Prelim | Structure and Function of BV Flashcards
The cardiovascular system contributes to (1) of other body systems by (2) throughout the body to deliver materials and carry away wastes.
- homeostasis
- transporting and distributing blood
Formed a closed system of tubes that carries blood away from the heart, transports it to the tissues of the body, and then returns it to the heart.
Blood vessels
Carry blood away from the heart to other organs.
Arteries
Largest arteries in the body that has the largest diameter
Elastic arteries
Elastic arteries example
aorta
pulmonary trunk
Help propel blood onward while ventricles are relaxing.
Elastic arteries
Medium-sized arteries that contains more smooth muscle and fewer elastic fibers in their tunica media.
Muscular arteries
Muscular Arteries are capable of (1) and (2) to adjust the rate of blood flow.
- greater vasoconstriction
- vasodilation
Muscular arteries examples
Brachial artery in the arm
Radial artery in the forearm
Decrease in the diameter of the lumen of a blood vessel.
Vasoconstriction
Increase in the diameter of the lumen of a blood vessel.
Vasodilation
Abundant microscopic vessels that regulate the flow of blood into the capillary networks of the body’s tissues.
Arterioles
Arteriole: Literally meaning —-
small arteries
Arterioles are known as —
resistance vessels
Play a key role in regulating blood flow from arteries into capillaries by regulating resistance, the opposition to blood flow.
Arterioles
Vasoconstriction of arterioles (1) blood pressure
Vasodilation of arterioles (2) blood pressure.
- increases
- decreases
A microscopic channel that supplies blood to the tissues themselves
Capillary
A capillary is a microscopic channel that supplies blood to the tissues themselves, a process called —
Perfusion
Types of capillaries
Continuous
Fenestrated
Sinusoids
The most common type of capillary and is found in almost all vascularized tissues.
Continuous
Characterized by a complete endothelial lining with tight junctions
between endothelial cells.
Continuous capillary
Has pores (or fenestrations) in addition to tight junctions in the endothelial lining.
Fenestrated capillary
Capillary permeable to larger molecules.
Fenestrated capillary
Least common type of
capillary
Sinusoid capillary
Flattened and have extensive intercellular gaps and incomplete basement membrane, in addition to intercellular clefts and fenestrations.
Sinusoid capillary
Drain the capilllary blood and begin the return flow of blood back toward the heart.
Venules
Types of venules
Postcapillary venule
Muscular venule
Initially receives blood from the capillaries
Postcapillary venule
Smallest venules and have loosely organized intercellular junctions.
Postcapillary venules
Function as the site of gas exchange of nutrients and wastes and white blood cell emigration
Postcapillary venules
Circularly arranged smooth muscle cells that have thicker walls across which exchanges with the interstitial fluid can no longer occur
Muscular venule
Convey blood from tissues back to the heart
Veins
Types of Veins
Anastomotic Veins
Superficial veins
Deep veins
Double sets of veins escort the arteries and connect with one another via venous channels
Anastomotic Veins
veins within the subcutaneous layer unaccompanied by parallel arteries.
Superficial veins
veins that travel between the skeletal muscle. They anastomose with the superficial veins
Deep veins
CARDIOVASCULAR (CV) CENTER in the — helps regulate heart rate and stroke volume.
medulla oblongata
Controls neural, hormonal, and local negative feedback systems that regulate BP and blood floow to specific tissues.
CV Center
CV center controls (1), (2), and (3) that regulate BP and blood floow to specific tissues.
- neural
- hormonal
- local negative feedback systems
The three main types of sensory receptors that provide input to the cardiovascular center
- Proprioceptors
- Baroreceptors
- Chemoreceptors
Monitor movements of joints and muscles and provide input to the cardiovascular center during physical activity
Proprioceptors
Monitor changes in pressure and stretch in the walls of blood vessels.
Baroreceptors
Monitor the concentration of various chemicals in the blood.
