IR Flashcards
how is size measured for puncture needles, catheters, dilators, sheaths, wires.
- puncture needle- Gauge. Outer
- catheter/dilator- French. Outer
- sheath- F. inner (Shy and stays in Shell)
- wires: outer diam (inch), length (cm). standard=0.035in and 180cm
T or F: larger the gauge, smaller the wire. Larger the F, larger the catheter.
True
how many inch = 1 mm. How many F = 1 mm
- 0.039 inch
- 3F
how are wires sized? what is the standard wire size for general purposes
- outer diam=inch. Standard= 0.035 inch
- length =cm, standard=180 cm
size of microwires
0.018, 0.014 inches
What size catheter will the standard 0.035 wire fit through?
4F (or bigger)
when are sheaths used? How are they sized?
- cases that require exchange of multiple catheters w/o losing access
- sized via inner lumen. Chosen according to largest catheter they will accommodate
- outer diameter usually 1.5-2F larger than inner lumen, ieL add 2F for outer diam (if you want to know how big the hole in the skin will be)
some conversions… How many F?
- 16G needle has outer diam of 1.65 mm
- 20G needle has outer diam of 0.97 mm
- 5F
- 3F
18G, 19G (seldinger technique) and 21G (micro puncture) needles accept what size guide wire?
- 0.038 in
- 0.035 in
0. 018 in (micropuncture)
when is micro puncture good and bad?
- Good-tough access (Ex: antegrade femoral puncture), lack of experience, anatomically sensitive (internal jugular, dialysis access)
- bad: scarring, obesity, flimsy 0.018 inch guide wire doesn’t give enough support for dilator when upsizing
2 flavors of guidewires
- non-steerable (supportive raises for catheters)
- steerable-tight spots, ex: hydrophilic
“long wire” length and uses
- 260 cm
- upper extremity from groin access, visceral circulation and need to exchange catheters, guide catheter >90cm, through and through situation (body flossing)
minimal guidewire length
-length of catheter + length of guide wire in pt
what’s more likely to cause dissection: short or long floppy tip guidewire
shorter
which guide wire for “tight spots”
hydrophilic
how should stiff guide wires be introduced?
through a catheter
Advantage of J tip guidewires. Significance of number associated with it?
- Don’t dig up plaque and miss branch vessels
- radius of curve (smaller miss small branch vessels, larger miss large branch vessels)
guidewire stiffness: noodle-like, normal, supportive, stiff, hulk smash
- Bentson (floppy tip) (BENdy)
- hydrophilic (standard 0.35 J or straight)
- stiff hydrophilic (heavy duty J or straight)
- flexfinder. Abplatzen stiff or extra stiff. 0.018 platinum plus. V18 shapeable tip
- hulk smash-lunderquist, back up Meier.)
more guide wire stiffness, more…
dissection
use of lunderquist (super stiff) guide wire?
-aortic stent grafting
catheter types
- nonselective (medium and large vessels)
- selective (diff shapes/angles for “selecting” branch vessel)
nonselective catheter types
- pigtail
- straight
selective catheter types
- end hole
- side + end hole
- acute angle (<60˚), curved (60-120˚), obtuse (>120˚)
what happens if you consistently inject through a pigtail
contrast goes out proximal side holes and not the tip –> con’t injection=clot in tip
what should you do before big injection with pigtail Cath?
-small test injection-make sure you’re not in a small branch vessel (pigtails are for medium/large vess)
what if pigtail fails to form as you retract the wire?
push catheter forward while twisting
morphology and utility of straight catheters
- side holes and end hole
- smaller vessels, classic loc=iliac
end hole vs side & end hole selective catheters
- end hold: hand injection. dx angiograms & embolization procedures
- side + end hold- pump injection. SMA angiogram. never use in embolization (material can track out side hole)
utility of angled tip, curved, and recurved selective caths
- angled (<60˚)- aortic arch vessels
- curved (60-120˚)- renal, ?SMA/celiac
- obtuse (>120˚)- celiac/sma/ima
“recurve”
1˚and 2˚ curves
- co-axial system
- guide catheter
- introducer
- microcatheter
- vascular sheath
- 1 catheter inside another catheter/sheath. Ex: catheter inside an arterial sheath
- large catheter guide up to desired vessel then shaped for more conventional distal cath
- introducer=long sheath
- microcath-2-3F for tiny vessels (super selection of peripheral or hepatic branches)
- sheath + hemostatic valve + side arm for flushing
20 for 30
20 cc/second for total of 30 s
-bigger artery, higher rate (try to displace 1/3 of blood per second to get adequate picture)
how are maximum flow rates determined and what is flow rate for 3F, 4F, 5F?
- internal diam, length and #side holes
- 8 mL/s, 16, 24 (~8/F)
Double vs single flush techniques
- double: aspirate –> attach new saline syringe (for neuro stuff) –> flush
- single: aspirate –> tilt 45˚ –> flush w/ SALINE only
what if you accidentally mix blood in with saline on aspiration?
discard syringe and double flush
what if you’re unable to aspirate blood?
1) jammed against side wall-pull back, manipulate cath
2) clot- pull out/clear clot OR blow clot inside (if embolizing that location anyways)
preference for picc line venous access
basilic > brachial > cephalic
preference for central lines/ports
- RIJ > LIJ > REJ > LEJ > Femoral > subclavian
- subclavian=thrombus, PTX
- femoral=infection
dose thrombin injection into pseudoaneurysm
-0.5-1 mL (500-1000u)
when should you not compress a pseudoaneurysm?
above inguinal lig
CI to thrombin injection
- local infection
- rapid enlargement
- distal limb ischemia
- large neck (first for propagation)
- pseudoaneurysm cavity size <1cm
when is surgery indicated for pseudoaneurysm rx
- thrombin fails
- inf
- tissue breakdown
- aneurysm neck too wide
mc arterial access site
femoral
femoral access too high or low
- high (above inguinal lig)-RP bleed
- low: AV fistula
steps when meeting resistance when advancing guide wire during arterial access
1) stop, pull wire out and confirm pulsatile flow
2) will not advance beyond top of needle- flatten needle (negotiate plaque)
3) stops after short distance-fluoro to confirm pw. 4F sheet. hydrophilic wire.
when would you want to do brachial access?
1) fem a out
2) obesity
3) upper limb angioplasty
risks brachial access
1) compartment syndrome
2) stroke if cath passes across GV/arch
3) spasm (small vessel. pox GTN)
* sheat larger than 7F may require surgical cut down
which arm do you use in brachial a access
- left if heading south (abd aorta or LE)
- right if headed north (thoracic aorta or cerebrum)
- equal?-left (non dominant, avoid cerebral vess)
- BP diff >20mmHg systolic sugg stenosis-use other arm
Radial access
1) no bedrest
2) allen test
CI to trans lumbar aortic puncture?
supra celiac aortic aneurysm
approach to trans lumbar aortic puncture?-pt position, spine level?
