甲颏高度预测患者困难气道的准确性

Accuracy of thyromental height in predicting difficult airway

目的评价甲颏高度预测患者困难气道的准确性。方法选择气管插管全身麻醉择期手术患者330例，性别不限，年龄〉18岁，ASA分级Ⅰ或Ⅱ级。入室后测定改良Mallampati评分（MMT）、甲颏间距、胸颏间距和甲颏高度。麻醉诱导后常规喉镜下显露声门，进行Cormack—Lehane分级。以Cormack—Lehane分级Ⅲ级或Ⅳ级定义为困难气道。采用受试者工作特征（ROC）曲线评价MMT、甲颏间距、胸颏间距和甲颏高度预测困难气道的准确性。结果甲颏高度预测困难气道的诊断阈值为39．04mm，灵敏度88．24％，特异度90．42％，曲线下面积（95％可信区间）0．897（0．859-0．928），比值比70．750。与MMT、甲颏间距和胸颏间距比较，甲颏高度预测患者困难气道的曲线下面积增大（P〈O．05）。结论甲颏高度可准确预测患者困难气道，诊断阈值为39．04mm。

Objective To evaluate the accuracy of thyromental height （TMH） in predicting diffi- cult airway. Methods Three hundred and thirty patients of both sexes requiring endotracheal intubation, aged 〉 18 yr, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ , scheduled for elective sur- gery under general anesthesia, were selected. The modified Mallampati test （MMT） score, thyromental distance （THD） , sternomental distance （SMD） and TMH were measured following admission to the oper- ating room. Direct laryngoscope was placed after induction of anesthesia to expose the glottis, and the Cor- mack-Lehane grade was recorded. Difficult airway was defined as Cormack-Lehane grade m or IV. The re- ceiver-operating characteristics curve was used to evaluate the accuracy of MMT, THD, SMD and TMH in predicting difficult airway. Results The diagnostic threshold of TMH in predicting difficult airway was 39.04 mm, the sensitivity 88.24%, the specificity 90.42%, the area under the curve （95% confidence interval） 0.897 （0.859-0.928）, and the odds ratio 70.750. Compared with MMT, THD and SMD, the area under the curve of TMH in predicting difficult airway was significantly increased （P〈0.05）. Conclu- sion TMH can accurately predict difficult airway, and the diagnostic threshold is 39.04 mm in patients.