Chapter 26: The Inferior Vena Cava and Iliac Veins Flashcards
the union of two or more veins to form a larger vein; the equivalent of a bifurcation in the arterial system
confluence
a typically cone shaped medical device designed to prevent pulmonary embolism; it is placed into the inferior vena cava so that it can trap venous thromboemboli for the lower extremities before they travel to the heart and lungs; the device does not obstruct the flow of blood unless it is completely obstructed with trapped thrombus
inferior vena cava filter
a detached fragment of thrombus, usually from the lower extremity veins, that travels through the inferior vena cava and right heart and lodges in a pulmonary artery
pulmonary embolus
the space between the abdominal cavity and the muscles and bones of the posterior abdominal wall; vascular structures in the retroperitoneum include the inferior vena cava, the iliac veins, and the abdominal aorta
retroperitoneum
partial or complete occlusion of a blood vessel as a result of clot
thrombosis
IVC venous tributaries
hepatic veins
renal veins
common iliac veins
right adrenal vein
right ovarian vein or testicular vein
inferior phrenic vein
four lumbar veins
median sacral vein
distended vein with echogenic material within lumen; absent flow; no signal
occlusive thrombus
echogenic material that appears partially free floating and partially attached to the vessel wall; present or diminished flow; continuous flow; loss of respiratory and cardiac variation
partially occlusive thrombus
intraluminal tumor originating from renal or hepatic veins or extrinsic mass; absent flow; collateral veins may be detected; no signal or continuous signal in partial obstruction; look for arterial flow within tumor
neoplastic obstruction
echogenic metal structs of filter; echogenic material within lumen; absent flow; no signal or continuous signal with partial obstruction
IVC filter with thrombus
Paired IVC or IVC on left side only
left-sided IVC
The IVC drains into _____ or azygos vein with left sided IVC.
left renal vein
intrahepatic IVC not visualized
absent intrahepatic IVC
dilated vein; tissue bruit; pulsatile flow cephalad to fistula
caval fistulas
Iliac vein compression syndrome is also known as:
May-Thurner’s syndrome
Left iliac vein compressed by the right common iliac artery
May-Thurners syndrome
drain lower extremities
external iliac veins
continuation of common femoral veins
external iliac veins
The external iliac veins begin at the ______
inguinal ligament
drain pelvic viscera and musculature
internal iliac veins
The internal iliac veins at level of ______ to form common iliac veins.
sacroiliac joints
The IVC begins at the confluence of _________ at level of 5th lumbar vertebae
right and left common iliac veins
The IVC terminates into the ______
right atrium
conducts venous blood to heart from veins originating in the lower extremities and all organs and tissues inferior to diaphragm
IVC
Mean diameter of IVC at level of renal veins
17- mm
excessively large IVC diameter
mega cava
Patient preparation
fast for 8 hours
diameter of IVC may appear to change with phasic changes in abdominal pressure produced during respiration
quiet respiration
results from propagation of a lower extremity venous thromboembolism represents most common pathologic finding
thrombosis
An IVC filter is typically placed _____
just below level of renal veins
echogenic lines that converge to a point near the level of the renal veins
IVC filter sonographic appearnace
abnormal connections between IVC and surrounding vessels; may occur spontaneously or surgically created
caval fistulas
During quiet respiration, the diaphragm descends, creating _____ pressure in abdomen and _____ pressure in chest
positive
negative
The proximal IVC waveform near the heart is:
pulsatile
Flow in the distal IVC has a ____ waveform
phasic