A simplified, safe and flexible technique of anesthesia, based on a limited number of relatively cheap drugs, and allowing ventilation with air, was applied to 60 patients undergoing operations of at least 60 minutes' duration. The required depth of hypnosis was produced by intravenous diazepam or gamma-OH, whilst droperidol and fentanyl provided a satisfactory degree of sedation and analgesia. Pancuronium bromide was used for muscle relaxation. Spontaneous respiration was resumed immediately after postoperative use of nalorphine and neostigmine.
South African Medical Journal = Suid-Afrikaanse Tydskrif Vir Geneeskunde
Etomidate (Hypnomidate; Ethnor) in an alcoholic solution was used as the hypnotic component of a technique of total intravenous anaesthesia in an open pilot evaluation in 50 patients undergoing surgery. No anaesthetic gases were used. Despite cardiovascular stability, lack of respiratory depression and a short awakening time, unwanted movements by the patients made total intravenous anaesthesia with this technique unsatisfactory.
An etomidate infusion regimen for hypnosis as part of balanced, totally intravenous anesthesia was designed to maintain plasma etomidate concentrations above the awakening concentration of 300 ng/ml while avoiding dose-related side effects. The etomidate infusion regimen of 0.1 mg/kg/min for 3 min, 0.02 mg/kg/min for 27 min, and 0.01 mg/kg/min for the remainder of the anesthesia was used together with intravenous bolus doses of fentanyl, droperidol, and pancuronium. This was evaluated in 11 patients and the kinetics of etomidate were reexamined.
Sufentanil citrate is a potent analogue of fentanyl that has been evaluated primarily for use in opioid anesthesia. It is a pure mu receptor agonist and produces the typical spectrum of opioid effects. The major side effects are truncal rigidity and prolonged respiratory depression. In doses of 4-30 micrograms/kg sufentanil produces hypnosis and suppresses most hemodynamic and hormonal responses to surgery without producing significant cardiovascular depression. In this respect sufentanil and fentanyl have clear advantages over morphine, meperidine and potent inhalation anesthetics.
The effects of a single dose of cyclosporine on anesthetic actions of pentobarbital and fentanyl were studied in mice. Mice given pentobarbital 2 hr after receiving cyclosporine, 60 mg/kg, slept a statistically significant 2.3 times longer than did controls. In a second study, each of two dose levels of cyclosporine was given before each of four dose levels of fentanyl. The analgesic effect of fentanyl, measured with the abdominal constriction test, was dose-dependent. Cyclosporine significantly increased the analgesia produced by fentanyl and did so in a dose-dependent manner.
Midazolam and alfentanil were infused in a totally i.v. anesthetic technique (TIVA) to patients undergoing hysterectomy. Correlations of midazolam plasma concentrations and effects were made during recovery. Due to the high doses of midazolam administered during TIVA, metabolism and not redistribution mainly governed the duration of effects post-infusion. The concomitant administration of alfentanil contributed to the sedative effect, as illustrated by a shift of the concentration-response curve to the left. As a result of these effects, recovery was prolonged and extended over 2-6 h.
The combination of propofol and alfentanil was administered to 20 patients for total intravenous anaesthesia during general surgery. The infusion rates for both drugs were controlled by microprocessors in order to institute constant blood levels adapted to the patients' varying needs. The mean blood level of propofol required for adequate hypnosis during anaesthesia was 2.42 micrograms/ml (SD 0.43). Awakening occurred 7.9 minutes (SD 3.4) after the end of the infusion, at a propofol blood level of 1.59 micrograms/ml (SD 0.34).
Journal of Veterinary Pharmacology and Therapeutics
The pharmacokinetics and clinical effects of the short-acting hypnotic R 8110 and of the narcotic analgesic fentanyl were studied in the dog. The effects of separate intravenous (i.v.) injections of R 8110 (4 mg/kg) and fentanyl (0.015 mg/kg) and of concurrent i.v. injection of the two were studied. After administration of R 8110, induction of hypnosis occurred within 1 min, maximal depth of anaesthesia and satisfactory analgesia and muscle relaxation were obtained after 5 min. The effects had decreased within 15 min and full recovery occurred within 30 min.
Fifty-two female patients who underwent gynaecological operations as day cases received either a short pre-operative hypnotic induction or a brief discussion of equal duration. Hypnotized patients who underwent vaginal termination of pregnancy required significantly less methohexitone for induction of anaesthesia. They were also significantly more relaxed as judged by their visual analogue scores for anxiety. Less than half of the patients were satisfied with their knowledge about the operative procedure even after discussions with the surgeon and anaesthetist.