British journal of anaesthesia
-
Systemic mastocytosis is an uncommon disorder of mast cell proliferation in connective tissues. Mast cell degranulation may occur on exposure to various stimuli and drugs. ⋯ Intradermal skin testing is useful in predicting the sensitivity to drugs that may be used during anaesthesia. We present a patient with systemic mastocytosis who underwent uneventful cholecystectomy.
-
We have studied, in the monkey, the critical volume for the production of severe pneumonitis following pulmonary aspiration of gastric contents. Aspiration of 0.4 ml kg-1 and 0.6 ml kg-1 at pH1 produced mild to moderate clinical and radiological changes, but no deaths. ⋯ At 1.0 ml kg-1, 50% of the animals died--a mortality rate considerably less than that reported previously in animal studies. If these results were to be extrapolated to humans, the critical volume for severe aspiration could be increased from 25 ml to 50 ml (0.8 ml kg-1), considerably reducing the percentage of patients perceived to be "at risk".
-
Randomized Controlled Trial Clinical Trial
Measurement of entrainment ratio during high frequency jet ventilation.
We have measured tidal (VT), entrained (Ve) and "blowback" (Vbb) volumes during high frequency jet ventilation (HFJV) through a Mallinckrodt Hi-Lo Jet tracheal tube in anaesthetized patients. The above volumes were calculated by digital integration of the appropriate regions of flow curves derived from a pneumotachograph placed between the bias flow tubing and the tracheal tube. ⋯ Blowback volumes were considerable, especially at ventilatory frequencies used clinically (1-2 Hz). We conclude that it is not possible to entrain predictable concentrations of volatile agents from the low pressure bias flow during HFJV.
-
Clinical Trial Controlled Clinical Trial
Total i.v. anaesthesia with propofol and alfentanil: dose requirements for propofol and the effect of premedication with clonidine.
We determined in 51 healthy patients undergoing body surface surgery the dose requirements for propofol, as part of a total i.v. anaesthesia technique with an alfentanil infusion. After premedication with temazepam, patients received alfentanil 50 micrograms kg-1 followed by an infusion of 50 micrograms kg-1 h-1. Patients were anaesthetized with a loading dose of propofol followed by a three-stage infusion designed to reach one of five preselected blood concentrations of propofol. ⋯ Whole blood concentration!of propofol at the time of the incision was related linearly to the inf!sion rate and the EC50 and EC95 (probit analysis) were derived as !.44 (95% confidence limits 0.62-1.87) and 4.05 (95% confidence lim!ts 2.78-30.5) micrograms ml-1, respectively. Post-operative recovery was!rapid, uncomplicated and uneventful. In a subgroup of eight patients,!the addition of clonidine 0.6 mg to the premedication significantly decreased the requirement for propofol (P less than 0.05) during surgery, but resulted in prolonged recovery times.
-
Randomized Controlled Trial Clinical Trial
IV lignocaine fails to attenuate the cardiovascular response to laryngoscopy and tracheal intubation.
I.v. lignocaine has been used with varying success to attenuate the cardiovascular responses to laryngoscopy and tracheal intubation. We determined the optimal time of administration in 45 ASA I and II Chinese patients premedicated with morphine and hyoscine, and anaesthetized with thiopentone and suxamethonium. Patients were allocated randomly to a control group or three treatment groups to receive lignocaine 1.5 mg kg-1 i.v. 1, 2, or 3 min before laryngoscopy. Analysis of variance for measured and derived cardiovascular variables failed to show any significant difference between any of the groups.