Prone, left side (avoid IVC)
-high-T12 endplate
mild backache s/p trans lumbar aortic puncture
-psoas hematoma (common)
arterial access anticoagulation pre-procedural requirements
- heparin 2 hrs (PTT < 1.2x 25-35s). can turn on 2 hrs after
- INR 1.5
- coumadin 5-7 d (vit K 25-50 mg IM 4 hrs, FFP/cryo)
- PC >50K
- ASA/plavix 5 d
when do pseudoanuerysms spon’t resolve and resp well to intervention?
<2cm
long narrow neck, small defect
ideal degree of balloon dilation
- 10-20% over normal a diameter
- take out stenosis + stretch a slightly
anticoagulation s/p angioplasty
-1-3 mo anti-platelets (AsA, clopidogrel)
general indications for angioplasty
- 50% stenosis + syxs
- a gradient > 10
- v gradient > 5
where do you not stent
- across joint
- site of possible surgical bypass
exception to angio + stent
FMD
stent types
1) balloon-precise deployment, ex: renal ostium
2) self-expandable- areas that get compressed (ie: superficial loc, ex: cervical carotid or SFA)
closed vs open cell stents
- closed-every segment connected by link. More radial force, less flexible, greater plaque coverage
- open= some stent segments deliberately abscenct-flexible/conforms to tortuous vess, less radial F)
ninitol
used in self-expanding stents vial thermal memory (soft at room T, more rigid at body T)
drug eluting stents
-retard neointimal HP
rough guessing guide for balloon size selecting-aorta, common iliac, ext iliac, CFA/prox SFA, distal SFA
- aorta: 10-15mm
- CI: 8 mm
- EI: 7 mm
- CFA, prox SFA=6mm
- distal SFA=5mm
- popliteal=4mm
stent size selection
- 1-2 cm longer than stenosis
- 1-2mm wider than unstenosed vess
next step: >30% residual stenosis
- pressure gradiant-if normal, stop
- if abN-elastic recoil–> stent
next step: waist won’t go away w/ balloon inflation
switch balloon to higher P or cutting
next step: distal embo
- angiographic run –> limb perfused? no intervention.
- not perfused? IL access and retrieve clot
next step: extravasation in setting of balloon angioplasty
-reinflate balloon
EVAR
endovascular abdominal aortic aneurysm repair
-includes iliacs
TEVAR
thoracic endovascular aortic aneurysm repair
anatomy criteria for EVAR
-proximal landing zone must be 10 mm long, non aneurysmal, <60˚ tortuosity
endograft vs open repair
- endo repair: 30 d mortality less
- aneurysm related mortality equal
- graft complications/re-intervention-higher w/ Endo
requirements of iliac vessels in setting of endograft device deployment
- iliac vessels have angulation >90˚ (esp in heavily calcified)
- iliac a diameter < 7mm -may need to cut down and place temporary conduit
absolute CI to infrarenal EVAR
- landing site won’t allow for aneurysm exclusion
- covering a critical a (IMA in setting of SMA + celiac occlusion, accessory renal feeding a horseshoe, dominant lumbar arteries feeding the cord)
describing aneurysms near renal
- para-renal-umbrella term near renals
- juxta renal- short neck (<1 cm) or encroaches on renal
- suprarenal- involves renal and ext into mesenterics
- crawford type 4 thoracoabdominal aortic aneurysm-ext from 12th intercostal space to iliac bifurcation w/ involvement of orgs of renal, SMA, and Celiac
crawford type 4 thoracoabdominal aortic aneurysm
ext from 12th intercostal space to iliac bifurcation w/ involvement of orgs of renal, SMA, and Celiac
when does paraplegia occ in setting of EVAR. Next step?
- artery of adamkiewicz territory covered (T9-12)
- next step=CSF drainage
vertebral level take off: celiac, sma, renal, ima
- T12
- L1
- L2
- L3
most common type of endoleak
type 2
which endoleaks must be treated?
- High flow, emergently: type I and III
- observe type 2, treat if enlarging
- type IV resolve ~48 hrs
embolizations options in setting of big vessel
permanent: coils (lung AVM)
temporary: gel foam pledget (trauma)
embolization options in setting of small vessel
- permanently kill: liquid (RCC ablation)
- permanently wound: particles (fibroid embo)
- temporary: microsphere (chemo)
embo option to slow flow but not occlude
- large proximal embolic (coils, plugs, large particles 500-100µm)
- ex: GI bleed
embo option to totally infarct
- distal embolic small particle, <250µm
- ex: tumor ablation
coils
permanently occlude large vessels
- diff sizes and shapes
- push via coaxial system OR chased via saline bolus if exact precision not needed
- complex: pack behind amplatzer or use as scaffolding to hook small coils to a large one
coil vs microcoil
- deployed via standard 4-7F cath
- micr: deployed via microcath. I f you try to to deploy standard cath and ball up inside thing and clog it
which coil to use in setting of accurate deployment
End hole detachable coil
device from which a coil should never be deployed
-side hole end hole.
amplatzer vascular plug (AVP)
- self expanding wire mesh made of nitinol mounted at end of delivery device/wire.
- when deployed: shrinks in length, widens
- use: high flow station when killing a single large vessel. Going to need a lot of coils to take that beast down.
particulate agents
- temporary- gelfoam, autologous blood clot
- permanent-PVA particles
- use: want to block mult vess, ex: fibroids
gel foam powder vs gel foam pledgets/sheets
powder- causes occlusion at capillary level (tissue necrosis)
-pledget/sheet-occlusion at arteriole or larger level (infarct less common)
when do you stop deploying deploying particulate agent
“to and fro”- if you get total occlusion, you risk refluxing
coils vs PVA particles
- size: coils for medium to small arteries. PVA for small a’s to caps
- need for repeat
next step: what do you do after placement of occlusion balloon in setting of particle embolization?
test injection to confirm adequate occlusion
liquid agents
- sclerosants-absolute EtOH (it hurts) and sodium dodecyl sulfate (SDS)
- non-sclerosants- onyx (ethylene-vinyl Alocohol copolymer), ethiodol
how do sclerosis agents work?
near immediate thrombosis/irreversible endothelial destruction
-nontargeted embo=devastating: know anatomy, f angiograms, balloon occlusion
what do you do prior to deflating occlusion balloon in setting of sclerosing agents?
-aggressively aspirate (w/ 60 cc syringe) to make sure all poison is out
onyx
- non sclerosant liquid embo agent used in neuro procedures.
- dries slowly (outside in) allowing for controlled delivery
ethiodol
- non sclerosant liquid embo agent. Oil that blocks vessels at arteriole level (same as small PVA particles)
- hepatomas love it
- radio-opaque- decreases non-target embolization, track tumor size on f/u
post-embolization syndrome
- pain/n/vom/low grade fever
- rule of 3
- classic for large fibroid
- ppx w/ anti=pyrexial, antiemetic
frequent limb embolic sites
- CF bifurcation
- popliteal trifurcation
triaging limb ischemia based on physical exam
- category 1 (viable)
- category 2a (threatened). Salvageable.
- category 2b-(threatened.) salvageable if immediate intervention
- category 3 (irreversible)
Category 1 limb ischemia
Viable. Not threatened.
- Capillary return in tact.
- No m paralysis or sensory loss.
- a doppler +
- v doppler +.
category 2a limb ischemia
Threatened. Salvageable.
