108 Flashcards
Deep system consists of:
- IVC: connects CIV to rt atrium
- CIV: internal and external iliac veins
- IIV: drains blood from pelvis aka hypogastric vein
- EIV: extends to inguinal ligament
- CFV: inguinal ligament to bifurcation
- FV P,M,D, and PFV
- Pop V: runs behind knee, connects anterior tibial vein
- ATV: drains anterior calf and foot, paired veins
- PTVS: drains medial and posterior calf and foot
- PER VS: drain medial and posterior calf
Superficial system consists of :
GSV and SSV
why would we see pulsatility in CFV or POP V?
increased resistance due to CHF causes pulsatility
What are the three systems in the leg for a pump?
- Foot pump: primes the calf pump
- Calf veno motor pump: major ejection
3: thigh pump: ejects thigh blood volume
What is venous thromboembolism?
Generic term for saying there is a clot in the venous system (superficial, deep, or even PE in lungs)
Phlegmasia cerulean dolens
what is it? why does it happen? what do we see?
- has a high predictive positive value (PPV) for DVT
- Iliofemoral outflow obstruction presents as massive thigh/calf swelling. blood is trapped so calf swells up
- pt is in pain, and leg looks purple
Superficial thrombophlebitis
Not life-threatening unless thrombus extends into deep system, but its more painful than DVT
Symptoms include:
erythema/ inflammation
tenderness
palpable cord or mass(might be able to feel blood clot)
Acute DVT
- happened during a short period of time
- weakly echogenic or partially anechoic thrombus (heterogeneous)
- poorly attached thrombus, spongy texture and dilated vein
- we can get acute DVT if we have a chronic DVT
Chronic DVT
- highly echogenic thrombus (hyperechoic)
- well attached thrombus
- rigid/fibrous texture
- vein smaller than artery
- recannalization and or venous webbing (blood is beating down on door of clot so little webs are created to get blood moving again
May Thurner Syndrome
what is it? why does it happen? what do we see?
- thrombosis of left iliac vein
- caused by compression of the overlying right iliac artery
- leg is swelling, color change, erythema and warmth
What must you compare before ruling out iliac obstruction?
must compare bilateral CFV waveforms to rule out iliac obstruction
A) You’re scanning bilateral CFV’s, Lt CFV is a flat line, while Rt CFV shows phasic flow. Where is the clot located?
B) If both waveforms are flat, where is the clot?
A) Clot is in the left CVF
B) Clot is either in both CFV and the IVC, or just IVC
a) Having a flat line on venous flow means …
b) Having pulsatile flow in venous flow means…
a) we have a clot
b) we have cardiac influence, could be CHF
Spontaneity is
flow within the vein occurs on its own
Phasicity is
flow ceases with inspiration, resumes with expiration
Augmentation is when
flow increases towards heart when vein is compressed distal to the site
Valsalva maneuver
pushing down on pt belly and flow stops
Symptoms for UVE
- pain and swelling in arm
- local erythema, palpable cord
- dilated superficial veins of arm/shoulder
- chest pain, SOB (if PE)
Deep veins of upper extremity
- SVC (drains blood from arms to rt atrium)
- Innominate (joins to form SVC)
- Subclavian (runs above clavicle from innominate to axillary)
- Axillary (begins at lateral margin of first rib)
- Brachial (usually paired axillary vein to elbow)
- ulnar (brachial wrist to pinky side) and radial (brachial wrist to thumb side)
Superficial veins in UE
- basilic (joins brachial v to from axillary {travels medial side)
- Cephalic (from axillary v travels down lateral arm{outer side of arm)
- Median cubital: connects cephalic and basilica at elbow
- What is the subclavian vein assessment?
- contralateral assessment?
- Subclavian vein cannot be compressed due to clavicle but we can do sniff test (only if you have reason to) and we must use color and doppler
- its important and required by ICAVL that a comparison be made with the contralateral subclavian vein in the same spot
Pulsatility is
related to cardiac nature, arterial waveforms
What do you do to look for thrombosis on the upper peripheral veins?
b) what do you do to look for thrombosis in the upper central veins such as clavicle?
a) use compression
b) use grayscale, color and doppler
Paget-Schroetter
(what is it? how does it happen? what do we see?0
- Spontaneous thrombosis of subclavian or axillary vein
- repeated extrinsic compression of subclavian and axillary vein can lead to this (Sylvester Stallone)
- veins pop out, looks like Swiss cheese on US
Superior vena cava syndrome (what is it? how does it happen? what do we see?)
