VI Flashcards
compare the pressure of blood moving through arteries vs veins
- why is this important
arteries - higher pressure, blood propelled through vessels
veins - lower pressure, blood must be pushed back toward heart
veins with less pressure are likely to back up and cause venous insufficiency
differences in vein vs artery structure
veins are
- thinner
- have less smooth muscle
- less connective tissue support
- lack of compliance with increased pressure
what is a capacitance vessel? what is the significance of that?
storage vessels holding 75% of blood volume
when SNS stimulates veins, blood rushes back to heart and decreases peripheral pressure
what causes venous insufficiency structurally
valves lose their ability to prevent retrograde flow and back up occurs
- can be paired with dilation and cause tortuous flow of blood
types of veins
deep
perforating
superficial
deep vein examples and significance
femoral, popliteal, tibial
carry 80-90% of blood back to heart
role of perforating veins
connect deep and superficial veins
job of superficial veins
drain skin / subcutaneous tissue
collect from the dermis
temperature regulation
where are superficial veins and what are some examples of them?
above the deep fascia
greater and lesser saphenous
cut off for venous HTN
> 90mmHg
what plays a major role in venous return? what are methods to overcome it
gravity
respiratory and calf pump
explain the respiratory pump
diaphragm contraction of a deep breath allows for the thoracic cage pressure to decrease
with the decrease, the pressure within veins and lymphatic vessels becomes higher than the thoracic cage
blood and lymph flows to the thoracic cage in response
what can cause venous HTN
degradation of valves
what causes venous insufficiency
vein dysfunction
calf muscle pump failure
- combination of both
what vein is associated with the calf pump
greater saphenous
- incompetence of this vein occurs in 25-50% of all VI ulcers
spider veins is also called
telangiectasia
conditions predictive of VI ulcer? where are each found
spider veins - superficial
tortuous varicose - deep
what is the fibrin cuff theory
as a thin vein stretches over time:
fibrinogen and large proteins move into the interstitial space
once there, they firm up and create a band around the vessel like a tourniquet
what is the white blood cell trapping theory
when blood becomes stagnant, WBC factors begin the inflammation process behind valves when trapped
vein dysfunction causes
venous hypertension and is associated with superficial and perforating veins
what causes vein valve damage
thrombus / blood clot
distended vessel diameter
varicose veins
what causes calf muscle pump failure
calf weakness/paralysis
decreased dorsiflexion
prolonged standing
incompetent valves
edema can result in
local tissue hypoxia
what is one of the biggest predictors of VI ulceration? sequalae associated?
previous VI ulceration
81% recurrence rate
local tissue hypoxia / malnutrition
scar tissue induced skin breakdown
risk factors of VI ulcer
calf muscle pump failure
trauma (edema)
previous VI ulcer
> age
obesity
diabetes
diabetes risk factors for VI ulcer
increased risk of microvascular disease and impaired immune response
impaired wound healing (hyperglycemia contraindicates healing)
what is the gold standard for examining veins? any other alternatives?
venogram - expensive and invasive
Ultrasound instead
- noninvasive, 95% sensitive and specific
difference in significance of proximal vs distal DVT
distal DVT - <20% of them embolize
proximal DVT - 50% of them embolize
compression contraindication score on ABI
<0.5
what is the Trendelenburg Test
supine with leg at 45° elevation for a minute
- look for venous distension
significant times associated with trendelenburg test? what is indicated by each?
time to venous distension:
with tourniquet - <20 sec
–> deep / perforating vein
without - <10 sec
–> superficial vein
what to identify during Doppler Ultrasound
presence/absence of sound
intensity of sound
lack of spontaneous sounds
what is the reflux test?
using a doppler
- squeeze proximal to doppler, if a sound is detected then back flow is indicated
how are VI ulcers classified
depth
etiology
CEAP
what is CEAP?
clinical etiology anatomy and physiology classification
CEAP scores
C0 - asymptomatic
C1 - spider veins <3mm
C2 - varicose veins >/=3mm
C3 - leg edema
C4 - skin and subcutaneous changes
C4a - hemosiderin
C4b - lipodermatosclerosis
C5 - healed venous ulcer
C6 - current venous ulcer
CS - symptomatic
what is the significance of a C1-2 or 3 progression
C1 to 2 = into larger veins, more torturous
C2 to 3 = higher pressure in venous column
some symptoms associated with C4b classification
lipodermatosclerosis
- fibrin and proteins into interstitium
- dry / crusty skin
- champagne leg
symptoms associated with CS
leg achiness
heaviness
tightness
pain due to venous dysfunction
Etiology criteria of CEAP
Ec - congenital
Ep - primary
Es - secondary (other DVT)
anatomy criteria of CEAP
As - superficial
Ad - deep
Ap - perforating
pathophysiology of CEAP criteria
Pr - reflux
Po - obstruction
5PT method includes
Pain
Position
Presentation
Periwound
Pulses
Temperature
difference in pain between VI and AI
V - mild to moderate, decrease with elevation or compression
A - severe, increased with elevation
difference in positioning between VI and AI
V - medial malleolus, medial lower leg, area of truama
A - distal toes, dorsal foot, area of trauma
difference in wound presentation between VI and AI
V - irregular shape, red/ruddy wound bed, fibrous yellow or glossy coating, copious drainage
A - regular shape, pale granulation tissue, black eschar/gangrene, dry
difference in periwound and extrinsic tissue between VI and AI
V - edema, cellulitis/dermatitis, hemosiderin deposition, lipodermatosclerosis
A - shiny/dry skin, loss of hair growth, thickened yellow nails, pale/dusky/cyanotic
difference in pulses between VI and AI
V - normal or decreased due to edema
A - decreased or absent
difference in temperature between VI and AI
V - normal to mild warmth
A - decresed
healing time for full-thickness venous ulcers
avg - 8 weeks
smaller - 5 to 7
larger - 10 to 16
cut off time in healing of VI ulcer
> 4 weeks without any healing –> refer
define full-thickness venous ulcer
through epi and dermis, but not through hypo
precautions of VI procedural interventions
concamitant arterial disease
allergic reaction/sensitivity
inappropriate whirlpool use
why may using a whirlpool not be the best treatment of VI ulcer
warm water will cause vasodilation, greater likelihood of edema
gravity will allow for edema and pulmonary HTN to occur
increased moisture on the wound will not help an already wet wound
when to refer if assessing a VI
> 3 on DVT criteria
failure to progress
wound culture/infection
bone or capsule exposure
local wound care technique
protect periwound skin
address wound bed
enhance venous return
patient/caregiver education
contraindications of compression therapy
ABI <0.7
acute infection
pulmonary edema
congestive heart failure
DVT
difference between short and long stretch compression bandages
short = higher working pressure, lower resting pressure
long = lower working pressure, higher resting pressure
what patient ability would a paste bandage be indicated for
ability to ambulate
- nonelastic compression
laplace’s law
enough pressure to reduce edema without causing ischemia
layers and their roles of short-stretch compression bandages
inner = absorb excess drainage, padding
middle = drainage
outer = increased compression
therapeutic exercises to be used
range of motion and strengthening
- focus on ankle plantarflexors
aerobic exercise
gait and mobility training
gold standard for assessing DVT
venogram
what do doppler ultrasounds test
venous flow
vascular volume
valve competency
