Vasc (3) test prep

what are venous waveforms affected by?

Respiratory variations, and Right Atrium pressure

how is antegrade and retrograde venous flow displayed?

Below baseline= movement away from transduce (Antegrade Venous Flow)

Above baseline= movement toward transducer (in Red) (Retrograde Venous Flow)

What is spontaneous blood flow ( venous)

Spontaneous Blood Flow

• End resistance of Right Atrium is very low ( 0-5 mmHg)

• Therefore blood flows spontaneous toward Right atrium

– Changes in flow based on respiration

• As diaphragm compresses IVC during Inspiration, Blood flow decreases and can even briefly change direction

for expiration theres less venous return in upper extremities and more in the lower (opposite with inspiration)

normally become less spontaneous as travel distally (Especially common in calf)

• Muscle contraction propels blood flow back towards heart

– Valves maintain antegrade flow

– Calf muscle pumps venous flow during contraction (walking)

Based on these waveforms, explain at what point the patient is breathing in vs out

With expiration theres less venous return in upper extremities and more in the lower, so when we see cessation ( no flow) that means they’re inspiring and when we see flow they’re breathing out.

Why do we compare phasicity of venous waveforms side to side

Since both vessels are equidistant from the heart, the phasicity of the blood flow should be equivalent.

Continuous waveform may be indicative of proximal obstruction ( closer to heart)

Based on this image, Here the Left CFV signal appears much more phasic then the Right. You need to evaluate proximally, so evaluate the REIV, and RCIV for thrombus

what is normal venous compliance

• applying pressure directly top of vein Results in veins walls coapting completely

• Applying pressure distally to where insonating will result in increased antegrade venous flow

• Applying Pressure proximally to where insonating, will stop blood flow just a little bit (will see cessation) and when u release your grip you’ll see retrograde flow again.

what does a echo filled lumen indicate, what precautions should you take.

venous thrombosis, be careful with venous compression because there is a risk of embolization if applying too much pressure.

What is the Valsalva maneuver

( used it PT’s legs are sensitive)

Pt takes a deep breath in and bears down (tightens stomach muscles) increases

intrathoracic pressure

Normal response is no venous flow during Valsalva and augmented antegrade flow when pt releases

– Abnormal is retrograde flow throughout Valsalva

Is this venous valve competant or not? how can you tell.

Proximal compression assesses competence of venous valves

We can tell it competent because competent valve prevent retrograde venous blood flow, and we see w/compression a cessation rather than retrograde flow.

is this waveform abnormal or normal?

this is pulsatile flow which is abnormal, Due to increased Right Atrial Pressure. Indicative of Congestive Heart Failure

Based on this, is this a normal venous blood flow?

No, this is a abnormal continuous venous blood flow. Indicative of proximal obstruction

But this could also be

• Venous thrombosis

• Patient Position or Breathing related

Do not perform Valsalva or Compressions Maneuvers on a patient with Continuous

Venous Waveforms until you rule out proximal venous thrombosis ( risk of embolization)

What are our deep veins, superficial and perforating veins

Deep Veins : CFV, PFV, FV, POP, PTV, PER

– Have Accompany arteries

Superficial Veins: GSV, SSV

– Do not have accompanying arteries

Perforating Veins: name by location (ie. prox calf)

– Connect deep and superficial veins

What are the objjectives for LEV exam,

To detect Venous Thrombosis (DVT/ SVT) and To evaluate for Venous Insufficiency (Reflux )

( you will be told what is needed to be assessed)

What vessels are in the mickey mouse sign

memorize, look at image.

how do you begin your LEV exam

1. start with bilateral CFV, if it’s phasic then we can perform our maneuvers (valsalva, prox compression and dist)

• if its not phasic then investigate iVC and iliacs for prox obstruction with color and spectral doppler only. ( for risk of embolization)

If CFV appears continuous what would you do?

Investigate proximally (IVC, CIV and EIV)

Where does the PFV run, why is it important?

runs medially and posteriorly from the CFV

• At proximal-mid thigh joins proximal popliteal vein

• Profunda serves as important collateral pathway for venous return from calf

if FV is Bifid what would you do?

normal variant in approx. 25 % of patients ( means it’s duplicated)

• Both bifid branches need to be evaluated during exam

What passes through the adductor canal?

