- Definition: Blood pressure is the measurement of the force of blood pushing against blood vessel walls.
- Measurement: Measured in millimeters of mercury (mmHg).
- Components of a BP Reading:
- Systolic Blood Pressure (Top Number): Measures pressure on artery walls when the heart beats or contracts.
- Diastolic Blood Pressure (Bottom Number): Measures pressure on artery walls between beats when the heart is relaxing.
- Normal Blood Pressure: Approximately 120/80 mmHg.
Blood Pressure→
- Definition: A condition where blood pressure is consistently higher than 140/90 mmHg.
- Characteristics: The blood pushes harder against artery walls, increasing strain on the cardiovascular system.
- Diagnosis: Can be made if one or both readings (systolic or diastolic) are consistently high.
- Primary vs. Secondary:
- Primary (Essential) Hypertension: Has no identifiable cause and develops gradually over many years.
- Secondary Hypertension: Caused by an underlying condition (e.g., kidney problems) and tends to appear suddenly.
- Definition: A condition in which the force of blood pushing against the artery walls is too low.
- Characteristics: Generally defined as a blood pressure reading lower than 90/60 mmHg.
- Symptoms: May include dizziness, fainting (syncope), blurred vision, and fatigue.
- Orthostatic Hypotension: A sudden drop in blood pressure that occurs when a person stands up quickly.
Blood pressure is dynamically influenced by a combination of internal and external factors.
These are lifestyle and external factors that individuals can modify.
- Diet: High sodium intake, diet low in potassium, and excess saturated fat.
- Physical Activity: Lack of regular exercise.
- Weight: Being overweight or obese.
- Stress: High stress levels can lead to temporary increases.
- Sleep: Insufficient or poor quality sleep.
- Medications: Some medications, including cough and cold medicines, can interfere with BP control.
These are inherent or pre-existing conditions that cannot be directly modified.
- Age: The risk of high blood pressure increases with aging.
- Genetics: Family history of hypertension can increase predisposition.
- Medical Conditions: Kidney disease, thyroid problems, and obstructive sleep apnea.
Functions of Kidney→
These are internal biological mechanisms that directly influence blood pressure.
- Baroreceptors: Sensory receptors located in blood vessels that monitor blood pressure. They send signals to the brain to adjust heart rate and blood vessel constriction.
- Cardiac Output: The amount of blood pumped by the heart with each beat.
- Total Peripheral Resistance: The resistance to blood flow in the blood vessels, affected by blood vessel diameter and blood viscosity.
- Blood Volume: The total amount of blood circulating in the system.
Baroreceptors→
Adopting a heart-healthy lifestyle is crucial for managing and preventing hypertension and associated cardiac issues.
- Heart-Healthy Diet: Focus on fruits, vegetables, whole grains, and lean protein. Limit saturated and trans fats and reduce sodium intake.
- Regular Physical Activity: Aim for at least 150 minutes of moderate-intensity or 75 minutes of vigorous activity per week.
- Maintain a Healthy Weight: Calculate your Body Mass Index (BMI) to determine if you're at a healthy weight.
- Quit Smoking: Smoking damages blood vessels and significantly increases the risk of heart attack and stroke.
- Manage Stress: Use exercise, yoga, meditation, and ensure 7-9 hours of quality sleep.
| Aspect | Hypertension (High BP) | Hypotension (Low BP) | Normal BP |
|---|
| Definition | Force against arterial walls is too high | Force against arterial walls is too low | Balanced force |
| Reading | >140/90 mmHg | <90/60 mmHg | ~120/80 mmHg |
| Impact | Increased risk of heart disease, stroke, kidney damage | Dizziness, fainting, inadequate organ perfusion | Optimal cardiovascular function |