Increased conduit vessel stiffness results in increased characteristic impedance of the aorta and decreased arterial compliance, which cause an increase in systolic blood pressure (SBP) and pulse pressure as well as a decrease in diastolic blood pressure (DBP).
Local trauma is the most common cause, followed by facial trauma, foreign bodies, nasal or sinus infections, and prolonged inhalation of dry air. Children usually present with epistaxis due to local irritation or recent upper respiratory infection (URI).
Epistaxis Bleeding from the nose that may be caused by dry air, an injury, medication to prevent blood clotting, or high blood pressure; also known as a nosebleed. Hemoptysis The expectoration of blood or bloodstained sputum derived from the lungs or bronchial tubes as the result of pulmonary or bronchial hemorrhage. Hemothorax A collection of blood in the pleural cavity hypercapnia The abnormal buildup of carbon dioxide in the blood.