Phulli Roopali, Dey Samarjit, Maurya Indubala, Neema Praveen K, Karim Habib Md Reazaul, Kumar H N Lohith
Department of Anaesthesiology, Rajiv Gandhi Cancer Institute and Research Centre, Rohini, Delhi, India.
Department of Anaesthesiology, AIIMS, Mangalagiri, Andhra Pradesh, India.
Indian J Anaesth. 2025 Apr;69(4):372-379. doi: 10.4103/ija.ija_1066_24. Epub 2025 Mar 13.
Airway ultrasonography (USG) parameters have been used to predict difficult tracheal intubation. However, the available literature on this topic is still controversial. This study aims to assess the role of preoperative airway USG parameters, namely hyomental distance in the head neutral (HMDn), head extended position (HMDe) and their ratio (HMDR), pre-epiglottic space (PreE), and the distance from the epiglottis to the vocal cords midpoint (E-VC) and their ratio (PreE/E-VC), in predicting difficult intubation.
This prospective observational study was conducted on 190 patients. Preoperative USG airway parameters were measured. The primary outcome was to correlate these USG parameters with the Cormack-Lehane (CL) grade. The secondary outcome was to correlate these USG parameters with the intubation difficulty score (IDS). Kendall's tau correlation test and receiver operating characteristic curve analysis were performed.
A positive correlation was observed between PreE/E-VC ratio and CL grade [Kendall's tau: 0.423 (95% confidence interval (CI): 0.326, 0.513; < 0.0001], while HDMR showed a non-significant correlation with CL grade [Kendall's tau: -0.0614 (95%CI: -0.183, 0.0569); = 0.211]. PreE/E-VC ratio also showed a positive correlation with IDS [Kendall's tau: 0.391 (95%CI: 0.305, 0.471); = <0.0001), while HDMR did not show any correlation with IDS [Kendall's tau: -0.0405 (95%CI: -0.174, 0.084); = 0.409]. PreE/E-VC ratio >1.61 cm had 77.8% sensitivity and specificity of 86% to predict CL grade >2, while ratio >1.18 cm had a sensitivity of 71.7% and specificity of 76.4% to predict IDS ≥1.
The USG measurement of the PreE/E-VC ratio correlated with CL grade and IDS, while HMDR poorly correlated with CL grade and IDS and thus failed to predict difficult intubation.
气道超声检查（USG）参数已被用于预测困难气管插管。然而，关于该主题的现有文献仍存在争议。本研究旨在评估术前气道USG参数，即头部中立位时的颏下距离（HMDn）、头部伸展位时的颏下距离（HMDe）及其比值（HMDR）、会厌前间隙（PreE）、会厌至声带中点的距离（E-VC）及其比值（PreE/E-VC）在预测困难插管中的作用。
对190例患者进行了这项前瞻性观察研究。测量术前USG气道参数。主要结局是将这些USG参数与Cormack-Lehane（CL）分级相关联。次要结局是将这些USG参数与插管困难评分（IDS）相关联。进行了Kendall's tau相关性检验和受试者工作特征曲线分析。
观察到PreE/E-VC比值与CL分级之间存在正相关[Kendall's tau：0.423（95%置信区间（CI）：0.326，0.513；P<0.0001）]，而HDMR与CL分级之间的相关性不显著[Kendall's tau：-0.0614（95%CI：-0.183，0.0569）；P = 0.211]。PreE/E-VC比值与IDS也呈正相关[Kendall's tau：0.391（95%CI：0.305，0.471）；P<0.0001]，而HDMR与IDS无相关性[Kendall's tau：-0.0405（95%CI：-0.174，0.084）；P = 0.409]。PreE/E-VC比值>1.61 cm预测CL分级>2的灵敏度为77.8%，特异度为86%，而比值>1.18 cm预测IDS≥1的灵敏度为71.7%，特异度为76.4%。
USG测量的PreE/E-VC比值与CL分级和IDS相关，而HMDR与CL分级和IDS的相关性较差，因此无法预测困难插管。
