Pulse Rate vs Blood Pressure
Both pulse rate and the blood pressure indicate the status of the cardiovascular system, and may be confusing as both words denote the same since they share somewhat similar physiological mechanism, but they are two different entities. Pulse rate is the number of palpable expansions of the arterial wall as the blood flows through the vessel counted over a minute. Blood pressure is a measurement of force exerted by blood against the walls of the blood vessels. This article points out the differences between the two words with regard to the mechanism, the method the measurement is taken, and the pathological entities associated.
When the blood is forced out into the aorta during systole, apart from moving blood forward in the vessels, it also sets up a pressure wave that travels along the arteries, which expands the arterial walls. This expansion of the arterial wall as the blood travels is palpable as the pulse. The pulse rate is closely related to the heart rate in healthy individuals.
Pulse rate is a good indicator of the status of the circulation. Clinically it is assessed manually by counting the number of radial pulse for a full one minute when the patient is at rest and composed or using the pulseoxymeter. There are five components looked for when assessing pulse. They are pulse rate & rhythm, symmetry, character, volume, and the arterial wall thickness. These components give different clues about different disease status.
Normal pulse rate of a person is 60-100 beats per min. Rapid pulse rate is seen with a recent exercise, excitement or anxiety, shock, fever, thyrotoxicosis, and instances where the sympathetic drive is exaggerated. Slow pulse rate is seen in severe hypothyroidism and complete heart block conditions.
Blood pressure is the force exerted by blood against the walls of the blood vessels. It is calculated as;
Arterial blood pressure = cardiac output X Total peripheral resistance
Blood pressure is taken as two measurements; systolic and diastolic blood pressure where the systolic blood pressure is the maximum pressure exerted during ventricular contraction and the diastolic blood pressure is the minimum pressure exerted during ventricular relaxation.
It is measured using the sphygmomanometer. The normal blood pressure is taken as 120/80mmHg, and if it is > 140/90mmHg, it is taken as hypertension where the patient needs a regular follow up and necessary treatments, because very high-uncontrolled blood pressure can lead to organ damage.
Hypertension can be primary such as essential hypertension or secondary to some other cause such as renal disease, endocrine disease, sleep apnoea, drugs, alcohol or vasculitis. Hypotension may be resulted from cardiac failure or end stage of the shock.
What is the difference between Pulse Rate and Blood Pressure?
• Number of palpable expansions of the arterial wall counted per minute, as the blood travels through the arteries is the pulse rate, while blood pressure is calculated as cardiac output into total peripheral resistance.
• Pulse rate can be counted manually or by using a pulseoxymeter while the blood pressure is taken using the sphygmomanometer.
• In pulse rate, only one measurement is taken while, in blood pressure, two measurements are taken as systolic and diastolic pressures.
• Variations in these two entities give clues to different disease conditions.