CHapter 25: Venous Air plethysmography APG Flashcards
Air plethysmography is used for
evaluation of venous function
venous insufficiency
quantitative venous reflux
limitations of APG
will not diagnose incompetent perforators or isolated incompetent distal veins
patient positioning for APG
study started with patient supine
then patient assumes a variety of standing positions
APG principles
measures volume changes
pneumatic cuff connected to pressure transducer
volume changes amplified and converted to analog display
documents volume changes secondary to position changes
how is an APG test set up
pt supine
cuff applied to lower leg
air injected into cuff to 6mmHg
APG systems are
manually calibrated
APG test
leg elevated to empty venous system
pt quickly stands bearing weight on contralateral leg
pt stands with weight distributed equally on both feet
pt performs 1 toe tip exercise
10 toe tip maneuvers then completed
pt supine
leg elevated to empty venous system again
what does the toe tip exercise do
decrease in calf venous volume
venous volume is calculated how
ejection volume (EV) and the venous filling time VFT
if finding is abnormal after the first set of tests
repeat study with tourniquet
Venous filling index show what
rate of venous refilling
venous filling index VFI is calculated how
using venous volume and venous filling time
Normal venous filling time
should be a low number
Ejection fraction (EE) measures
calf muscle pump function
ejection fraction (EE) is calculated using
ejection volume (EV) and functional venous volume (VV)
