Department of Anesthesia, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada.
Anesthesiology. 2010 Mar;112(3):652-7. doi: 10.1097/ALN.0b013e3181cf4346.
Adverse events such as pharyngolaryngeal complications are indicators of quality patient care. Use of manometry to limit the laryngeal mask airway (LMA) intracuff pressure is not currently a routine practice. This double-blind randomized trial compared pharyngolaryngeal complications in patients managed with manometers to limit the LMA intracuff pressure (<44 mmHg) with patients under routine care.
Two hundred consenting patients who underwent ambulatory surgery were randomly allocated to pressure-limiting and routine care groups. Anesthesia was induced with propofol and fentanyl, and maintained with desflurane in air-oxygen. An LMA was inserted, and the cuff was inflated as per usual practice. The patients breathed spontaneously. Research assistants measured the LMA intracuff pressure. In the pressure-limiting group, LMA intracuff pressure was adjusted to less than 44 mmHg. No intervention was performed in the routine care group. Sore throat, dysphonia, and dysphagia were assessed at 1, 2, and 24 h postoperatively. Composite pharyngolaryngeal complications were compared using chi-square test.
Baseline demographic data were comparable between groups. Mean LMA intracuff pressure was less in the pressure-limiting group versus the routine care group (40 +/- 6 vs. 114 +/- 57 mmHg, P < 0.001). The incidence of composite pharyngolaryngeal complications was significantly lower in the pressure-limiting group versus the routine care group (13.4 vs. 45.6%, P < 0.001), with a relative risk reduction of 70.6%, and a number needed to treat of three (95% CI 2.2-7.5).
Reduction of LMA intracuff pressure to less than 44 mmHg lowers the incidence of postoperative pharyngolaryngeal complications. The LMA cuff pressures should be measured routinely using manometry, and deflating the intracuff pressure to less than 44 mmHg should be recommended as anesthetic best practice.
咽喉并发症等不良事件是衡量患者护理质量的指标。目前，使用测压计限制喉罩气道（LMA）内套囊压力并不是常规做法。本双盲随机试验比较了使用测压计限制 LMA 内套囊压力（<44mmHg）与常规护理的患者的咽喉并发症。
200 名同意接受门诊手术的患者被随机分配到压力限制组和常规护理组。麻醉诱导用丙泊酚和芬太尼，空气-氧气中用地氟醚维持。插入 LMA 并按常规方法充气。患者自主呼吸。研究助理测量 LMA 内套囊压力。在压力限制组，将 LMA 内套囊压力调整至<44mmHg。常规护理组不进行干预。术后 1、2 和 24 小时评估咽痛、声音嘶哑和吞咽困难。使用卡方检验比较复合咽喉并发症。
两组的基线人口统计学数据相似。压力限制组的平均 LMA 内套囊压力明显低于常规护理组（40±6 对 114±57mmHg，P<0.001）。压力限制组的复合咽喉并发症发生率明显低于常规护理组（13.4 对 45.6%，P<0.001），相对风险降低 70.6%，治疗人数为 3（95%CI 2.2-7.5）。
将 LMA 内套囊压力降至<44mmHg 可降低术后咽喉并发症的发生率。应常规使用测压计测量 LMA 套囊压力，并推荐将内套囊压力降至<44mmHg 作为麻醉最佳实践。
