Clinical scenario: Failed conservative management of epistaxis -- next surgical step?
Stepwise surgical escalation for epistaxis:
1. Conservative: ANP, PNP, cautery
2. Endoscopic sphenopalatine artery (SPA) ligation
3. Maxillary artery ligation
4. ECA ligation
Rationale for SPA ligation first: The sphenopalatine artery is the main arterial supply to the nasal mucosa (terminal branch of the maxillary artery). Endoscopic SPA ligation is minimally invasive with success rates >90% and avoids major surgical morbidity associated with more proximal ligation.
Why not ICA ligation? The internal carotid artery (ICA) is NEVER ligated for epistaxis because it supplies the brain and ligation causes stroke.
Why not ECA or maxillary artery first? These are reserved for cases where endoscopic SPA ligation fails, as they are more invasive procedures.
The correct next step when conservative management of epistaxis fails is endoscopic sphenopalatine artery ligation. \[\boxed{\text{Endoscopic Sphenopalatine Artery Ligation}}\]