Ch. 9 Vascular System Flashcards
Tiny arteries and veins that supply the walls of blood vessels
vasa vasorum
Inner layer of the vascular system
tunica intima
Minute vessels that connect the arterial and venous systems
capillaries
Communication between two blood vessels without any intervening capillary network
anastomosis
Outer layer of the vascular system, contains the vasa vasorum
tunica adventitia
Middle layer of the vascular system; veins have thinner tunica media than arteries
tunica media
Arises from the posterolateral wall of the aorta, travels posterior to the inferior vena cava to supply the kidney, stomach and lower third of the esophagus
left gastric artery
Supplies the gallbladder via the cystic artery
right hepatic artery
Vascular structures that carry blood away from the heart
arteries
Arises from the celiac trunk to supply the liver
common hepatic artery
Supplies the stomach
right gastric artery
Branch of the common hepatic artery that supplies the stomach and duodenum
gastroduodenal artery
Arises inferior to the celiac axis to supply the proximal half of the colon and the small intestine
superior mesenteric artery
The abdominal aorta bifurcates at the level of the umbilicus into these, which supply blood to the lower extremities
common iliac arteries
Arises from the anterior aortic wall at the level of the third or fourth lumbar vertebra to supply the left transverse colon, descending colon, sigmoid colon, and rectum
inferior mesenteric artery
Arises from the posterolateral wall of the aorta directly into the hilus of the kidney
left renal artery
Largest arterial structure in the body; arises from the left ventricle to supply blood to the head, upper and lower extremities, and abdominopelvic cavity
aorta
Small branch supplying the caudate and left lobes of the liver
left hepatic artery
Arises from the celiac axis to supply the spleen, pancreas, stomach, and greater omentum
splenic artery
Drains the spleen; travels horizontally across abdomen (posterior to the pancreas) to join the superior mesenteric vein to form the portal vein
splenic vein
Collapsible vascular structures that carry blood back to the heart
veins
Formed by the union of the superior mesenteric vein and splenic vein near the porta hepatis of the liver
portal vein
Drains the left third of the colon and upper colon and joins the splenic vein
inferior mesenteric vein
Drains the proximal half of the colon and small intestine travels vertically (anterior to the inferior vena cava) to join the splenic vein to form the portal veins
superior mesenteric vein
Three large veins that drain the liver and empty into the inferior vena cava at the level of the diaphragm
hepatic veins
Leaves the renal hilum, travels anterior to the aorta and posterior to the superior mesenteric artery to enter the lateral wall of the inferior vena cava
left renal vein
Largest venous abdominal vessel that conveys blood from the body below the diaphragm to the right atrium of the heart
inferior vena cava
Leaves the renal hilum to enter the lateral wall of the inferior vena cava
right renal vein
Disease of the arterial vessels marked by thickening, hardening, and loss of elasticity in the arterial walls
arteriosclerosis
Condition in which the aortic wall becomes irregular from plaque formation
atherosclerosis
Tear in the intima or media of the abdominal aorta
dissecting aneurysm
Permanent localized dilation of an artery, with an increase of 1.5 times its normal diameter
aneurysm
Periportal collateral channels in patients with chronic portal vein obstruction
cavernous transformation of the portal vein
Circumferential enlargement of a vessel with tapering of both ends
fusiform aneurysm
Weakening of the arterial wall
cystic medial necrosis
Pulsatile hematoma that results from leakage of blood into soft tissue abutting the punctured artery with fibrous encapsulation and failure of the vessel wall to heal
pseudoaneurysm
Transjugular intrahepatic portosystemic shunt
TIPS
Most commonly results from intrinsic liver disease; however, also results from obstruction of the portal vein, hepatic veins, inferior vena cava, or prolonged congestive heart failure; may cause flow reversal to the liver, thrombosis of the portal system, or cavernous transformation of the portal vein
portal venous hypertension
Communication between an artery and a vein
arteriovenous fistula
Localized dilation of the vessel
saccular aneurysm
Thrombosis of the hepatic veins
Budd-Chiari syndrome
Hereditary disorder of connective tissue, bones, muscles, ligaments, and skeletal structures
Marfan syndrome
Permanent dilation of the artery that forms when tensile strength of the arterial wall decreases
true aneurysm
Vessels that have high diastolic component and supply organs that need constant perfusion (i.e., internal carotid artery, hepatic artery, and renal artery)
nonresistive
Flow toward the liver
hepatopetal
Peak systole minus peak diastole divided by peak systole
resistive index
Flow away from the liver
hepatofugal
Vessels that have little or reversed flow in diastole and supply organs that do not need a constand blood supply (i.e., external carotid artery and brachial arteries)
resistive
Increased turbulence is seen within the spectral tracing that indicates flow disturbance
spectral broadening
Sonographer selects the exact site to record Doppler signals and sets the sample volume (gate) at this site
Doppler sample volume
The root of the aorta arises from the left __________ outflow tract in the heart.
left ventricular
The __________ passes anterior to the third part of the duodenum and posterior to the neck of the pancreas, where it joins the splenic vein to form the main portal vein.
