Cardiovascular System
38
Syncope
Background
Syncope is a sudden, transient loss of consciousness due to reduced and inadequate cerebral perfusion. The incidence of syncope increases with age. Some studies showed that as many as a quarter of institutionalized elderly had this problem and the recurrence rate could be as high as 30%. The elderly is unresponsive with a loss of postural tone (ie slumps or falls). In the majority of cases, they would regain consciousness spontaneously. Secondary injury like hip fracture may occur as the elderly loses consciousness and fall. Syncope is not a disease by itself. It is a manifestation of an underlying disorder that causes reduced cerebral perfusion. Some of the important causes are: 1.Transient hypotension caused by the upright posture, straining, or coughing which is exacerbated by low circulating volume (dehydration or bleeding somewhere), hypotensive drugs or concurrent illnesses. Orthostatic hypotension (lower blood pressure on standing than lying down) is the most common cause of syncope. 2. Vasovagal response to pain, fright, emotion leading to slowing of heart beat and then hypotension. 3. Heart diseases such as myocardial infarction, arrhythmia, and aortic stenosis (narrow aortic valve opening)
Symptoms and signs
- Loss of consciousness - Pale, sweaty, absent or very weak carotid pulse - Reduced muscle tone - Possible tongue biting - Possible incontinence - Brief (few seconds) seizure activity - Brief (minutes) period of confusion may occur - Recovery is usually brisk and spontaneous
