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R Demeyere

Publications and source records attributed to R Demeyere.

10 recordsLinked to original sources

[Comparison of new cardiac agents using differential therapeutic criteria].

Positive inotropism, reduction in preload, and reduction in afterload induced by any cardiacum are not exactly quantified in humans, nor are the patients classified as to their respective requirements. Also, any of these drug activities change with the patient's instantaneous cardiac and hemodynamic functional state. One reason for incomplete knowledge is a shortage of methods which allow to assess the inotropic state of the myocardium. In 17 patients, age range 56-76 years (two females, 15 male), undergoing routine coronary surgery, informed consent was obtained for implantation of a needle transducer for measurement of wall force. At the end of coronary surgery, developed myocardial force and aorto-coronary bypass flow were measured electromagnetically. After control measurements, 0.03, 0.06 and 0.1 mg/kg enoximone were injected slowly (3 min per dose) into the aorto-coronary bypass. Eight to 18 h after surgery, and again 18-48 h after surgery, the following measurements were made, first as a control, and then after 1.5 mg/kg enoximone i.v.: aortic pressure (AoP), central venous pressure (CVP) and pulmonary artery pressure (PAP), cardiac output (CO), and heart rate (HR). Peripheral vascular resistance (TPR) was calculated. Developed force and its derivatives were recorded continuously. Immediately after recovery from cardioplegia a 0.19 mg/kg dose of enoximone injected over 9 min into the aorto-coronary bypass induced an increase in bypass flow of 64 +/- 30%. Mean arterial pressure (MAP) showed a fall 5 min after enoximon injection on both occasions. The values were 73 (+/- 3.7) to 67 (+/- 2.6) mmHg, and 83 (+/- 3.1) to 78 (+/- 2.8) mmHg, respectively. The increase obtained in cardiac output (CO) 6.0 (+/- 0.4) to 7.4 (+/- 0.7) l.min-1, and 6.2 (+/- 0.7) to 8.5 (+/- 1.3) l.min-1 was significant at 5 min and remained so at 30 min on both occasions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

The use of midazolam versus propofol for short-term sedation following coronary artery bypass grafting.

Midazolam and propofol were compared in an open randomized study for postoperative sedation during 12 h of mechanical ventilation in 40 patients following coronary artery bypass grafting. After an intravenous loading dose of midazolam (50 micrograms.kg-1) or propofol (500 micrograms.kg-1), a titrated continuous infusion was administered of midazolam (mean dose 38.1 micrograms.kg-1.h-1 (SEM 2.6)) or propofol (mean dose 909 micrograms.kg-1.h-1 (SEM 100)) together with a narcotic analgesic infusion. During mechanical ventilation midazolam and propofol produced a similar quality of sedation, but recovery (midazolam 66 min (SEM 16); propofol 24 min (SEM 7)) and weaning from the ventilator (midazolam 243 min (SEM 44); propofol 154 min (SEM 33)) where faster with propofol. In the 2 groups administration of an intravenous loading dose caused a significant decrease in mean arterial pressure but hemodynamic tolerance during maintenance infusion was good.

Aged

Autotransfusion during aorto-iliac surgery.

Red blood cell (RBC) quality and function during autotransfusion with the Solcotrans system were studied. Up to 64% (mean 999.5 +/- 310 ml) of the total volume of blood lost (mean 1895 +/- 707 ml) during operation in 10 patients undergoing elective abdominal aortic surgery was salvaged. No patient received homologous blood during surgery. Haemoglobin (Hb) and Haematocrit (PCV) values decreased but within acceptable limits. No evidence of DIC was found and renal function was unaffected. Mechanical and functional damage to the RBC was minimal and erythrocyte oxygen-carrying capacity was excellent. 2,3-DPGRBC concentration and RBC reduced glutathion were normal. The device was easy to handle and technical problems were not encountered. It was accurate in salvaging blood although the need for homologous blood was not entirely eliminated since four patients received homologous blood products in the postoperative period. No adverse clinical events occurred.

Aged

Cardioprotective effects of carnitine in extensive aortocoronary bypass grafting: a double-blind, randomized, placebo-controlled clinical trial.

The cardioprotective effects of carnitine were tested in patients undergoing multiple aortocoronary bypass grafting. Intermittent aortic cross-clamping at 28 degrees C was used. Mean total cross-clamping time was 30 +/- 11 min. Patients were randomized into three groups: a control group receiving placebo (group 1), a group pretreated with 3 g carnitine intravenously before cardiopulmonary bypass (CPB) (group 2), and a group pretreated with 6 g carnitine intravenously (group 3). The markers of myocardial ischemia included levels of adenosine triphosphate, its catabolites, and creatine phosphate in transmural left ventricular biopsy specimens taken at the beginning and end of CPB, as well as hemodynamic recovery during weaning from CPB and for the next 24 h. The intravenous infusion of carnitine (3 or 6 g) had no hemodynamic effect. At the end of CPB myocardial tissue levels of adenosine triphosphate and creatine phosphate did not differ significantly among the groups (P greater than 0.05). Recovery of cardiac function during weaning from CPB and for the following 24 h was similar in all three groups (P greater than 0.05). It is concluded that pretreatment with carnitine neither facilitates weaning from cardiopulmonary bypass in patients undergoing aortocoronary bypass surgery nor favorably affects hemodynamic function during the next 24 h.

Aged

Total I.V. anesthesia using a continuous etomidate infusion.

Total I.V. anesthesia was given to 20 patients using an Etomidate continuous infusion to maintain sleep, combined to Fentanyl analgesia, Droperidol, Pancuronium for muscular relaxation and artificial ventilation with an oxygen-air mixture. All these patients were carefully observed during and for several hours after the anesthesia and the results noted. With the Fentanyl dosages used in this technique, peroperative analgesia was frequently insufficient. More Fentanyl would probably be needed with the inherent dangers of prolonged postoperative depression.

Adult

Malignant hyperthermia.

Malignant hyperthermia is now recognized as a distinct entity in anesthetic practice and can be considered as a pharmacogenetic disease of obscure etiology occuring in man and pigs with a dominant inheritance. A close association with myopathy has been noted. Commonly used muscle relaxants or anesthetic drugs can act as triggering agents in genetically susceptible patients, who develop a real hypermetabolic state, characterized by a rapid rise in body temperature, muscular rigidity, tachycardia and tachypnoea, cyanosis and severe respiratory and metabolic acidosis, the lethality being about 60%. Other clinical, biochemical and histopathological features of this condition are described. The prevention and early diagnosis of this syndrome is very important. Therefore, it is necessary in the preanesthetic evaluation, to obtain information from the patient, with regard to previous anesthetic experiences, and to have a more exact anamnesis in patients with muscular diseases or with other members of the family under suspicion. Some screening methods are described. The prognosis of malignant hyperthermia depends on an early diagnosis. Although the incidence is, fortunately, small, this condition is sufficiently significant and acute in nature to require that anesthesiologist be aware of its clinical pathophysiology and prepared to recognize and treat it promptly. Therefore body temperature should be controlled continuously in all anesthetized patients, particularly in the younger age group and especially in those in which symptoms of muscle rigor have been observed particularly after application of succinylcholine and halothane. A regime of treatment is suggested, based on current concepts of the pathogenesis. It consists in establishing effective and rapid cooling, reversal of tissue hypoxia and correction of respiratory and metabolic acidosis and hyperkalemia. Specific therapy with dantrolene sodium may prove to be an answer to this serious problem.

Anesthetics