Parameswari Aruna, Govind Mithila, Vakamudi Mahesh
Department of Anaesthesiology, Critical Care and Pain Medicine, Sri Ramachandra Medical College and Research Institute, Sri Ramachandra University, Chennai, Tamil Nadu, India.
J Anaesthesiol Clin Pharmacol. 2017 Jul-Sep;33(3):353-358. doi: 10.4103/joacp.JOACP_166_17.
Difficult tracheal intubation is associated with serious morbidity and mortality and cannot be always predicted based on preoperative airway assessment using conventional clinical predictors. Ultrasonographic airway assessment could be a useful adjunct, but at present, there are no well-defined sonographic criteria that can predict the possibility of encountering a difficult airway. The present study was conducted with the aim of finding some correlation between preoperative sonographic airway assessment parameters and the Cormack-Lehane (CL) grade at laryngoscopic view in adult patients.
This was a prospective, double-blinded study on 130 patients undergoing elective surgery under general anesthesia. Preoperative clinical and ultrasonographic assessment of the airway was done to predict difficult intubation and was correlated with the CL grade noted at laryngoscopy. The sensitivity, specificity, positive predictive value, and negative predictive values of the parameters were assessed.
The incidence of difficult intubation was 9.2%. Among the clinical predictors, the modified Mallampati classification had the maximum sensitivity and specificity, and among the sonographic parameters, the skin to epiglottis distance had the maximum sensitivity and specificity to predict difficult laryngoscopy. A combination of these two tests improved the sensitivity in predicting a difficult laryngoscopy.
The skin to epiglottis distance, as measured at the level of the thyrohyoid membrane, is a good predictor of difficult laryngoscopy. When combined with the modified Mallampati classification, the sensitivity of the combined parameter was found to be greater than any single parameter taken alone.
困难气管插管与严重的发病率和死亡率相关，并且无法总是根据使用传统临床预测指标的术前气道评估来预测。超声气道评估可能是一种有用的辅助手段，但目前尚无明确的超声标准能够预测遇到困难气道的可能性。本研究旨在探寻成年患者术前超声气道评估参数与喉镜检查时的科马克-莱汉内（CL）分级之间的某些相关性。
这是一项对130例接受全身麻醉下择期手术患者的前瞻性双盲研究。对气道进行术前临床和超声评估以预测困难插管，并将其与喉镜检查时记录的CL分级相关联。评估了各参数的敏感性、特异性、阳性预测值和阴性预测值。
困难插管的发生率为9.2%。在临床预测指标中，改良马兰帕蒂分级具有最高的敏感性和特异性，而在超声参数中，皮肤至会厌距离对预测困难喉镜检查具有最高的敏感性和特异性。这两项检查联合使用可提高预测困难喉镜检查的敏感性。
在甲状舌骨膜水平测量的皮肤至会厌距离是困难喉镜检查的良好预测指标。当与改良马兰帕蒂分级联合使用时，发现联合参数的敏感性高于任何单个参数单独使用时的敏感性。
