Comparison of Laryngeal Ultrasound and Cuff Leak Test to Predict Post-Extubation Stridor in Total Thyroidectomy

Prediction of post-extubation stridor (PES) after thyroid surgeries has been challenging, and many criteria such as preoperative clinical parameters and intraoperative cuff leak test (CLT) have been used with variable results. The application of laryngeal ultrasound in predicting PES is a relatively new and non-invasive technique. Measurement of the air column width difference (ACWD) by laryngeal ultrasonography can predict PES. This study aimed to evaluate the efficacy of laryngeal ultrasound in the prediction of PES in patients after thyroidectomy and compare it with that of the CLT.

A total of 200 patients who had undergone total thyroidectomy under general anaesthesia in a tertiary healthcare hospital were enrolled in the study. At the end of the surgery, air column widths (ACWs) were measured during endotracheal cuff inflation and deflation using laryngeal ultrasound in patients with spontaneous breathing. ACWD was measured and compared with that of the CLT at the time of extubation to predict PES.

A total of 12 (6%) patients developed PES. ACWD using laryngeal ultrasound and CLT showed high sensitivity (91.7% and 92.6%, respectively), specificity (91.7% and 90.4%, respectively) and negative predictive value (99.43% and 99.42%, respectively) with low positive predictive value (44% and 37.93%, respectively) for both the diagnostic tests.

Application of laryngeal ultrasound in combination with CLT can help the anaesthesiologist in decision making with the extubation plan after thyroid surgeries.