British journal of anaesthesia
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of four methods for assessing airway sealing pressure with the laryngeal mask airway in adult patients.
We have compared four tests for assessing airway sealing pressure with the laryngeal mask airway (LMA) to test the hypothesis that airway sealing pressure and inter-observer reliability differ between tests. We studied 80 paralysed, anaesthetized adult patients. Four different airway sealing pressure tests were performed in random order on each patient by two observers blinded to each other's measurements: test 1 involved detection of an audible noise; test 2 was detection of end-tidal carbon dioxide in the oral cavity; test 3 was observation of the aneroid manometer dial as the pressure increased to note the airway pressure at which the dial reached stability; and test 4 was detection of an audible noise by neck auscultation. ⋯ Inter-observer reliability of all tests was classed as excellent. The manometric stability test had a higher mean airway sealing pressure (P < 0.0001) and better inter-observer reliability (P < 0.0001) compared with the three other tests. We conclude that for clinical purposes all four tests are excellent, but that the manometric stability test may be more appropriate for researchers comparing airway sealing pressures.
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Comparative Study
Liability of laryngeal mask airway devices to thermal damage from KTP and Nd:YAG lasers.
We have compared the liability of four laryngeal mask airway (LMA) devices (standard, flexible, intubating and reusable) and a tracheal tube to thermal damage from KTP and Nd:YAG lasers at two power densities used commonly in airway surgery: 570 W cm-2 and 1140 W cm-2. Eighty-five airway devices were tested: 24 standard LMA (silicone-based), 12 flexible LMA (silicone-based, metal wires), 24 disposable LMA (PVC-based), one intubating LMA (silicone and steel-based) and 24 PVC-based tracheal tubes. Comparisons were made during laser strike to eight different targets: the unmarked and marked part of the airway device tube; the unmarked part of the airway device tube after application of blood; the cuff filled with air or methylene blue dye; the unmarked flexible LMA tube on or between the metal wires; and the epiglottic elevator bar of the intubating LMA. ⋯ Print markings, blood and the metal wires of the flexible LMA reduced the thermal resistance of the tube. Filling the cuff with methylene blue dye increased the thermal resistance of all airway devices. We conclude that the silicone-based LMA devices were more thermal resistant to KTP and Nd:YAG laser strike than PVC-based devices with the exception of the disposable LMA cuff and the intubating LMA tube.
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Randomized Controlled Trial Multicenter Study Clinical Trial
Antiemetic activity of the NK1 receptor antagonist GR205171 in the treatment of established postoperative nausea and vomiting after major gynaecological surgery.
In this double-blind, randomized, parallel group study, we have investigated the antiemetic activity of the potent and selective NK1 receptor antagonist GR205171 25 mg i.v. compared with placebo in the treatment of established postoperative nausea and vomiting (PONV) in patients after major gynaecological surgery performed under general anaesthesia. The incidence of PONV in the study population was 65%. ⋯ The stimuli for emesis after PONV are multifactorial and the efficacy of GR205171 in this study supports the broad spectrum potential for NK1 receptor antagonists in the management of postoperative emesis. GR205171 was well tolerated and no adverse events were reported that would preclude the further development of this agent.
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Randomized Controlled Trial Comparative Study Clinical Trial
I.v. diclofenac and ketorolac for pain after thoracoscopic surgery.
We studied intensity of pain, cumulative morphine consumption, ventilatory and renal function, and haemostasis in patients undergoing video-assisted thoracoscopic surgery and receiving a 2-day i.v. infusion of diclofenac, ketorolac or saline. Plasma concentrations of the two NSAID were also measured. The study was randomized, double-blind and placebo-controlled, with 10 patients in each group. ⋯ Diclofenac and ketorolac were equally effective in reducing total morphine consumption (61% and 52%, respectively). Adverse events were similar and minor. Greater variability in plasma concentrations of ketorolac were detected compared with diclofenac.