Symptoms include deep and fast respiration, weak and slow pulse, and respiratory pauses that may last for 60 seconds. Subclavian steal syndrome arises from retrograde (reversed) flow of blood in the vertebral artery or the internal thoracic artery, due to a proximal stenosis (narrowing) and/or occlusion of the subclavian artery. Symptoms such as syncope, lightheadedness, and paresthesias occur while exercising the arm on the affected side (most commonly the left). Aortic dissection (a tear in the aorta) and cardiomyopathy can also result in syncope.Various medications, such as beta blockers, may cause bradycardia induced syncope.A pulmonary embolism can cause obstructed blood vessels and is the cause of syncope in less than 1% of people who present to the emergency department. Blood pressure
Orthostatic (postural) hypotensive syncope is caused primarily by an excessive drop in blood pressure when standing up from a previous position of lying or sitting down. When the head is elevated above the feet the pull of gravity causes blood pressure in the head to drop. This is sensed by stretch receptors in the walls of vessels in the carotid sinus and aortic arch. These receptors then trigger a sympathetic nervous response to compensate and redistribute blood back into the brain. The sympathetic response causes peripheral vasoconstriction and increased heart rate. These together act to raise blood pressure back to baseline. Apparently healthy individuals may experience minor symptoms ("lightheadedness", "greying-out") as they stand up if blood pressure is slow to respond to the stress of upright posture.
Ocular rosacea is a manifestation of rosacea that affects the eyes and eyelids. Signs and symptoms generally consist of redness, irritation or burning of the eyes. Affected individuals may also feel that there is something, such as an eyelash, in the eye and frequently have redness of the nose and cheeks as well. Those who have ocular rosacea may be treated with warm compresses, artificial tears and washing the area around the eye with warm water, including the eyelids, to help relieve symptoms. Additionally, oral antibiotics, typically doxycycline, may be prescribed. Some people with ocular rosacea feel that dietary restrictions of caffeine, spicy foods, and alcoholic beverages may reduce or eliminate symptoms. Ocular rosacea may be caused by an overproliferation of the Demodex mites D. folliculorum and D. brevis, both frequently referred to as "eyelash mites". Notes
Kunimoto, Derek Y, et al. The Wills Eye Manual, 4th ed. Lippincott, Philadelphia.2004. References
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