Canadian journal of anaesthesia = Journal canadien d'anesthésie
-
Edrophonium administered in divided doses has been reported to accelerate antagonism of neuromuscular blockade, i.e., a "priming" effect. Since measured onset times can be affected by the type of stimulation used, this effect was studied using both train-of-four (TOF) and single twitch (ST) stimulation. During thiopentone-nitrous oxide-enflurane anaesthesia 20 adults were given atracurium 0.5 mg.kg-1. ⋯ Giving edrophonium in divided doses did not improve recovery significantly, measured with either T1, ST or train-of-four ratio (T4/T1). Five minutes after the first administration of edrophonium, T1 was (mean +/- SEM) 86 +/- 3 and 86 +/- 2 per cent control in the single and divided dose groups respectively. Corresponding values for ST were 89 +/- 1 and 89 +/- 2 per cent (NS), and for TOF, 49 +/- 3 and 57 +/- 3 per cent (NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
-
A case of intraoperative awareness during a thoracotomy is described. The patient's recall coincided with an intraoperative period during which a Siemens 900B ventilator and a Siemens 952 isoflurane vaporiser were used. ⋯ This problem eventually was traced to a malfunctioning inlet control valve on the ventilator. This complication may have been prevented if the end-tidal anaesthetic concentration had been monitored intraoperatively.
-
In order to determine correlations between electromyographic (EMG), mecanomyographic (MMG) and clinical criteria of adequate recovery from neuromuscular blockade with vecuronium, seven young healthy conscious volunteers were given subparalysing doses of vecuronium. During recovery from neuromuscular blockade, vital capacity, negative inspiratory pressure, peak expiratory flow rate and five-second head lift were assessed. ⋯ We found that all subjects maintained head lift for five seconds at EMG T4T1 of 0.70, and they achieved normal respiratory tests at EMG T4/T1 of 0.90. The MMG T4/T1 needed for the subjects to perform normal respiratory tests was found to be 0.50, at which time six of the seven subjects were able to perform adequately the head lift test.
-
Randomized Controlled Trial Clinical Trial
Bolus doses of esmolol for the prevention of perioperative hypertension and tachycardia.
The effectiveness of esmolol, an ultra short-acting cardioselective beta blocker, in the prevention and treatment of post-intubation haemodynamic perturbations, was investigated. Forty-eight ASA physical status I and II patients undergoing hysterectomy were randomly assigned to receive a single intravenous bolus of placebo, esmolol 100 mg, or esmolol 200 mg in a double-blind fashion. This was administered over 15 sec, and immediately followed by thiopentone 3-5 mg.kg-1, succinylcholine 1.5 mg.kg-1, and tracheal intubation 90 sec later. ⋯ The systolic blood pressure post-induction was lower in the esmolol 200 mg group (P less than 0.05); following intubation, however, no significant differences were seen among groups in systolic, diastolic, or mean blood pressures. Following tracheal intubation, the incidence of ventricular arrhythmias was lower in the esmolol groups (P less than 0.05). In summary, esmolol in 100 mg and 200 mg doses was effective in mitigating the haemodynamic response following tracheal intubation.
-
Comparative Study
Pharmacokinetics and cardiovascular dynamics of pipecuronium bromide during coronary artery surgery.
The haemodynamic effects of 200 micrograms.kg-1 pipecuronium and pancuronium were compared under etomidate/piritramide anaesthesia in 20 patients scheduled for elective coronary artery surgery. Following the completion of the haemodynamic measurements (ten minutes), anaesthesia was maintained by etomidate/sufentanil infusion. The mean changes in cardiac output were approximately -19 and -2 per cent and in heart rate -1 and +26 per cent for pipecuronium and pancuronium respectively. ⋯ Approximately 56 per cent of the dose was recovered from the urine within 24 hours of administration and about 25 per cent of this was the metabolite, 3-desacetyl pipecuronium. High-dose pipecuronium administration under the anaesthetic regimen employed did not produce deleterious haemodynamic effects. The pharmacokinetic variables after bolus injection of pipecuronium did not deviate from those reported under normothermic conditions.