Abstract
Background: Mask Ventilation is the most fundamental skill of airway management and it is vital for the conduct of general anaesthesia1. Difficulties with airway management in relation to general anesthesia have been a challenge for the anesthesiologist since the birth of anesthesia. Considerable improvements have been made and general anesthesia is now regarded as a safe procedure. However, difficult airway situations still occur and it causes increased risk of morbidity and mortality especially when not anticipated2.In this study we intend to analyses the incidence of Difficult and Impossible Mask Ventilation (DMV) (IMV) and the factors associated with it.
Objective: To evaluate the preoperative specified clinical airway assessment parameters on prediction of DMV and IMV.
Subjects and Methods: This study was a prospective observational study done in our institute among patients who were posted for elective surgery under general anesthesia.
Results: Two hundred patients who were mask ventilated during induction of general anesthesia were included for the study. Age >55yrs ,Body mass index(BMI) of 30kg/m2 or greater, History of Diabetes >5yrs duration ,snoring, sternomental distance (SMD)<12 cm, Edentulous status, Modified Mallampatti classification III or IV, Thyromental distance grade II & III , Upper Lip Bite Test (ULBT)class II & III were identified as significant predictors for DMV by univariate analysis.
Conclusion: In our study population, Difficult Mask Ventilation was found in 11% of the patients. Independent risk factors for DMV include body mass index > 30 kg/m2, thick obese neck, SMD<12 cm and lack of teeth. The DMV prediction may lead to a better preparedness for the management of difficult airway and also potentially decreasing the morbidity & mortality resulting from hypoxia or anoxia associated with failed ventilation.
Keywords: Difficult Ventilation; Airway; Predictors; Mask ventilation.
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Corresponding Author
Dr Bhagyalakshmi Ramesh
Regional Cancer Centre Trivandrum, India