- cap return intact/slow
- M paralysis (-)
- sensory loss-partial
- arterial doppler (-)
- venous doppler (+)
category 2b limb ischemia
Threatened. Salvageable if immediate intervention
- cap return slow/absent
- m paralysis-partial
- sensory loss-partial
- a doppler (-)
- venous doppler (+)
category 3 limb ischemia
Irreversible/not salvageable/amputation
- cap return (-)
- m paralysis (+)
- sensory loss (+)
- arterial doppler (-)
- venous doppler (-)
“critical limb ischemia”
rest pain for 2 wks (or ulceration or gangrene)
treating limb ischemia: inflow vs outflow
inflow first
surgery vs thrombolysis limb ischemia
- occluded <14d-thrombolysis
- occluded > 14d-sx
- isolated suprainguinal embo-sx
- fragmented distal emboli-thrombolysis
choosing values for ABI
- BP both arms & ankles. systolic measurement.
- use higher arm
- use higher dorsals pedis or pst tibial
categorizing ABI severity:
- N. ø syx
- 0.75-0.95-Mild. mild claudication.
- 0.5-0.75-moderate. claudication.
- 0.3-0.5-moderate/severe. severe claudication.
- <0.3-severe/critical. rest pain
toe pressure
- distal toe P in diabetics (these a’s not affected)
- N values: systolic >50mmHg, TBI > 0.6
at what toe pressure is ulcer less likely to heal?
<30 mmHg
segmental limb P
- modification to standard ABI
- pressures at thigh, calf, ankle
- drop of 20-30 mmHg-infer level
what makes limb spectral waveform triphasic?
high resistance tibial vascular tree-rebound effect via normal arterial compliance.
-lost in setting of PAD
ulcer location: venous stasis, ischemic/infected ulcer, neurotrophic ulcer
- medial ankle
- dorsum of foot
- plantar (sole)
Rutherford and fontaine?
categories and classification of sgx and syx PAD
post-op bypass vocab: primary patency
uninterrupted latency of graft with no procedure done on the graft itself
-repair of distal vessels or vessels at either anastomosis does not count as loss of primary latency
post-op bypass vocab: assisted primary patency
Patency never lost but maintained by ppx (stricture angioplasty, etc)
post-op bypass vocab: secondary patency
graft latency lost, then restored with intervention (thrombectomy, thrombolysis, etc)
best route of access for mx threatened limb: iliac
- IL CFA (1st choice)
- CL CFA
best route of access for mx threatened limb: CFA
CL CFA
best route of access for mx threatened limb: SFA
IL CFA
best route of access for mx threatened limb: fem-pop graft
IL CFA
fem-fem cross over
- direct stick (1st choice)
- inflow CFA
best route of access for mx treated limb
shortest, most direct
When would you use CL CFA for treating a lesion in setting of threatened leg
1) The IL CFA is occluded
- pt fat
antegrade vs retrograde access
- arterial flow
- antegrade=towards toes
- retrograde=towards heart
check angiography
-infusing TPA directly into clot. Check every 6-8 hrs for progress
what if you can’t cross the clot with a wire
it’s organized and probably won’t clear with thrombolysis
lytic stagnation
- clot not clearing during check angiogram
- stop the procedure
what if pt develop confusion in setting of thrombolysis
non-con ct
what if the pt level hypoTN and tachycardia in setting of TPA
- bedside eval
- ct abd/pelvis
- stop tpa
what’s the end point for tpa?
-typically stop after 48 hrs (even if not totally cleared)
varicose v treatment-“tumescent anesthesia”
- lots of diluted subcutaneous lidocaine provided
- ablated via endoluminal heat source
CI to varicose v rx?
-DVT
complications dVT
- acute PE
- chronic post thrombotic syndrome
predictive models for CTPA
- wells
- thrombus density ratio
Thrombus density ratio
DVT HU : normal v HU > 46.5 ==> likely a PE
phlegmasia alba
painful white leg seen in setting of massive DVT
- ø ischemia
- preserved collateral v’s
phlegmasia cerulea dolens
painful blue leg
-complete thrombosis of deep venous system, including collaterals
when are plegmasia alba and cerulean dolens terminology used?
- extreme sequela of May-Thurner
- any sitch w/ massive DVT, ie: pregnancy, trauma, malignancy, clogged IVC filter
post thrombotic syndrome (PTS)
sequelae of DVT.
- pain, ulcers
- RFs: >65 yo, prox DVT, recurr/persistent DVT, fat
- 6 mo-2yrs s/p DVT
what is done to prevent pst thrombotic syndrome
- catheter-directed intrathrombus lysis of iliofemoral DVT
- (not needed for femoropopliteal)
permanent vs retrievable vs temporary filters
- permanent-do not come out (10% thrombus w/I 5 yrs)
- retrievable-can but don’t have to.
- temporary-will come out. Component sticks outside body to retrieve
when are suprarenal IVCs placed?
- pregnancy-avoid compression
- clot in renal or gonads-get above clot
- duplicated IVCs
- circumaortic left renal v
risk of suprarenal ivc filter
renal v thrombosis (not at all proven)
ivc filter used based on IVC size
- IVC < 28 mm-any
- bird’s nest if bigger, up to 40mm
gunther tulip & Simon nitinol ivc filters
GT: superior end hook for retrieval
SN: low profile (7F), placed in smaller v’s (arm)
are IVC filters MRI compatible?
yes
check list bf placing filter
1) confirm IVC patency
2) measure IVC size
3) confirm 1 IVC
4) document position of renal v’s
complications/risks of ivc filters
- malposition-tip at renal v
- migration-heart requires sx. otherwise snare
- thrombosis-caval thrombosis=CI to removal; requires lysis
- ivc perforation-problem if aortic, ureteral, duodenal, lumbar vessel
- filter infection-bacteremia=relative CI
steaming effect
unspecified blood entering renal v’s let’s you infer correct position of IVC filter
IVC removal-first step
angiogram-evaluate for clot
- > 1 cm3=stays in
- <1 cm3= comes out
next step: meet resistance when removing IVC filter
stop
what should be done after IV filter removal?
angiogram-confirm no rupture
- if rupture: angioplasty–> covered stent
- if wall injury/dissection–> anticoag
MC dialysis AV fistula
radial a – cephalic v
pros of AV graft
- use w/I 2 wks
- easier to declot (thrombus usually confined to graft)
comps of AV graft
- less longevity (only 50% latency at 2 yrs). Require higher flow rates to remain patent
- HP venous intima or dostreat from graft v anastomosis–> stenosis, obstr
- inf+ (foreign)
- 6-10x (+) risk inf, thrombus
pros of AV fistula
-last longer, more durable
con’s of AV fistula
-3-4 mo maturation
when should you obtain diagnostic fistulogram in setting of AV graft/fistula slow flow?
