VASOVAGAL RESPONSE Meaning and
Definition
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The vasovagal response, also known as vasovagal syncope or neurocardiogenic syncope, is a common type of fainting or temporary loss of consciousness that occurs when the body overreacts to certain triggers. It is characterized by a sudden drop in heart rate and blood pressure, resulting in insufficient blood flow to the brain.
When a vasovagal response is triggered, the part of the nervous system responsible for regulating heart rate and blood pressure (autonomic nervous system) becomes imbalanced. This leads to a sudden slowing down of the heart rate (bradycardia) and dilation of blood vessels, causing a significant decrease in blood pressure. As a result, the brain does not receive enough oxygen-rich blood, leading to loss of consciousness.
Common triggers for vasovagal responses include emotional stress, fear, pain, prolonged standing, sudden changes in body position, and exposure to unpleasant sights or smells. Some individuals may experience warning signs or symptoms before fainting, such as lightheadedness, dizziness, blurred vision, sweating, and feeling warm or flushed.
In most cases, the vasovagal response is a relatively harmless condition and the person recovers spontaneously after fainting. However, it is important to identify and manage triggers to prevent injuries that may occur during loss of consciousness. Treatment may involve lifestyle modifications such as avoiding triggers, staying well-hydrated, and making gradual changes in body positions. In some cases, medication or implantable devices may be recommended to help control the condition.
Etymology of VASOVAGAL RESPONSE
The word "vasovagal response" is derived from its components: "vaso-" comes from the Latin word "vas" meaning "vessel", and "vagal" refers to the vagus nerve. The term "vasovagal" was first used in the early 20th century to describe the physiological response that involves both the blood vessels (vaso) and the vagus nerve (vagal). This response is characterized by a sudden drop in heart rate and blood pressure, leading to fainting or syncope.
