Predicting difficult airways using the intubation difficulty scale: a study comparing obese and non-obese patients
Related Experiment Video
Updated: Jun 22, 2026

Point-of-Care Ultrasound: A Review of Ultrasound Parameters for Predicting Difficult Airways
Published on: April 7, 2023
Ronit Lavi1, Dror Segal, Avishai Ziser
1Department of Anesthesiology, Rambam Medical Center P.O.B. 9602, Haifa 31096, Israel. lavironit@hotmail.com
Study Objective:
To compare intubation difficulty in obese and non-obese patients by intubation difficulty scale (IDS), intubation duration measurement, and oxygen saturation (SaO(2)) levels.
Design:
Prospective, controlled study.
Setting:
Operating room of a tertiary-care hospital.
Patients:
204 ASA physical status I, II, and III adult patients who underwent elective surgery with endotracheal intubation.
Interventions And Measurements:
Preoperative airway parameters, intubation duration, IDS scores, and lowest SaO(2) during intubation were recorded.
Main Results:
IDS scores were higher in the obese group than the non-obese (2.29 +/- 0.45 and 1.26 +/- 0.2, respectively, P = 0.03). Intubation duration was 45.1 +/- 6 sec for obese versus 36.8 +/- 2.6 sec for the non-obese group (P = 0.20). The lowest SaO(2) recorded was 97%, with no difference noted between groups. Mallampati class >or=3 was found to positively predict intubation difficulty scores greater than 5.
Conclusions:
Difficult intubation was more prevalent among obese than non-obese patients, but intubation duration and lowest SaO(2) levels during intubation were not. Moreover, the modified Mallampati test was found to be a moderately good (60%) predictor of difficult intubation among obese patients.
Related Concept Videos
Cardiopulmonary Resuscitation V: Advanced Airway Management Techniques
Assessment of Airway, Skin Color, and Use of Accessory Muscles
Introduction
The initial evaluation of a patient's respiratory system...
Endotracheal Intubation I: Procedure
The ET tube comprises various components, including a standard adaptor to attach a bag-valve-mask (BVM) or ventilator, a cuff, a pilot balloon, and radiopaque markings along its length to measure the insertion distance. The tube sizes...
Endotracheal Tube Extubation
Procedure
Extubation removes the endotracheal tube (ETT) from the patient on mechanical ventilation. It requires a well-coordinated, multidisciplinary approach involving physicians, nurses, respiratory therapists, and other healthcare professionals.
Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History
Endotracheal Intubation II: Nursing Management
1. Nursing Care of Patients Before Intubation
Before the endotracheal intubation procedure, nurses play an essential role in ensuring the process goes smoothly. The nurses must be familiar with intubation...

