British journal of anaesthesia
-
The effect of the i.v. administration of methylene blue dye on haemoglobin oxygen saturation, measured by a pulse oximeter was investigated. The absorption spectra of various concentrations of haemoglobin, oxyhaemoglobin and methylene blue were compared. The amount of 660-nm light absorbed by methylene blue was sufficient to cause a factitious haemoglobin desaturation as measured by the pulse oximeter.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Controlled comparison of a new sublingual lormetazepam formulation and i.v. diazepam in outpatient minor oral surgery.
In a randomized, double-blind, parallel groups study, 40 patients undergoing surgical removal of impacted 3rd molar teeth received either sublingual lormetazepam 2.5 mg (n = 20) in a new cellulose wafer formulation followed at 35 min by i.v. saline; or sublingual placebo followed at 35 min by i.v. diazepam 10 mg (Diazemuls). Rapid onset of sedation was seen after sublingual lormetazepam, while the course and duration of postoperative sedation, measured using standard psychometric tests, was similar following both treatments. ⋯ Both treatments were tolerated well, with no significant cardiovascular complications. These results indicate that sublingual lormetazepam may have a role in anaesthesia as a premedicant and for conscious sedation.
-
Randomized Controlled Trial Clinical Trial
Modification by alfentanil of the haemodynamic response to tracheal intubation in elderly patients. A dose-response study.
Fifty-five elderly patients undergoing elective ophthalmological surgery were randomly allocated to four groups. Following the induction of anaesthesia with thiopentone (given over 2 min) and the administration of atracurium 0.6 mg kg-1, patients received alfentanil 400, 600, 800 or 1000 micrograms. Intubation of the trachea was performed 90 s later. ⋯ In each of the groups there was a significant decrease in systolic arterial pressure and a significant increase in heart rate on induction of anaesthesia. In those patients who received either 400 or 600 micrograms of alfentanil, arterial pressure increased immediately after tracheal intubation, whereas in those receiving alfentanil 800 or 1000 micrograms, arterial pressure decreased immediately after tracheal intubation, and when measured 10 min after intubation. It is suggested that alfentanil 600 micrograms (10 micrograms kg-1) constitutes the optimal dose with which to obtund the haemodynamic response to tracheal intubation in elderly patients, and to minimize cardiovascular depression after tracheal intubation.
-
Contralateral haemothorax developed as a late complication of subclavian vein cannulation following gradual erosion of the wall of the superior vena cava by the tip of the catheter. The use of a relatively rigid catheter and a left-sided approach may have contributed to this rare, but potentially fatal complication.
-
Comparative Study Clinical Trial Controlled Clinical Trial
Intraocular pressure changes during rapid sequence induction of anaesthesia: comparison of propofol and thiopentone in combination with vecuronium.
Intraocular pressure (IOP) was measured during rapid sequence induction of anaesthesia using thiopentone or propofol as the induction agent and vecuronium for neuromuscular blockade. Vecuronium was administered in a dose of 0.15 mg kg-1 approximately 35 s before the induction agent. IOP was measured with a handheld applanation tonometer before anaesthesia, following administration of the induction agent, immediately after tracheal intubation and cuff inflation and 1, 2 and 3 min later. ⋯ IOP following intubation in patients in whom anaesthesia was induced with thiopentone was not significantly different from baseline values, but showed a significant increase from the pressure before intubation. In contrast, IOP after intubation in the propofol group remained not only significantly less than the baseline value, but also showed only a minimal and insignificant change in comparison with values before intubation. The frequency of side effects was low in both groups except for a significantly greater reduction in arterial pressure in those receiving propofol.