- Occlusion or compression of SVC, increasing venous pressure
- Clot in SVC, blood won’t be able to get to heart so it creates buildup and increases venous pressure
- Edema of neck face and arms usually bilaterally
LEA symptoms (6)
- no limb swelling
- intermittent pain when walking
- foot/limb coolness and pallor
- rest pain
- gangrene, tissue necrosis
What is reflux?
Abnormal reversed flow direction
What is tumescence in venous ablation?
Injecting saline and lidocaine to cause local swelling around vein to be “cooked”; acts as heat absorber and prevents burns to underside of skin
What is an in situ vein bypass?
GSV remains in place, valves are excised with a valvulatome, perforating veins and tributaries are ligated and cut, and prox GSV is cut and sewn into CFA
What factors govern (control) arterial flow?
- cardiac output
- intraluminal wall resistance
- arterial wall compliance
A person who is at rest that has arterial occlusive disease…
do not have a lot of blood getting down to capillary bed being in a resting state
What are the 4 indirect physiologic testing (blind testing)?
- Pressure assessment (ABI/segmental pressures)
- Plethysmography (PVR and PPG)
- Doppler waveform analysis
- Exercise stress testing
Pros and Cons of using PPG in segmental pressures
pros:
convenient, requires less skill, bilateral capability
cons: ambient light interference, no audible pulse, not good for severe disease
What is considered normal ABI?
0.9-1.3
>1.3= likely calcified
<0.9= abnormal
<0.8= probably claudication (pt is limping)
<0.5= multilevel disease(more than 1 cuff seperated) or long segmental occlusion (2 or more cuffs back to back)
<0.3=ischemic rest pain (pt needs to rest legs off of bed when at rest)
What is considered in flow disease?
Aorta to iliac arteries
What is considered normal TBI (toe brachial index)?
Normal = >0.75
abnormal= <0.66
in between is inconclusive
When do you see calcified arteries show up in indirect testing?
- In diabetic pt
- chronic steroid therapy
- renal dialysis pt
In presence of calcified arteries, what methods must you use instead of segmental pressures?
PVR, CW doppler or even toe pressures (toe pressures will probably be inaccurate)
Who do we exercise for stress testing?
- patients that complain when walking (intermittent claudication)
- ABI is 0.85-0.4
- if resting study is normal but pt has pain when walking
If pt has symptoms occur only at rest and the resting study. is normal, do we exercise the pt?
No bc that is rest pain
What are the contraindications for treadmill exercise?
- questionably cardiac status
- resting ischemia (ABI <0.3)
- ischemic ulceration
- poor ambulatory
- normal resting study with resting symptoms but no claudication
What diameter must the GSV be to have a high graft patency rate?
Greater than or equal to 2.5mm. less than 2.5mm will have high failure rate
NOTE: >2mm is too small (unsuitable) and must evaluate contralateral GSV (opposite leg)
What is the bypass graft evaluation consist of
- identify graft type and location
- perform ABI
- Use color and spectral to evaluate blood flow
You evaluate the entire graft for:
- stenosis
- wall irregularity
- aneurysms/pseudo
- AV fistulas (in situ only)
- Partially excised valve leaflets
In a 50% graft stenosis what do we have?
PSV is greater than or equal to 150cm/sec and velocity ratio of greater than or equal to 2.0
NOTE: if velocity ratio is >= 3.5 and PSV >300cm/s pt needs intervention to prolong graft latency (its failing)
PSV for in stent restenosis for Superficial femoral artery (SFA)
for 50%-79% and 80%
- 50-79%: PSV >190 and velocity ratio is 1.5
- 80%: PSV>275
What are is a contraindication for UEA?
Do not perform arm pressure measurement in arm with a graft, use PVR assessment or CW doppler
Symptoms of UEA disease?
- arm and or hand weakness
- reduced or absent pulses
- hand numbness/weakness/pain that is positional
- ischemic fingers
- cold sensitivity
For radial artery harvest (CABG) what must you evaluate?
Palmar arch patency