- graft: <600 cc/min
- fistula: <500 cc/min
why do AV grafts/fistulas fail?
hyperplasia –> stenosis/occ/thrombus
*all must die
why’s a normal physical exam for AV graft
- easily compressible pulse
- low pitched bruit (systole & diastole)
- thrill-palpable w/ compression only at arterial anastomosis
high pitched bruit
stenosis
swollen arm, chest, cw collaterals in setting of av graft/fistula
central venous obstruction
where is the problem usually in av grafts?
venous outflow
if you fix a stenotic av fistula, they’re good to go, right?
reoccur 75%
systolic thrill in av fistula
stenotic.
should be con’t at anastomosis
2nd thrill in av fistula
another stenosis. should only be 1
steal syndrome in setting of av fistula
- blood preferentially going to fistula due to stenosis in native artery distal to fistula –> cold painful fingers.
- rx= sx. distal revascularization and interval ligation of extremity (DRIL), or flow reduction banding.
CI to accessing/treating av fistulas/grafts
- infection=absolute
- <3- d
- long segm 7 cm stenosis
what dir do you access av graft
- toward venous anastomosis, ie: antegrade
* assuming v is the problem, which it usually is
how do you look at arterial anastomosis
obstruct venous outflow –> contrast reflux into artery
what are moves for angioplasty of a narrow spot?
- heparin 3000-5000u
- exchange cath for 5 or 6F sheath over standard 0.035
- dilate w/ 6-8 mm balloon
when do you place stent in setting of av fistula/graft stenosis
1) bad elastic recoil
2) recurrent stenosis w/I 3 mo angioplasty
role of nitro in av fistula/graft stenosis
differentiate spasm vs stenosis
what’s considered a success rx for av fistula/graft stenosis
1) improved syxs
2) <30% residual stenosis
av fistula/graft aneurysms
surgically fixed
portosystemic gradient (PSG)
P difference btw portal v and IVC
-3-6 mmHg = N
portal HTN
- portal v > 10 mmhg
- PSG > 5mmHg
- PV > 1.3-1.5 cm, splenic v >1.2 cm, big spleen, ascites, porosystemic collaterals, slow (<16 cm/s) or reversed PV flow
Portal hypertension: Increased pressure gradient between portal and hepatic veins (> 10 mm Hg)
Portosystemic gradient = direct portal pressure - right atrial pressure
Hepatic vein pressure gradient = wedged hepatic vein pressure - free hepatic vein pressure
Estimate of portosystemic gradient
indications for TIPS
1) varicocele hemorrhage refractory to endoscopic rx
2) refractory ascites
3) budd chiari
preprocedural steps for TIPS
- echo- heart failure
- cross sectional img-confirm patency of portal v
ideal pressure s/p TIPS
-<12 mmHg is the goal (9-12)
TIPS acronym
transjugular intrahepatic portosystemic shunt
why don’t you turn cath pst in TIPS?
- PTX
- miss PV
MELD vs Child Pugh
- Child-Pugh=older. less accurate. eval liver dx severity
- MELD- liver and renal fx
MELD
-initially developed to predict 3 mo mortality in TIPS. now used to prioritize who gets a tx
-bili, INR, creatinine
>18= high risk early death (even s/p tips)
Child Pugh
- initially used to determine tx urgency
- now can predict TIPS outcomes
- eval liver dx severity: bili, alb, PT, ascites, hepatic enceph
- class B & C RFs for vatical hemorrhage
absolute CIs to TIPS
- severe heart failure (RHP 10mmHg)
- severe liver fx (MELD >18, CP B,C), total bilirubin >3mL/dL
- sev encephalopathy
- severe ind-uncontrolled systemic inf
relative TIPS CIs
- cavernous transformation
- isolated gastric varicose w/ splenic v occlusion
- sev hepatic enceph
main acute post procedural compl TIPS
- cardiac decomp ((+) RH filling)
- accelerated liver fx
- worsening hepatic enceph
normal TIPS eval
limited 2wks (air bubbles mimic occlusion)
- 1 mo, 3 mo, 6 mo
- flow into stent 90-190 cm/s
sgx’s of TIPS stenosis/malfucntion
- > 200 cm/s
- PV < 30 cm/s
- temporal (+) or (-) >50 cm/s
- “flow conversion”-PV away from shunt
- new/increased ascites (indir sgx)
where is TIPS stenosis
- usually hepatic v or TIPS tract
- >12 mmHg
How to treat TIPS occlusion, flow limited stenosis, severe encephalopathy
- occlusion-thrombolysis + angioplasty
- flow limited stenosis- angioplasty
- TIPS reduction
TIPS induced hepatic encephalopathy
- gradient too low
- add stent
peritoneovenous shunt
alternative to TIPS for refractory ascites
- ascites –> jug v
- inf, thrombosis
balloon occluded retrograde transverse obliteration (BRTO)
- aims to drive blood into liver (to help w/ se’s of extra hepatic shunting)
- gastro-renal shunt required: access –> venogram –> sclerosed gastric varices
- improves hepatic encephalopathy
mc side effect and compls of BRTO
- MC SE: hematuria
- compl: worsening es varices & ascites
biliary duct variants
- right pst duct drains into left duct
- trifurcation
where to stick when placing biliary drain/cholangiogramx
- R side: r flank/mid axillary line below 10th rib.
- left: substernal/subxyphoid
purpose of punching additional hole in proximal biliary drain
ensure drainage
benefit of internal/external biliary drain vs straight drain or pigtail
cross lesions. stable. conversion to internal
benefit of internal biliary drain
-save bile salts
ascites in setting of biliary drain placement
- excessive: drain
- small: eval with US. If up against peritoneum–> R side. If not, L side
Right approach biliary drain w/o filling left ducts
R side up (unless known obstruction)
full rigor after injection in setting of PTC
cholangitis-aggressive resus, place drain, ICU
next step: you encounter stones during PTC
-dilute to 200-240 mg/mL to avoid obscuring filling defects
next step: can’t cross obs in setting of biliary drain
-place drain, let cool down (48 hrs)
cholecystostmy routes
- transperitoneal-less stable (more spillage)
- transhepatic (segm 5 and 6; transverse the bare area)
managing bile leak
tube in ducts
chilaiditi syndrome
bowel interposed in front of liver/gb. ?CI to PC
PC length of time
- 2wks (bile leak)
- cholangiogram to confirm cystic duct patent.
- clamp 48 hrs
fine need aspiration needle size
21 or 22G
targeting a peripheral liver lesion for bx
-2-3 cm normal liver first (bleed)
kehr sign
shoulder pain >5 mins after liver bx, sugg bleed
indication transjug liver biopsy
- severe coagulopathy
- massive asites
- massive obesity
- mechanic ven
- need for additive vascular procedures (TIPS)
- failed prior precut attempt
added benefit of transjug liver bx
-measure hepatic venous P
indications hepatic embo in setting of trauma
- con’t hem, borderline stable post resus
- failed surgical attempt
- rebleed
- aneurysm, AVF (don’t have to be actively bleeding!)
problem with massive non-selective hepatic a embo?
liver abscess (already common after injury)
risk of coils in PA sac
- late rupture
- goal: distal and prox parent vess (“sandwich tech”)-distal first!
