The Predictor of Respiratory Discomfort After the Shoulder Arthroscopic Surgery as Measured by Upper Airway Ultrasonography

During shoulder arthroscopic surgery, extravasation of irrigation fluid can occur around the shoulder and trachea, compressing the upper airway. Although the extravasation is generally reabsorbed asymptomatically within 12 hours, there are cases that lead to reintubation or life-threatening complications.

An endotracheal tube is the most reliable method of securing the airway from airway obstruction during a shoulder arthroscopy surgery. However, since the airway may become obstructed after extubation, airway patency should be verified before extubation. Direct visualization of the larynx or trachea using laryngoscopy or bronchoscopy is difficult due to the presence of the tracheal tube. A cuff leak around the tracheal tube in a cuff-deflated condition is suggested to be a predictor of successful extubation. However, its reliability has been questioned in adult patients. A cuff leak could be affected by paratracheal pressure, which is thought to be elevated during shoulder arthroscopy. In a recent study, it was shown that laryngeal ultrasound can be a reliable, non-invasive method for the evaluation of laryngeal morphology or predicting post-extubation stridor.

The investigators applied upper airway ultrasonographic examination focusing the measurement of upper airway diameters in patients undergoing shoulder arthroscopic surgery to evaluate the change of upper airway anatomy before and after the surgery. The investigators also tried to find any findings of ultrasonographic examination that could reliably predict the dyspnea or airway compression after extubation. The investigators tried to compare the ultrasonographic findings with those of chest radiograph to validate the measurements of the ultrasonographic examination. A cuff leak test was preformed to evaluate its ability to predict the upper airway obstruction in shoulder arthroscopic surgery.