British journal of anaesthesia
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Randomized Controlled Trial Clinical Trial
Rate of injection through whitacre needles affects distribution of spinal anaesthesia.
A prospective, randomized, double-blind study was performed to investigate whether altering the rate of injection of local anaesthetic through a Whitacre needle had any effect on the spinal block achieved. Twenty patients scheduled for elective urological surgery under spinal anaesthesia received an injection of 3 ml of 0.5% plain bupivacaine either by hand (fast) over 10 s (18 ml min(-1)) or by infusion pump (slow) over 3 min (1 ml min(-1)). All patients were in the sitting position both during insertion of the spinal needle and for 3 min after the start of spinal injection, and they then changed to the supine position. ⋯ The time to lowest mean arterial pressure occurred earlier in the slow group, at 10 (8 to 18) vs 20 (15-31) min (P<0.05). Duration of the motor block was shorter in the slow group: 180 (152-242) vs 270 (225-300). We conclude that a slow spinal injection of plain bupivacaine results in a block of more rapid onset and recovery.
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Randomized Controlled Trial Comparative Study Clinical Trial
Attenuation of haemodynamic responses to tracheal intubation by the styletscope.
Tracheal intubation often causes a haemodynamic response probably generated by direct laryngoscopy. The StyletScope is a new intubation device that does not require direct laryngoscopy. We prospectively measured haemodynamic changes after tracheal intubation using the StyletScope. The increase of heart rate was less during tracheal intubation with the StyletScope when compared with the Macintosh laryngoscope.
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Randomized Controlled Trial Comparative Study Clinical Trial
Sevoflurane EC50 and EC95 values for laryngeal mask insertion and tracheal intubation in children.
The laryngeal mask airway (LMA) is a simple, easy to use and safe method for airway control in children. Its insertion needs less anaesthetic, and haemodynamic responses and postoperative sequelae are less than with laryngoscopy and tracheal intubation. This study was designed to determine the end-tidal concentrations of sevoflurane where 50% (EC50) and 95% (EC95) of the attempts to secure the airway would be successful. ⋯ Sevoflurane provided good conditions for both LMA insertion, and laryngoscopy and tracheal intubation without serious adverse effects. The EC50 and the EC95 of sevoflurane were 1.57 (SD 0.33)% and 2.22% for LMA insertion and 2.20 (SD 0.31)% and 2.62% for laryngoscopy and tracheal intubation. Thus, less sevoflurane is required for LMA insertion in children than for laryngoscopy and tracheal intubation.
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Randomized Controlled Trial Clinical Trial
Absence of memory for intra-operative information during surgery with total intravenous anaesthesia.
While using the isolated forearm technique, we wished to determine whether patients who did not respond to commands during general anaesthesia with a total intravenous technique (propofol and alfentanil with atracurium) had any evidence of post-operative explicit or implicit memory. Forty women undergoing major gynaecological surgery were randomized, in a double-blind design, to hear two different tapes during surgery. ⋯ We conclude that during total intravenous anaesthesia with propofol and alfentanil, there is no evidence that learning takes place when anaesthesia is adequate. Furthermore, with this anaesthetic technique, it would seem that--provided any period of patient responsiveness is short and that unconsciousness is induced rapidly again--there is no evidence of implicit or explicit memory.
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Randomized Controlled Trial Clinical Trial
Haemodynamic and renal effects of intravenous enalaprilat during coronary artery bypass graft surgery in patients with ischaemic heart dysfunction.
Renal dysfunction occurring after open heart surgery is multifactorial in origin but activation of the renin-angiotensin system may have a prominent role. Fourteen patients with ischaemic heart dysfunction scheduled for elective coronary artery bypass graft (CABG) surgery were allocated to a treatment group [enalaprilat for 2 days; ACEI (angiotensin-converting enzyme inhibitor) group, n=7] or a control group (n=7). The cardiac index was significantly higher in ACEI-treated patients than in the controls before and after cardiopulmonary bypass (CPB) (P<0.05) and on postoperative day 2 (P<0.05). ⋯ The study demonstrates that administration of an i.v. ACEI, enalaprilat, improves cardiac output during CABG surgery in patients with ischaemic heart dysfunction. Moreover, renal perfusion was better maintained during surgery, and this effect was sustained up to post-operative day 7.