超声测量颈前软组织厚度用于困难喉镜暴露预测分析

Prediction of difficult laryngoscopy using ultrasound measurement of anterior neck structure

目的:探讨气管前软组织厚度是否能用于困难气道的预测,找到适合中国人群的测量层面及软组织厚度临界值,并与传统气道评估方法比较预测困难气道的准确性。方法:141例择期手术患者,年龄13～88岁,ASA分级Ⅰ～Ⅲ级,术前测量颈围,上、下切牙间距,甲颏间距,Mallampati分级,使用超声仪器测量患者5个层面的颈前软组织厚度,包括舌骨平面、甲状舌骨膜平面、声带平面、甲状腺峡部平面及胸骨上凹平面。诱导后气管插管时记录CormackLehane分级,将Cormack-LehaneⅢ～Ⅳ级定为喉镜暴露困难。分析困难喉镜暴露组与非困难喉镜暴露组间各种评估方法的差异,计算超声测量指标的受试者工作特征曲线(ROC)下面积及临界值,比较各种方法对预测喉镜暴露困难的准确率。采用SPSS19.0软件包进行数据分析。结果:141例患者中,17例出现困难喉镜暴露(Cormack-Lehane分级Ⅲ～Ⅳ级)。困难喉镜暴露组患者甲状舌骨膜平面及声带平面的颈前软组织厚度分别为(2.43±0.50)cm和(0.98±0.21) cm,非困难喉镜暴露组分别为(2.08±0.39)cm和(0.87±0.20)cm,均有显著差异(P<0.05);而甲状舌骨膜平面厚度与声带平面厚度之差结果也有显著差异[(1.46±0.40)cm∶(1.22±0.37)cm],甲状舌骨膜平面、声带平面及两者平面之差的临界值分别为2.19、1.05和1.19 cm。结论:超声测量的甲状舌骨膜平面颈前组织厚度、声带平面颈前组织厚度以及两者之差均可用于预测困难喉镜暴露。

PURPOSE: To verify the accuracy of ultrasonic measurement of the anterior neck soft tissue to predict difficult airway, to find a suitable value of the anterior neck soft tissue for Chinese population, and to compare the accuracy with other airway assessments. METHODS: One hundred and forty-one patients were included, aged 13 to 88 years old, ASA class Ⅰ-Ⅲ, undergoing endotracheal intubation for an elective surgical procedure. The name, gender, age, height, weight of each patient were recorded. The clinical screening tests to predict difficult airway were performed(BMI,interincisoral gap, modified Mallampati score, thyromental distance). Ultrasound(US) measurements of anterior neck soft tissue were obtained(the level of hyoid bone, thyrohyoid membrane, vocal cords, thyroid isthmus and suprasternal notch).The laryngoscopic view was graded using Cormack and Lehane classification by anesthesia providers on the day of surgery.The data were analyzed using SPSS 19.0 software package. RESULTS: Difficult laryngoscope(Cormack-Lehane classification III-IV) was present in 17 of 141 patients. The sonographic measurements of anterior neck soft tissue were greater in the difficult laryngoscopy group compared to the easy laryngoscopy group at the level of the thyrohyoid membrane [(2.43±0.50)cm :(2.08±0.39)cm] and vocal cords [(0.98±0.21)cm :(0.87±0.20)cm] and D-value(the difference between the level of the thyrohyoid membrane and the vocal cords). The cut-off value was 2.19, 1.05 and 1.19 cm,respectively. CONCLUSIONS: Sonographic measurements of anterior neck soft tissue thickness at the level of thyrohyoid membrane, vocal cords and the D-value can be used to distinguish difficult and easy laryngoscopy.