Introduction to Blood Pressure
Blood pressure (BP) refers to the force exerted by circulating blood on the walls of blood vessels. It is a critical parameter in evaluating cardiovascular health. Blood pressure is typically measured in millimeters of mercury (mmHg) and is expressed as two numbers: systolic pressure (upper value) and diastolic pressure (lower value).
Who Discovered Blood Pressure?
The concept of blood pressure was first studied by Stephen Hales, an English clergyman and scientist, in 1733. He was the first to measure blood pressure in animals using a tube inserted into an artery. Later, instruments like the sphygmomanometer were developed by Scipione Riva-Rocci (1896) and improved by Nikolai Korotkoff (1905), who introduced the auscultatory method to measure BP in humans.
Systolic Pressure
• Definition: The pressure in the arteries when the heart’s ventricles contract and pump blood out to the body.
• Significance: Indicates the maximum pressure during a heartbeat.
• Normal Range: Usually ranges between 90-120 mmHg in healthy adults.
Diastolic Pressure
• Definition: The pressure in the arteries when the heart is at rest between beats.
• Significance: Reflects the minimum pressure in the arteries.
• Normal Range: Usually ranges between 60-80 mmHg in healthy adults.
Dr.-Approved Blood Pressure Range in India (Age-Wise)
Age Group | Normal Range (mmHg) | High BP (Hypertension) | Low BP (Hypotension) |
Children (1–12) | 80-110 / 50-70 | >120 / 80 | <80 / 50 |
Teenagers (13–19) | 90-120 / 60-80 | >130 / 85 | <85 / 55 |
Adults (20–59) | 90-120 / 60-80 | >140 / 90 | <90 / 60 |
Seniors (60+) | 110-140 / 70-90 | >150 / 90 | <100 / 60 |
Note: Values may vary slightly based on lifestyle, health conditions, and medical guidelines.
Step-by-Step Procedure to Measure Blood Pressure
1. Prepare the Patient:
• Ensure the patient is relaxed and seated for at least 5 minutes.
• Avoid caffeine, smoking, or exercise 30 minutes before measurement.
2. Choose the Right Equipment:
• Use a properly calibrated sphygmomanometer or an automated BP monitor.
• Select the correct cuff size (covers 80% of the arm circumference).
3. Position the Patient:
• Sit upright with back supported and feet flat on the floor.
• The arm should rest on a table at heart level, palm facing upward.
4. Place the Cuff:
• Wrap the cuff snugly around the upper arm, 1–2 cm above the elbow crease.
• Ensure the cuff’s tube aligns with the brachial artery.
5. Inflate and Deflate the Cuff:
• Inflate the cuff until the dial reads 20–30 mmHg above the expected systolic pressure.
• Slowly release the pressure while listening for Korotkoff sounds (first = systolic, last = diastolic).
6. Record the Readings:
• Record the systolic and diastolic readings.
• Repeat the measurement after 1–2 minutes for accuracy.
Precautions During Blood Pressure Check-Up
• Ensure the arm is relaxed and not tensed.
• Avoid talking or moving during the measurement.
• Take measurements at the same time daily for consistency.
• Measure BP on both arms initially; use the arm with higher readings for subsequent checks.
• Keep the room quiet and at a comfortable temperature.
References
1. World Health Organization (WHO) Guidelines on Hypertension.
2. American Heart Association (AHA) Recommendations for BP Measurement.
3. Indian Heart Association: Hypertension Management Guidelines.
4. National Health Portal India: Blood Pressure Standards.
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