British journal of anaesthesia
-
Randomized Controlled Trial Clinical Trial
Appropriate size and inflation of the laryngeal mask airway.
We have compared size 3 and size 4 laryngeal masks in 30 females and size 4 and size 5 in 30 males for success rate of insertion, incidence of airleak and pressure exerted on the pharynx. First, the ex vivo volume-pressure relationship of the mask was obtained. Second, after insertion of a mask, the cuff was inflated with the recommended maximum volume of air and intracuff pressure measured. ⋯ In females, airleak occurred in 15 patients with the size 3 and in five patients with the size 4 (difference: P = 0.005) and in males, 21 patients with the size 4 and in four patients with the size 5 (P < 0.001). Removal of air to the minimum effective volume significantly decreased intracuff pressure and pressure on the pharynx; on removal of the mask, pressures were similar to, or lower than, initial pressures. Therefore, a larger mask (size 4 in females and size 5 in males) provided a better seal than a smaller size without producing higher pressures on the pharynx.
-
Randomized Controlled Trial Clinical Trial
Caudal anaesthesia with 0.375% ropivacaine or 0.375% bupivacaine in paediatric patients.
We have determined the effectiveness and degree of motor block produced by the new local anaesthetic, ropivacaine, when used for caudal anaesthesia in children. We studied 60 children, aged 3-6 yr, ASA I, allocated randomly in a double-blind manner, to receive one of two local anaesthetics: 0.375% ropivacaine 1.0 ml kg-1 or 0.375% bupivacaine 1.0 ml kg-1. Patients were anaesthetized with continuous infusion of propofol 200 micrograms kg-1 min-1. ⋯ The ropivacaine group showed a shorter duration of motor block than the bupivacaine group (P < 0.05). Postoperative analgesia was required at a mean time of 5 (SD 3.2) h in the ropivacaine group compared with 5 (2.8) h in the bupivacaine group. These findings suggest that caudal anaesthesia with ropivacaine in paediatric patients is effective and produces less motor block in the postoperative period.
-
Randomized Controlled Trial Clinical Trial
Thiopental or etomidate for rapid sequence induction with rocuronium.
We have assessed the effect of the choice of i.v. induction agent on intubation conditions, 60 s after administration of rocuronium 0.6 mg kg-1. We studied 60 adult patients, allocated randomly to one of two groups. Anaesthesia was induced with alfentanil 10 micrograms kg-1 followed by thiopental 5 mg kg-1 (AT-R group; n = 30) or etomidate 0.3 mg kg-1 (AE-R group; n = 30). ⋯ The difference between the two groups was not significant. Of the three components of the intubation score assessed, response to intubation stimulus was significantly less pronounced in group AE-R compared with group AT-R (P < 0.05): group AE-R, no reaction in 24 patients, slight diaphragmatic movement in five and mild coughing in one patient; group AT-R, no reaction in 13, slight diaphragmatic movement in 14, mild coughing in two and severe coughing in one patient. We conclude that etomidate as part of an induction regimen containing alfentanil and rocuronium attenuated the reaction to intubation to a greater extent than thiopental.
-
Randomized Controlled Trial Clinical Trial
Effect of remifentanil on the haemodynamic response to orotracheal intubation.
We have examined the effect of remifentanil on the haemodynamic response to orotracheal intubation in a randomized, double-blind study. We studied 40 patients allocated to one of four groups of 10 each, to receive the following immediately before induction of anaesthesia: remifentanil 1 microgram kg-1 bolus over 30 s, followed by an infusion of 0.5 microgram kg-1 min-1; saline placebo only; glycopyrrolate 200 micrograms and remifentanil 1 microgram kg-1 bolus over 30 s, followed by an infusion of 0.5 microgram kg-1 min-1; or glycopyrrolate 200 micrograms only. Anaesthesia was induced with propofol, vecuronium and 1% isoflurane with 66% nitrous oxide in oxygen. ⋯ Arterial pressure and heart rate were measured non-invasively, immediately before induction of anaesthesia and then at 1-min intervals. Remifentanil was found to effectively attenuate the pressor response to intubation (P < 0.05 for the increase in mean arterial pressure; P < 0.01 for the increase in heart rate). In the absence of a concurrent vagolytic agent, remifentanil was associated with bradycardia or hypotension, or both, in five of 10 patients, compared with one patient who received remifentanil and glycopyrrolate.