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Introduction and Objectives | Provocative Mesenteric Angiography
Introduction and Objectives | Provocative Mesenteric Angiography
2017angiographyAVIRcliniccompletedfloridainternshipinterventionalmayomedicalmesentericprovocativeservestechnologist
Provocative | Provocative Mesenteric Angiography
Provocative | Provocative Mesenteric Angiography
2017AVIRbleedchaptercliniciansdesirefull videosexual
GI Bleeding and Causes of Occult GI Bleeding | Provocative Mesenteric Angiography
GI Bleeding and Causes of Occult GI Bleeding | Provocative Mesenteric Angiography
2017angioangiosAVIRbleedingchapterctasdysplasiaendoscopyepisodicfull videohemodynamichemorrhageindeterminateintermittentneoplasmneoplasmspatientpatientspediatricradiologic
Provocative Angiography and History | Provocative Mesenteric Angiography
Provocative Angiography and History | Provocative Mesenteric Angiography
2017aggregationangiographyanticoagulatedAVIRchapterextravasationfibrinolysisfull videohemorrhagehemostasisintravascularlocalizepharmacopharmacologictpavasoconstriction
Contraindications | Provocative Mesenteric Angiography
Contraindications | Provocative Mesenteric Angiography
2017absoluteAVIRchapterconservativelycontraindicationcontraindicationsfull videoHypertensionintestinalintracranialneoplasmspatientportalpostpartumsurgerytiastpavaricealvarices
Preprocedural Considerations and Complications  | Provocative Mesenteric Angiography
Preprocedural Considerations and Complications | Provocative Mesenteric Angiography
2017anesthesiaangiogramAVIRendoscopiesextremityhematomashemorrhageinstitutionlowermesentericmetabolizedmoderatesurgicalsystemicsystemicallytpavenousworkup
Protocols | Provocative Mesenteric Angiography
Protocols | Provocative Mesenteric Angiography
2017angioAVIRbaselinebleedcatheterizechapterdiagnosticdosedosesextravasationfull videoheparininjectionlowerpatientperformprotocolquadrantsymptomaticterritorytpavesselvesselsvolumes
Summary  | Provocative Mesenteric Angiography
Summary | Provocative Mesenteric Angiography
2017angiosAVIRchapterdosingfull videointerventionalistsmultidisciplinaryvasodilators
Transcript

So our next talk...sorry... is an evolving technologies panel. Our first speaker Dr. David Sella completed his medical education from the University of South Florida College of Medicine. He then completed his residency with the Mayo Clinic and his vascular and interventional

fellowship at the Medical College of Wisconsin. He's currently located at Mayo Clinic in Jacksonville Florida where he serves as an assistant professor. As an advocate for technologists' education he serves as the medical advisor for the

institution's technologist internship program. Today he'll be speaking to us about provocative mesenteric angiography for occult bleeding. Please welcome him to the podium. Ok.

Okay thank you very much. We're going to talk about provocative mesenteric angiography today. And no financial

So first of all definitions. Whenever we do one of these cases in our lab there's

always a lot of discussion about the word provocative. So there's two definitions in the dictionary. One causing a very strong reaction or anger especially deliberately like when you're trying to induce the GI bleed. The second

definition intended to arouse sexual desire or interest has nothing to do with this procedure. Alright so we want...we're not fifty shades of grey...we want to provoke a bleed not sexual desire interest. Just to

get that out of the way. So why would we try to make somebody bleed when we often spend our nights and weekends stopping bleeding. And the answer is frustration most importantly on the behalf of patient but also referring

clinicians in the IR team in general.

Because it turns out that GI bleeding is a pretty extensive work up there's a lot of causes of it and it can be a diagnostic and management dilemma when recurrent and of an indeterminate origin

and you can't see it by endoscopy you can't see it by any radiologic studies. And it turns out these patients present as a continuum. So they can range all the way from chronic intermittent bleeding which is characterized as really slow kind of

sporadic in nature and this is often too slow to detect by imaging studies. Or it can be severe episodic life-threatening hemorrhage and oftentimes these cases stop before you can even get the patient to imaging. So what happens is these are of

intermittent nature they are of variable severity patients have changes in hemodynamic status and you get into this cycle of patients having multiple CTAs tagged scans angios upper/lower double balloon capsule... any type of endoscopy

