Brimacombe J, Keller C, Morris R, Mecklem D
Department of Anaesthesia and Intensive Care, Cairns Base Hospital, Australia. 100236,
Anesth Analg. 1998 Oct;87(4):921-4. doi: 10.1097/00000539-199810000-00033.
A disposable (polyvinyl chloride) laryngeal mask airway (LMA) with dimensions identical to, but physical properties different from (stiffer tube/thicker cuff), the reusable (silicone) LMA has recently become available. We performed a randomized, cross-over study of 60 paralyzed, anesthetized patients to test the hypothesis that the use of these devices was different in terms of ease of insertion, airway sealing pressure, fiberoptic position, and changes in intracuff pressure during N2O anesthesia. We also tested the hypothesis that the airway sealing pressure of the LMA is suboptimal if the cuff is inflated to a high intracuff pressure. Both the devices were inserted into each patient in random order, and their performance was assessed at two intracuff pressures (60 and 180 cm H2O) by a blind observer. Subsequently, intracuff pressures were measured during N2O anesthesia for the second device. Ease of insertion was similar: there was no difference in first attempt success rates (97% vs 98%) and insertion times (15 vs 13 s) for the disposable and reusable LMA, respectively. There were no differences in airway sealing pressure or fiberoptic position. Airway sealing pressure was significantly higher at 60 cm H2O intracuff pressure compared with the airway sealing pressure at 180 cm H2O for both devices (P < 0.02). During N2O anesthesia, the intracuff pressure remained stable for the disposable LMA but increased significantly for the reusable LMA. We conclude that the disposable and reusable LMAs perform similarly in paralyzed adult patients, but that the disposable LMA has more stable intracuff pressures during N2O anesthesia. Inflation of the LMA to high intracuff pressures produces a suboptimal seal.
This randomized, single-blind, within-patient study of 60 adult patients shows that the disposable (polyvinyl chloride) and reusable (silicone) laryngeal mask airways perform similarly, but that the disposable laryngeal mask airway has more stable intracuff pressures during N2O anesthesia. Inflation of either device to high intracuff pressures produces a suboptimal seal.
一种一次性（聚氯乙烯）喉罩气道（LMA），其尺寸与可重复使用的（硅胶）LMA相同，但物理特性不同（管更硬/套囊更厚），最近已上市。我们对60例瘫痪、麻醉的患者进行了一项随机交叉研究，以检验以下假设：在插入的难易程度、气道密封压力、纤维光学位置以及氧化亚氮麻醉期间套囊内压力变化方面，使用这些装置存在差异。我们还检验了以下假设：如果将喉罩气道的套囊充气至较高的套囊内压力，则其气道密封压力将不理想。两种装置以随机顺序插入每位患者，并由一位盲法观察者在两个套囊内压力（60和180 cm H2O）下评估其性能。随后，在氧化亚氮麻醉期间测量第二个装置的套囊内压力。插入的难易程度相似：一次性和可重复使用的喉罩气道首次尝试成功率（分别为97%对98%）和插入时间（分别为15秒对13秒）没有差异。气道密封压力或纤维光学位置没有差异。两种装置在套囊内压力为60 cm H2O时的气道密封压力均显著高于套囊内压力为180 cm H2O时的气道密封压力（P < 0.02）。在氧化亚氮麻醉期间，一次性喉罩气道的套囊内压力保持稳定，而可重复使用的喉罩气道的套囊内压力显著升高。我们得出结论，一次性和可重复使用的喉罩气道在瘫痪成年患者中的表现相似，但一次性喉罩气道在氧化亚氮麻醉期间的套囊内压力更稳定。将喉罩气道充气至较高的套囊内压力会产生不理想的密封。
这项对60例成年患者进行的随机、单盲、患者内研究表明，一次性（聚氯乙烯）和可重复使用的（硅胶）喉罩气道表现相似，但一次性喉罩气道在氧化亚氮麻醉期间的套囊内压力更稳定。将任何一种装置充气至较高的套囊内压力都会产生不理想的密封。
