Zhenwei Zheng1,2, Wuhua Ma3, Ruiming Du2. 1. Department of Anesthesiology, First Clinical Medical College of Guangzhou University of Chinese Medicine, Guangzhou, China. 2. Department of Anesthesiology, Second Affiliated Hospital of Shantou University Medical College, Shantou, China. 3. Department of Anesthesiology, First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China - gzmwh@aliyun.com.
Abstract
BACKGROUND: Increased tongue volume measured by ultrasound has been proven to be related to difficult airways. Tongue volume is an indirect parameter and is derived from multiplying the midsagittal tongue cross-sectional area (CSA) by the tongue width. However, few studies have focused on the ability of tongue CSA and tongue width to predict difficult airways. This study aimed to investigate the predictive value of tongue CSA and tongue width for predicting difficult laryngoscopy and difficult intubation. METHODS: This study included 244 adult patients who underwent general anesthesia and endotracheal intubation. Demographic variables were collected, and clinical airway assessments were performed. A curvilinear low-frequency probe was used for ultrasonography, and midsagittal tongue CSA and tongue width were measured before anesthesia. The laryngoscopic view and the difficulty of intubation was graded or scored after induction of anesthesia. RESULTS: A total of 230 patients were analyzed. Twenty-eight (12.2%) patients experienced difficult laryngoscopy and twelve (5.2%) patients experienced difficult intubation. Midsagittal tongue CSA evaluated by ultrasonography could help identify patients with difficult laryngoscopy (sensitivity 0.71, specificity 0.60) and patients with difficult intubation (sensitivity 0.50, specificity 0.97). And tongue width could help identify patients with difficult laryngoscopy (sensitivity 0.39, specificity 0.89). CONCLUSIONS: Ultrasonic measurement of midsagittal tongue CSA may be a valuable predictor of difficult laryngoscopy and difficult intubation. By contrast, tongue width measured by ultrasound may be a weak predictor of difficult laryngoscopy, but its predictive ability was questionable.
BACKGROUND: Increased tongue volume measured by ultrasound has been proven to be related to difficult airways. Tongue volume is an indirect parameter and is derived from multiplying the midsagittal tongue cross-sectional area (CSA) by the tongue width. However, few studies have focused on the ability of tongue CSA and tongue width to predict difficult airways. This study aimed to investigate the predictive value of tongue CSA and tongue width for predicting difficult laryngoscopy and difficult intubation. METHODS: This study included 244 adult patients who underwent general anesthesia and endotracheal intubation. Demographic variables were collected, and clinical airway assessments were performed. A curvilinear low-frequency probe was used for ultrasonography, and midsagittal tongue CSA and tongue width were measured before anesthesia. The laryngoscopic view and the difficulty of intubation was graded or scored after induction of anesthesia. RESULTS: A total of 230 patients were analyzed. Twenty-eight (12.2%) patients experienced difficult laryngoscopy and twelve (5.2%) patients experienced difficult intubation. Midsagittal tongue CSA evaluated by ultrasonography could help identify patients with difficult laryngoscopy (sensitivity 0.71, specificity 0.60) and patients with difficult intubation (sensitivity 0.50, specificity 0.97). And tongue width could help identify patients with difficult laryngoscopy (sensitivity 0.39, specificity 0.89). CONCLUSIONS: Ultrasonic measurement of midsagittal tongue CSA may be a valuable predictor of difficult laryngoscopy and difficult intubation. By contrast, tongue width measured by ultrasound may be a weak predictor of difficult laryngoscopy, but its predictive ability was questionable.