The Evaluation of Difficult Intubation among Obese Patients by Using the Intubation Difficulty Scale (IDS) at Ratchaburi Hospital: A Descriptive Study

Main Article Content

Sumon Mantaga


Background and Objective: The Intubation Difficulty
Scale (IDS) has been used as a research tool for more
than 10 years. The objectives of this study were to describe
degree of difficult intubation defined by the Intubation
Difficulty Scale (IDS) scores, and secondly, to study the
characteristics of obese patients who were defined as
difficult intubation and the occurrence of adverse events.
Materials and Methods: This prospective study was
conducted in patients with a body mass index (BMI) of
greater than or equal to 30 kg/m2 who underwent elective
surgery by general anesthesia with endotracheal
intubation. The IDS scoring system comprised seven
parameters; the number of attempts, the number of
operators, the number of alternative technique used, the
glottic exposure defined by Cormack-Lehane grade, the
lifting force applied during laryngoscopy, the necessity for
external laryngeal pressure, the position of vocal cord. The
interpretation of difficult intubation defined by IDS scoring
system was easy intubation (IDS score 0-1), troublesome
intubation (IDS scores 2-4), and difficult intubation
(IDS scores ≥ 5).

Results: There were 136 patients enrolled; 106 females
and 26 males. The mean age ± SD was 47 years old and
the body mass index (BMI) was 34 + 3.4 kilogram /meter2
(min 30.0 kg/m 2, max 53.3 kg/m2). There were 119 patients
(87.5%) with easy intubation, 14 patients (10.3%) with
troublesome intubation and 3 patients (2.2 %, 2 female,
1 male) with difficult intubation (IDS ≥ 5). The scores
were obtained from the Cormack-Lehane laryngoscopic
view grade 3, intubation more than 1 attempt; increased
lifting force and applied external laryngeal pressure for
optimized the vocal cord exposure. There was only one
patient experienced desaturation.
Conclusions: Intubation Difficulty Scale is an easy scoring
tool for screening patient expected difficult airway. The
incidence of difficult intubation in this study when IDS ≥ 5
in obese patient was 2.2.

Article Details

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