Relevance of Predictors in Difficult Intubation for Patients Undergoing Maxillofacial Surgery

Objective: To determine a clinically useful variable for predicting difficult tracheal intubation in patients with seemingly normal airways. Material and Methods: In our study we had included 68 patients from September 2011 to September 2013 who needed tracheal intubation for elective maxillofacial surgery. An airway assessment test was conducted on each patient prior to general anaesthesia, with respect to mouth opening, sternomental distance, thyromental distance, oropharyngeal (Mallampati) classification and ability to protrude the mandible. After induction of anaesthesia, the laryngeal view during laryngoscopy was graded and then the ability to intubate was assessed. Results: Incidence of difficult intubation occurred in 8 (11.76%) cases out of 68 patients. Airway test that was significant for predicting difficult tracheal intubation was SMD of less than 12.5 cm, TMD of less than 6 cm, a score according to Mallampati et al. of greater than III, protrusion of mandible position B and position C and IIG less than 3 cm with sensitivity of 87.5%, 62.5%, 62.5%, 25% and 50%, respectively. Conclusion: Our study concluded that sternomental distance had the highest sensitivity of 87.5% which was statistically significant (p < 0.05) compared to other parameters.