Khan Zahid Hussain, Maleki Anahid, Makarem Jalil, Mohammadi Mostafa, Khan Ramooz Hussain, Zandieh Ali
Department of Anesthesiology and Intensive Care, Imam Khomeini Medical Centre, Tehran University of Medical Sciences, Tehran, Iran.
Indian J Anaesth. 2011 Jan;55(1):43-6. doi: 10.4103/0019-5049.76603.
The incidence of difficulty in tracheal intubation has been reported to range from 0.5 to 18% in patients undergoing surgery. We aimed to elucidate the role of upper lip bite test (ULBT) with other prevailing tests, hyomental/thyrosternal distances (HMD/TSD), and the mandible length (ML) and their possible correlation in predicting difficulty in intubation. After institutional approval and informed consent were obtained, 300 consecutive patients aged 20-60 years of ASA physical status I and II, scheduled for elective surgical procedures requiring tracheal intubation and meeting the inclusion criteria, were enrolled in this study. Each patient was evaluated regarding ULBT, HMD, TSD and ML. Laryngoscopy was assessed by an attending anaesthesiologist blinded to the measurements. The laryngoscopic result was graded according to Cormack and Lehane's Grading system. The negative predictive value (NPV) and positive predictive value (PPV) of ULBT were found to be 94 and 100%, respectively. These corresponding figures for TSD were 88.5 and 0%, respectively. Specificities for ULBT, HMD, ML and TSD were 100, 98.9, 98.9 and 98.1%, respectively. ULBT class and laryngoscopic grading showed the greatest agreement (kappa = 0.61, P < 0.001). An agreement between laryngoscopic grading and HMD and ML also existed (0.003 and <0.001, respectively), but was comparatively weaker. The high specificity, NPV, PPV and accuracy of ULBT as revealed in this study could be a good rationale for its application in the prediction of difficulty or easiness in intubation. ML > 9 cm and HMD > 3.5 cm were good predictors of negative difficult intubation.
据报道，接受手术的患者气管插管困难的发生率在0.5%至18%之间。我们旨在阐明上唇咬试验（ULBT）与其他常用检查（舌颏/甲状胸骨距离[HMD/TSD]）、下颌骨长度（ML）的作用及其在预测插管困难方面的可能相关性。在获得机构批准和知情同意后，本研究纳入了300例年龄在20 - 60岁、ASA身体状况为I级和II级、计划进行需要气管插管且符合纳入标准的择期手术的连续患者。对每位患者进行了ULBT、HMD、TSD和ML评估。由对测量结果不知情的主治麻醉医师评估喉镜检查情况。喉镜检查结果根据Cormack和Lehane分级系统进行分级。发现ULBT的阴性预测值（NPV）和阳性预测值（PPV）分别为94%和100%。TSD的相应数字分别为88.5%和0%。ULBT、HMD、ML和TSD的特异性分别为100%、98.9%、98.9%和98.1%。ULBT分级与喉镜检查分级显示出最大的一致性（kappa = 0.61，P < 0.001）。喉镜检查分级与HMD和ML之间也存在一致性（分别为0.003和<0.001），但相对较弱。本研究中揭示的ULBT的高特异性、NPV、PPV和准确性可能是其用于预测插管难易程度的良好依据。ML > 9 cm和HMD > 3.5 cm是阴性困难插管的良好预测指标。