Passageway from medial anterior thigh to posterior leg

• bordered by 3 muscles

• Femoral Artery, Femoral Vein and Saphenous Nerve pass through

Based on this image what is being shown? what vessels does it bifuricate into?

the TPT, distal to Anterior Tibial Veins origin

• Bifurcates into four vessels ( PTV and PER)

• PTV is the more anterior set of vessels

• PER is more posterior to PTV, deeper than PTV. Terminates into 2 branches at ankle

Where are the superficial veins located.

Great Saphenous Vein (GSV)

• Medial on thigh and calf

Small Saphenous Vein (SSV)

• Posterior on calf

Both GSV and SSV

In fascial layer: “Cleopatra eye” landmark ( shown in image)

• Have branches

• Have no accompanying arteries

Axial (main ) trunk is located within “Cleopatra eye”

What is the criteria for venous insufficiency ( reflux)

normal valve closure <0.5 sec ( in left image)

Abnormal valve closure >0.5 sec ( in right image)

Blood flow stops flowing in a vein, becomes coagulated (semi-solid or solid state)

• Location of thrombus determines its name

• Age, location and occlusive nature of thrombus important to note ( if it’s newer it’s not as solid)

What is virchows triad

(trauma, stasis, hyper-coagulability) by having these three symptoms will increase their risk for venous thrombosis.

What are critical results

findings which need a physician to see the patient directly after the exam

These typically include:

• >5.0 cm AAA or >2.5 cm CIA or EIA aneurysm

• 80-99% ICA stenosis

• Acute DVT

• ABI below 0.3 with Acute Arterial Occlusion

REMEMBER: don’t give critical results to patients state something like this “ I want to make sure we have everything for the doctor, I’ll be right back”

What is a critical venous thrombus finding

Acute DVT

An Acute SVT that is:

• Extensive (bilateral full length of GSV)

• Near junction with deep vein (measure distance)

If you can’t get ahold of reading physician to report critical finding what would you do?

recall in 5 mins, if still no answer, contact your direct supervisor and transport patient to ED ( emergency department)

• Essential to not send a patient home with critical results

How do you determine DVT from SVT

Deep veins are near bones and typically have adjacent arteries, superficial veins are within fascial layer and do not have accompanying arteries

•Remember to look for anatomical variants

• Bifid Femoral veins

• Hypoplastic veins (smaller or not well developed veins) Does not mean they are superficial just because they appear small.

When do varicose veins develop, how do they appear?

When superficial venous valves are incompetent. Incompetent valves allow retrograde blood flow (reflux)

– Retrograde flow leads to venous hypertension in distal vein segments

– Varicose veins can occur in Deep veins, but this happens less often and they typically do not show superficially

• Veins with reflux appear ropy, protruding, and tortuous

• Can be painful and cause swelling

• Most commonly found in lower extremities

Whats the difference between competant and incompetant venous valves

Competent valves: 90mmHg in veins while standing to 20-30

mmHg while walking ( from a competent venous pump)

Incompetent Valves: Lead to persistent increased venous pressure

in calf veins due to retrograde blood flow (toward the foot)

• Results in soft tissue edema, skin thickening, hyperpigmentation and skin ulceration

Where is venous insufficiency more likely to occur? What veins are affected with venous ulceration?

More likely to occur in superficial veins than in deep veins

• If in deep veins, likely associated with chronic DVT. Will less likely appear superficially like when superficial veins are affected

– Symptoms: swelling, aching, pain

• Patients with venous ulceration following DVT, often have both deep and superficial venous reflux present

What is the venous disease progression

Veins visibly bulging

Leg swelling

Skin Discoloration

Ulcerations

Nonhealing ulcerations

( only gets to non healing ulcerations if no prevention is done)

What is the Clinical C classification ( for venous insufficiency) CEAP Classification ( only C category)

( shown in image)

C0: No clinical signs

C1: small varicose veins

C2: large varicose veins

C3: Edema

C4: skin changes without ulceration

C5: skin changes with healed ulceration

C6: skin changes with active ulceration.

