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B Debaene

Publications and source records attributed to B Debaene.

54 records · Page 3Linked to original sources

[Desflurane (I 653) and sevoflurane: halogenated anesthetics of the future?].

Sevoflurane is an halogenated methyl isopropyl ether. It is potent, non explosive and non flammable. It reacts with soda lime to form traces of a related ether which has not been shown to have any toxic effect on animals chronically exposed to it in a closed system. Induction of anaesthesia with sevoflurane is rapid and smooth, as predicted by a blood/gas partition coefficient of about 0.6 and an acceptable odour which allows the use of concentrations of up to 10%. Its MAC has been reported to vary between 1.7 and 2.3 vol %. Sevoflurane causes dose-dependent cardiovascular and respiratory depression. Its effect on the cerebral circulation is similar to that of isoflurane. The extent of biotransformation is similar to that of enflurane, but its low solubility and rapid elimination confine this to the period of inhalation. No toxic effects on the kidneys, liver and haematopoietic system have been found. Desflurane is a fluorinated methyl ether, structurally very similar to isoflurane. It is non flammable and non explosive at clinical concentrations. It is more stable in the presence of soda lime than any of the volatile anaesthetic agents available. This agent must be delivered with a thermostated vaporizer within a closed circle system, as its boiling point is 23.5 degrees C. Desflurane is less potent than isoflurane. Its MAC has been estimated to be about 7.2 vol % in man. Desflurane did not lead to any liver, lung or kidney injury in laboratory rats, even during hypoxia and enzyme induction. Desflurane undergoes little biotransformation, although the presence of volatile metabolites or covalent tissue-bound products cannot be excluded.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Inhalation↗

[Another failure in the attempt of definition of the indications to the resection of liver metastases of colorectal origin].

Many discordances can be found in the literature of the last ten years, about the definition of the main prognostic factors after resection of LM from colorectal cancers. Indications of liver resections depend on these prognostic factors. We prospectively enregistred the parameters of 97 patients which had undergone 119 hepatectomies from 1983 to 1990, and we have done a prognostic study. The mean number of resected LM was 2.3, nineteen patients had at least four LM, 22 patients had extrahepatic localization, and 16 had a 0-1 mm free margin. Only one patient died during the postoperative course. The overall five years survival was 33 +/- 8% and the disease free survival was 26 +/- 7%. Unfortunately none prognostic factor significantly influenced the survey in this series, and notably nor the staging of the primitive tumor, nor the synchronous or metachronous happening, nor the number of LM, nor the extrahepatic localizations, nor the free margin. We conclude that: 1) a greater number of patients and a more important follow-up could permit to define clinical or paraclinical prognosis factors but they will be only secondary prognosis factors; 2) it is necessary to prospectively study some new biologic, histologic and immunologic parameters in order to discover the fundamental prognosis factors.

Adult↗

Effects of ketamine, halothane, enflurane, and isoflurane on systemic and splanchnic hemodynamics in normovolemic and hypovolemic cirrhotic rats.

The effects of ketamine, halothane, enflurane, and isoflurane on systemic and splanchnic hemodynamics in cirrhotic rats that were either normovolemic or hypovolemic following hemorrhage were characterized. Rats received at random either ketamine (30 mg/kg iv, 1.5 mg.kg-1.min-1 iv), halothane, enflurane, or isoflurane (1 MAC). Conscious rats were considered the control group. Four weeks before hemodynamic studies bile duct ligation was performed in all rats to induce cirrhosis. Hemodynamic measurements were performed using the radioactive microsphere method 1 h after the onset of anesthesia and 30 min after hemorrhage. Anesthetized rat lungs were mechanically ventilated with room air. Before hemorrhage cardiac index was higher in conscious rats and in rats receiving isoflurane than in the other groups (P less than 0.001). Hepatic arterial blood flow was similar in conscious rats and in those receiving isoflurane or halothane and was higher than in those receiving ketamine or enflurane. The lowest splanchnic and portal venous tributary blood flows were observed in rats receiving enflurane. After hemorrhage cardiac index was significantly less than before hemorrhage in all groups, except in rats receiving enflurane. After hemorrhage portal venous tributary blood flow decreased significantly in all groups except in enflurane group. During halothane and enflurane anesthesia hepatic arterial blood flow and hepatic arterial fraction of cardiac output decreased (P less than 0.01) and they were maintained in the other groups. After hemorrhage hepatic arterial fraction of cardiac output in conscious rats was higher than in those receiving ketamine, halothane, or enflurane (P less than 0.05) and was similar to those receiving isoflurane.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Hepatic blood flow in humans during isoflurane-N2O and halothane-N2O anesthesia.

