The Application Of Ultrasonic Measurement In Predicting Difficult Airway Of Obstructive Sleepapnea Hypopnea Syndrome Patients

Objective To explore the feasibility of ultrasonic measurement of distance from median hyoid to skin,distance from combination of vocal cord level to skin and length of genitoglossus muscle for predicting difficult airway in obstructive sleep apnea hypopnea syndrome patients.Methods Thirty-seven obstructive sleep apnea hypopnea syndrome patients underwent modified palatopharyngoplasty under general anesthesia,ASA I~III level.Routine evaluation index before operation:Age,height,weight,apnea hypopnea index,the lowest oxygen saturation,neck circumference,distance from thyroid to mandibular process,distance from suprasternal fossa to mandible mental process,Mandible length,Upper and lower lip occlusal test,Modified Mallampanti airway classification,The distance from the median hyoid to the skin,the distance from the anterior union of the vocal cords to the skin,and the length of the genitoglossus muscle were measured by ultrasound.Judging if a difficult airway occurs through the exposure of a common laryngoscope,Analyzing and comparing the effects of each index onpredicting difficult airway in obstructive sleep apnea hypopnea syndrome patients.Results A total of 37 cases were included,Among them,11 cases were included in the difficult laryngoscope group and 26 cases in the non-difficult laryngoscope group.The incidence of difficult laryngoscope exposure was29.7%.The modified Mallampanti airway classification,the distance from the vocal cord level to the skin and the length of the genitoglossus muscle in the laryngoscope group were significantly different from those in the normal group(P<0.05).There were no significant differences in apnea hypopnea index,the lowest oxygen saturation,neck circumference,nail-chin distance,sternomental distance,mandible length and distance between median hyoid and skin.The area of the modified Mallampanti airway classification curve was 0.788,95% CI(0.640~0.937).And the distance from the combination to the skin before the level of vocal cords and the length of the genitoglossus muscle were below the curve area were 0.804,95% CI(0.643~0.966)and 0.788,95% CI(0.642~0.935).When the factors are combined,The area under the curve of the distance from the anterior union to the skin,combined with the length of the genitoglossus muscle is 0.864.The area under the curve of after the modified Mallampanti airway classification,the distance from the vocal cord to the skin and the length of the genitoglossus muscle were predicted by three methods is 0.955,which was significant difference in area under the length curve of genitoglossus muscle between the single factor and the distance from anterior union to skin(P <0.05).The optimal cut-off point and sensitivity specificity of the distance from the anterior vocal cord to the skin and the length of the genitoglossus muscle is0.895cm(63.6%,84.6%)and 4.09cm(81.8%,73.1%).The sensitivity and specificity of modified Mallampanti airway classification were 72.73% and73.08%.The sensitivity and specificity were 81.8% and 84.6% for the distance from anterior union to skin combined with the length of genitoglossus muscle.After a combination of three factors,the sensitivity and specificity increased to100% and 84.6%.Conclusion 1.Ultrasound measurement has a good predictive value in evaluating difficult airway of the obstructive sleep apnea hypopnea syndrome patients.2.This study suggests that if the distance from the union to the skin is greater than 0.895 cm and the length of genioglossus is less than 4.09 cm,the obstructive sleep apnea hypopnea syndrome patients can be judged to have difficult intubation.3.The accuracy of predicting difficult tracheal intubation in obstructive sleep apnea hypopnea syndrome patients can be improved by combining the distance from anterior union to skin,the length of genioglossus muscle and the modified Mallampanti airway classification.