Anaesthesia and intensive care
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Anaesth Intensive Care · May 1992
Randomized Controlled Trial Clinical TrialUptake of enflurane and isoflurane during spontaneous and controlled ventilation.
The uptake of enflurane and of isoflurane were studied in forty patients during anaesthesia with nitrous oxide using either spontaneous or controlled ventilation. A Douglas bag method was used in combination with low fresh gas flows to a circle system and constant end-tidal anaesthetic concentration. ⋯ The initial uptake rates were lower than expected from "the square root of time concept". During spontaneous ventilation, the anaesthetic uptake rates were similar or even higher than corresponding rates during controlled ventilation in spite of lower minute ventilation volumes.
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Anaesth Intensive Care · May 1992
Propofol is a 'safe' anaesthetic agent in malignant hyperthermia susceptible patients.
In this study we investigated in vitro and in vivo effects of propofol in malignant hyperthermia susceptible (MHS) patients in order to assess the safety of propofol infusion as a non-triggering anaesthetic technique for diagnostic and therapeutic procedures. In vitro, human MHS muscle samples were exposed to propofol and changes in (a) baseline tension and (b) contracture tension on exposure to halothane and caffeine were measured. In vivo, (a) anaesthesia was induced in ten muscle biopsy positive MHS patients with propofol 2.5 mg/kg and (b) anaesthesia was produced in five muscle biopsy positive MHS patients with infusions of propofol up to 10 mg/kg/hr. ⋯ In vivo, no evidence of an MH response was detected following induction or maintenance of anaesthesia with propofol. Our results and literature review are in agreement that propofol is a 'safe' induction and maintenance agent in MHS patients. Propofol can be used for muscle biopsy anaesthesia because it does not alter the sensitivity of diagnostic muscle biopsy testing.
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Anaesth Intensive Care · May 1992
Randomized Controlled Trial Comparative Study Clinical TrialDouble-blind comparison of patient recovery after induction with propofol or thiopentone for day-case relaxant general anaesthesia.
Postoperative recovery after induction with either propofol or thiopentone has been compared in forty ASA I unpremedicated day surgery patients undergoing surgical extraction of third molar teeth under relaxant general anaesthesia. Mean recovery times in the propofol group, required for patients to sit out of bed (44.8 minutes; SD 18.6) and meet discharge criteria (113.1 minutes; SD 34.5) were significantly (P less than 0.05) shorter than those in the thiopentone group (59.7 minutes; SD 21.4 and 133.5 minutes; SD 34.5). Fewer patients in the propofol group were treated in the recovery room for nausea and vomiting and the incidence of mild nausea not requiring treatment was less in the propofol group, but these differences were not statistically significant. Postoperative mental performance, measured by the FAST index, a new test of mental speed, was reduced on average by 1.7% of preoperative levels, during the recovery period tested, with no significant difference between the groups.
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Anaesth Intensive Care · May 1992
Randomized Controlled Trial Comparative Study Clinical TrialThe addition of pethidine to epidural bupivacaine in labour--effect of changing bupivacaine strength.
The effects of varying the strength of bupivacaine used in epidurals for the relief of labour pain was examined. The trial randomly allocated sixty women in the first stage of labour to one of three groups. All women were of ASA status 1 or 2 and had uncomplicated pregnancies. ⋯ This study suggests that when epidural pethidine 25 mg is added to local anaesthetic solutions of bupivacaine, adequate analgesia for the first stage of labour is achieved with the 0.125% bupivacaine solution. The use of stronger solutions of bupivacaine achieves no greater degree of analgesia nor longer duration of action, although the onset of analgesia may be faster with the stronger solutions. Further investigations are needed to determine if 25 mg of pethidine is the best choice of dose to use under these circumstances.