Blood Pressure and Hypertension: Basic Principles

Flashcards covering the basic principles of blood pressure, cardiac output, vascular resistance, and conditions like arteriosclerosis and atherosclerosis based on Dr. Rowena W. Elliott's lecture.

Systemic Arterial Pressure

Also known as blood pressure, it is the amount of pressure placed on the arterial muscle walls to propel blood through the body.

Tissue Perfusion

The circulation of blood through tissues; it is affected when blood pressure levels are too high or too low.

Systolic

The top number in a blood pressure reading that represents systemic arterial pressure when the heart is contracting.

Diastolic

The bottom number in a blood pressure reading that represents systemic arterial pressure when the heart is not contracting.

Endothelium

A layer of the vessel structure found in arteries, capillaries, and veins.

Lumen

The internal space or cavity within a blood vessel through which blood flows.

Components of Blood Pressure

Blood pressure is the product of cardiac output and peripheral vascular resistance, expressed as $\text{BP} = \text{CO} \times \text{PVR}$.

Cardiac Output (CO)

The volume of blood the heart pumps per minute, calculated as $\text{CO} = \text{stroke volume} \times \text{heart rate}$.

Peripheral Vascular Resistance (PVR)

The force(s) opposing the movement of blood within the blood vessels, which can be affected by vessel constriction, dilation, or lumen blockages.

Stroke Volume

One of the two components multiplied to determine cardiac output.

Heart Rate

The frequency of the heartbeat, which when increased, leads to an increase in cardiac output and blood pressure.

Pulse

A synonym for heart rate used in the context of increasing cardiac output.

Impact of PVR Increase

If there is an increase in peripheral vascular resistance, there will be a corresponding increase in blood pressure.

Activity

A factor that increases heart rate.

Caffeine

A substance found in beverages like tea and energy drinks that increases heart rate.

Spicy Foods

Foods that can cause a physiologic response presenting as a high heart rate.

Capsaicin

A substance found in chili peppers that can cause the body to release adrenaline, temporarily increasing heart rate and blood pressure.

Adrenaline

A hormone released by the body in response to capsaicin that increases heart rate and blood pressure.

High-fat foods

Foods that take longer to digest, which can cause the heart to beat faster and irregularly.

Factors Increasing Blood Volume

Increased fluid intake (orally or parenterally), hormones like aldosterone, and drugs such as NSAIDs.

Aldosterone

A hormone identified as a factor that increases blood volume.

NSAIDs

Non-steroidal anti-inflammatory drugs that can cause fluid retention, thereby increasing blood volume.

Fluid Retention

A condition caused by NSAIDs that leads to increased blood volume.

Blood Viscosity

The thickness of the blood; an increase in this factor leads to an increase in peripheral vascular resistance.

High Altitude

An environmental factor that increases blood viscosity.

Dehydration

A physiological state that increases the thickness of the blood.

Diuretics

A type of medication that can increase blood viscosity.

Erythropoetin

A medication that can increase blood viscosity/thickness.

Lumen Reduction Factors

Anything that decreases the blood vessel lumen, such as blood clots, plaque, congenital defects, or tumors.

Thrombus

A type of blood clot that decreases the blood vessel lumen.

Embolus

A type of blood clot that specifically causes the vessel lumen to become narrower.

Plaque

A substance associated with hyperlipidemia that decreases the blood vessel lumen.

Hyperlipidemia

A condition involving high lipid levels that contributes to the formation of plaque in blood vessels.

Congenital defects

Structural issues present from birth that can decrease the blood vessel lumen.

Tumors

Growths that can externally decrease the lumen of a blood vessel.

Arteriosclerosis

The hardening and thickening of the arterial smooth muscle resulting in a loss of elasticity.

Causes of Arteriosclerosis

Factors include older age, diabetes mellitus, or plaque deposits.

Atherosclerosis

Hardening of the arterial walls specifically due to plaque deposits in the lumen.

LDL cholesterol

A type of fat that commonly comprises the plaques found in atherosclerosis.

Fibrin

A fibrous protein that, along with LDL cholesterol, comprises the plaques in atherosclerosis.