What is clinical presentation for venous insufficiency

Patients often have pain, edema, dilated visible veins, skin changes near ankle, swelling in extremity, or a feeling of heaviness or aching with prolonged standing.

• Note that some patients may describe venous claudication- severe

cramping and burning pain with walking

• Often associated with hypertension in both deep and superficial

venous systems and obstruction of iliofemoral vein in cases of poor

collateral pathways

• Recall that hydrostatic pressure (typically 90mmHg) in the lower

extremities will not be alleviated as well with insufficiency even with calf pump assistance

How does PPG test for Reflux, Whats the criteria?

Can use PPG probes to determine venous refill time (VRT)

• PPG is a measure of volume of blood flow in tissue (Less commonly used)

Place probe on distal GSV at medial malleolus and have patient perform dorsi flexion

Amount of time for veins to refill recorded ( image of a normal refill time is shown on term, abnormal is shown on definition card)

• Venous Refill Time Criteria:

– Normal >40 seconds

– Borderline 20-40 seconds

– Abnormal <20 seconds

What is LEV Insufficiency Exam Patient History Assessment

Risk Factors for DVT

• LE Trauma

• History venous ulcers or varicosities

• History vein surgeries or venous interventions

– Venous ablation

– Venous stripping

– Vein harvesting

– Iliac vein stenting (History of May Thurner’s Syndrome)

• Family history of venous thrombosis

• Congestive Heart Failure (CHF)

What Instrumentation would you use for a LEV Insufficiency Exam

Usually use a 5-7 MHz linear transducer

• May change depending on vein location for better visualization

More superficial veins may require higher frequency

Deeper veins may require lower frequency

• Rapid cuff inflator may be used instead of manual distal augmentation

• Standardizes the compression of distal augment with predetermined

cuff size and mmHg over specified time

– May be ergonomically helpful, however only useful in thigh (for calf

measurements still need to distally augment)

• Not all labs will have this device

What is Patient Positioning for LEV Insufficiency

supine portion

• Reverse Trendelenburg (patient lies on back with head higher than the lower limbs. Head elevated 20 degrees)

• Leg externally rotated

• For better visualization can use Prone position for

» POP Vein

» Prox PER and Prox PTV

» Soleal veins

» SSV

Dependent position (leg hanging off bed) ( to dilate calf veins (PTV and PER))

standing portion

• Leg externally rotated

• Care taken patient keeps weight on leg not being evaluated

– Allows for distal augmentations to be easier

What is protocol for second part of exam, (standing or in upright

position)

Bilaterally: Obtain 5 images:

• Venous Compression

• Color Doppler with distal Augment

• Spectral Waveform with Valsalva / proximal compression and

• Spectral Waveform with Distal Augment

• AP and width transverse measurments

– At the each of the following

• SFJ (sapheno-femoral junction)

• GSV thigh prox, mid and distal

• GSV knee

• GSV calf prox, mid and distal

• SPJ (sapheno-popliteal junction)

• SSV prox, mid and distal

• GIAC

What is the protocol for the First part of exam, complete LEV for Thrombus

• Bilaterally:

– Venous compressions from hip to ankle

– Obtain 4 images:

• Venous Compression

• Color Doppler with distal Augment

• Spectral Waveform with Valsalva / proximal compression and

• Spectral Waveform with Distal Augment

– At each of the following

• CFV

• PFV

• FV prox, mid and distal

• POP prox mid and distal

• PTV prox, mid and distal

• PER prox, mid and distal

• GSV thigh, knee and calf

• SSV calf

What is the protocol modification for venous insufficiency

While in Reverse Trendlenburg

– Assessment of deep veins for DVT and reflux :

• Bilateral CFV, FV, POP, PTV and PER

• Remember bilateral CFV part of every unilateral LEV

– Evaluate superficial veins for SVT and reflux:

• SFJ, GSV origin, prox thigh, mid thigh, distal thigh, kneed, prox calf, mid

calf, distal calf

• SPJ, SSV origin, prox calf, mid calf , distal calf

What would you do if the GSV and SSV are positive or negative for reflux?

if GSV and SSV positive for reflux in Reverse Trendelenburg position, then exam complete ( no need to go beyond this)

IF GSV or SSV negative for reflux in Reverse Trendelenburg,

then patient does standing portion, reassess junctions and or area of visible varicose veins for reflux

