SummaryWe compared the performance of the Ambu Ò AuraOnce TM Laryngeal Mask with that of the LMA Classic TM laryngeal mask airway during controlled anaesthesia. Forty patients requiring intermittent positive pressure ventilation were studied using a randomised crossover design. The mean (SD) oropharyngeal leak pressure for the Ambu device (19 (7.5) cmH 2 O) was significantly greater than for the LMA Classic (15 (5.2) cmH 2 O; p ¼ 0.004), and the number of attempts for successful insertions was significantly less (39 (50%) vs 45 (56%), respectively; p ¼ 0.02). There was one failure to obtain a patent airway with the Ambu Laryngeal Mask and none with the LMA Classic. Insertion of the Ambu Laryngeal Mask required more manipulations to achieve a patent airway than did the LMA Classic (6 (15%) vs 1 (2.5%), respectively; p ¼ 0.045), but the time taken for insertion was similar between the two groups. The incidence of trauma, grade of fibreoptic view, peak airway pressure and quality of ventilation during maintenance of anaesthesia were similar in both groups.

BackgroundAmbulatory surgery has recently gain popularity, as it is a good method of optimizinghospital resources utilization. To support ambulatory surgery, anaesthetic goals nowrevolve around patients’ early recovery with minimal pain and nausea, expedientdischarge home and prompt resumption of activities of daily living. In this study, weevaluated the effect of a single pre-induction dose of dexmedetomidine on anaestheticrequirements, postoperative pain and clinical recovery after ambulatory ureteroscopy andureteric stenting under general anaesthesia.MethodsSixty patients were randomised to receive IV dexmedetomidine 0.5 μg.kg-1 (Group DEX, n = 30) or IV saline (Group P, n = 30). General anaesthesia was maintained with Sevoflurane: oxygen: air, titrated to BIS 40–60. Pain intensity, sedation, rescue analgesics, nausea/vomiting and resumption of daily activities were recorded at 1 h, and postoperative day (POD) 1–5.ResultsGroup DEX patients had significant reduction in sevoflurane minimum alveolar concentration (MAC), mean (SD) DEX vs. Placebo 0.6 (0.2) vs. 0.9 (0.1), p = 0.037; reduced postoperative resting pain at 1 h (VAS 0–10) (mean (SD) 1.00 (1.84) vs. 2.63 (2.78), p = 0.004), POD 1 (mean (SD) 1.50 (1.48) vs. 2.87 (2.72), p = 0.002), POD 2 (0.53 (0.97) vs. 1.73 (1.96), p = 0.001) and POD 3 (0.30 (0.75) vs. 0.89 (1.49), p = 0.001). DEX patients also had less pain on movement POD 1 (3.00 (2.12) vs. 4.30 (3.10), p = 0.043) and POD 2 (2.10 (1.98) vs. 3.10 (2.46), p = 0.040), with higher resumption of daily activities by 48 h compared to placebo, 87% vs. 63%, p = 0.04.ConclusionsWe conclude that a single dose of dexmedetomidine was a useful adjuvant in reducing MAC and postoperative pain (at 1 h and POD 1–3), facilitating faster return to daily activities by 48 h.Trial registrationThe Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12617001120369, 31st July 2017, retrospectively registered.

A postal questionnaire survey was sent to Royal College of Anaesthetists' tutors in Great Britain and Northern Ireland to gain insight into current practice with regard to information and consent for anaesthesia. Details of consent practice in three specific areas were requested: anaesthesia in general, teaching medical students during anaesthesia and obstetric anaesthesia. Replies were received from 218 tutors (77%). Of these, 72% of departments had a policy on consent for anaesthesia that was in accordance with The Association of Anaesthetists of Great Britain and Ireland guidelines oǹ Information and Consent for Anaesthesia'. We identified three areas of concern. Firstly, almost a third of departments (27%) had no policy on consent for anaesthesia. Second, only 18% of relevant departments obtain specific consent for the teaching of medical students on anaesthetised patients. Third, 1 year after publication of the guidelines, 17% of obstetric anaesthetic units, despite stating an intention to alter their departmental policy based on the Association's recommendations, had not yet implemented any changes.

SummaryThe 50% and 95% effective doses of desflurane for removal of the classic laryngeal mask airway after suction of the upper airway, in anaesthetised spontaneously breathing adult patients, are not known. To determine these, we studied 38 healthy patients, aged between 18 and 44 years. The target desflurane concentration in each individual patient was determined by the Dixon up-anddown method. When the predetermined target end-tidal desflurane concentration reached steady state, we kept a constant end-expiratory partial pressure between the alveolus and the brain for 10 min before attempting to remove the classic laryngeal mask airway after suctioning the upper airway. The initial desflurane target concentration was set at 6% and up-down desflurane increments were 0.1%. This continued until there were at least six crossover pairs. From the probit analysis, the 50% effective dose of desflurane was 5.29% (95% CI 5.132-5.379%) and the 95% effective dose was 5.55% (95% CI 5.429-6.394%).

Summary Surgical drapes used during eye surgery are impermeable to air and hence risk trapping air underneath them. We investigated the effect of a forced‐air warming blanket on carbon dioxide accumulation under the drapes in patients undergoing eye surgery under local anaesthesia without sedation. Forty patients of ASA physical status 1 and 2 were randomly assigned to either the forced‐air warmer (n = 20) or a control heated overblanket (n = 20). All patients were given 1 l.min−1 oxygen. We measured transcutaneous and end‐tidal carbon dioxide partial pressures, heart rate, arterial pressure, respiratory rate, temperature and oxygen saturation before and after draping, then every 5 min thereafter for 30 min. The mean (SD) transcutaneous carbon dioxide partial pressure in the forced‐air warming group stayed constant after draping at 5.7 (0.2) kPa but rose to a maximum of 6.4 (0.4) kPa in the heated overblanket group (p = 0.0001 for the difference at time points 15 min and later). We conclude that forced‐air warming reduces carbon dioxide accumulation under the drapes in patients undergoing eye surgery under local anaesthesia.