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Definition

Epistaxis is the presence of hemorrhage from the nares.

Risk factors

 Inexperience, although hemorrhage may occur with skillful intubation in a compliant horse

 Non‐compliant horse

Pathogenesis

Epistaxis is the most common complication from nasogastric intubation [1–3]. Hemorrhage can occur when the respiratory mucosa, nasal turbinates, or ethmoid turbinates are traumatized.

Prevention

The risk of epistaxis may be minimized by careful and gentle technique and assuring advancement of tube into ventral nasal meatus using well‐lubricated tubes that are in good condition and free of external defects or roughening. Tube diameter should be selected to be an appropriate size for the patient, with the dimensions of the ventral nasal meatus being most limiting. Although water often provides sufficient lubrication in most circumstances, additional lubrication using carboxymethylcellulose or lubricating gel at the end of the tube may reduce risk of epistaxis in small patients, patients with dry or friable mucosa, or animals with restricted nasal passages. Pre‐emptive intranasal application of phenylephrine spray, which causes local vasoconstriction of vessels within the nasal mucosa, may be of benefit. Patients should be adequately restrained, which may require use of a nose twitch or sedation.

Diagnosis

Epistaxis occurs during placement or immediately after removing the nasogastric tube.

Treatment

Mild elevation of the head may speed resolution of bleeding, because lowering the head increases venous congestion, which would delay hemostasis. Extreme elevation of the head should be avoided because it increases the risk of aspiration and pneumonia [1]. Packing of the affected nasal cavity is an option, but the technique may simply divert hemorrhage into the nasopharynx and not reduce the volume of bleeding. Intranasal application of phenylephrine or epinephrine may be useful in providing local vasoconstriction; however, ongoing bleeding may limit the amount and distribution of drug that is absorbed by the nasal mucosa.

Expected outcome

Bleeding may be minor or more significant, and is usually self‐limiting [2]. In rare circumstances, hemorrhage may be severe enough to require blood transfusion and the administration of drugs to promote coagulation and prevent fibrinolysis. It is recommended that horses should not be anesthetized while there is ongoing nasal hemorrhage, because the head is generally positioned lower than the heart during anesthesia, which would exacerbate hemorrhage, and the cardiovascular consequence of ongoing blood loss is less tolerated during the cardiovascular depressant effects of most anesthetic drugs.