The Use and Clinical Observation of the ProSeal Laryngeal Mask Airway in General Anesthesia

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 李成文  薛富善  孙海燕  孙海涛  刘鲲鹏  杨 冬  

中国医学科学院中国协和医科大学整形外科医院麻醉科，北京100041

Chengwen Li, Fushan Xue, Haiyan Sun,  Haitao Sun,  Kunpeng Liu,  Dong Yang

Department of Anesthesiology，Plastic Surgery Hospital，Chinese Academy of Medical Sciences and Peking Union Medical college，Beijing 100041.

                                             　　　　ABSTRACT

Objectives：To observe the application of the ProSeal laryngeal mask airway（PLMA）in patients under general anesthesia and to evaluate maneuverability of PLMA, effect of its insertion on hemodynamics and its availablity during mechanical ventilation.
Methods：40 ASA grade Ⅰ～Ⅱ adult patients undergoing elective plastic surgery were studied. After standard intravenous anesthetic induction，insertion of  PLMA with an introducer was performed. Noninvasive SBP，DBP，HR，and SpO₂ were recorded before and after anesthetic induction，and within 5minutes after PLMA insertion. Characteristics of PLMA and gastric tube insertion，cuff inflation volume，airway seal pressure and the locations of gas leak were were assessed. 
Results：PLMA was inserted successfully in 38 patients (95%), the first-time success rate was 87.5%. The time required to acheive effective airway was 32.6±10.9s. The cuff inflation volume was 26.2±5.7ml. The  airway seal pressures was 27.2±6.1cmH₂O. Hemodynamic changes during PLMA insertion was minimal. Gas leak from the drainage tube of PLMA or gastric insuffation did not occur in all the patients. Gastric tube placement was successful by one attempt in 39 patients（97.5%）.
Conclusion：PLMA insertion is easy with high success rate and had minimal cardiovascular response. PLMA can achieve an effective seal pressure，allows effective mechanical ventilation and provides an easy passage of a gastric tube. Therefore，it is concluded that PLMA is a reliable airway management device for patients under general anesthesia.
key words: ProSeal laryngeal mask airway；General anesthesia； Cardiovascular response；Positive pressure ventilation；Gastric tube

食管引流型喉罩通气道（ProSeal laryngeal mask airway，PLMA）是1种能够将消化道和呼吸道有效分隔开的新型通气道，比标准型喉罩通气道（standard laryngeal mask airway，SLMA）具有更高的安全特性和临床应用特性^[1-3]。在国外，PLMA已成功地用于急救复苏和全身麻醉中呼吸道管理，但在国内目前尚无有关PLMA临床应用的报道。本研究通过观察PLMA插入操作的可行性、对血流动力学的影响、管理要点和在全身麻醉中用于机械通气的有效性，旨在为临床安全有效应用这种新型通气道提供资料。

Asai^[7]发现PLMA可为颈部活动明显受限的患者迅速建立通畅的呼吸道。我们的研究也证实了这一点。由于我们医院的特点，在我们的研究对象中有不少颈部瘢痕挛缩患者或颈部扩张器植入的患者。这些患者均存在有不同程度的颈部屈曲受限和头部后仰受限，可能存在直接喉镜显露声门困难，但我们采用PLMA均有效解决了呼吸道管理问题。在我们的患者中，PLMA插入操作耗时最长的1例也不到1min。在应用中我们也体会到，采用专用引导器进行PLMA插入操作不占用过多的口腔空间，所以PLMA特别适用于具有一定程度张口活动受限的整形外科患者。

　　我们在研究中发现，PLMA插入操作引起的血流动力学反应极其轻微。与麻醉诱导后相比较，虽然PLMA插入操作可引起SBP和DBP的升高，但与麻醉诱导前相比仍明显降低。在麻醉诱导前后和PLMA的插入操作过程中，HR平稳，虽然在PLMA插入操作后HR有所升高，但与麻醉诱导前后和PLMA操作中的HR相比较均不具有显著性。<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

在研究中发现，PLMA通气罩的充气量与呼吸道密封压不具有直线相关性，通气罩充气量和呼吸道密封压与体重指数也缺乏直线相关性。因此可以认为尚缺乏与PLMA呼吸道密封压相关的可靠指标，我们建议在PLMA通气罩的充气操作中必须应用压力测定装置。但也有研究发现，在应用推荐充气量的情况下，通气罩对咽黏膜的压力很少超过34 cmH₂O^[8]。另外需要注意的是，在测定呼吸道密封压的操作中有13例患者出现了心动过缓，这可能与呼吸道压增高所致的肺牵张反射有关。静脉给予阿托品可有效治疗。

Evans等报道，经PLMA的引流管腔插入胃管相当容易，成功率可高达98.6%^[3]。我们的临床应用结果与Evans的结论相一致。在我们的观察中，胃管插入的成功率为97.5%。

总之，经临床应用我们发现，PLMA具有操作简单、成功率高、血流动力学反应小、具有潜在的呼吸道保护作用、可为正压通气提供良好的呼吸道密封压和提供插入胃管的良好通路等优点。对于全身麻醉患者，PLMA是1种安全有效的呼吸道管理工具。

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