Hepatic blood flow (HBF) (assessed by plasma clearance and hepatic extraction of indocyanine green), cardiac index, and hepatic venous oxygen saturation were measured in patients before and after induction of anesthesia with thiopental, fentanyl, and N2O, and again during halothane (1 MAC)-N2O (n = 5) or isoflurane (1 MAC)-N2O (n = 6) anesthesia before the start of surgery. Induction of anesthesia decreased HBF and cardiac index. Before administration of volatile anesthetics, both groups had similar values of HBF, cardiac index, and hepatic venous oxygen saturation. During anesthesia cardiac index remained stable in both groups, whereas HBF increased significantly with isoflurane but did not change significantly with halothane. Hepatic venous oxygen saturation was also significantly greater during isoflurane than during halothane anesthesia. We conclude that isoflurane increases HBF in anesthetized patients and is associated with a higher hepatic venous oxygen saturation than is halothane.

Adult↗

Recovery from vecuronium neuromuscular blockade following neostigmine administration in infants, children, and adults during halothane anesthesia.

To determine whether neostigmine had different effects in pediatric patients during vecuronium neuromuscular blockade, the rate of recovery following neostigmine administration was compared in infants (n = 8), children (n = 10), and adults (n = 10) during nitrous oxide-halothane anesthesia. After induction of anesthesia, patients received 100 micrograms/kg of vecuronium. The EMG response of the adductor pollicis was monitored after train-of-four (TOF) stimulation of the ulnar nerve every 20 s. When the first twitch of TOF spontaneously recovered to 10% of control value, neostigmine was injected (40 micrograms/kg in adults, 30 micrograms/kg in infants and children). During the first few minutes following neostigmine administration, no differences were observed between the three groups. After the 8 min, recovery was more rapid in children than in infants and adults up to and including the 15th min. Ten minutes after neostigmine administration, the first twitch (mean +/- SD) reached 97 +/- 3%, 99 +/- 2%, and 97 +/- 5% of control value in infants, children, and adults, respectively; TOF ratio was greater in children (0.96 +/- 0.03) than in either adults (0.82 +/- 0.17) or in infants (0.83 +/- 0.14) (P less than 0.05). During the first minutes after neostigmine administration, the lack of difference in TOF recovery in the three groups suggests that neostigmine is the main factor of recovery. In contrast, the more complete recovery after the eighth minute in children could be due to the faster rate of spontaneous recovery from vecuronium induced neuromuscular blockade in children.

Adult↗

Interpleural analgesia with bupivacaine following thoracotomy: ineffective results of a controlled study and pharmacokinetics.

STUDY OBJECTIVE: To evaluate intrapleural analgesia with bupivacaine following partial pulmonary resection and to determine pharmacokinetic parameters of bupivacaine with epinephrine. DESIGN: Prospective, randomized study. SETTING: Thoracic surgical clinic of a university-affiliated general hospital. PATIENTS: Eighteen consecutive patients (13 men, 5 women) scheduled for pulmonary surgery by posterolateral thoracotomy. INTERVENTIONS: Bupivacaine was administered through an intrapleural catheter as a bolus dose of either 40 ml of 0.25% bupivacaine with epinephrine (0.5 mg per 100 ml of solution) (n = 10) or 20 ml of 0.5% bupivacaine with epinephrine (0.5 mg per 100 ml of solution) (n = 8) up to three times daily for a maximum time of 4 days. MEASUREMENTS AND MAIN RESULTS: Subjective evaluation of pain was performed using the visual analog scale (VAS) before and after each injection by response to spontaneous pain, coughing, deep breathing, and incision palpation. Maximum peak concentration (C Max) and maximum time to reach the peak concentration (T Max) were assessed after the first and last injections. Although VAS pain score decreased significantly, pain relief was not sufficient. C Max and T Max after the first and last injections were not significantly different between the two groups. In each group, C Max after the last injection was significantly higher than after the first injection. CONCLUSIONS: Intrapleural analgesia conducted with 40 ml of 0.25% bupivacaine with epinephrine or 20 ml of 0.5% bupivacaine with epinephrine was insufficient for pain, despite high plasma bupivacaine concentration.

Acetaminophen↗