Magnitude and Predisposing Factors of Difficult Airway during Induction of General Anaesthesia

Abstract

Objective To assess magnitude and predisposing factors of difficult airway during induction of general anaesthesia. Methods Hospital based cross sectional study carried out to determine the incidence of difficult mask ventilation, difficult laryngoscopy (Cormack and Lehane III and IV), difficult intubation (IDS ≥ 5), and failed intubation. The association between each predisposing factor and airway parameters with components of difficult airway is investigated with binary logistic regression. Sensitivity, specificity, positive and negative predictive value of the test, and odds ratio with 95% confidence interval were calculated to determine the association between independent and dependent variable. Result The incidence of difficult laryngoscopy, difficult intubation, and failed intubation are 12.3%, 9%, and 0.005%, respectively. Mouth opening < 30 mm and Mallampati classes III and IV are the most sensitive tests and second high specific test next to combination of tests to predict difficult intubation and laryngoscopy (P value < 0.001). Unrestricted multiple attempt without alternative airway techniques resulted in exponential increase in desaturation episodes and further difficulty of airway management (P value < 0.001). Discussion and Conclusion Mallampati classes III and IV, mouth opening ≤ 30 mm, jaw slide grade C, attempt > 3, and ineffective alternative technique have increased predictability value of difficult airway.

Bedside tests for predicting difficult airways: an abridged Cochrane diagnostic test accuracy systematic review

“…There were 218 test comparisons from 92 studies for difficult laryngoscopy, 72 comparisons from 50 studies for difficult intubation, 18 comparisons from seven studies for difficult facemask ventilation and two comparisons from two studies for failed intubation. Overall, the median (IQR [range]) number of participants per study, proportion of female participants, age and body mass index were 380 (200–662 [14–103,728]), 53% (44–64% [0–100%]), 45 (39–52 ) years and 27.3 (24.8–30.0 ) kg.m −2 , respectively. All studies except four performed airway management in operating theatres, two in the pre‐hospital setting and the others occurred in emergency rooms.…”

“…We identified further studies from references of retrieved articles and used citation tracking in Science Citation Index. The search was updated in March 2018 but we have not incorporated the results from 27 studies in this review.…”

Review of evidences for management of rapid sequence spinal anesthesia for category one cesarean section, in resource limiting setting

“…Difficult air way and intubation risk is more profound in pregnancy and obesity almost double risk when it is compared with other normal patients as it is supported by the systematic review [ 10 ]∗. The risk is high in pregnancy because of pregnancy related physiologic and anatomic changes such as large breast, edematous air way and frequent hypoxia, which is due to limited diaphragmatic excursion due to gravid uterus, high oxygen consumption and high risk of aspiration to have standard laryngoscopy by repeated attempts.…”

Sensitivity and Specificity of Difficult Airway Parameters at Asella Teaching and Referral Hospital, Oromia Regional State, Ethiopia

“…A study conducted in Gonder surgical hospital showed the most important predominant risk factors of difficulty airway are Mallampati classes III & IV, mouth opening < 30 mm, JSD grade C, attempt> 3, and ineffective alternative technique [13]. Generally, different parameters for the prediction of difficult airways have been studied.…”