Chemoreceptors
Main blood vessels vs main vessels
Main blood vessels:
1. Arteries
2. Arterioles
3. Capillaries
4. Venules
5. Veins
Main vessels:
1. Arteries
2. Veins
Blood circulations
Pulmonary
Systemic
Venous
Aortic
Pulmonary circulation is mainly responsible for (1) and (2) to and from the heart.
- suppying oxygen
- releasing carbon dioxide
Systemic circulation is mainly responsible for (1) and vice versa
- moving blood from the heart towards the cells of the body
Systemic Circulation
- Coronary (cardiac) circulation
- Cerebral circulation
- Hepatic portal circulation
A subdivision of systemic circulation which supplies the myocardium of the heart.
Coronary (cardiac) circulation
Supplies blood to the brain
Cerebral circulation
Extends from the gastrointestinal tract to the liver
Hepatic portal circulation
Venous Circulation
- Coronary sinus
- SVC
- IVC
Receives blood from other veins superior to the diaphragm.
SVC
Receives blood from the cardiac veins and drains all the tissues of the heart.
Coronary sinus
Regions being drained by SVC
head, neck, upper limbs, and thorax.
Receives blood from veins inferior to the diaphragm.
IVC
Regions involved in IVC
abdomen, pelvis, and
lower limbs.
Aortic circulation
Ascending aorta
Arch of aorta
Thoracic aorta
Abdominal aorta
Portion of aorta that emerges from the left ventricle posterior to the pulmonary trunk.
Ascending aorta
Descends at the level of the intervertebral disc between the 4th and 5th thoracic vertebrae.
Arch of aorta
As the aorta continues to descend, it lies close to the vertebral bodies and is called —
Thoracic aorta
It descends to the level of the 4th lumbar vertebra where it divides in two common iliac arteries which carry blood to the pelvis and lower limbs.
Abdominal aorta
Choosing an appropriate site for venipuncture is crucial for a successful venipuncture.
Site selection
Important considerations in selecting which vein to use.
- location
- size
- feel of the vein
The (1) of the vein is usually the easiest from which to draw. However, do not draw at the point where (2) as there is a (3) at these junctures.
- widest, deepest part
- two veins join
- valve
SITE SELECTION
It should be (1) in order for the (2) to flow easily.
- large
- contrast agent
SITE SELECTION
The (1) is an ideal choice.
The (2) is a secondary choice.
The (3) is too close to arteries and veins to be a primary site. It can be used, but only with experienced supervision, usually a doctor.
- bend of the arm
- back of the hand
- wrist
SITE SELECTION
The veins most often used for venipuncture are located in the —.
antecubital area
Typically the order of choice in vein selection is as follows:
Median Vein
Cephalic Vein
Basilic Vein
Usually the largest and fullest vein and is best anchored by the surrounding musculature of the arm.
Median vein
Next largest and next better anchored by the surrounding musculature of the arm.
Cephalic vein
Vein close to the brachial artery so there is more risk of hitting an artery
Basilic vein
This area is often more sensitive, thus a stick is slightly more painful for the patient
Basilic vein
Site Selection
When selecting a site, never use the arm with the following:
- Scarred areas
- Side of mastectomy
- Edomatous area
- Hematoma
- Blood transfusion/ dialysis
- Fistula/ graft
- Shunt
- Decreased sensation
SHE SSD BF
Best insertion site for patient under 6 y/o
hand (dorsal. metacarpal veins)
Best insertion site for patient 6 y/o and above
basilic/ cephalic vein
Vein must be (1) (suitable for varied uses) and (2) (able to return to shape after being pressed).
- pliant
- resilient
Characteristic of a vein:
- Large enough to receive the shaft of needle.
- Visible and palpable
- Vein should be intact (not damaged).
- The vein should not be thrombosed (stationary blood clot) or tortuous (complicated vein)
CV center function
Regulate heart rate and stroke volume
