ISSN:
1432-055X
Keywords:
Schlüsselwörter (S)-Ketamin
;
Ketamin-Razemat
;
Midazolam
;
Endokrine Streßreaktion
;
Aufwachverhalten
;
Key words (S)-ketamine
;
Racemic ketamine
;
Midazolam
;
Endocrine stress response
;
Recovery
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Description / Table of Contents:
Abstract Clinically used ketamine is a racemic mixture of two isomers, (S)- and (R)-ketamine, in equal amounts. Previous investigations showed the anaesthetic potency of (S)-ketamine to be three times higher than that of (R)-ketamine. The aim of this study was to compare the effects of (S)-ketamine/midazolam and racemic ketamine/midazolam on endocrine and cardiovascular parameters, recovery, and side effects in unpremedicated patients during knee surgery. Methods: 41 patients scheduled for elective knee surgery were investigated in a prospective, double-blind, and randomised design. For induction of intravenous anesthesia, patients received 0.1 mg/kg midazolam, 0.003 mg/kg atropine, 1 mg/kg (S)-ketamine or 2 mg/kg racemic ketamine, respectively. For tracheal intubation, 1 mg vecuronium and 1.5 mg/kg suxamethonium were injected. After intubation and relaxation with a total dose of 0.1 mg/kg vecuronium, a continuous infusion of 0.5 mg/kg/h (S)- or 1 mg/kg/h racemic ketamine was administered throughout the surgery. In addition, 0.05 mg/kg/h midazolam was infused continously in both groups throughout surgery. Ventilation was performed with N2O/O2 (FiO2 0.3). Blood samples were taken using a central venous line fivetimes before induction as well as during and after surgery for analysis of adrenaline, noradrenaline (by high-pressure liquid chromatography with electrochemical detection), anti-diuretic hormone (ADH), adrenocorticotropic hormone (ACTH), and cortisol (by radioimmunoassay). In addition, systolic and diastolic arterial pressure (SAP, DAP), heart rate (HR), and arterial oxygen saturation were measured. The time intervals between the end of ketamine and midazolam infusion and the return of consciousness and orientation were recorded. The incidence and quality of dreams and other side effects were reported by the patients. Results: Biometric data of the groups were comparable. Plasma adrenaline and noradrenaline did not change significantly during anaesthesia. ADH increased significantly (p〈0.05) after skin incision in both groups. ACTH and cortisol increased in both groups significantly during the course of anaesthesia. SAD, DAD and HR increased significantly after induction of anaesthesia. Recovery was not improved after administration of (S)-ketamine compared to the racemate. No intraoperative awareness and no negative dreams were reported. Conclusions: Increases in SAP, DAP and HR and insufficient reduction of the stress response with respect to ACTH and cortisol seem to require a premedication, which reduces ACTH secretion. Because of the significant reduction in quantitative drug load, (S)-ketamine offers a clinical advantage compared with currently used racemic ketamine.
Notes:
Zusammenfassung Zum prospektiven, doppelblind-randomisierten Vergleich von (S)-Ketamin und Ketamin-Razemat wurden endokrine Streßreaktionen sowie das Kreislauf- und Aufwachverhalten unprämedizierter Patienten während orthopädischer Kniegelenkeingriffe in intravenöser Anästhesie unter zusätzlicher Verwendung von Midazolam, Vecuronium und Lachgas untersucht. Patienten: Es wurden 41 Patienten in die Studie aufgenommen; davon gehörten 21 Patienten zur (S)-Ketamin- und 20 Patienten zur Razematgruppe. Die Kollektive unterschieden sich hinsichtlich der Alters- und Geschlechtsverteilung nicht signifikant. Die Messungen der endokrinen Streßparameter (Adrenalin, Noradrenalin, ADH, ACTH und Cortisol) erfolgten an 5 Meßzeitpunkten vor Einleitung der Narkose bis zur räumlichen Orientierung. Blutdruck, Herzfrequenz und periphere Sauerstoffsättigung wurden im Untersuchungszeitraum alle 5 min und der zentrale Venendruck alle 15 min dokumentiert. Ergebnisse: In beiden Kollektiven kam es erst nach der Extubation zu relevanten Anstiegen von Adrenalin und Noradrenalin (p〈0,05). ADH, ACTH und Cortisol stiegen in beiden Gruppen dagegen bereits nach Intubation und Hautschnitt signifikant (p〈0,05) an. Schlußfolgerung: Das Kreislaufverhalten war in beiden Kollektiven vergleichbar. Hinsichtlich des Aufwachverhaltens konnten keine Gruppenunterschiede festgestellt werden; dies wird auf die kontinuierliche Zufuhr von Midazolam zurückgeführt.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s001010050504
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