ULBT

Q: What is the utility of the upper lip bite test (ULBT)?

Answer: Assessing the ability to sublux the mandible during intubation.

ULBT is an easy test to perform prior to intubation/lаrуոgοѕϲοpy. It helps assess the ability to sublux the mandible (mandibular protrusion) before attempting lаrуոgοѕϲοpy. Though it can be quickly evaluated by asking the patient to protrude the lower jaw to bring mandibular teeth in front of the maxillary teeth, ULBT can do it more objectively by grading it into three levels.

The patient is asked to reach and cover the upper lip with lower incisors.

Grade 1: The patient can fully cover the upper lip with lower incisors

Grade 2: The patient can partially cover the upper lip with lower incisors

Grade 3: The patient cannot reach the upper lip with lower teeth

#procedures

References:

1. Eberhart LH, Arndt C, Cierpka T, et al. The reliability and validity of the upper lip bite test compared with the Mallampati classification to predict difficult laryngoscopy: an external prospective evaluation. Anesth Analg 2005; 101:284.

2. Khan ZH, Mohammadi M, Rasouli MR, et al. The diagnostic value of the upper lip bite test combined with sternomental distance, thyromental distance, and interincisor distance for prediction of easy laryngoscopy and intubation: a prospective study. Anesth Analg 2009; 109:822.