Blood Pressure - Cardiovascular Physiology

Sphygmomanometer Placement

Placed around an artery (typically the brachial artery of the arm and the stethoscope is place distal to the cuff.

Hypertension

140/90 Chronically elevated blood pressure

Hypotension

90/60 Chronically low blood pressure

Normal Adult Blood Pressure

Ages 20-40 is 115/70 Blood pressure is lower as an adolescent and higher as we age

Inflation (Cuff)

Blocks blood flow distally in the artery

Sphygmomanometer

Blood pressure cuff

Blood Pressure

The force of blood against the inside of blood vessel walls

How should the blood pressure cuff be positioned on the patient?

The hoses on the cuff should be facing anterior (forward) and exiting the cuff distally (toward the hand)

Blood

Will only move down its pressure gradient, from high to low pressure. Therefore, adequate blood pressure must be maintained

Blood Pressure Influences

-Cardiac Output -Peripheral Resistance -Blood Volume -Body position -Exercise

Systolic Pressure

-The maximum pressure in an artery during ventricular contraction -Top number of blood pressure reading -Pressure in the arteries when ventricles contract -Recorded when the first pulsating sound is heard (when pressure in the brachial artery is sufficient to overcome pressure in the cuff, reestablishing blood flow)

Diastolic Pressure

-The minimum pressure in an artery during ventricular relaxation. -Bottom number of a blood pressure reading -Pressure in the arteries when ventricles relax -Recorded when sounds are no longer heard (because pressure in the cuff is no longer compressing the artery)

Why should the cuff not be inflated beyond 20-30 mmHg above expected value? A. Overinflation of the cuff may result in injury to the patient B. Overinflation of the cuff will result in an incorrect pressure reading C. Overinflation of the cuff will result in damage to the sphygmomanometer

A. Overinflation of the cuff may result in injury to the patient

Which of the following statements is correct? A. Diastolic pressure is recorded when Korotkoff sounds are first hear. Systolic pressure is recorded when Korotkoff sounds are no longer heard. B. Systolic pressure is recorded when Korotkoff sounds are first hear. Diastolic pressure is recorded when Korotkoff sounds are no longer heard. C. Systolic pressure is recorded 10 mmHg after Korotkoff sounds are first heard. Diastolic pressure is recorded when Korotkoff sounds are no longer heard.

B. Systolic pressure is recorded when Korotkoff sounds are first hear. Diastolic pressure is recorded when Korotkoff sounds are no longer heard. Korotkoff sounds are first heard when the pressure in the vessel is greater than the pressure in the blood pressure cuff. Korotkoff sounds are no longer heard when the pressure in the blood pressure cuff is below the lowest pressure in the vessel.

Determining Blood Pressure

Blood pressure is a combination of systolic (top) and diastolic (bottom) pressure.

Blood Pressure Maintenance

Blood pressure must be maintain for proper blood flow to tissues. Without enough blood supply, a tissue will die.

Korotkoff Sounds

Blood pressure sounds Heard from an artery as pressure is applied by a sphygmomanometer below systolic pressure.

What do you predict would happen to a person's blood pressure when they go from standing to lying down?

Blood pressure would decrease in the lying down position

What happens to the location of blood when you stand up compared to lying down?

Blood will pool in the lower limbs due to gravity. Gravity pulls blood to the lowest location in the body.

Manual Blood Pressure

Determined using sphygmomanometer and stethoscope

Why does blood pressure increase with exercise and then lower after 5 minutes?

Increased blood pressure helps to ensure muscle tissue has adequate blood supply during exercise. When exercise is over, the oxygen demand decreases.

Deflation (Cuff)

Slow deflation allows the blood to slowly flow back into the artery. The practitioner can determine systolic and diastolic pressure by listening to the blood pressure (Korotkoff) sounds

Normal expected blood pressure for an adult is less than 115/70. What do the numbers indicate when writing blood pressure?

The top number (115) is systolic pressure; the bottom number (70) is diastolic pressure. The top number indicates pressure in a vessel during ventricular contraction. The bottom number indicates pressure in a vessel during ventricular relaxation. You are now ready to take patient's blood pressure.

Cuff Orientation

Tubing faces anteriorly and exits the cuff distally

Blood Pressure Recording

Using two numbers, one on top of the other. Top is systolic, bottom is diastolic

Tissue Perfusion

blood flow through body tissues