Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, Diako Hospital, Flensburg, Academic Teaching Hospital of the University of Kiel, Germany.
Anesth Analg. 2010 Apr 1;110(4):1076-82. doi: 10.1213/ANE.0b013e3181d27fb4.
Some severe complications during percutaneous dilatational tracheostomy (PDT) may be related to poor visualization of tracheal structures. Subjectively, the bronchoscopical view obtained via a laryngeal mask airway (LMA) seems to be better than that obtained with an endotracheal tube (ETT). In this prospective, randomized study, we compared LMA and ETT as the ventilatory device during PDT mainly with respect to visualization of tracheal structures. The quality of ventilation and airway-related complications are also reported.
In this prospective, randomized study, PDT was performed using an LMA (n = 33) or an ETT (n = 30). Quality of ventilation and visualization of tracheal structures (thyroid, cricoid, and tracheal cartilages) were rated as follows: very good (1), good (2), difficult (3), and not possible (4) with LMA/ETT. A rating of 4 required the alternate airway. Groups were compared using the chi(2) test.
Visualization of tracheal structures was better with the LMA: ratings were 1 or 2 in 94% of patients with an LMA, compared with 66% of patients with an ETT (P <0.05). Visual control during puncturing the trachea was 1 or 2 in 97% of patients using an LMA and 77% of patients for an ETT (P < 0.05). A rating of 4 was assigned to 1 patient with an LMA and to 3 patients with an ETT. Hemodynamic variables were similar in both groups. Blood gas analysis during PDT showed decreased Pao(2) in both groups, and increased Paco(2), which was more pronounced with an ETT compared with an LMA (59 +/- 14 mm Hg and 51 +/- 11 mm Hg [P < 0.05]). In the ETT group, 2 patients were extubated accidentally, and in another patient, the bronchoscope was damaged because of insufficient visualization of the tracheal puncture site.
The LMA technique showed definite advantages regarding visualization of relevant tracheal structures and the dilation process compared with an ETT. This may be especially relevant in the hands of inexperienced intensivists and in cases of difficult patient anatomy where improved structural visualization optimizes operating conditions.
经皮扩张气管切开术（PDT）过程中发生的一些严重并发症可能与气管结构可视化不良有关。主观上，通过喉罩气道（LMA）获得的支气管镜视图似乎优于通过气管内管（ETT）获得的视图。在这项前瞻性、随机研究中，我们主要比较了 LMA 和 ETT 作为 PDT 期间的通气装置，以比较其对气管结构可视化的影响。同时还报告了通气质量和与气道相关的并发症。
在这项前瞻性、随机研究中，使用 LMA（n=33）或 ETT（n=30）进行 PDT。使用 LMA/ETT 对通气质量和气管结构（甲状腺、环状软骨和气管软骨）的可视化进行如下评分：非常好（1）、好（2）、困难（3）和不可能（4）。评分 4 表示需要更换气道。使用卡方检验比较两组。
LMA 对气管结构的可视化效果更好：LMA 组患者的评分 1 或 2 的比例为 94%，而 ETT 组为 66%（P<0.05）。使用 LMA 时，97%的患者在穿刺气管过程中能够进行视觉控制，而 ETT 组为 77%（P<0.05）。LMA 组有 1 名患者和 ETT 组有 3 名患者评分 4。两组的血流动力学参数相似。PDT 期间的血气分析显示两组的 PaO2 均降低，而 ETT 组的 Paco2 增加更为明显（59±14mmHg 和 51±11mmHg，P<0.05）。ETT 组有 2 名患者意外拔管，另一名患者因气管穿刺部位可视化不足导致支气管镜损坏。
与 ETT 相比，LMA 技术在相关气管结构和扩张过程的可视化方面具有明显优势。在经验不足的重症监护医生手中，或者在解剖结构困难的情况下，改善结构可视化可以优化手术条件，这一点尤其重要。