What are the two types of varicose veins

Primary: Direct or congenital failure of venous valves ( EX: injury)

Secondary: Failure of venous valves due to acquired condition

• EX: DVT, Pregnancy, Klippel-Trenaunay Weber (KTW) Syndrome

What are varicose vein symptoms

Visible bulging veins

• Heaviness in lower extremities

• Itchy

• With progression of reflux: you’ll see Skin discoloration and Venous stasis ulcerations

Where do most varicose veins (VV) originate

saphenous veins or saphenous branches

• Important to note valvular competency of

saphenous branches

GSV: Anterior lateral accessory saphenous and Posterior medial accessory saphenous

SSV: Giacomini

Posterior calf VV= SSV reflux

Medial thigh VV = GSV reflux

Medial calf vv GSV reflux (may also be calf perforator)

Anterior lateral thigh VV = AL Acc of GSV reflux

Posterior medial prox thigh vv= PM Accessory of GSV reflux

Posterior thigh vv= Giacomini reflux

For venous insufficiency what valve closure time is considered pathologic

Greater than 0.5 sec is considered pathologic

• Remember refluxing veins typically are larger than veins with competent valve

When documenting venous reflux what is important to add

• specify specific location ( this determines intervention)

• Finding source of reflux is important to treatment

  • Junction, perforators, etc

• Finding termination of reflux is important to treatment

  – Multiple thigh vv, perforator, etc

What is KTW syndrome

Rare congenital condition

• Malformation of veins and lymph nodes

• Commonly presents with deep venous anatomy variations

– Ex: Hypertrophic Femoral vein with significant collaterals ( FV looks thick)

Patient may have: Port wine stains, Soft tissue Hypertrophy, AVMS (arteriovenous malformations), Varicose Veins, Variations in venous anatomy, Extra veins or absent veins

( port wine stain shown in image)

What is Venous Insufficiency Treatment

Limb Elevation: ( Legs elevated above heart after periods of prolonged standing or sitting)

Compression Therapy: ( Unna Boots and Compression Stockings

• Ask for RN assistance to remove Unna Boot prior to exam

– Patients frequently have ulceration under boot, Boot is meant to help heal the ulcer, Boot will need to be cut off to remove

Sclerotherapy: sclerosis= hardening of tissue, hardens vein walls to close it

• In office procedure, Injection of foam solution into vein to sclerose

• needle injection or catheter. Can be ultrasound guided or vein light guided

• Often treatment of choice for small veins (EX: reticular or spider veins and sometimes for perforators)

Ablation- Laser, RFA (Radiofrequency Ablation): Patient is awake, often no sedation given. Catheter based. Heat is applied directly inside refluxing superficial vein to close it.

• Either uses radiofrequency (RF) or laser energy to create the heat needed for the ablation. Sonographer ensures tip of catheter is approx. 2 cm away from deep vein in Sagittal view.

Surgery- Ligation: performed in the OR with patient under general

anesthesia. Refluxing superficial vein is cut at the junction and knee

and any branches are tied off.

Ablation procedure will leave vein and branches in place, while ligation

and stripping will remove it entirely

What is Phlebectomy, what is it used for

Can be done after ablation if there are remaining varicose veins that cause lingering symptoms, especially for the bulging superficial VV (Cosmetic reasons)

What is LE Vein mapping

The evaluation of a vessel course (pathway), patency (including wall condition) and diameter

• Mapping is usually a pre-surgical procedure to determine suitability of vessel for use as a bypass graft conduit, dialysis access fistula, or CABG

How do you determine if a vein is adequate for use as an arterial bypass graft?

