Comparision of Ici 35868, Etomidate and Methohexitone for Day-Case Anaesthesia

Abstract

ICI 35868 is a substituted phenol (2-6, diisopropyl phenol) which has been shown to have anaesthetic properties. It is rapidly acting (7J approximately 55 min), and is completely metabolized, mainly by conjugation with glucuronic acid. There is minimal cumulation, more than 90 % of the dose being recovered in the urine (as metabolites) within 48 h.This study was designed to compare the efficacy and side-effects of di-isopropyl phenol, etomidate and methohexitone, when used for day-case anaesthesia. PATIENTS AND METHODSSeventy-one female patients in good general health (ASA class I), aged between 18 and 65 yr and scheduled for minor gynaecological procedures (dilatation and curettage or termination of pregnancy) were included in this open study. Written informed consent was obtained from each patient. Those with a history of allergy, atopy, previous known exposure to Cremophor and those taking drugs not specified in the trial, were excluded. Patients were allocated randomly to three groups to receive di-isopropyl phenol, etomidate or methohexitone. The number of patients undergoing dilatation and curettage or termination of pregnancy was balanced in each group. Anaesthetic techniqueAll patients received fentanyl 0.001 mg/kg body weight 2 min before the induction of anaesthesia.ICI 35868 was presented as a 1 % solution of di-isopropyl phenol in 16% Cremophor EL with water to 100% (disoprofol), and the other drugs were used in the commercially available preparations (etomidate, Janssen Pharmaceuticals; methohexitone, Eli Lilly & Co. Limited). SUMMARYInduction doses of disoprofol l.Smgkg" 1 (« = 26), etomidate 0.2 mgkg~l(« = 22) or methohexitone 1.5 mg kg~l {n = 23) were administered over 20 s (forearm or antecubital vein), and anaesthesia was maintained with 70% nitrous oxide in oxygen via a face mask, plus further increments of the appropriate induction agent. Incremental doses were 10-20% of the induction dose. At the end of surgery, 100% oxygen was administered for 2 min. Assessments of patientsThe following observations were made by one of two observers (the majority being made by the author): Induction time from the start of injection to the loss of eyelash reflex was measured in seconds; pain on injection was rated as present when reported spontaneously or in response to the question " Is your arm comfortable?" Respiratory abnormalities such as hiccup, sneeze, bronchospasm or apnoea of more than 30 s duration were noted. Heart rate, systolic and diastolic arterial pressures were recorded (Dinamap) at 1-min intervals. Recordings were started 2 min before the induction Downloaded from https://academic.oup.

Comparison of the Induction Characteristics of Thiopentone and Propofol in Children

“…That the incidence and duration of apnoea were almost identical for both drugs reflects on the relatively heavy opioid premedication. It is difficult to compare these findings with adult studies because the reported incidence of apnoea varies from 12 to 100% (Nightingale et al, 1984;Wells, 1985). Fahy, van Mourik and Utting (1985), using a technique similar to that utilized in this study, reported a higher incidence of apnoea with bodi thiopentone and propofol than we have found.…”

“…Using the emulsion formulation, we have found a 24% incidence of pain using antecubital fossa veins, compared with 10% with thiopentone. Although none were considered to be severe, these findings contrast markedly with die low incidence of pain diat was found in adults using antecubital fossa veins and the emulsion formulation of propofol (2.5-12%), or thiopentone (0%) (Kawar and Dundee, 1982;McCulloch and Lees, 1985;Wells, 1985). The incidence of pain on injection in adults is higher when the smaller veins on the dorsum of the hand are used (Kawar and Dundee, 1982;McCulloch and Lees, 1985;Mackenzie and Grant, 1985).…”

Propofol vs thiopentone as anaesthetic agents for short operative procedures

“…With the new emulsion formulation the incidence of pain on injection is lower but still occurs in 30-50:/, of patients when injected into veins in the dorsum of the hand (10, 11). If, however, veins in the forearm or in the antecubital Sossa are used, the incidence of pain can be substantially reduced (to about 10%) (12).…”

Excitatory phenomena following the use of propofol in dogs

“…Clinical trials of propofol used in conjunction with other induction agents, suggested that, in man, fewer and less significant side effects were seen than with methohexitone or etomidate. It compared favourably with thiopentone (Wells 1985;McCollum and Dundee 1986). A multicentre study of the drug (Sanderson 1988), performed after its launch in the open market, found that about 8.4 per cent of patients had abnormal reactions following its administration.…”