Correlative study between modified mallampati score with Cormack Lehane and POGO scoring

Background: Assessing the difficulty level of the airway for intubation is extremely important in anaesthetic practice to avoid delays in intubation and resulting adverse consequences. Multiple grading systems are used by anaesthesiologists across the globe to aid in classifying the airways, but the number of studies assessing the level of agreement between various methods is scarce. Hence, the current study was conducted with an objective of assessing the level of agreement of Modified Mallampatti score (MMS) with Cormack –Lehane scoring and POGO Scoring. Materials and methods: The study was a cross sectional study, conducted in the Department of Anesthesiology, Government Mohan Kumaramangalam Medical College and Hospital, Salem, Tamil Nadu on adults aged between 18 to 65 years, belonging to ASA grade 1 and 2, scheduled for elective and emergency surgery under general anaesthesia. Patients with apparent restriction of mouth opening due to pain, with fresh facial injuries and dental abnormalities were excluded from the study. The airway of each subject was assessed by the trained anesthetist, in charge of the procedure. The agreement between the different methods of grading was assessed by kappa Statistic along with its standard error and P value. P value < 0.05 was considered as statistically significant. Results: A total of 236 subjects were included in the study. Among the study population, 74 (31.36%) had mallampatti grade I. The number of mallampatti grade II, III, and IV was 140 (59.32%), 21 (8.90%) and 1 (0.42%) respectively. Among the study population, 143 (60.59%) had Cormack Lehane grade I. The number of Cormack Lehane grade II, and III was 84 (35.59%), and 9 (3.81%) respectively. Among the study population, 170 (72.03%) had POGO grade 1. The number of POGO grade 2, 3 and 4 was 42 (17.80%), 15 (6.36%), and 9 (3.81%) respectively. The measure of agreement was very poor between Mallampatti grading with Cormack Lehane grading. (kappa statistics value -0.103, P value 0.032). The measure of agreement was also very poor between Mallampatti grading and POGO grade. (kappa statistics value was 0.105, P value 0.004). The measure of agreement was fair between Cormack Lehane grading and Mallampatti grading. (kappa statistics value was 0.327, P value <0.001). Conclusions: When compared to POGO score, Cormack Lehane grading had shown a better level of agreement with Mallampatti grading. But the level of agreement between any of the two methods was too low to rely on them interchangeably in clinical practice.