Chapter 21: Cardiovascular System – Blood Vessels

Carry blood away from heart

Artery

Carry blood to heart

Vein

Exchange Vessel

Capillary

Small branches of arteries

Arteriole

Capillaries -> Postcapillary Venules -> Muscular Venules -> Veins

Venule

Innermost layer provides a smooth lining for blood flow

Tunica Intima

Middle layer made of smooth muscle responsible for vasoconstriction and vasodilation

Tunica Media

Outermost layer anchors blood vessels surrounding tissues

Tunica Externa

Carry blood away from heart, thicker muscle layer, smaller lumen

Arteries

Carry blood to heart, thin muscle layer, larger lumen, valves

Vein

Only Tunica Intima, simple diffusion, transcytosis, bulk flow

Capillaries

Which blood vessel serves as the body's blood reservoir? (Where is the most blood found?)

Veins

Alternate pathways that blood flows to reach tissues if the main route is blocked or narrowed

Collateral Circulation

Actual connection to reroute around blockage

Anastomosis

When does collateral circulation occur?

when a main vessel is blocked or narrowed

Where is the site of exchange within the cardiovascular system?

Capillaries

What mechanisms carry out capillary exchange?

Simple diffusion, Transcytosis, Bulk Flow

Which mechanism is the most important for capillary exchange?

Simple diffusion

From blood capillaries into interstitial fluid

Filtration

From interstitial fluid into blood capillaries

Reabsorption

What does blood hydrostatic pressure (BHP) carry out?

Filtration

What does interstitial fluid osmotic pressure (IFOP) carry out?

Filtration

What does interstitial fluid hydrostatic pressure (IFHP) carry out?

Reabsorption

What does blood colloid osmotic pressure (BCOP) carry out?

Reabsorption

How does BHP contribute to edema?

Increased pressure causes more fluid to be filtered out

How does IFOP (interstitial fluid osmotic pressure) contribute to edema?

Increased permeability of capillaries raises this and causes more fluid in space between tissue cells

How does BCOP contribute to edema?

Decreased concentration of plasma proteins lowers this which causes more fluid in space between tissue cells

What factors is venous return dependent on?

Skeletal muscle pump, Pressure gradient between veins and right atrium

What is a portal circulatory system?

Blood flows through 2 consecutive capillary beds

What are the three types of portal circulatory system

Hepatic portal system- Liver

Hypophyseal portal system- Brain

Renal portal system- Kidney

The forces involved in circulating blood throughout the body

Hemodynamics

What factors determines Ohm's Law of Fluid Dynamics?

Pressure difference, resistance, flow rate

How does the factors of Ohm's Law of Fluid Dynamics increase or decrease blood pressure?

Increased blood pressure- Increased pressure difference and increased resistance

Decreased blood pressure- Decreased resistance

Hydrostatic pressure exerted by blood on the walls of the blood vessels

Blood pressure

What systolic BP

Pressure when the heart contracts

What diastolic BP

Pressure when the heart relaxes

What type of blood vessels have high, pulsing BP?

Arteries

What determines blood pressure?

Cardiac output, blood volume

What can increase arterial blood pressure?

Vasoconstriction, higher viscosity, longer blood vessel

What is the most common artery to measure blood pressure?

Brachial Artery

What is hypotension?

Low blood pressure below 90/60 mmHg

What is hypertension?

High blood pressure 130/80

How does Neural regulate blood pressure?

Sympathetic and Parasympathetic

How does hormonal regulation control blood pressure?

Epinephrine and Norepinephrine

Q: How does autoregulation control blood pressure?

Tissues themselves release substances

Which nerve increases BP if it drops

Cardiac accelerator nerve

Which nerve decreases BP if it rises

Vagus nerves

Which hormones increase BP if it drops

Epinephrine and Norepinephrine

Which hormones decrease BP if it rises

Atrial Natriuretic Peptide

Traveling pressure waves as arteries expand and recoil

Pulse

What is the average pulse rate?

60-100bpm

What is the common pulse point for a conscious patient?

Radial

What is the common pulse point for a un conscious patient?

Carotid

Fast, bright red, spurting, most difficult to control

Arterial Spatter

Steady, tends to pool, dark red

Venipuncture

Slow and oozing, easily controlled

Capillary Bleeding

What are the most common veins used for venipuncture?

Medial cubital vein

Severe blood or fluid loss

Hypovolemic Shock

Heart fails to pump effectively

Cardiogenic Shock

Physical obstruction of blood flow

Obstructive Shock

Abnormal distribution of blood due to vasodilation

Distributive Shock

Infection leads to systemic inflammation and vasodilation

Septic Shock

Severe allergic reaction

Anaphylactic Shock

Spinal cord injury

Neurogenic Shock

Localized bulge or dilation in wall of artery

Aneurysm

Atherosclerosis of arteries in legs or arms

Peripheral Artery Disease

Arteries become narrowed and hardened due to plaque build up

Atherosclerosis

Condition where a blood clot forms in a deep vein

Deep Vein Thrombosis

Enlarged, swollen, twisted veins, often bulging

Varicose Veins

Traveling blood clot

Embolism

Blood accumulation under skin

Hematoma

Bruise

Contusion

Margot was attacked by a thief yielding a knife. In attempt to steal her purse, he sliced the anterior section of her forearm. The dark red blood steadily hemorrhaged. Which blood vessel was most likely injured?

Radial Vein

Which of the following would NOT result in an increase in arterial blood pressure?

Increase arteriolar vasodilation

Capillaries are also referred to as:

Exchange vessels

Alec had an angiogram done after his medical exam with his cardiologist. It was discovered that he actually had a clot, or thrombus, totally blocking one of his coronary arteries. Further tests showed that he had suffered minimal damage to his myocardium. What could have occurred to allow the minimal damage?

Collateral circulation

Blood that contains nutrients from digested food would pass through what vein prior to returning to the heart?

Hepatic portal vein

What later of the arterial wall is responsible for vasoconstriction?

Tunica media

Which of the following hormones would lead to a decrease in arterial blood pressure?

Atrial natriuretic peptide

Which of the following blood vessels carry blood away from the heart to other organs?

Arteries

Maureen's job entails standing on a concrete floor for 10-hour days on an assembly line. Lately she has noticed swelling in her ankles at the end of the day, some tenderness in her calves along with veins bulging from the skin. What do you suspect is Maureen's problem?

Varicose veins

A patient is overweight and has hypertension. When they sit at their office desk for a long period of time, they develop mild edema in their feet. An increase in what pressure causes more fluid to be filtered out of the capillaries into the surrounding tissues?

Blood hydrostatic pressure