SMV
The __________ supplies the gallbladder via the cystic artery and the liver.
right hepatic artery
The aorta continues to flow in the __________ cavity anterior and slightly __________ of the vertebral column.
retroperitoneal, left
The __________ trunk is the first anterior branch of the aorta, arising 1 to 2 cm inferior to the diaphragm.
celiac
The __________ flows from the kidney posterior to the superior mesenteric artery and anterior to the aorta to enter the lateral wall of the inferior vena cava.
left renal vein
The diameter of the abdominal aorta measures approximately __________ cm, tapering to __________ cm after it proceeds inferiorly to the bifurcation into the iliac arteries.
2-3, 1-1.5
The __________ is the second anterior branch, arising approximately 2 cm from the celiac trunk.
SMA
Portal veins become __________ as they progress into the liver from the porta hepatis.
smaller
The __________ courses from the aorta posterior to the inferior vena cava and anterior to the vertebral column in a posterior and slightly caudal direction to enter the hilum of the kidney.
right renal artery
The __________ courses along the upper border of the head of the pancreas, behind the posterior layer of the peritoneal bursa, to the upper margin of the superior part of the duodenum, which forms the lower boundary of the epiploic foramen.
gastroduodenal artery
Three arterial branches arise from the superior border of the aortic arch to supply the head, neck, and upper extremities: the __________, __________, and __________.
brachiocephalic, left common carotid, left subclavian arteries
The __________ is formed posterior to the pancreas by the union of the superior mesenteric vein and splenic veins at the level of L2.
portal vein
The __________ artery takes a somewhat tortuous course horizontally to the left as it forms the superior border of the pancreas.
splenic
The portion of the femoral artery posterior to the knee is the __________.
popliteal artery
The __________ originate in the liver and drain into the inferior vena cava at the level of the diaphragm.
hepatic veins
List the five sections into which the aorta is divided.
root of the aorta ascending aorta descending aorta abdominal aorta bifurcation of the aorta into iliac arteries
Describe the specific differences between arteries and veins.
Arteries are hollow elastic tubes that carry blood away from the heart. They are enclosed within a sheath that includes a vein and a nerve. The smaller arteries contain less elastic tissue and more smooth muscle than the larger arteries. Veins are hollow, collapsible tubes with a diminished tunica media that carry the blood toward the heart. Veins have a larger total diameter than the arteries, and they move blood more slowly.
List the four branches of the aorta that supply other visceral organs and the mesentery.
celiac trunk
superior mesenteric artery
inferior mesenteric artery
renal arteries
Describe the function of the circulatory system.
transport gases, nutrient materials, and other important substances to the tissues and subsequently transport waste products from the cells to appropriate sites for excretion
List the characteristics of a vein.
The veins contain special valves that prevent backflow and permit blood to only flow in one direction–toward the heart. Numerous valves are found within the extremities, especially lower, because flow must work against gravity. Venous return is also aided by muscle contraction, overflow from capillary beds, gravity, and suction from negative thoracic pressure.
Describe how blood is transported from the artery and returned by the veins.
Blood is transported away from the heart by arteries and back to the heart by veins. Arteries divide into progressively smaller branches (smallest = arterioles). These lead to capillaries, where exchange of materials where blood and tissue fluids take place. It is then collected in small veins or venules. These unite to form larger vessels that return the blood to the heart for recirculation.
Define capillaries and describe their function.
They are minute, hair-sized vessels connecting the arterial and venous system. Their walls have only 1 layer. Cells and tissues of the body receive their nutrients from fluids passing through capillary walls. Waste products from cells pass into capillaries. Arteries do not always end in capillary beds; some end in anastomoses.
Describe how Doppler is used to distinguish the presence or absence of flow in a vessel form nonvascular structures.
Bile duct vs. hepatic artery: look for absence of flow in duct
hepatic vs. splenic artery: direction of flow
aneurysm vs. pancreatic pseudocyst: slow flow in aneurysm
Dilated intrahepatic bile ducts vs. prominent hepatic artery: absence of flow in bile duct
A flow disturbance (increased velocity or obstruction of flow) may result from the formation of an atheroma, AV fistula, __________, or aneurysmal dilation.
pseudoaneurysm
Describe the technique that should be used to image the inferior vena cava.
