This study will evaluate how well an ultrasound measurement of the distance from the skin to the epiglottis, when combined with the modified Mallampati score, can predict difficult laryngoscopy in adult patients undergoing elective surgery under general anesthesia. Adult patients scheduled for surgery requiring tracheal intubation will be randomly assigned to two assessment strategies before anesthesia: one group will have the usual bedside airway assessment with modified Mallampati alone, and the other group will have modified Mallampati plus a quick, painless ultrasound scan of the front of the neck to measure the skin-to-epiglottis distance. During intubation, the anesthesiologist, who is blinded to the preoperative assessments, will grade the laryngoscopic view using the Cormack-Lehane classification, and the investigators will compare how accurately each assessment approach predicts difficult laryngoscopy (grade 3-4). The study does not change how anesthesia or airway management is performed; ultrasound and clinical assessments are added solely for measurement and data collection, with minimal risk to participants and potential future benefits in improving airway risk stratification and patient safety.
Adults aged 18-65 years.
ASA physical status I-II.
Scheduled for elective surgery under general anesthesia requiring tracheal intubation with direct laryngoscopy.
Able to provide written informed consent.
Emergency surgery.
Known or suspected difficult airway requiring planned alternative intubation technique (e.g., awake fiberoptic).
History of significant upper airway pathology, neck mass, prior neck surgery, or radiation affecting airway anatomy.
Limited mouth opening, cervical spine instability, or contraindication to standard sniffing position.