To serve as bypass graft, vein needs to be large and patent. Too small a vein will not sustain arterial graft blood flow

• Areas of decreased size create stenosis within graft

Occlusive or partially occlusive thrombus within vein will obstruct arterial graft blood flow

What is LEV Patient Positioning for vein mapping

Supine with leg rotated outwardly

– If needed for POP, PTV, PER or SSV you can use prone position

• Reverse Trendelenburg

• you need Warm room with limbs covered until imaging

( usually use a Linear 5- MHz transducer High frequency transducer may be needed for more superficial veins)

What is the LEV Mapping Protocol

• Venous compressions and Spectral waveforms with distal augment and Valsalva or proximal compression of the following

– CFV

– SFJ

– FV prox, mid and distal

– Popliteal vein

– PTV, PER

• Remember all LE venous exams (including unilateral) require bilateral CFV images

Then AP and Width diameter measurements of

– GSV origin

– GSV thigh (prox, mid, and distal)

– GSV knee

– GSV calf (prox, mid, and distal)

– SSV origin, prox, mid, and distal

What is the order of the LEV vein Preferred for LEA bypass ( In order of most preferred to least)

1. Same leg as bypass

• Typically GSV preferred over SSV (GSV is larger)

– Contralateral leg to planned bypass

– Arm vein

– Synthetic

When are tourniquets used

used for upper extremity vein mapping, Tourniquets are not used for Lower Extremity Vein mapping

What is the LEV mapping criteria

0.35 cm is considered adequate size of a vein for use as an arterial bypass graft

• to small will cause graft failure, so most important to note any areas that appear < 0.35 cm

what is patient positioning for UEV

Supine with head turned away from side examining for access to IJV and Subclavian vein

• Extend arm down bed or can use a pillow to support patient across lap if needed

For mapping want veins as large as possible:

– Limb in Dependent position ( below level of body)

– Warm patient- use blanket to cover limb prior to exam

– Tourniquet typically used on upper extremity

For UEV mapping how do you place a tourniquet

placed at upper arm, near axilla

• Tourniquet should be tightly placed around arm

• Avoid tying tourniquet into a knot, as gel will make untying difficult

CANT use a tourniquet on a patient with a history of ipsilateral mastectomy or lympadenectomy

How does the UEV mapping protocol change for Bypass or dialysis access

if mapping for peripheral vascular bypass or coronary artery bypass= only need to assess veins

If mapping for dialysis access= need to assess both arteries and veins

Regardless if the exam if unilateral or bilateral for UEV what do you always need to scan bilaterally

bilateral B-mode, Color Doppler and Spectral Doppler images of Subclavian veins are needed ( RT and LT)

How do you mark for UEV mapping

Best way to mark is use center of transducer as a guide

– Locate vessel in transverse

– Place vessel in center of image

– Make small dot with sharpie in center of transducer

• Straw occasionally helpful if sharpie unable to mark through gel, straw

makes indent while remove gel to place sharpie mark

– Connect dots to draw course of vessel

What is the UEV mapping protocol for UEV DVT assessment and UEV superficial vein mapping.

UEV DVT assessment

• B-mode, Color Doppler and Spectral waveforms of IJV, Innominate and Subclavian,

• Transverse compressions, Color Doppler and Spectral waveforms with distal

augmentation Brachial, Radial and Ulnar

UEV superficial vein mapping

• Transverse compressions and distal augmentation

• Cephalic vein

– Upper arm: proximal, mid and distal

– Elbow

– Lower Arm: proximal, mid and distal

• Basilic vein

– Upper arm: proximal, mid and distal

– Elbow

– Lower Arm: proximal, mid and distal

What is the criteria for UEV mapping, what would you do if the basilic and cephalic appear inadequate

Vein is considered adequate if

• Appears patent with no wall damage, No evidence of thrombosis or wall thickening

• Diameter greater than 0.4 cm for arterial bypass graft or 0.25 for dialysis

access

If both basilic and cephalic appear inadequate modify protocol with

addition to assess brachial veins

• Remember median cubital vein can connect upper arm cephalic

and upper arm basilic to form longer segment if needed

– Typically mapping upper extremity for bypass graft if lower extremity

veins were not adequate as typically bypass will be planned for lower

extremity

What is the cephalic vein a common location for, where does it originate and run

Originates from subclavian vein posterior to the clavicle

– Important to document cephalic arch diameter

• Common location for stenosis in dialysis access fistulas

Vein typically courses anterior along deltoid and anterior to

bicep muscle

– Be sure to note any deviation from common course on preliminary

report

How can you identify and scan the cephalic vein during an ultrasound exam

Use the thumb as a landmark—vein runs along the lateral portion of the arm

Look in the antecubital space to locate and follow it laterally

Extend the patient’s arm away from their body

Optional: place arm on a pillow

Ensure the arm is in a dependent position ( below body)

How can you identify and scan the basilic vein during an ultrasound exam?

