Use of USG in Difficult Airway in Obese

Effectiveness of Ultrasonography for the Evaluation of Difficult Airway in Obese Patients.

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.

Study Overview

• Status: Completed
• Conditions: Obesity
• Intervention / Treatment: Other: Ultrasound

Detailed Description

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.

• Study Type: Observational
• Enrollment (Actual): 2

Contacts and Locations

Study Locations

• Turkey
  • Balıkesir, Turkey, 10145
    • Balikesir University
  • Balıkesir, Turkey
    • Medical faculty

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

obese elective surgery patients

Description

Inclusion Criteria:

• Elective surgery, ages between 18-80 BMI over 30, ASA I-II

Exclusion Criteria:

• Facial and cervical trauma, head and neck malignancy, tracheostomy and thyroid surgery, non-cooperate patients, parturients, difficult airway history.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Easy laryngoscopy; Cormack Lehane Classification 1-2a	Other: Ultrasound; Measurement of the airway by ultrasound in obese patients.
Difficult laryngoscopy; Cormack Lehane Classification 2b-3-4	Other: Ultrasound; Measurement of the airway by ultrasound in obese patients.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difficult laryngoscopy	To determine the difficult airway in obese patients with 3 levels of anterior soft tissue measurement (cm) with ultrasound.	preoperative evaluation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difficult mask ventilation	To determine the difficult airway in obese patients with 3 levels of anterior soft tissue measurement (cm) with ultrasound.	preoperative evaluation

Collaborators and Investigators

• Sponsor: Balikesir University
• Investigators: Principal Investigator: Nazan Kocaoglu, Balikesir University

Publications and helpful links

Helpful Links

• Ultrasound As A New Tool In The Assessment Of Airway Difficulties: An Observational Study.
• Development of a scoring system for predicting difficult intubation using ultrasonography

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2020
• Primary Completion (Actual): March 30, 2022
• Study Completion (Actual): August 30, 2022

Study Registration Dates

• First Submitted: May 10, 2023
• First Submitted That Met QC Criteria: June 7, 2023
• First Posted (Actual): June 9, 2023

Study Record Updates

• Last Update Posted (Actual): June 23, 2023
• Last Update Submitted That Met QC Criteria: June 21, 2023
• Last Verified: June 1, 2023

More Information

Terms related to this study

• Keywords: obesity ultrasound difficult airway
• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Overweight; Body Weight; Obesity
• Other Study ID Numbers: 2020/16

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Study Data/Documents

1. Study Protocol

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No