that you can think of and they end up going from institution to institution. And this puts significant financial and health risk to the patient going through all these procedures. And they get extremely frustrated and sometimes this

is the only thing that people have to offer them and it's just they're miserable. So there's a lot of causes of occult GI bleeding especially in the middle...the mid gut and I'm not going to read all this to you but the point of

this is you want to know your patient population. So if you have primarily patients that are in the pediatric younger age group less than 40 and the over 40 age group which is the majority of my patients you want to

think about neoplasms and angio- dysplasias and things like that as the most common causes. And so you basically just need to know this is my population. Right I live in Florida. Everybody's retired. They come down and have margaritas at five o'clock

everyday. And you know it's always a neoplasm or some sort of angio dysplasia in these patients. So what

exactly is the definition of this. It's when we combine catheter directed delivery of the pharmacologic agent

such as TPA with intermittent angiography and we want to increase the yield or chance of extravasation and not compromise the patient safety or efficacy. And it turns out that this has been around for quite awhile. It was

originally termed pharmaco angiography in '82. And was used in the setting of problematic lower GI bleeding. And the thought is this you have vaso... these patients have vasoconstriction they get platelet aggregation creation of this

soft intravascular plug and they get transit hemostasis. So they bleed stops. But in reality they walk a very fine line between hemostasis and bleeding. So if you induce a vasodilatation. You anticoagulated them you give them

localized fibrinolysis you can react... reactivate the hemorrhage and localize the abnormality or the abnormal vessel. So

contraindications briefly it varies from patient to patient and institution to institution. One person's

absolute contraindication for TPA maybe somebody else's relative. But in generally these are patients we play a little bit conservatively because we're taking somebody from the stable to an unstable

state potentially. So TIAs CVAs within six months intracranial neoplasms craniotomies mobile left heart thombus intestinal surgery within three months these are all absolute contraindications. And then relative things like recent

major surgery uncontrolled hypertension pregnancy or the postpartum period severe cerebral vascular disease and portal hypertension. You know portal hypertension mean that if you have a

patient that has varices and you are giving them a bunch of TPA and you induce a variceal bleeding then you're gonna have to salvage with a TIPS or some sort of variceal embolisation. So

pre-procedural you want to talk about...

patients you want to look at the renal function. They're gonna get a lot of angiograms it's a large volume of contrast you want to make sure they're hydrated and they resuscitated if they come in from a...from an acute

bleed. What is their surgical candidacy. There's a wide range of surgical backup that's required from institution to institution so it can range anywhere from hey I'm doing this provocative angiogram today

so just in case there's a bleed that I can't control to all the way to oh we have an OR on standby just in case there's something that you can't you know control. And you know probably somewhere in the middle like many things is the proper

way to do this but it varies from institution to institution. And sedation wise most of these we do with moderate sedation. You can look at general anesthesia because patients have to...it can be time-consuming if they have low

back pain or are heavy narcotic users you want them to be able to you know hold still for angios. But the vast majority with moderate sedation. And then what is the workup been thus far. I always like to have a high-quality CTA

or CT enterography to make sure there's not some structural lesion that's been missed because oftentimes this patient will show up with outside records they have endoscopies elsewhere and you really want to cover the basics before you get into the

state. And what happens to them afterwards they can get a hemorrhage requiring transfusion hypertension puncture site hematomas things that all common to catheterization. The biggest fear is uncontrollable GI CNS or

non-target bleeding. And the one thing protecting us a little bit is TPA is it's primarily metabolized through the liver so if you're giving your TPA directly into the mesenteric vessels like the SMA or the IMA you're gonna get

very high first pass metabolism of the TPA. So you're systemically lower constant or... your systemic concentrations are actually much lower than when you get it...say you're doing a lower extremity case or venous case and

so that's why we can get away I think with a lot of higher doses. So protocols

there's a lot of institutional variation. We haven't really settled on any one thing that's great. There's been some groups that have tried to sort of

standardized this for research processes. But in reality it's like drip a little TPA and here and there and you talk to different people and they do different doses and it's really sort of a cookbook scenario or making it up as they go

along. So this is really the most well described protocol. It's from the Duke group. And what they do is they do basic celiac....there are three vessel angiography at these rates you're looking at like a

five for 20 or 7 for 21 injection for the celiac and SMA territory and then the IMA little dose may be a few hand injections based on the patients. In reality most of these patients have undergone some sort of diagnostic

imaging or endoscopy or something to help determine the distribution of currents...of concern. So are you looking at the SMA are you looking at the IMA territory that's a big part of it. So that's where you want to focus your efforts on.