• Confluences with the proximal brachial vein in the upper arm, then enters fascial layer

• Use the little finger as a landmark, vein runs along the medial aspect of both upper and lower arm

• Start in the antecubital space and follow medially

• May course posteriorly in the lower arm (note this in preliminary report)

• Extend patient’s arm away from body

  • Optional: place arm on pillow

  • Keep arm in a dependent position

What are the UEV mapping considerations for different pre-op procedures?

For Arterial Bypass Graft or CABG (Coronary Artery Bypass Graft):

• Only assess vein diameters

• Lower extremity veins (especially GSV) are often mapped first

For Dialysis Access Fistula (Pre-op for CKD patients):

• Assess vein and artery patency, course, and diameters

• Fistula connects artery to vein, creating high-pressure system for repeated needle access

• Used in chronic kidney disease patients with low renal function

• Dialysis = external blood filtration, often 6 hours, 4 days/week

What are the UEV Mapping Protocol additions for mapping for placement of Dialysis Access

Obtain longitudinal B-mode, Color Doppler and Spectral waveform and transverse AP and width diameter of

– Subclavian artery prox, mid and distal

– Axillary artery

– Brachial artery prox, mid and distal

– Radial artery prox, mid and distal

– Ulnar artery prox, mid and distal

• Important to ensure adequate vein and artery diameters as well as no venous thrombosis or significant arterial stenosis that would compromise blood flow to a dialysis access

What are the types of dialysis access, and how does vein mapping help determine the method? ( UEV)

Dialysis Access Types:

• Chest catheter

• Upper extremity fistula (requires UEV mapping first)

• Upper extremity graft

• Lower extremity graft

• Peritoneal dialysis (through abdomen)

Key Info:

• Dialysis requires repetitive needle access into a vein + high pressure

• AV Fistula (AVF): Native artery ↔ native vein

• AV Graft (AVG/DAG): Native artery → synthetic graft → native deep vein

• Vein Mapping Purpose:

  • Confirms if patient’s native vein is patent and large enough for a fistula

  • If too small, synthetic graft is used instead

What are the indications for vein mapping in a patient preparing for dialysis access?

• Performed pre-op for dialysis access fistula planning

• Assess arterial and venous diameters

• Determine preference and feasibility of access sites

Possible Access Options:

• Forearm Cephalic Vein Fistula

  • Non-dominant arm (preferred)

  • Dominant arm

• Upper Arm Cephalic Vein Fistula (dominant or nondominant)

• Upper Arm Basilic Vein Transposition Fistula (dominant or nondominant)

• Forearm Loop Graft

• Upper Arm Straight Graft

• Upper Arm Loop Graft (axillary artery to axillary vein)

• Lower Extremity Loop Graft (common femoral artery to vein

( if in yellow it uses both patients arteries and veins)

All of the above use the patients arteries

What is the Criteria for mapping for AVF (UEV)

Adequate vein diameter is 0.25 cm and greater

Adequate arterial diameter is 0.20 cm and greater

What is the "Fistula First, Catheter Last" campaign, and why is it important?

• Promotes early placement of AV fistulas in patients with declining renal function

• Goal: Have fistula ready and usable before dialysis is needed

• Alternative: Central venous catheter (Subclavian or Innominate vein)

  • Higher risks: More prone to occlusion and infection

• Encourages patients to meet with vascular surgeons early to avoid catheter use

What is UEV hemodynamics for inspiration and expiration

Inspiration: Increases venous return to right heart from upper

extremities

– Diaphragm lowers and decreases pressure in thoracic cavity

Expiration:

Decreases venous return to the right heart from upper

extremities

Diaphragm raises and increases pressure in thoracic

cavity

What is the UEV Protocol

B mode compression, Color Dolor and Spectral Doppler waveforms

with distal augment of

– IJV

– Innominate vein (Brachiocephalic vein)

– Subc vein at prox, mid and distal

– Axillary Vein

– Brachial Vein at prox, mid and distal

– Radial Vein

– Ulnar Vein

– Cephalic vein (upper arm prox mid and distal and lower arm prox mid

and distal)

– Basilic vein (upper arm prox mid and distal and lower arm prox mid

and distal)

Always do Bilateral SUBc veins even it’s a unilateral exam

What major vein can you locate by following the internal jugular vein (IJV) proximally toward the heart?

following the IJV proximally toward the heart, you can locate the innominate vein (also known as the brachiocephalic vein), which is also the origin of the subclavian vein

What is important to know about imaging the innominate (brachiocephalic) vein in upper extremity venous studies?

