Quyen Lee

Date of Award


Document Type

Independent Study

Degree Name

Master of Science (MS)


Background: Morbid obesity is increasingly prevalent. Tracheal intubation in this patient population may be hampered by factors such as limited neck extensibility, redundant soft tissue in the neck, chest, and pharynx. It is unclear whether traditional clinical predictors of difficult intubation, such as Mallampati's classification, remain valid for the more obese patient population today. The purpose of this study is to review the current literature to clarify whether Mallampati's classification, first described in 1985, is relevant in the more obese population today. This study is a literature review of morbidly obese adult patients undergoing general anesthesia. A Pub Med search conducted on May 21 , 201 I limited to the English language and humans was performed using a combination of the following terms: difficult intubation, morbid obesity, Mallampati, and Cormack-Lehane. Articles were screened for relevance and reviewed to summarize the findings. Conflicting data exist regarding the role of a high body mass index (BMI) and difficult intubation. Many studies find that a high BMI is correlated with increased neck circumference, Mallampati class, and Cormack-Lehane scores. Whether a difficult laryngoscopy is equivalent to a difficult intubation is not clear. Nurse anesthetists planning to provide general endotracheal anesthesia in the increasingly obese patient population may not rely solely on older metrics such as preoperative Mallampati classifications. Morbidly obese patients must be approached with a high index of suspicion since an unexpected difficult tracheal intubation could be disastrous.