Use of USG in Difficult Airway in Obese

Overview

Introduction and Purpose: Obesity is an increasing public health problem all over the world. Obesity is a proinflammatory multisystemic disease defined as hypertrophy and/or hyperplasia of adipose tissue. Obesity is frequently encountered in elective and emergency surgical procedures and causes more difficulties in airway management. Difficult airway, characterized by difficult mask ventilation and difficult intubation, is especially common in obese and morbidly obese patients. Some studies show that the measurement of anterior neck soft tissue thickness at the level of the vocal cords plays an important role in estimating difficult laryngoscopy in obese patients. Difficult intubation is envisaged in patients with pretracheal soft tissue thickness of 28 mm and neck circumference of more than 50 cm at the level of the vocal cord. In this prospective observational study, it is aimed to measure the preoperative anterior cervical soft tissue thickness with 3 parameters by USG in obese patients undergoing elective surgery, and to evaluate the relationship of these values with the Han Scale and Cormack-Lehane classification and their effectiveness as an indicator of difficult airway.

Materials and Methods: 157 patients who will undergo elective surgery under general anesthesia, ages between 18-80, BMI ≥ 30 kg/m2, ASA I-II were included in the study. During the preoperative evaluation, patients' gender, age, height, weight, type of surgery, BMI, neck circumference, thyromental distance (TMM), sternomental distance (SMM), hyomental distance (HMM), neck extension, mouth opening and distance between incisors were measured and tooth structure was evaluated. OSAS was evaluated based on the ASA physical condition score and AHI. Mallampati Classification was recorded. Upper lip bite test was performed. Ultrasonographic measurements were made with the patient in the supine position and the head and neck in a neutral position. The Han Scale was used to evaluate difficult mask ventilation. The laryngoscopy image was evaluated and recorded with the Cormack-Lehane Classification, and ≥2b was accepted as difficult laryngoscopy.

Conditions