• Also called the brachiocephalic vein

• Cannot be compressed due to its location posterior to the sternum

• Must rely on Color Doppler and Spectral Waveform analysis

• Be sure to image the innominate vein proximal to the subclavian vein origin, not the subclavian vein itself

How is the subclavian vein evaluated in upper extremity venous (UEV) studies, and why is bilateral imaging important?

• Bilateral subclavian vein spectral Doppler is required to compare waveform phasicity

• Evaluates for proximal obstruction, especially since these veins are obstructed by the sternum

• Compression is typically not possible due to the clavicle, so rely on Color Doppler and Spectral Waveforms

What are key ultrasound characteristics of the brachial veins in upper extremity venous studies?

• Often paired but may have large branches

• Always follow the brachial artery—brachial veins stay adjacent to it

• Watch for the brachial nerve bundle and basilic vein

• Basilic vein travels into the fascia layer without an accompanying artery

What should you know about imaging the axillary vein during an upper extremity venous (UEV) exam?

• It’s the first compressible vein in the UEV protocol

• Innominate, IJV, and Subclavian veins are typically not compressible

• Diagnosis in non-compressible veins relies on hemodynamics (Color and Spectral Doppler)

• Position the patient with arm extended and abducted for better access

• Normal variant: Axillary vein may not lie directly adjacent to the axillary artery

How would you asses vein patentcy through compressions

Transverse compressions throughout vein (every 2 cm ) to ensure no thrombus

present

• If wall appears uniformly thickened with no evidence of thrombus, note on the report “thick walls” vs partially incompressible

• Possible causes of thickened vein walls: venous hypertension, inflammation from Behcet’s disease, phlebitis, or post-thrombotic syndrome

What considerations should be made during an upper extremity venous exam when a patient has a central venous catheter? ( venous thrombus from venous trauma)

• Increased incidence of axillary and subclavian DVT due to central venous catheters (e.g., PICC lines, dialysis catheters)

• Do not disturb catheters to avoid infection risk

• Document in report: “Cannot visualize proximal subclavian and innominate vein due to right shoulder catheter”

• IVs can commonly cause superficial venous thrombosis (SVT)

Whats being shown in this image, what does this indicate

small varicosities indicative of DVT. Likely indicative of Axillary or Subclavian obstruction as small collaterals enlarge to reroute blood blocked by obstruction

What is Paget-Schroetter Syndrome and how does it typically present?

• Also called Effort Thrombosis

• Most common cause of axillary-subclavian DVT in outpatient settings

• Caused by repetitive motion injury or clavicle impingement, sometimes linked to cervical rib abnormalities

• More common in men and in the dominant arm

• Symptoms: Arm pain and swelling, may be acute or vague/subtle

• A form of venous thoracic outlet syndrome (TOS)

What are key sonographic and treatment considerations for Paget-Schroetter Syndrome?

• Clavicle may limit visualization, so rely on Spectral Waveform analysis

• Do not abduct the arm during exam—abduction may cause continuous waveforms that mimic proximal obstruction

• Treatment options:

  • Anticoagulation therapy

  • Thrombolysis

  • First rib resection (decompression)

  • Balloon angioplasty

What is Superior Vena Cava Syndrome (SVCS), and how is it caused, diagnosed, and treated?

Definition: Compression of the Superior Vena Cava (SVC)

Causes:

• Thoracic cancers

• Repeated central venous lines

• Compression by nearby structures

Symptoms:

• Gradual onset of facial and arm swelling

• Heaviness in upper extremities

• Visible collateral veins on skin

• Coughing, dyspnea, lightheadedness, confusion

Diagnosis:

• Use Spectral Doppler of bilateral subclavian veins

  • Minimal, monophasic waveforms

  • Low amplitude with little cardiac influence

• Direct SVC visualization is difficult due to its location behind the sternum

Treatment:

• Venography with balloon stenting

• Post-op success = return of respirophasic waveforms with normal amplitude in both subclavian veins

What is a fibrin sheath, and how is it identified and managed in vascular imaging?

