Anaesthesia for gynaecological laparoscopy--a comparison between the laryngeal mask airway and tracheal intubation.

In a single-blind, randomised, controlled study, we compared two anaesthetic techniques in 60 patients undergoing gynaecological laparoscopy. In the first group, ventilation was controlled, after paralysis and tracheal intubation. In the second group, a laryngeal mask airway was inserted and spontaneous or assisted ventilation allowed. There were no clinically significant differences in the intra-operative conditions of the two groups, although the procedure was quicker in the second group. The only significant difference in morbidity was a greater incidence of nausea and vomiting in the second group in the first 4 h after operation. We conclude that use of the laryngeal mask airway is an acceptable technique for elective gynaecological laparoscopy, in patients who are at low risk of regurgitation.

Suxamethonium--the relation between dose and response.

In a study which involved 120 adult patients, the ED95 of suxamethonium was shown to be 0.51 mg/kg, using an electromyographic technique. Marked individual variation in response was noted, for example a dose of 0.3 mg/kg produced a range of blockade from 4%-90%. Body surface area was shown to be more significantly related to blockade than lean body mass or total body weight.

Economy in the use of muscle relaxants. Vecuronium after pancuronium.

Vecuronium is an intermediate duration, non-depolarising muscle relaxant. When used during prolonged procedures, it may be given by intermittent injection, by continuous infusion or by a single very large dose at the start of anaesthesia. It may also be used to maintain relaxation after the initial use of a long-acting agent, such as pancuronium. This study demonstrates that the effect of a dose of vecuronium used in this fashion is increased when interaction with pancuronium takes place. The clinical and theoretical implications of this observation are discussed.