The effect of patient positions, Sound production and neck rewind on Mallampati grading and classification to predict difficult mask ventilation in patients

 Aims and background: The difficulty of ventilation with masks is one of the most common causes of severe respiratory consequences in the field of anesthesia. Objective: To evaluate the effect of patient position, voice production and neck rejection on the Mallamapati grade, in order to predict the difficulty of ventilation with mask in patients. Materials and Methods: This research was of a prospective nature. The statistical population of this study was all candidates for surgery in Shiraz University of Medical Sciences. Sample size: A total of 500 surgical candidates aged 16-65 years old who referred to Faghihi hospital in Shiraz were enrolled in the study. The agreement between the results of the Mallamapati test in different situations was evaluated by using the agreement Kappa test. Findings: False positives and false negative are less than the rest of the states in sitting position with retractable neck back in the prediction of mask ventilation. The precision is more than other conditions in sitting position with swaying without lifting the neck in the prediction of ventilation with a mask. Seat sensitivity is considered to be greater than other conditions in the absence of backing the neck in the prediction of ventilation with a mask. Therefore, the position of sitting with swaying without lifting the neck was the best position to predict the ventilation with the mask. Conclusion: Mallampati in sitting position with pulling without retracting the neck has the highest value in predicting the difficulty of ventilation with the mask.