An understanding of nasal anatomy is essential for successful management of epistaxis. The internal and external carotid artery systems provide the nasal cavity with the blood supply necessary to warm and humidify incoming air. The anterior and posterior ethmoid arteries, branches of the ophthalmic artery, originate from the internal carotid system and primarily perfuse the anterior and middle septa and the superior-lateral nasal cavity. The external carotid artery supplies the majority of the nasal vasculature via the sphenopalatine and greater palatine branches of the internal maxillary artery. They supply the lateral nasal wall and posterior septum. The superior labial artery, a branch of the facial artery, also has its origin from the external carotid system. The two carotid systems communicate extensively at Kiesselbach’s plexus in Little’s area located on the anterior cartilaginous septum. Over 90% of nosebleeds result from spontaneous or traumatic rupture in this plexus.

A complete history includes questions regarding side of bleeding, precipitating events, frequency, duration, predisposing medical conditions, and previous attempts at treatment. Blood loss and symptoms of hypovolemia should be ascertained to assess whether intravenous fluid or blood resuscitation is indicated. A thorough medication history should be obtained, including the use of anticoagulants, nonsteroidal antiinflammatory agents, and toxic chemical agents, as well as homeopathic remedies. Laboratory studies may be indicated based on the history and physical examination.

Some of the causes of epistaxis are listed in Table 17-1. These can be classified as local or systemic in nature.