Posterior Epistaxis

Posterior epistaxis is a form of nasal bleeding in which the bleeding source is located in the posterior nasal cavity. Unlike the much more common anterior epistaxis, posterior bleeding is typically more profuse, harder to control, and can be life-threatening.

The severity of posterior epistaxis largely reflects its anatomical source. Bleeding commonly arises from branches of the sphenopalatine artery (a. sphenopalatina), a relatively large vessel supplying the posterior nasal cavity, including the region often referred to as Woodruff’s plexus. For this reason, hemostasis usually requires more advanced and invasive measures than those used for anterior epistaxis.

Aetiology and Pathophysiology

Posterior epistaxis is more common in older adults and is typically associated with systemic conditions rather than purely local nasal causes.

Main predisposing factors:

• Systemic conditions:
  • Arterial hypertension: less a direct cause than a factor that can sustain or worsen bleeding by making stable clot formation more difficult.
  • Atherosclerosis: reduces vascular elasticity and impairs effective vasoconstriction.
  • Hematologic disorders: coagulopathies and thrombocytopenia.
  • Anticoagulant and antiplatelet therapy: warfarin, aspirin, clopidogrel, and others.
• Local causes:
  • Trauma: fractures of the nasal bones and skull base fractures.
  • Tumors: neoplasms of the nasal cavity or nasopharynx (e.g., juvenile nasopharyngeal angiofibroma, carcinoma).
  • Surgery: a complication of intranasal or endoscopic sinus procedures.

Blood from a posterior source does not drain easily through the nostrils. Instead, it tends to run down the posterior pharyngeal wall. As a result, patients often swallow blood or spit it out, which is a key clinical clue.

Clinical significance

Posterior epistaxis can present quite differently from anterior bleeding and usually requires urgent medical care, often in a hospital setting.

Characteristic features:

• Blood running down the back of the throat: patients may describe a foreign-body sensation in the throat and report swallowing blood or spitting it out.
• Little or no bleeding from the nostrils: especially early on, external bleeding may be minimal.
• Bilateral bleeding: once one nasal cavity fills, blood may pass into the other and emerge from both nostrils.
• Signs of blood loss: pallor, tachycardia, dizziness, and hypotension in severe cases.
• Hematemesis: vomiting triggered by swallowed blood irritating the gastric mucosa. The vomitus may be bright red if the blood has been in the stomach briefly, or coffee-ground if it has been altered by gastric acid.

Control of posterior bleeding requires specific measures. Simple techniques such as pinching the soft part of the nose are usually ineffective. The mainstay is posterior nasal packing, using balloon catheters or gauze packs. If packing fails, management may require surgical or endoscopic techniques (endoscopic coagulation, clipping, or ligation of the sphenopalatine artery) or endovascular (angiographic) embolization.

Differential Diagnosis

The primary diagnostic task is to distinguish posterior from anterior epistaxis and to identify the underlying cause. A posterior source is suggested when blood is seen in the oropharynx on pharyngoscopy while no visible anterior bleeding point is identified on rhinoscopy. Any heavy, bilateral, or recurrent epistaxis, especially in an older patient with hypertension, should raise suspicion for posterior bleeding. After hemostasis is achieved, nasal endoscopy is recommended to exclude a neoplastic cause, particularly in recurrent unilateral episodes.