The patient should be instructed to hold his/her breath, causing a slight Valsalva maneuver toward the end of inspiration, dilaating the IVC. The diameter of the IVC may expand 3-4 cm with this maneuver.
Nonresistive vessels have a high __________ component and supply organs that need constant perfusion, such as the internal carotid artery, the hepatic artery, and the renal artery.
diastolic
Resistive vessels have very little or even reversed flow in diastole and supply organs that do not need a constant blood supply, such as the __________ carotid and the iliac and brachial arteries.
external
Explain how to differentiate the inferior vena cava from the aorta.
The pulsatile aorta is easily differentiated from the IVC because the IVC travels in a horizontal course with its proximal portion curving slightly anterior as it pierces the diaphragm to empty into the right arterial cavity. The aorta follows the curvature of the spine, with its distal portion lying more posterior, before bifurcating into the iliac veins.
__________ is a pattern of blood flow, typically seen in large arteries, in which most cells are moving at the same velocity across the entire diameter of the vessel. In other vessels the different velocities are the result of friction between the cells and arterial walls.
plug flow
Doppler only records accurate velocity patterns when the beam is __________ to the flow.
parallel
The flow pattern of the proximal abdominal aorta above the renal arteries shows a high __________ peak and a relatively low __________ component.
systolic, diastolic
The main renal artery has a(n) __________ impedance (nonresistive) pattern with significant diastolic flow–usually 30% to 50% of peak systole.
low
During rejection, the vascular impedance __________, resulting in a decrease or even reversal of the diastolic flow.
increases
The portal vein shows a relatively __________ flow at low velocities, which may vary slightly with respirations.
continuous
Cavernous transformation of the portal vein demonstrates __________ collateral channels in patients with chronic portal vein obstruction.
periportal
With a recanalized __________ vein, the main portal vein and the left portal vein show normal flow, but the flow in the right portal vein is reversed.
umbilical
Describe the effect of gain settings when performing an abdominal aortic ultrasound.
A low-medium gain should be used to demonstrate the walls of the aorta without “noisy” artifactual echoes. These weak echoes may result from increased gain reverberation from the anterior abdominal wall fat or musculature or poor lateral resolution. These factors result in echoes being recorded at the same level as those from soft tissues that surround the vessel lumen, particularly if the vessels are smaller in diameter than the transducer.
The most common causes of aneurysms are __________ and __________.
arteriosclerosis, artherosclerosis
The large aneurysm may rupture into the pritoneal cavity or retroperitoneum, causing __________ and a drop in __________.
intense back pain, hematocrit
The normal measurement for an adult abdominal aorta is less than 3cm, measuring from __________ to __________ walls.
outer, outer
Thrombus usually occurs along the __________ or __________ wall.
anterior, anterolateral
A(n) __________ is a pulsatile hematoma that results from the leakage of blood into the soft tissue abutting the punctured artery, with subsequent fibrous encapsulation and failure of the vessel wall defect to heal.
pseudoaneurysm
What are the clinical findings in a patient with a dissecting aneurysm.
Typical: 40-60 hypertensive males; aneurysm and sudden excruciating chest pain radiating to the back; shock; slow-leak = same symptoms but stable
Describe the three locations where a dissection of the aorta may occur.
Type I: root of aorta and may extend the entire length of the arch, descending to the aorta and into the abdominal aorta
Type II: stretching in all arterial walls, especially in the aorta, resulting in dilation and weakened walls
Type III: lower end of descending aorta and extends into abdominal aorta
Describe other pseudopulsatile abdominal masses that may simulate an aortic aneurysm.
Other Masses: retroperitoneal tumors, fibroid uterus, and para-aortic nodes.
Because the mass is adjacent to the aorta, pulsations are transmitted from aorta to the mass. After an abdominal aneurysm, the most common cause for pulsatile abdominal mass is enlarged retroperitoneal lymph nodes.
In patients with right ventricular failure, the inferior vena cava does not collapse with __________.
expiration
Describe the complications of inferior vena caval thrombosis.
Complete thrombosis of the IVC is life threatening. Patients present with leg edema, low back pain, pelvic pain, gastrointestinal complaints, and renal and liver abnormalities.
The most common origin of pulmonary emboli is venous thrombosis from the __________ extremities.
lower
An elderly male presents with a pulsatile abdominal mass. What does this longitudinal image of the abdomen demonstrate?
large abdominal aortic aneurysm with thrombus along the anterior and posterior borders; lumen of vessel is anechoic
How can the sonographer determine that the inferior vena cava is dilated?
If the IVC measures greater than 2cm and does not show collapse with expiration, it is enlarged.
What abnormality is demonstrated in this image?
thrombus in the IVC