why can hepatic PAs be treated at site of injury
bc not end arteries (no collaterals)
-use sandwich tech
focal vs mult bleeding sites in setting of splenic rupture
- focal embo
- mult: amplatzer plug in splenic a prox to short gastric a’s (slows flow –> clot)
HCC rx
- tace
- rfa
- tace + RFA
- Y90
liver tx indications
- <65 yo
- limited tumor burden (1 tumor 5cm(-) or up to 3 tumors < 3cm)
TACE composition
-chemo + lipiodol. followed w/ particle embo
absolute CI to TACE
decompensated liver fx
+/- PV thrombosis (if sufficient septic collateral flow)
who’s at risk for biliary abscess in setting of tace
- biliary stent
- px sphincterotomy
- pst Whipple
“sterile cholecystitis” or “chemical cholecysitic” in setting of TACE
injected prox to cystic a
who does better: tace or systemic chemo
TACE
where do people get skin burns in setting of TACE
left back via RAO camera angle
RFA in HCC
- HCC + colorectal mets
- heating to 60˚C
TACE + RFA
HCC lesions > 3cm do better than either alone
prethreapy w/u for Y-90
1) Tc-99 MAA to hepatic a –> pulm shunt fraction of >30Gy too much
2) ppx embo R gastric and GDA
R gastric a variants
proper hepatic or leg heaptic
cure vs debulking
cure < 4cm
debulking > 4cm
RFA target, ie: burn margin size
need burn margin 0.5-1 cm
CI to RFA
- vascular hilum
- near gb
- superficial (near bowel)
grounding pad in rfa
blanket btw arms/body and btw legs to prevent close circuit arcs/burns
hot withdrawal
leave rfa probe on while removing probe to burn tract –> decr tumor seeding
heat sink
lesions near bleed vess 3mm+ treated less bc blood removes heat
Temperature limit on RFA
100˚C
-if greater: carbonize tissue near probe, reduce electrical conductance
post ablation syndrome-when does it start?
~2-3 wks after
microwave vs RFA
microwave. ..
1) generate more power
2) bigger lesions
3) less ablation time
4) less sup to heat sink
5) no ground pad
cryoablation
compression of argon gas. Thawing is what kills the cancer
-probe placement –> bx –> rx
cryoablation vs RFA
Cryo…
- hurts less (less sedation)
- (+) bleeding-bc not ablating small vess
“residual tumor”/”incomplete treatment” vs “recurrent tumor”
- focal enh on 1st post-rx study
- recurrent: new from 1st post rx study
expected tumor size change s/p RFA
- 4 wks-bigger (reactive edema, etc)
- 3 mo-same size
- 6 mo-smaller
- if residual: repeat rx (assuming no CI)
benign periablational enhacement-what is it, what’s it look like?
expected post RFA enh around periphery of ablation zone. Smooth, uniform, concentric
TACE post treatment CT
- lipiodiol: denser :). beam hardening a problem.
- zone of ablation
cryoablation treatment resp-f/u timeframe, app on CT/MR, size change
3 mo, 6 mo, 12 mo
- ablation spot lower density to kidney OR T2 (-), T1 ~/+
- size: incr –> same –> smaller
methods for G tube placement
1) radiographically inserted
2) perioral route
radiographically inserted G tube proceure
- cup of barium night before to outline colon
- drain ascites if present
- target: left of midline (ie: lat to rectus m to avoid inferior epigastric)
- mid to distal body. equal distance from greater to lesser curves (avoids Arties)
1) NG tube. inflate until stomach against wall
2) spear, secure gastric body to wall w/ 4 “t-tacks”
3) spear –> wire –> dilate
4) remove t-tacks s/p 3-6 wks
*12-hrs fasting post placement
most pst portion of stomach
cardia
perioral g tube placement
stab stomach –> treat wire up es –> grab wire, slip tube over it, advance into stomach all the way out stabbed hole
esophageal stent-ideal length
length 2 cm longer than lesion on each side
- oral contrast to outline lesion
- amplatz sire in stomach
- pre-stent angioplasty up to 2mm to invoke coughing/stridor if tumor near carina
- if tumor in upper 1/3-avoid larynx
- endoscopy or smaller device
-remove stent if dropped into stomach and pt syx
esophageal stent occlusion-causes (acute vs chronic), next steps
- acute: food impaction.
- chronic: tumor progr
-esophagram –> endoscopy –> 2nd stent
pseudo v sign
active GI bleed
- angiography appearance of v created by contrast pooling in gastric rug or mucosal intestinal fold
- persists beyond venous phase
Dieulafoys lesion
monster artery in submucosa of stomach, tears on pulsation, bleed a lot
- lesser curvature
- clips or embo
cause of pancreatic arcade bleeding aneurysm
celiac artery stenosis
celiac a compression (median arcuate lig) association
- pancreatic duodenal arcades via celiac stenosis
- filling of dilated pancreatic duo collateral system and retrograde filing of hepatic a on injection in SMA
bleeding rate perceivable by bleeding scan, CTA, angiography
- bleeding scan: 0.1 mL/min
- CTA: 0.4 mL/min
- angriography: 1mL/min
obscure GI bleed
small bowel (AVM)
- CTA and capsule endoscopy most appropriate
- Tc-99m RBC scan reasonable alternative (active bleed)
left vs right sided lower GI bleed
- left: diverticulosis
- R: angiodysplasia (early draining v)
mx angiodysplasia
-embo rarely stops it, easily recur. need surgery
findings angiodysplasia
1) early filling v (45 s)
2) dilated tortuous slow emptying intramural v
3) vascular tufts/nodular opacities on arterial phase
meckel’s on Meckel’s scan
-feeding artery (vitelline): extension beyond mesenteric border, no side branches, cork screw at terminal portion
“provacative angiography”
Provocative mesenteric angiography is the use of thrombolytic, vasodilating, and anticoagulation medications to elicit active bleeding from a
source that may have recently ceased
hemorrhaging
nitro 100-200 mcg or tPA 4mg
IR rx options for gi bleed
- microcoils- precise and can see them. Inab to advance micro-cash peripherally is mcc fx
- PVA particles (300-500µm) - flow directed. Less control
- EtOH for lower GI (bowel necrosis)
role of vasopressin in GI bleed
- vasoconstrictor. High re-bleed rates
- no superselection
- non-occlusive mesenteric ischemia (NOMI)
when to not use vasopressin
- large artery
- dual blood supply
- sev CAD, HTN, dysrhythmia
- s/p embolotherapy rx (risk bowel infarct)
purpose of post embo angiography
- collateral flow
ex: SMA run to look at inferior pancreaticoduodenal s/p GDA embo
which part of bowel has highest risk bowel infarct s/p embo?
after lig of Trietz (extensive collaterals in UGIB)
Techniques for abscess drainage
1) trocar: spinal needle & cath adj
2) seldinger-needle–> wire –> dilate –> cath
drain size for abscess drainage
- 6-8F-clear fluid
- 8-10F-thin pus
- 10-12F-thick pus
- 12+F-v complex/debris/odorous
why shouldn’t you 3way a drain?
reduce function
steps for abscess drainage
- decompress bladder
- abx first
- aspirate prior to leaving drain
next step: can’t advance drain into abscess
hydrophilic coated
flushing vs irrigation
-flushing-tube
irrigation-cavity
risk of aggressive irrigation
bacteremia. Limit volume to less than size of cavity
next step: irrigate w/ 20 cc, only get 5 back
-stop
next step: abscess drainage cath no longer draining.
