Comparison of Modified Mallampati Classification With M-TAC in Difficult Airway

The term 'airway' refers to the upper airway which may be defined as the extra-pulmonary air passage, consisting of the nasal and oral cavities, pharynx, larynx, trachea and large bronchi.

The most commonly applied methods of oxygenation is ventilation through a tracheal tube, a laryngeal mask, or a face mask. Problems with tracheal intubation remain the major cause of death and disability due to anaesthesia in analyses of records of the United Kingdom medical defence societies and in the American Society of Anaesthesiologists closed claims database.

'Difficult airway' is one in which there is a problem in establishing or maintaining gas exchange via a mask, an artificial airway or both. Prediction of difficult airway management remains a pivotal challenge for anaesthesiologists because accurate prediction gets altered the potentially dangerous unanticipated airway to an anticipated difficult airway with, predominantly, ample time for proper preparation. This is helpful in reducing potential complications by the allocation of experienced personnel and by using relevant equipment and well planned strategies .

However rare, in spite of this, occurrence of difficult airway management still occurs and it prompts to increase the risk of morbidity and mortality - especially when not anticipated. Unanticipated difficulty in intubation in patients for elective surgical procedures can occur in 1.5 to 13 percent cases with none of the above mentioned abnormalities resulting in both morbidity and mortality.

Several pre-operative risk factors for assessing airway difficulties have been identified, yet none have convincing diagnostic accuracy when using in isolation. Combining several risk factors increase the predictive value of the test and multivariable risk models have been developed.

As the anatomy of the head and neck region plays a leading role in deciding the fateful profile of the airway, especially associated with influential abnormality. So, simple bedside test, such as the modified Mallampati test, has been found to be of limited value and cannot be relied on for using in predicting difficult laryngoscopy. Exclusively when each individual was investigated in isolation using a single scoring test, as it has long been realized that difficult laryngoscopy is a multifactorial problem. Thus, effective prediction requires a combination of multiple tests to provide a high index of sensitivity and specificity for prediction of difficult airway. Thus, we ventured to combine Mallampati score with some other anatomical factors (thyromental distance, anatomical abnormality and cervical mobility) to develop a new and simpler clinical prediction model for a better predictive ability.

Inclusion criteria

• -Adult patients aged 18-60 years.
• American Society of Anesthesiologists (ASA) I or II, scheduled for elective surgeries under general anaesthesia requiring endotracheal intubation

Exclusion criteria

• - Patient refusal
• ASA grade III and IV
• Cervical spine disorder
• Obstructive airway tumor
• Edentulous patients /Irregular dentition
• past history of difficult laryngoscopy and intubation.
• trauma to the airways or to the cranial, cervical, and facial regions
• history of previous surgery, burns to airways & adjacent structures
• Mouth opening<3 cm
• Age <18 years & > 60 years