Langenstein H
Klinik für Anaesthesie und operative Intensivtherapie, Ruhr-Universität Bochum, Knappschaftskrankenhaus.
Anaesthesist. 1995 Oct;44(10):712-8. doi: 10.1007/s001010050207.
The laryngeal mask airway (LMA) was prospectively used in patients who were difficult to intubate to evaluate whether it improves ventilation compared to a face mask, facilitates fibreoptic intubation, and how often blind intubation would be possible.
In a university hospital, 30 patients who were difficult to intubate (35 operative procedures) and 50 normal subjects were investigated; 23 patients had had radical resection of a facial tumor with irradiation at a previous time and 7 could not be intubated conventionally (grade 3 and 4 visibility of the larynx according to Cormack [14]). Blind intubation was attempted with a bent bougie, a 6.0-mm uncuffed tube, or a straight bougie.
Insertion of the LMA was possible in all except 1 patient with a mouth opening of 1 cm. Ventilation via the LMA was always excellent and, for tumor patients, superior to a face mask. In tumor patients, leak pressure was higher than in patients with normal cervical anatomy either with or without difficult intubation conditions (25.2 +/- 7.9, P < 0.05, vs. 20.8 +/- 4.4 vs. 20.6 +/- 4.9 cmH2O; n.s.; Fig. 2). Fibreoptic intubation through the LMA was successful in all cases and easier than via a nasal or oral route. Blind intubation was successful in 22% of difficult to intubate patients and 19% of normals, mainly using a 6.0 mm uncuffed endotracheal tube. Substitution of an uncuffed oral tube inserted via the LMA by a nasal endotrachel tube using a reinforced stomach tube is described (Fig. 4).
The LMA improves ventilation, facilitates fibreoptic intubation, and offers the possibility for blind endotracheal intubation in difficult to intubate patients. Blind intubation though the LMA has to be practised extensively to have a high success rate. The LMA represents an additional aid for the anaesthetic management of patients who are difficult to intubate.
前瞻性地将喉罩气道（LMA）应用于插管困难的患者，以评估与面罩相比其是否能改善通气、是否便于纤维光导喉镜引导插管以及盲探插管的成功率。
在一所大学医院，对30例插管困难患者（35例手术操作）和50例正常受试者进行了研究；23例患者曾接受过面部肿瘤根治性切除并放疗，7例患者常规插管困难（根据Cormack分级法[14]，喉部可视度为3级和4级）。尝试使用弯探条、6.0毫米无套囊导管或直探条进行盲探插管。
除1例开口仅1厘米的患者外，所有患者均成功插入LMA。通过LMA进行的通气始终良好，对于肿瘤患者，优于面罩通气。在肿瘤患者中，无论有无插管困难情况，LMA的漏气压力均高于颈部解剖结构正常的患者（分别为25.2±7.9、20.8±4.4和20.6±4.9厘米水柱；P<0.05；无显著差异；图2）。通过LMA进行纤维光导喉镜引导插管在所有病例中均获成功，且比经鼻或经口途径更容易。在插管困难患者中，22%的盲探插管成功，在正常受试者中成功率为19%，主要使用6.0毫米无套囊气管导管。文中描述了使用加强型胃管经LMA插入无套囊口腔导管后再替换为鼻气管导管的方法（图4）。
LMA可改善通气、便于纤维光导喉镜引导插管，并为插管困难的患者提供盲探气管插管的可能性。通过LMA进行盲探插管必须广泛练习以提高成功率。LMA是插管困难患者麻醉管理的一种辅助手段。