1) confirm loc, kinkage
2) flush/clear obstr w/ guidewire
3) exchange-bigger size
mature tract
1 wk
remove drainage cath
- <10cc/d
- collection resolved by img
- no fistula
persistent fever s/p abscess drainage
- not draining
- addition abscess
- more img
next step: drainage of abscess spikes
- fistula
- img w/ fluoro
routes for pelvic abscess drainage
- most abscesses are dependent
- shortest, avoid VAN, dependent (pst, lat), don’t contaminate
- transabd
- transgluteal
- endoluminal- transvag, transrectal (least painful)
what to watch out for in transabd approach
inf epigastric
transgluteal approach
avoid: sciatic, gluteal a’s
- through sacrospinous lig, medial, inf to piriformis
disadvantages of transgluteal approach
- VAN injry
- catheter kinkage
- radiation
adv/disadv endluminal drains
- faster drainage
- less stable
transvag drains
- lithotomy position
- 12F (-)
- nevern <14 yo
transrectal drainage
for pre-sacral
*prep w/ cleansing enema
transgluteal vs transrectal drainage caths
- size-will pt poop it out before it drains
- safety of transgluteal route
diverticular abscess drain
> 2cm
- 10F+
- water seal if gas
risk of bx/aspiration echinococcal cysts
anaphylaxis
hepatic abscess drainage
controversial
don’t cross pleura
renal abscess-causes, mx
- asc inf, hematogenous
- <3-5cm-IV abx
- US guided aspirate/drain: >3-5cm, syx, not responding to iv abx
- urine leak: PCN
- well-tolerated, low complication rate, only relative CI is bleeding risk
perinephric absess
perforation of renal abscess into retroperitoneal space
mx urinoma
drained if persistent
perirenal lymphocele vs urinoma
-aspirate and check Cr
personal lymphocele mx
- recurr (makes aspiration difficult)
- sclerose cavity
pancreatic fluid collection drainage-indications
- infected
- ME
- never if un-infected
when pancreatic fluid colls drainage progress from drain to sx
if <75%/10 d. “video assisted retroperitoneal debridement”
pancreatic cutaneous fistula
compl of pancr drain
- clear fluid–> amylase+
- ocreotide (synthetic somatostatin), prolonged drainage
pancreatic pseudocyst drainage
- transperitoneal (avoids going through stomach twice).
- can’t avoid stomach or known duct communication (ie: needs drain for awhile)-transgastric (drains into stomach)
mx pancreatic pseudocyst communicates with duct
- somatostatin to slow down
- transgastric approach (drains into stomach)
- 6-8 wks drain
PCN indications
- obstr
- diversion (leak, fistula, refractory hemorrhagic cystitis)
- dx or therapeutic access-whitaker test, PCNL, stricture dilation/stent
absolute CI to PCN
- coagulopathy
- approach would cross colon, spleen, liver
- K <7
ideal route PCN
- elevate targeted side
- lower pole (PTX)
- pstlat 30˚ (brodel’s avascular zone), less angled
- enter 10 cm from midline (not beyond pst axillary line-risk colon). too medial=paraspinal
- parenchyma –> CS (otherwise, urine leak)
- medial –> lateral (avoid aorta/ivc, spine)
sticking a dilated vs non dilated collecting system
- dilated: single stick. US guided stick. Fluoro for wire, dilation, tube plcmt
- non-dilated: double stick. US guided stick, opacify. Fluoro for 2nd stick, etc
- whole thing under CT also okay
PCN on a transplant
- anterolaateral calyx
- mid/upper pole
- enter lat to transplant (avoid peritoneum)
PCNL-which pole, risks?
upper pole access
-tube/hold bigger, (+) risk bleed
PCN catheter maintenance
-change q2-3mo
encrusted tube
-hydrophilic wire along side of tube (ie: same tract) to maintain access
when/how do you kill ureters
- fistula, urine leak, intractable hemorrhagic cystitis
- sandwich w/ big coils, small in middle
indications nephroureteral stent
- long term drainage
- ureteral stricture (malignant MCC)
- injury
- calc undergoing lithotripsy
when to place anterograde NUS
- PCN in place
- retrograde failed
who should not get NUS
-no functional bladder
safety PCN
ensures functioning double J PCN
-cap –> bring back after 24-48 hrs –> if not obstructed, pull safety
suprapubic cystostomy-location
- midline just above pubic symphysis at junction of mid/lower 3rds ant bladder wall
- –avoids inf epigastric
- low stick: avoid peritoneum and bowel
- junction-avoid trigone (which will cause spasm)
ideal foley size for long term drainage
16F
CI to suprapubic cystostomy
- many sx (Scarring)
- obesity
- coagulopathy
- inab to distend bladder
- inab to displace overlying small bowel
indications renal bx
- cancer
- failure
alternative to standard renal bx in setting high risk bleed
transjugular
types of renal bx
1) non focal
2) focal
non focal renal bx-approach (position, location), complication rate, expected complication
- prone or targeted kidney up
- lower pole cortex (maximize glomeruli)
- low complication rate (small AV fistula’s and PAs common but spon’t resolve)
- some hematuria expected
focal renal bx-risk of seeding, position, what to avoid, what to aim for, what to send if concern for lymphoma
risk of seeding < 0.01%
- lat decub, lesion side DOWN (limits resp motion, bowel interposition)
- don’t cross renal sinus
- solid pt
- send for flow cytometery if lymphoma likely
why is ASA held for 5?
half life=8-10d
-normal marrow will replenish 30-50% platelets w/I 4 d of withholding
indications renal RFA
- RCCs
- AML
- AVM
- superficial lesions (avoid scarring CS). Pyeloperfusion techniques (cold D5W irrigating the ureter) can be done to protect
renal cryoablation
-lesions close to CS
img appearance recurr/residual dx s/p renal RFA
1) increased size s/p 1-2 mo (if <3cm, larger should NOT grow)
2) nod/cresc enh
3) new or enlarging T2+
renal arteriography projection
LAO
-“non selective” to assess number of arteries feeding
mx atherosclerosis at renal ostium
- mx-1st line
- angio + stent
mx FMD-pressure gradient, when to stent, when to sx, meds
- P gradient distal renal/aorta < 0.9, 10%.
