Pre‐operative voice evaluation as a hypothetical predictor of difficult laryngoscopy

• Published in: Anaesthesia 2019-09, Vol.74 (9), p.1147-1152
• Main Authors: Carvalho, C. C., Silva, D. M., de Carvalho Junior, A. D., Santos Neto, J. M., Rio, B. R., Neto, C. N., Orange, F. A.
• Format: Article
• Language: English
• Subjects: Acoustics; Adult; Anesthesia; Anesthesia, General; Classification; difficult airway algorithm; Female; Humans; Intubation; Intubation, Intratracheal - methods; laryngoscopic view: grading; Laryngoscopy; Laryngoscopy - methods; Male; Medical instruments; Middle Aged; Multivariate analysis; Phonemes; Predictive Value of Tests; predictor patients who were difficult to intubate; Preoperative Care - methods; Prospective Studies; Regression analysis; Regression models; Respiratory tract; Statistical analysis; Surgery; Voice; Voice - physiology
• ISSN: 0003-2409; 1365-2044
• DOI: 10.1111/anae.14732

Summary We examined the potential for voice sounds to predict a difficult airway as compared with prediction by the modified Mallampati test. A total of 453 patients scheduled for elective surgery under general anaesthesia with tracheal intubation were studied. Five phonemes were recorded and their formants analysed. Difficult laryngoscopy was defined as the Cormack–Lehane grade 3 or 4. Univariate and multivariate logistic regression were used to examine the association between some variables (mouth opening, sternomental distance, modified Mallampati and formants) and difficult laryngoscopy. Difficult laryngoscopy was reported in 29/453 (6.4%) patients. Among five regression models evaluated, the model achieving better performance to predict difficult laryngoscopy, after a variable selection criteria (stepwise, multivariate) and included a modified Mallampati classification (OR 2.920; 95%CI 1.992–4.279; p