisages the pharmacokinetics of local anesthetic agents used in local-regional anesthesia. This depends on the following factors: the site of injection, the dosage, the speed of injection, the possible addition of adrenalin and the nature of the local anesthetic itself. On the basis of a personal study the authors underline the difficulty of being precise in the pharmacokinetics of local anesthetic agents injected by the peridural route continuously or discontinuously.

Anesthesia, Conduction↗
PubMed1981

[Rapid simultaneous assay of the principalamide-type local anesthetics by gas-liquid chromatography].

This method can assay simultaneously, using 300 microliters of plasma, of the three principle local anesthetic agents used by peridural injection for post-operative anesthesia and analgesia: xylocaïne, etidocaïne, bupivacaïne. The assay method consists of three steps: (a) the addition of an internal calibrating agent (mepivacaïne). (b) defecation using trichlorocetic acid. (c) alcalinization of the supernatent (pH 11), extraction with dichloromethane and concentration at room temperature of the organic phase. (d) chromotography using an SE 30 or OV 17 impregnated column. The method is sensitive between 0.37 mumoles per l-1 (0.1 microgram . ml-1) and the coefficient for the mean deviation is 10.9% for concentration between 0.37 mumoles 1-1 and 75 mumole1-1 (0.1 microgram . ml-1 and 20 micrograms . ml-1). The correspondence of the figures recorded in this large concentration range without any change in the technique means that the kinetics of the plasma concentrations before and after peridural injection can be followed. The results obtained by gas liquid chromatography for the assay of lidocaïne were compared in 115 different plasma samples with concentrations obtained by an immuno enzymatic method ("EMIT") fitted to a centrifuge analyser. The correlation coefficient between the two methods was: (r = 0.95 with y = 0.09 x +0.25 microgram . ml-1 implying the absence of any interference and the specificity of the two methods. The columns also separate in 20 minutes the two main metabolites of lidocaïne: monoethylglycinexylidide (M.E.G.X.) and glycinexylidide (G.X.). These results demonstrate that continuous peridural injection of lidocaïne produces a high plasma concentration without any clinical toxic phenomena.

Anesthetics, Local↗
PubMed1980

[Decrease in BSP clearance during epidural anesthesia at a constant flow rate. Clinical implications].

The fractional clearance K1 of bromsulphthalein was measured in twelve surgical patients at an interval of a least 48 hours. The first measurement was performed pre-operatively and the second postoperatively 24 hours after the operation, whilst the patients were receiving analgesia by the epidural injection of lignocaine at a constant flow rate. Between the two determinations there was a fall in BSP clearance of 25 +/- 11 p. 100 (range: -8 and -40 p. 100) P less than or equal to 0.0001. The clinical implications are discussed on the basis of concrete examples.

Adult↗
PubMed1980

[Comparison of postoperative blood levels of prolactin and somatotropin after two methods of anesthesia].

Prolactin and somatotrophin were measured during the postoperative period in two series of 15 patients after gynaecological surgery. Samples were collected for four days at the same times during the 24 hours period. The anesthetic given in the first group was a neuroleptanalgesia of dextromoramide-droperidol type followed by postoperative analagesia using a noramidopyrine compound. In the second group, epidural anaesthesia was given, followed postoperatively by the injection of lidocain at constant rate interrupted between the final two samples. In the neuroleptanalgesia group, from a basal levels of 11 micrograms.l-1, prolactin rose to 22 micrograms.l-1 on the evening after surgery (p less than 0.001) to subsequently stay on a plateau between 6 and 8 micrograms.l-1 (p less than 0.025 to p less than 0.005). From a basal level of 2.8 micrograms.l-1, somatotrophin rose to 9 micrograms.l-1 (p less than 0.05) then fell progressively from 7.5 to 2 micrograms.l-1 (NS on D1, D2, D3). In the epidural group, from a basal level of 13.5 micrograms.l-1, prolactin rose to 23 micrograms.l-1 on the evening after surgery (NS) to fall sharply on D1 to 5.6 micrograms.l-1 (p less than 0.01) and then follow a plateau on D2 and D3 of the order of 11 to 12 micrograms.l-1 (NS). From a basal level of 1.9 micrograms.l-1, somatotrophin rose to 10 micrograms.l-1 (p less than 0.001) to fall again to 4.5 micrograms.l-1 on D1 (p less than 0.01) and to 2 micrograms.l-1 on D2 and D3 (NS). Comparison of these two groups showed a difference only on D2 with regard to somatotrophin (p less than 0.05) and on D2 and D3 with regard to prolactin (p less than 0.025 and p less than 0.05). These results are discussed. They do not indicate any fundamental difference in the endocrine response to aggression in relation to the two types of anaesthetic studies.

Anesthesia↗
PubMed1979

[Postoperative analgesia by constant flow injection of lignocaine in obstetrical and gynecologic surgery].

154 surgical patients were given post-operative analgesia by peridural injection at a constant flow in the post-operative period after obstetric or gynecological surgery. These patients received 536.2 +/- 105.3 mu mol.h-1 (145.2 +/- 28.5 mg.h-1) of lignocaine for 46.97 +/- 15.56 h through a catheter omserted between L1-L2. The drug was given in concentrations which varied between: 27.7 to 18.5 m mol.l-1 (0.75 to 0.50 p. 100) depending on the age; and the volume varied between 17.5 to 30 ml.h-1 depending on the height. Satisfactory analgesia in 87 p. 100 of cases allowed all supplementary analgesia to be stopped. The only significant hemodynamic effect was a slight tachycardia (+ 15 p. 100). Two undesirable side effects were noted: a transitory but well-defined (type 2 or 3) motor paralysis, and an accumulation of plasma lignocaine (40 mu mol.l-1 (1.1 microgram.ml-1) at 48 h).

Analgesia↗
PubMed1978

Plasma acetate levels during hemodialysis.

Before dialysis, acetate levels in hemodialyzed patients (0.27--1.1 mmol/1) were more dispersed than in normal subjects (0.20--0.65 mmol/l) and the mean value of plasma acetate was slightly higher (0.52 mmol/l versus 0.31 mmol/l). Though dialysis conditions were almost identical, the acetate kinetics during hemodialysis were very different: in most subjects, plasma acetate concentrations reached a "plateau" (mean value 5.6 mmol/l) whereas in others a continuous rise was observed, suggesting that with patients having chronic renal failure there were important individual or occasional differences in the ability to metabolize acetate. The acetate loads per minute (or mass transfers) were calculated from the blood compartment with plasma values (plasma flow and concentrations), rather than from the dialysate and using the combined calculations (plasma and whole blood values). The results ranged between 2.4 and 4.1 mmol/min. A very important and rapid fall in arterial acetate concentrations occurs in the first 20 min after the end of the dialysis and proves the rapid turnover of the acetate in man.

Acetates↗