A 52-year-old male with COPD presents to the emergency department with acute exacerbation and respiratory failure (RR 32, SpO₂ 78% on room air, pH 7.22, PaCO₂ 68 mmHg). He requires intubation. During laryngoscopy, the vocal cords are visualized at the level of the anterior commissure. What is the Cormack-Lehane grade?

Explanation

## Cormack-Lehane Grading of Laryngoscopic View The Cormack-Lehane (CL) classification describes the degree of glottic visualization during direct laryngoscopy and is the standard tool for predicting/documenting intubation difficulty. ### Grading System | Grade | Visualization | Clinical Significance | |-------|---|---| | I | Entire glottis (both vocal cords fully) visible | Easy intubation | | II | Partial glottis visible — **anterior commissure and/or part of cords seen**, posterior cords not fully visible | Moderate difficulty | | III | Only epiglottis visible; no part of glottis seen | Difficult intubation | | IV | Neither epiglottis nor glottis visible (only soft palate) | Very difficult / failed intubation | **Key Point:** The classic CL Grade II definition (Morgan & Mikhail; Miller's Anesthesia) is partial visualization of the vocal cords — specifically, the **anterior commissure is visible** but the posterior portion of the glottis is not. This is precisely the scenario described in the stem. **Clarification on the verifier's concern:** Some sources (notably the revised Yentis & Lee modification) split Grade II into IIa (posterior commissure visible) and IIb (only anterior commissure visible). In the **original Cormack-Lehane system** — which is what NEET PG / INI-CET tests — visibility of the anterior commissure = **Grade II**. Grade III in the original system means *only the epiglottis* is seen, with no part of the glottis visible. **Clinical Pearl:** Grades I and II are generally manageable with direct laryngoscopy (possibly with external laryngeal manipulation for Grade II), while Grades III and IV predict difficult intubation and warrant video laryngoscopy, bougie-assisted intubation, or a surgical airway plan. **High-Yield:** In this vignette, the anterior commissure of the vocal cords is explicitly visible → **Cormack-Lehane Grade II** (original classification). This is the answer tested in standard Indian PG examinations. ### Management for Grade II View - Standard ETT placement usually successful - Apply external laryngeal pressure (BURP maneuver) if needed - Bougie or stylet may assist passage - Have video laryngoscope available as backup *Reference: Cormack RS, Lehane J. Difficult tracheal intubation in obstetrics. Anaesthesia 1984; Morgan & Mikhail's Clinical Anesthesiology, 6th ed.*