So if you have a positive study whether it it be endo or CTA or a tagged red cell you want to catheterize that vessel territory after your baseline angiography. If you don't have any clue where it's coming from you just start in the SMA and perform your

baseline angio. And then you give systemic heparin through an IV so target ACT at 250. Usually start with about 5000 units such as in this protocol. You give intra-arterial nitroglycerine so into your SMA territory about 200

mics and then 4 milligrams of TPA. You wait five minutes and then you perform an angiogram right and it's usually negative. And then you step it up and you go a little bit higher with the TPA maybe 12

milligrams this time around you can vasodilate the patient again with some more nitro. Wait five minutes and perform another one. And you sort of escalate up and then this protocol they peek out at 24 milligrams of TPA on

the third run and you can see there's some differences on the slide if you're in the IMA you're getting lower volumes overall and the big part of waiting in between is if you're reconstituting small volumes of TPA this actually takes

awhile to add of small bottles to reconstitute all this. If you're not getting any results after going all the way up to three rounds after 24 you can consider terminating the procedure you want to do a repeat injection of your

vessels to make sure you're not missing something in another territory and then you can go to the IMA territory and sort of repeat this at the IMA doses and then terminate the exam after that. So this is a case of the guy that has been

bouncing in and out of the hospital for a few months he had two or three angios at our institution. There's endoscopic clips down in the right lower quadrant and so we have some idea where it's going through this he

had come hemodynamically unstable and by the time we got to him to angio for the second...or the third time this was...it had stopped. So we did give him some medication so we started with a low dose with four milligrams 5000 units Heparin

and 200 micrograms of nitro. And this is the boring part of the procedure so you sort of wander around and talk amongst yourselves and you can draw some pictures on the back table with your magic marker. But you don't want to get

complacent because what happens is these people...I've had happen several times where they get all the sudden very symptomatic they feel their GI bleed in usually I'm wandering around and looking at stuff on the wall a tech throws themselves

on top of the patient to keep them from rolling off the table and things like that because....these...they become very symptomatic if you do induce a bleed sometimes. So we have our baseline angio this is after the TPA and there's a bleed in the right

lower quadrant near the clips. And the fellow catheterizes it and embolizes it. So this protocol was used in publishing couple of years ago and they had a diagnostic extravasation rate of thirty percent. This is another case

where ... it's up there.. it's up in here basically there's a bleed. So this patient has an LVAD in they're very sick they've been down to the angio suite several times. And just to speak of the

intermittent nature of this by the time we get out to catheterize the actual vessel it's it had stopped even after the provocation and there's a lot of changes in the vessels here worrying about you know mesenteric ischemia in

this patients we elected not to really do anything embolic wise. And he actually stabilized. You know other people to split dose continuous infusion. So this is a bilateral groin approach with catheterization of the SMA and IMA. We

generally run kind of a standard infusion rate like you would run in a lower extremity. I haven't had a particularly a lot of of work of success with that protocol. The point of this is the range of diagnostic extravasation in

these studies they're all very small numbers 9 18 16 10. And that the range of success is all the way from thirty percent to ninety percent depending on the agents and and things that you look at. So post-procedure mostly people

hate staying in the hospital because they've been in the hospital so much especially if their a chronic slow kind. If they do have a believe we keep them overnight with H/Hs and follow them like a routine lower GI bleed.

So in summary there's multiple causes of fore mid and hind gut bleeding which can cause a diagnostic dilemma for clinicians. The decision to proceed with provocative angios is a multidisciplinary effort with the

consensus of you know an MDT team so it's not for every patient that comes in that has a negative angiogram. And the reported success rates and protocols are variable. So we don't know the optimum type dosing the combination of different types of

anti- coagulants and vasodilators that are most successful is really unknown. So this is there are some groups that are looking at this and animal models and things like that. But this is something

that's been causing a problem for interventionalists and for patients more importantly for a long time. Thank you.

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