A Comparative Study On The Evaluation Method Of Difficult Airway Based On Ultrasonography And SARI Score

Objective:1.To evaluate the effectiveness of Simplified Airway Risk Index(SARI)score in predicting difficult Airway in Chinese patients.2.Anatomic data of the upper airway were measured by ultrasound and compared with SARI score to evaluate the effectiveness of the two methods in predicting difficult airway.Methods:The first part:800 patients who underwent elective surgery and underwent laryngoscope exposure tracheal intubation under general anesthesia in the operating room of Yijishan Hospital,411 males and 389 females,the age range is 18 to 90 years old,were selected in the study.SARI score was performed for patients before anesthesia.The software is used to depict the receiver operating characteristic curve(ROC)and calculate the area under the curve(AUC).The AUC was used to evaluate the validity of SARI score in predicting difficult laryngoscopy exposure and difficult tracheal intubation.Youden index was used to determine the best boundary value of SARI score in predicting difficult airway.The second part:1000 patients who underwent elective surgery and underwent laryngoscope exposure tracheal intubation under general anesthesia in the operating room of Yijishan Hospital,519 males and 481 females,the age range is 18 to 90 years old,were selected inthe study.SARI score was performed for the patients before anesthesia,and the specific score was calculated.Meanwhile,the hyoid mental distance,tongue thickness and mandibular condyle mobility were measured under ultrasound.After anesthesia induction,laryngoscope was used to expose the glottis and insert the tracheal catheter.Routine laryngoscope exposure grades and the number of tracheal catheter insertion were recorded.The primary observation point was difficult tracheal insertion and the secondary observation point was difficult laryngoscopic exposure.The Odds Ratio(OR),sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV),and their respective 95% Confidence Interval(95% CI)of the parameters measured by ultrasound in predicting difficult tracheal intubation and difficult laryngoscopy exposure were statistically analyzed.Youden index was used to determine the best predicted boundary value of each parameter measured by ultrasonography.Multiple Logistics regression analysis was used to create a ultrasonic evaluation method prediction of difficult catheter insertion and difficult laryngoscope exposure.Multiple Logistics regression analysis was used to create an evaluation method for ultrasonic prediction of difficult catheter insertion and difficult laryngoscopy exposure.The ultrasonic evaluation method was compared with the SARI score,and we evaluate the validity of the two methods.Results:The first part: 800 patients were selected in the study.There were 20 cases of difficult tracheal intubation,the proportion was 2.50 percent and 40 cases of difficult laryngoscopy,the proportion was 5.00 percent.Among the seven assessment factors of SARI score,there was no significantly different in body weight between difficult laryngoscopy exposure and difficult tracheal intubatio(P=0.98 and P=0.85),and none of the included patients had a history of difficult intubation.Another five predictors were significantly different in difficult and non-difficult airways(P<0.001).The ROC value of SARI score for difficulty tracheal intubation was 0.90(95% CI 0.87~0.92)and difficultylaryngoscopy exposure was 0.81(95% CI 0.78~0.83).The best prediction criteria for predicting difficult laryngoscopic exposure and difficult tracheal insertion determined by Youden index were both SARI score >3.The second part: 1000 patients were selected in the study.There were 26 cases of difficult tracheal intubation,the proportion was 2.60 percent and 52 cases of difficult laryngoscopy,the proportion was 5.20 percent.The ROC of difficult tracheal insertion and difficult laryngoscopy assessed by SARI score were 0.87(95% CI 0.85~0.89)and0.80(95% CI 0.77~0.82).The ROC of difficult tracheal insertion was assessed by the ultrasonic evaluation method was 0.89(95% CI 0.86~0.90),and the ROC of difficult laryngoscopy was 0.85(95% CI 0.82~0.87).The ROC of difficult tracheal insertion predicted by ultrasonic evaluation method was higher than that by SARI scoring method,but the difference was not significant(P=0.74).The ROC of difficult laryngoscopy exposure predicted by ultrasonic assessment method was higher than that by SARI scoring method,and the difference was not significant(P=0.20).Conclusion:1.SARI score is effective in predicting difficult tracheal intubation and difficult laryngoscopy in Chinese patients,but the predictive efficacy of body weight was not ideal.2.The effect of ultrasonic evaluation method in predicting difficult airway is similar to that of SARI scoring method.