The patient is assigned a grade according to the best view obtained.
View obtained
1. Faucial pillars, soft palate and uvula visualised
2. Faucial pillars and soft palate visualised, but uvula masked by the base of the tongue
3. Only soft palate visualised
4. Soft palate not seen.
Clinically, Grade 1 usually predicts an easy intubation and Grade 3 or 4 suggests a significant chance that the patient will prove difficult to intubate.
The results from this test are influenced by the ability to open the mouth, the size and mobility of the tongue and other intra-oral structures and movement at the craniocervical junction.