CVT 101 Vascular Unit PP Flashcards
How many miles of vasculature in the body?
There are about 60,000 miles of vasculature in the adult body.
Average diameter of cells:
0.02 mm or 20 microns
Cardiovascular system:
a pump, a series of distributing and collecting tubes, and an extensive system of thin vessels that permit rapid exchange between blood and tissues.
3 circulatory circuits:
systemic
pulmonary
and portal
(plus renal?)
Distribution of blood volume-
Venules, veins, vena cavae:
64%
What can veins do in the event of a massive hemorrhage or during exercise?
The veins can shunt blood over to the arterial side to maintain core blood pressure in the event of massive hemorrhage and to maintain blood flow during exercise.
What do Arteries do and what are they made up of?
- Carry blood away from heart
- More elastic tissue proximally, to absorb energy during systole, then put energy back into system during diastole, thus maintaining flow between heartbeats
- More smooth muscle distally, which increases arterial stiffness and resistance to flow
What does pulsatility mean?
how much it travels from the mean
What do Arterioles do and what are they made up of?
- Connect arteries with capillaries
- Large smooth-muscle component in walls
- Stopcocks of the vascular system; control of flow and resistance 4. Smooth muscle response to sympathetic nerve activity, local conditions (chemistry)
What are Capillaries and what do they do?
- Connect arterioles and venules
- Capillary beds…(not simple)
- One layer of endothelial cells
exchange of substances in and out of cells - They are very small and have no pulsatility
How big are Capillaries ans what is there transit time?
- 8 microns in diameter (~ one RBC)
- 10 billion capillaries; total surface area for exchange = 500 m2
- Transit time: 1–3 seconds, during which all diffusion must take place (diffusion rate vs. distance…)
What do Venules do and what are they made up of?
- Gather blood from capillaries and send to veins
2. No smooth muscle tissue; just endothelial and connective (i.e., just intima and adventitia)
What are Veins and what do they do?
- Return blood to heart
- Venous reservoir; capacitance; 2/3 of total blood volume at rest (some say 3/4)
- Low pressure, high volume; total CSA about 4 times that of corresponding arteries
How many leaflets do vein valves have? Where are there more valves?
Valves: two leaflets; sinus (for better function) prevent reflux site of thrombus formation
There are more valves in the lower extremities because of hydrostatic pressure.
How does the Deep system and superficial system in lower extremities work?
flow moves from superficial to deep via perforating veins with one-way valves
What are the two main superficial veins?
Great saphenous vein and the small saphenous vein
What does the Muscle pump in legs do during relaxation and contraction?
soleal sinuses (also site of thrombus formation)
When the muscle pump is relaxed the blood flows in
When the muscle pump is contracted blood flows out
What are soleal sinuses, where are they, and how do they work with the muscle pump?
they are little pouching structure in the soleals muscle that gather the venous blood and rout the blood to the posterior tibial vein where it is pushed out of the leg. The bellows of the muscle pump.
What is the Portal system and where does it start and end?
- Begins and ends as capillaries
- Connects digestive loop with liver, hepatic veins, and IVC 3. RBC–hemoglobin cycle
- this is the only loop that begins as capillaries in the digestive track and ends as capillaries in the liver.
What are the three layers of wall tissue?
- Tunica adventitia
- Tunica media
- Tunica intima
What is the Tunica adventitia?
outer layer made up of connective tissue
What is the Tunica media?
middle layer with smooth muscle cells, elastin, and collagen Composition of this layer determines the vessels’ mechanical properties
What is the Tunica intima?
smooth inner lining of vessels; single layer of endothelial cells Normally has anti-clotting, anti-platelet properties; interruption of these may start most vascular disease— both atherosclerosis and thrombosis
What is the Vasa vasorum (vessel-vessels)?
blood supply to the vascular tissue
What are the five types of vessels?
Arteries Arterioles Capillaries Venules Veins
What is blood considered to be?
An organ
What is hematocrit and what is the normal percentage?
formed particles in blood, usually about 42% ±
What are RBCs?
hemoglobin that carries O2 throughout the body
We make and destroy about 200 billion a day
What are platelets?
initiate healing process, but also initiate plaque and thrombus Thombocytopenia: heparin therapy complication
What are White cells called and what do they do?
phagocytes
They eat bad substances in the body
Landmark:
Diaphragm
The diaphragm defines the thoracic aorta from the abdominal aorta
Landmark:
Antecubital fossa
brachial artery and veins
Landmark:
Sternocleidomastoid muscle
acoustic window that allows us to scan the carotid arteries
Landmark:
Thyroid
reliable landmark for defining medial from lateral when looking at the carotid artery
Landmark:
Thoracic outlet
Over the first rib. landmark that defines the end of subclavian artery and vein and the beginning of auxiliary and vein
Landmark:
Popliteal fossa
space behind the knee where the popliteal artery and vein are
Landmark:
Medial malleolus
is your medial ankle bone used as a landmark to find the posterior tibial artery and vein
Landmark: Lateral malleolus
landmark to find the peroneal artery and veins
Landmark: Adductor canal (Hunter’s canal)
also called hunters canal. that is a channel of the muscle group in the upper thigh. superficial femeral artery and the femoral vein
Landmark: Adductor hiatus
defines the distal femoral artery and vein from the proximal popliteal artery and vein.
Landmark: Inguinal ligament
ligament that angles across the pelvic bone. The external iliac artery and vein run under it at the groin crease where they become the common femoral artery.
The external iliac is proximal and the common femoral artery is distal.
Landmark: Intermuscular sulcus
corresponds with the adductor canal. it is a groove over the medial thigh
Define Proximal/Distal
proximal is closer to
Distal is farther from
Define: Lateral/Medial
Lateral out to the side
Medial is toward the midline
Define: Cephalad/Caudal
Cephalad is toward the head
Caudal is toward the tail
Define: Superior/Inferior
Superior is above
Inferior is below
Define: Transverse
dividing the body into two parts top and bottom
Define: Sagittal
means dividing the body into left and right portions
Define: Cross-sectional
short axis
Define: Longitudinal
long axis
Define: Oblique
example: the heart, because it does not lye on any specific plane.
Its relative to all three body planes.
Define: Short axis/Long axis
Short axis is transverse and
Long axis is sagittal more or less.
