A 52-year-old man with hypertension presents to the ENT emergency with recurrent epistaxis from the left nostril. Anterior rhinoscopy reveals bleeding from Little's area. After failed topical hemostasis with hydrogen peroxide and cotton pledgets, what is the drug of choice for chemical cauterization?

Explanation

## Chemical Cauterization in Anterior Epistaxis **Key Point:** Silver nitrate stick (75% concentration) is the gold standard for chemical cauterization of anterior epistaxis, particularly when bleeding arises from Little's area (Kiesselbach's plexus) [cite:Scott-Brown's Otolaryngology 7e Ch 18]. ### Mechanism of Action Silver nitrate causes protein denaturation and vessel thrombosis through formation of silver chloride complexes on mucosal surfaces. The reaction is rapid and reliable, with hemostasis typically achieved within 2–3 minutes of contact. ### Clinical Application - **Indications:** Anterior epistaxis refractory to conservative measures (topical hemostatics, pressure, vasoconstriction) - **Technique:** Apply the stick directly to the bleeding point under good visualization; avoid prolonged contact (>10 seconds) to prevent tissue necrosis - **Efficacy:** Success rate >90% for anterior bleeding - **Limitation:** Cannot be used for posterior epistaxis (inaccessible) ### Comparison Table | Agent | Concentration | Mechanism | Use | Drawback | | --- | --- | --- | --- | --- | | **Silver nitrate** | 75% stick | Protein denaturation + thrombosis | Anterior epistaxis (DOC) | Tissue staining, requires careful application | | Ferric sulfate | 20% solution | Hemostasis via iron-protein complex | Dental/gum bleeding | Less effective for nasal mucosa | | Potassium permanganate | 1–2% solution | Oxidative cauterization | Rarely used in ENT | Unpredictable, risk of mucosal ulceration | | Chromic acid | Solution | Coagulation necrosis | Obsolete in modern practice | Severe tissue damage, systemic toxicity | **High-Yield:** Silver nitrate is preferred over ferric sulfate in epistaxis because the nasal mucosa's high vascularity and moisture content favor the rapid action of silver nitrate; ferric sulfate is better suited to dry mucosal surfaces (gingiva, oral cavity). **Clinical Pearl:** Always apply silver nitrate with gentle pressure and avoid bilateral cauterization in the same sitting, as this risks septal perforation from ischemic necrosis. **Tip:** If silver nitrate is unavailable, topical epinephrine (1:1000) combined with pressure packing is the next best step before proceeding to anterior nasal packing.