- angio (no stent). upgrade until P gradient gone
- stent if complication-dissection, rupture
- sx-arterial bifurcation, complex aneurysm
- mx: ASA 75-100mg qd, ace=in/arb
- walnuts
risks and ppx mx of renal angioplasty
- thrombosis (heparin during procedure. ASA day before and qd/6 mo
- spasm-ccb
next step: arterial trauma from nephrostomy tube plcmt
remove tube over wire, check again
mx renal aneurysms
- small segmental-coil
- main renal-stent
complications chest tube
- ptx=mc
- reexpansion pulm edema
- bronchopleural fistula-air in pleur-eval chamber
choice of chest tube drainage cath size
- empyema: 12-14F inpatient, 10F outpatient
- malignant eff: 14F inpatient, 15.5 pleurx outpatient
lung tumor rfa-when, compl, adv
- 1.5-5.2 cm diameter
- PTX=mc complc
- reserves pulm function
what makes you think cancer after lung RFA
-nodular inch >10 mm central enh -growth of RFA zone after 3 mo, (6 mo=definite) -(+) metabolic act s/p 2 mo -residual act centrally
lung bx-where to avoid
- lower zone (resp motion)
- lingula (cardiac motion)
- vess >5mm
- fissures (PTX)
shock wave injury
vessels injured just lateral and distal to tip of bx gun
how to reduce risk of PTX post bx
- enter lung 90˚ to pleural surface
- avoid interlobular fissure
- puncture side down after procedure
- no talking/deep breathing fo 2 hrs
- anti-tussive/reschedule if cougher
“non-specific lung core bx results”
-repeat bx
when to place a chest tube after causing a PTX after biopsy
- ptx >2cm
- ptx enlarging
- pt short of breath
- aspirated >650 cc air
pigtail placement after causing ptx s/p bx
- 6-10F catheter (larger if fluid)
- triangle of safety–above 5th intercostal space, mid ax line (thinned m)
- heimlich valve-ambulatory
- remove s/p 1-2 d
next step: water seal chamber not fluctuating with resp or coughing
- lung fully expanded OR tube clogged
- cxr
next step: air bubbles in water seal chamber
- expected after initial insertion w/ resolving PTX
- new or persistent=problem
- CXR, check bandage, bronchopleural fistula
cause of subq emphysema
side holes not all in pleural space
indications pulmonary ateriography
- dx/rx PE
- pulm AVM
pulm angiography procedure
- grollman catheter=preshaped 7F
- RV, turn 180˚, adv into outflow tract
- measure P before injecting contrast (may want to reduce contrast burden)
pulm angiography relative Ci
- pulm HTN w/ RHP >70/20. Use low osmolar agent and inject into R or L PA
- LBBB-ppx pacing
next step: heart dysrhythmia during pulm angiograpy
reposition catheter/wire
mx massive pe (ie: hypoTN)
- thrombolysis
- thromboaspiration
- mechanical clot fragmentation
- stent
mc bronchial vascular variation
-intercostobronchial trunk on right and two bronchial arteries on L
where do most bronchial arteries arise?
T5-T6
mx rasmussen aneurysm
-coils (exception to rule of not using coils on bronchial a’s)
where does adamkiewicz org?
L pst intercostal a (btw T9-12)
-5% from R bronchus
which is emergent?: acute vs chronic SVC occlusion
-emergent vs not (collaterals)
mx mal vs nonmal causes SVC syndrome
- mal: lyse –> angioplasty –> stent
- non mal: angioplasty –> stent if P gradient still present, ie: collateral v’s remain
- no self-expanding stents-will migrate
- watch pericardium, ext to bottom part of svc
which fibroids have poor and good resp to embo
- degenerated: poor
- cellular: :)
-small > large
submucosal > intramural > serosal > cervical (diff bs)
mx: intracavitary fibroids < 3cm
GYN hystero resection. IR if fail
mx: large serosal fibroid, pt wants to be pregn, no hx of prior myomectomy
GYN for myomectomy
mx pedunculated serosal fibroid
GYN for resection
mx broad lig fibroid
-don’t do well w/ UAE and technically challenging to operate on
what to do in setting of gonadotropic releasing mx
-stop for 3 mo (shrink uterine a’s)
compls UAE
- premature meno 5%
- dvt/pe 5%
- post embo syndrome
embo material in UAE
- particles (500-700 µm or 700-900)
- pp hem/vag bleed: gel foam, glue
UAE for adenomyosis
- smaller particles
- good for syx relief
- recur 50% ~2yrs
what’s embolized in setting UAE
BL uterine a’s
ideal time for hysterosalpingogram
proliferative phase (7-14d)-endom thinnest
FP hystero
- sedative, narcotic, tubal spasm
- air bubble (FP filling defect)
- intravasation-contrast flows into venous or lymphatic system bc you pushed too hard (or obstruction).
Fallopian tube recanalization-options
- prox/interstitial-endoscope OR fluoro guided wire
- distal-sx
steps for fluoro guided fallopian tube recanalization
- follicular/proliferative phase
- repeat HSG-confirm tube still clogged
- selective salpingography. hydrophilic 0.035 or 0.018 wire
- repeat hsg
HSG CI
pregn. recent uterine or tubal pregn.
active pelvic inf
indications for varicocele rx
1) infertility
2) testicular atrophy
3) pain
drainage testicles
-papiniform plexus/spermatic venous plexus –> internal spermatic v at femoral head –> IVC (if R), left renal (if L)
causes of varicocele
1) right angle entry of v
2) nutcracker (compression L renal v btw SMA and aorta)
3) obstruction
mx varicocele
enter renal v, check for reflux
-get in goal v, embolism (foam) close to varicocele, drop coils on way out (amplatzer or occlusion device)
lymphangiogram
- 0.5 cc methylene blue dye btw toes BL –> 30 mins –> cannulate 27 or 30 g lymphangiography needle
- inject lipiodol (only 20 mL otherwise risk oil pneumonitis)
- spot film until see cisternal chili (sac at bottom of thoracic duct)
- puncture cc, select thoracic duct, emb w/ coil
risk of peritonitis with HSG
1%
indications vertebroplasty
- acute to subacute fx w/ pain refractory mx
- unstable fx w/ ass risk if further collapse occ
CI to vertebroplasty
- fx ass w/ spinal canal compression
- pain improving
risk vertebroplasty
- new fx 25%
- cement embo to lungs
- local neuro complication 5%
standing waves
angiographic phenomenon resulting in ringed layering of contrast. symmetric, evenly spaced.
-FMD: irregular, asymm
oblique views in IR
defined by side of image intensifier (not dir of x ray beam)
- RAO: II on R ant of pt (not an LPO)
- LAO: II on L ant of pt
durant’s maneuver
left lateral decubitus + head down positioning (trendelenburg)
-in setting of air embo
how needle will look when tilting table toward head or feet:
head: superficial needle looks shorter, deep needle looks longer
feet: vice versa
half life tpa
2-10 min
ideal placement for piccs
basilic > brachial > cephalic (Alphabetical order)
absolute CI to line placement
- cellulitis, allergy
- Rel CI: coagulopathy, CV/occlusion, PICC in CKD or CRF
how many AV fistula’s fail to mature
30-50%
AV fistula “mature” rule of 6
*Vein big enough/arterialized for high flow P > 600 mL/min >0.6 cm diam < 0.6 cm depth 6 wks
preferred AV fistula sites
1) radial a –> cephalic v; preferred. (-) maturation; stenosis @ juxtaanastomotic segm
2) brachial a –> brachiocephalic v- 2nd preferred; (+) DASS; precludes future forearm first
3) brachial a –> brachiobasilic (if cephalic v unsuitable; tech diff (2 stage sz), (+) DASS, stenosis @ prox swing segm)
suitable anatomy for AVF
a > 2mm diam, v > 2.5 mm
when would you use AV graft over fistula
-if unsuitable anatomy for AVF
where are av grafts placed?
