Alternate Names: Hypotension; Low blood pressure
Considerations: The blood pressure is normally above 90/60 mmHg (millimeters of mercury). When the blood pressure is too low there is inadequate blood flow to the heart, brain, and other vital organs.
Borderline low blood pressure for one person may be normal for another. The most important factor is how the blood pressure changes from the baseline or normal condition. A fall of 30 mmHg or more from a person’s baseline is considered low blood pressure.
Common Causes:
- shock
- stress or trauma
- response of blood vessels to stimulation of the vagus nerve-- called vasovagal syncope (common faint)
- sudden change in body position, usually from lying down to an upright position (orthostatic hypotension)
- allergic reaction to drugs
- anaphylaxis (a life-threatening allergic response)
- dehydration
- drugs including alcohol toxicity, anesthesia, antianxiety agents, antihypertensives, calcium channel blockers, diuretics, general anesthetics, antiarrhythmics, monoamine oxidase inhibitors, narcotic analgesics, tranquilizers, vasodilators
Home Care: Follow prescribed therapy. Bed rest and some assistance with all activities may be recommended (at least until the condition improves).
Call If:
- there is any sudden drop in blood pressure (shock often accompanies trauma or injury). Call an ambulance or your health care provider immediately, and administer first aid.
- there is persistent and unexplained low blood pressure (which may manifest itself by unexplained fainting spells).
- fainting or loss of consciousness occurs. Call an ambulance or your health care provider immediately, and administer first aid.
What To Expect: In emergencies, the condition will be stabilized first. Then, a history will be obtained and a physical examination performed. Frequent monitoring of vital signs (temperature, pulse, rate of breathing, blood pressure) will be necessary.
Medical history questions documenting low blood pressure include:
- What is the blood pressure?
- What is the person’s normal blood pressure?
- What medications does the person take?
- Has the person been eating and drinking normally?
- Is there any recent history of illness, accident, or injury?
- What other symptoms were also present?
- Did the person faint or become less alert?
Diagnostic tests that may be performed include:After seeing your health care provider:
You may want to add a diagnosis related to low blood pressure to your personal medical record.
