From the Guidelines
Low blood pressure, or hypotension, is generally considered to be a blood pressure reading below 90/60 mmHg, with a systolic pressure below 90 mmHg being a critical threshold for defining hypotension in various clinical contexts, including cardiogenic shock 1.
Definition and Clinical Context
This definition is based on the most recent and highest quality study available, which emphasizes the importance of systolic blood pressure in defining hypotension, particularly in the context of cardiogenic shock 1.
- A blood pressure reading below 90/60 mmHg can cause symptoms such as dizziness, lightheadedness, fainting, blurred vision, nausea, fatigue, or confusion due to reduced blood flow to the brain and other vital organs.
- Common causes of low blood pressure include dehydration, blood loss, severe infection, certain medications, heart problems, endocrine disorders, and pregnancy.
- It's essential to note that what's considered low blood pressure can vary from person to person, and some individuals may naturally have lower blood pressure without experiencing any symptoms.
Clinical Management
If symptoms of low blood pressure occur, it's crucial to:
- Sit or lie down immediately to prevent falling
- Increase fluid intake if dehydration is the cause
- Consult a healthcare provider for proper evaluation, especially if symptoms are severe or recurrent In cases of cardiogenic shock, immediate assessment, ECG, echocardiography, and invasive monitoring with an arterial line are required, along with a fluid challenge and potentially the use of vasopressors or inotropic agents 1.
Key Considerations
- The definition of low blood pressure can vary depending on the clinical context, but a systolic pressure below 90 mmHg is a widely accepted threshold for defining hypotension.
- The management of low blood pressure depends on the underlying cause and the presence of symptoms, with a focus on restoring adequate blood flow to vital organs and preventing further complications.
From the FDA Drug Label
Patients with pre-existing sustained supine hypertension above 180/110 mmHg were routinely excluded. The FDA drug label does not answer the question.
From the Research
Definition of Low Blood Pressure
Low blood pressure, also known as hypotension, is typically defined as a systolic blood pressure of less than 90 mmHg or a diastolic blood pressure of less than 60 mmHg 2.
Symptoms and Effects
Symptoms of low blood pressure can include dizziness, lightheadedness, fainting, and fatigue. In some cases, low blood pressure can lead to inadequate blood flow to vital organs, which can cause damage or even be life-threatening.
Treatment and Management
Treatment for low blood pressure typically involves increasing blood volume and blood pressure through medication, such as fludrocortisone or midodrine, or lifestyle changes, such as increasing fluid and salt intake 3, 4, 5, 6.
- Key points about treatment:
- Fludrocortisone is a mineralocorticoid that increases blood volume and blood pressure 3.
- Midodrine is a peripheral alpha-adrenergic agonist that increases standing blood pressure and improves symptoms of orthostatism 5.
- Both fludrocortisone and midodrine have been shown to be effective in increasing blood pressure and reducing symptoms of hypotension, but may have different side effects and interactions 2, 6.
Diagnosis and Measurement
Diagnosis of low blood pressure typically involves measuring blood pressure using a sphygmomanometer or ambulatory blood pressure monitoring (ABPM) 2.
- Key points about diagnosis:
- ABPM can be used to monitor blood pressure over a 24-hour period and detect drops in blood pressure that may not be apparent with a single measurement 2.
- The number and severity of blood pressure drops can be used to assess the effectiveness of treatment and guide adjustments to medication or lifestyle changes 2.