Cormack-Lehane Classification

Clinical Overview: Cormack-Lehane Grading

While the Mallampati score predicts difficulty before a procedure, the Cormack-Lehane classification describes the actual view obtained during direct laryngoscopy. It is the universal language used by anesthesiologists and emergency physicians to document the success and difficulty of an intubation.

Grading System

• Grade 1: Full view of the glottis (the vocal cords).
• Grade 2a: Partial view of the glottis.
• Grade 2b: Only the posterior extremity of the glottis or the arytenoid cartilages are visible.
• Grade 3: Only the epiglottis is visible; no part of the glottis can be seen.
• Grade 4: Neither the glottis nor the epiglottis is visible.

Practical Implications

Grade 1 views typically lead to easy intubation. Grade 3 and 4 views are considered "difficult airways" and usually require the use of adjuncts like a bougie, video laryngoscopy, or fiberoptic equipment.