forearm > UE > groin
mcc fistula non arterialization
arterial inflow stenosis (doesn’t allow dilation & arterialization of fistula)
pulsatile, ø thrill vs weak pulse, weak thrill vs pulseless
high access recirculation at dialysis
venous outflow obstruction
arterial inflow stenosis
thrombosis
venous outflow stenosis
outflow vs inflow stenosis
- outflow: aneurysmal dil of access, arm/face swelling, prolonged bleeding, tense/pulsatile access, (+) VP
- inflow: flat/nonvisualize/easily collapsible fistula; difficult cannulation; no thrill or bruit
indications of av fistula repair
1) stenosis=MC
2) failed maturation
3) DASS (Grades I, ii)
4) thrombus
pre-procedural doppler evaluation
1) feeding a-low res
2) arterial anastomosis-N to be turbulent. PSV > 400 cm/s or >3x feeding a=stenosis
3) v OF-pulsatile, low res; 2-3x adj v=stenosis
4) central v
when to use abx in ir procedures
1) clean contaminated-respiratory, alimentary, GU tract
2) purposeful infarction of tissue
3) sometimes/often new devices (stent grafts, vertebral augmentation.
standard doses for moderate sedation. Reversal agents?
-midazolam 1g + fentanyl 50µg
Naloxone is the opiate reversal, with a typical first doe of 0.2mg, which can be repeated. Flumazenil reverses benzodiazepine with a typical first dose of 0.2mg.
standard injection rate for main PA in pulmonary angiography
25cc/s for 50 total
“high risk” procedure regarding coagulopathy
-new holes in vascular organs, ie: kidney, liver
“NPO”
clears for 2 hrs
-solids for 6hrs
how much epinephrine do you give in anaphylaxis
0.3 mL of 1mg/mL IM OR 2mL of 1mg/10mL (0.1mg/mL) IV (slow flush)
reason to call on-call attending overnight
- uncontrolled bleeding
- infected obstructed viscus
- PIE
appearance of various causes GI bleed on angiography
- pool of contrast=active extrav
- ill defined enhancing lesion= tumor blush
- tuft of vessels & draining vein= angiodysplasia/AVM
wedge hepatic pressure=
trans-sinusoidal portal venous pressure
definition of portal HTN
wedge hepatic P - RA P = > 6mmHg
significance of elevated free hepatic P and R atrial P (>5 mmHg)
hepatic veno-occlusive dx
best mx of iliac and visceral stenoses?
-balloon expandable stents
basic injection rates and volumes
aortogram: 20 for 30 abdominal aorta: 20 for 20 IVC: 20 for 30 mesenteric a: 5 for 25 renal artery: 5 for 15 distal artery: 3 for 12
dilating force/hoop stress (T) equation
Diameter x Pressure
nominal pressure
pressure whereby balloon reaches stated diameter
-non compliant balloons by definition do not dilate significantly beyond their stated diameter (even at pressures much greater than nominal.)
common injection rates: thoracic aorta, abdominal aorta, abdominal aortic bifurcation/iliac arteries, femoropopliteal arteries, celiac/SMA, main pulmonary artery, selective right or left pulmonary artery, IVC
- thoracic aorta: 20 mL/s
- abdominal aorta: 15 mL/s
- abdominal aortic bifurcation/iliac a’s: 5-10 mL/s
- femoropopliteal a’s: 4-6 mL/s
- celeac/SMA: 4-6 mL/s
- main pulmonary a: 20 mL/s
- selective R or L pulmonary a: 10 mL/s
- IVC: 10-20 mL/s
when would prolonged power injection be carried out?
- opacify large vascular bed
- detect small or peripheral bleed
- study venous outflow of organ
empiric vs weight-based heparin dose
- empiric: 5000u –> 1000u after each additional hour
- weight-based: 50-100 u/kg
ACT goal for therapeutic anticoagulation
1.5-2.5x baseline (if no baseline available, use ACT >200s)
What size wire will an 18g and 21g needle accept?
- 21g: 0.018” to 0.021” wire
- 18g: .035” to 0.038” wire
When and how much albumin to give during paracentesis
6-8 g/L if >5L fluid taken off
life expectancy for which external drains may be left in place
<3 mo
standing waves vs FMD
standing wave - long segm and symm/uniform
implication of CO2 low viscosity
- rapid diffusion-elucidate subtle findings (small hemorrhages, endoleaks, collateral vessels)
- retrograde opacify vascular structure across capillary or sinusoidal bed
course of uterine a
- internal iliac anterior division –> course medially
- initial descending –> transverse –> ascending
when are embolic protection devices used?
carotid and lower extremity arteries
moderate sedation agents
- opiate (pain)-fentanyl 25-100 mcg
- benzo (anxiolytic)-midazolam 0.5-2mg
- short acting ==> 30-60 min procedures
best view to evaluate arch and great vessels
LAO (patient is RPO)
RAO is good for brachiocephalic bifurcation
projections for common iliac and common femoral arterial bifurcations
CL oblique
IL oblique
vertebral augmentation
- vertebroplasty-percutaneous injection of cement (polymathy methacrylate) into vertebral body
- kyphoplasty-adjunctive balloon inflation in VB for additional cement injection –> restore height
CI to vertebral augmentation
bony retropulsion from fracture
course of thoracic duct
cisterna chyli at thoracolumbar junction (just right of ml) –> ascend thorax just left of ml –> L IJV (where subclavian joins)
agents used in thoracic duct embo
- coils
- nBCA glue: lipiodol mixture
MC indication thoracic duct embo
trauma or iatrogenic duct injury
mx thoracic duct embo
- conservative (low fat diet, TPN, ocreotide infusion, tube)
- percut embo
- sx
ideal arteriotomy site for LE work
middle 1/3 femoral head
middle colic a course
-ext ~cm then branch in a T configuration –> R & L branches along transverse colon –> anastomose w/ R an L colic arteries –> marginal a of colon
when is vasopressin used?
GI bleed (vasoconstrictor)
hepatic a vs portal v vs hepatic v vs bile ducts
- hepatic a: small caliber, tortuous, branch peripherally. Pulsatile forward flow. +/- cystic a
- portal v: straighter, larger; slow con’t flow. +/- periumbilical v/varix
- hepatic v: flow toward IVC, RA
- bd: slow hepatofugal flow toward hilum; non-dev (left lobe) branches fill later) –> bowel.
How long do temporary embolic agents last?
days-weeks
temporary embolic agents and examples of use
- autologous clot-percutaneous biopsy tract
- gelatin-traumatic hem, precut bx tract
- thrombin-percut int of PA
permanent embolic agents and ex of use
- metallic coils (pushable, detachable), vascular plugs (covered or uncovered): traumatic vessel injury, GIB, aneurysm/PA occlusion, AVF, pulm AVM embo, sm/large vess occlusion, PV embo
- particles-benign and mal tumor embo, bronchial and GI hem, PV embo, partial splenic embo
- liquid (nBCA glue, onyx): vascular malform, TD emo, PV emo, small vess hem (GI/bronchia/inf epigastric), partial splenic embo, aneurysm endoleak embo
