Introduction: This study was conducted to assess the accuracy of ultrasound for estimation of appropriate sized endotracheal tube. 

Methods: Patients underwent preoperative ultrasound examination during pre-anesthetic check up by an Anaesthesia Resident under guidance of an experienced ultra-sonologist. Ultrasound assessment of various diameters of trachea was done and the size of endotracheal tube inserted during surgery was noted. The data was compared with clinically used endotracheal tube size to assess the sensitivity and specificity of ultrasound. Patients were monitored post-operatively over 24 hours for the post-operative complications such as sore throat, laryngeal edema, laryngospasm, nerve injury and aspiration of gastric contents. 

Results: A significantly higher tracheal diameter and ETT size was observed for males than females. The complications reported were Sore throat (8%) and Hoarseness of voice (4%). 

Conclusion: Ultrasonography, is trusted, non-invasive method for preanesthetic estimation of the subglottic tracheal diameter selection for clinical use and validated the reliability of ultrasound for subglottic diameter avoiding complications of either trauma or inefficient ventilation.