• A fibrin sheath forms around central lines, catheters, and ICD leads

• Commonly seen in the internal jugular (IJ) and subclavian veins

• Can disrupt venous flow

• Not a thrombus, but a collection of fibrin that remains even after catheter removal

• Should be documented with cine loops and monitored over time

• Contrast-enhanced catheter venography is the gold standard for official diagnosis

What is Hemodialysis?

Minimally invasive procedure

• Cleans excess fluid and waste material from the blood through

a semi-permeable membrane

– Known as a “dialyzer”

• Bridge to transplant for renal failure patients

Why is dialysis needed?

Patients who undergo dialysis are unable to adequately excrete

waste products through urine

• Without dialysis patients will:

– Experience azotemia (build up of waste in the blood)

– Experience uremia ( ill feeling secondary to azotemia)

– Eventually pass away

• Patients are weighed before and after dialysis with measurable

weight loss following procedure

Whats the difference between fistula and graft

Fistula = patient’s native artery and vein

Graft= patient’s native artery and synthetic vein material

If you don’t know, “dialysis access” refers to either

• Vein mapping determines if a patient’s own vein is patent and large enough for a dialysis fistula, if too small then synthetic material used instead

What patient history factors affect the selection of location and type of dialysis access?

• A new access cannot be placed distal to an old one

• Previous grafts may cause stenosis (possibly why a new access is needed)

• Increased risk of infection near previous access

• Compromised venous flow can lead to swelling and reduced dialysis efficiency

• Surgery is more complicated in areas with previous access

What is the selecting criteria for dialysis access

• Non-dominant arm used first

• Vein diameter >0.25cm

• Arterial inflow adequate

– >0.2 cm with no significant stenosis

What are AV fistulas advantages and disadvantages

Native artery and native vein

Advantages: Lower infection rate, Higher blood flow rates, Lower thrombosis/stenosis rates

Disadvantages: Longer maturation time (time before it can be used for dialysis), Potential for steal syndrome, Aneurysmal formation

How is dialysis performed using a fistula or graft?

• Two large-gauge needles are inserted into the fistula or graft

• The distal needle removes blood and sends it to the dialysis machine

• The proximal needle returns the cleaned blood to the body

• Needles puncture only the vein or graft material, not the artery

What structures are involved in dialysis access, and how is it similar to an arterial bypass graft? What does the distal part do?

• Involves an arterial anastomosis (where blood is removed from the artery and enters the graft or fistula)

• Involves a venous anastomosis (where blood returns from the graft into the vein)

• Can use a patient’s vein or synthetic graft

• Has both a proximal anastomosis (near the heart, for blood entry into the graft) and a distal anastomosis

What does the distal part do?

• The distal anastomosis refers to the artery beyond the access site, which supplies blood to the hand or lower extremity

• It’s crucial to assess this area because dialysis access can steal blood from distal circulation, potentially leading to hand ischemia (steal syndrome)

What are the 4 key areas to evaluate in dialysis access hemodynamics?

1. Arterial inflow

2. Dialysis access (graft or vein)

3. Venous outflow

4. Distal arterial supply

What should arterial inflow and venous outflow waveforms look like in a functioning dialysis access?

They should be inverse waveforms of each other due to the loop created by the access, assuming no obstruction

What arteries are evaluated for arterial inflow in dialysis access, and how are they affected?

• Start evaluation at the subclavian artery and follow down to the proximal access anastomosis

• All arteries proximal to the access are affected by the dialysis circuit:

  • Upper arm access: subclavian, axillary, brachial

  • Forearm access: subclavian, axillary, brachial, and radial or ulnar artery

What are normal and abnormal arterial waveform findings near a dialysis access?

• Normal: Low-resistive waveform with increased diastolic flow and elevated peak systolic velocity

• Abnormal: High-resistive waveform may suggest distal access obstruction