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GI GI BLEEDS & ISCHEMIABLEEDS & ISCHEMIAMDCT MDCT -- In the hands of a In the hands of a radiologistradiologist

Bertil Leidner, Bertil Leidner, MDMD

Part I

GI BleedsGI Bleeds

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Acute Bleed - Clincial Workup

Stabilize the patient» stabilization of BP/pulse

» restoration of volume before diagnostics

» Most complications from hypo-perfusion

Upper GI – endoscopy

L GI MDCT / CTA Lower GI – MDCT / CTA

Sensitivity & specificity CTA

Problem of intermittent bleeding

Metaanalys 1995-2009

9 studies, 198 patients

CTA acute GI bleeding» Ref standard: endoskopy, angio or surgery

Sens 89%, specif 85%

My comment: » Better performance w MDCT 64 ch+

Wu et al, World J Gastroenterol, Aug 2010

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Bleeding rate for detection

RBC scintigraphy 0 1 0 2 ml/min RBC scintigraphy 0.1- 0.2 ml/min

Convent mesent angio 0.5 ml/min

CTA 0.2-0.3 ml/min» iv high dose high injection rate» iv – high dose, high injection rate

» 0.2 ml vid peak aortic enhancement >200 HU

Kuhle et al Radiology 2003 228:743-752 (CTA -swine model)

Subacute/chronic

Surgical/clinical» Endoscopy

– Gastroscopy

– Capsule endoscopy

– Colonoscopy

Radiologygy» RBC scintigraphy

» MDCT / CTA

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70 y old woman

3 months earlier 3 months earlier» Small bowel GIST tumor with intussuception

(invagination)

Abd pain, dark vomiting, diarrhea with freshblood

Clinically unstable

Native – non-contrast

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(Late) Arterial

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What phases? Earlier contrast; confusing details

»native Vasculature – aneurysm – interventional roadmap

» angiographic phase (late arterial)

Active bleed» late arterial

» venous

» + Late phase– enhances detection of slow bleed

– gives information of bleeding pace

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Protocol

Scan protocol (64 ch)» Native series (50% of rad dose; 5/5mm)» Arterial phase - 25 sec after 160 HU in

aorta abd» Venous phase + 25 sec» Late phase + 60-120 sec» Late phase + 60 120 sec

Thin slice recon» Base for MIP, VRT

Oral Contrast

No oral contrast» Time loss with oral C» Positive contrast obscures contrast

extravasation» Negative contrast (water) may dilute the

extravasation…

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Iv contrast

0.75 g I/ kg bodyweight

High concentration 400/370/350 mg I/ ml

Warm ! (värmeskåp + injektorvärmare!)

Max 6 – 8 ml/sec – 25 sec injection time» Pink (rosa) 1.0/1.1 mm - 20 G = OK

» Green (grön) 1.2/1.3 mm 18 G

Connection line (special for power injector)» No other devices (ingen 3-vägskran)

» Multiuse systems – ”backventil” must be ”high flow”

Abdominal trauma

Woman Woman» Fell over child car seat

Severe abd pain

Signs of peritonitis

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Sliding MIP 10/3 + interactive

Roadmap

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SOS / FFF

Hypovolemic signs Hypovolemic signs» IVC ↓, aorta ↓

– (in the scenario of ongoing or recent bleed)

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SOS?

SOS? Change in patient management?

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When to use MDCT/CTA ?Broad spectrum diagnostics!

Complicated Whipple w portal resection Complicated Whipple w portal resection» Postop day 2 – liver enzymes up

Referral: US liver and portal cirkulation

Examination: CTA

Findings – cf art/venous phase

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How to optimizeradiological care/MDCT ?

Define logistics of how to handle the acute Define logistics of how to handle the acutesituation of a bleeding patient» Together with your surgeons!

Establish MDCT / CTA-protocols» Use liberally in critical patientsy p

Critical patients with relative contraindications» Be prepared – don´t hesitate

Hesitations:Radiation & Contrast

R di ti Radiation»Young & Pregnancy

iv- contrast

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Radiation Cost vs Benefit

Old Old vs young

Risk comparison -- CT abd 10 mSv» 2 months work travel Stockholm-Gävle (before

highway north of Uppsala)

» 500 cigarettesg

» 5 months construction work

What happens if you miss a serious diagnosis?

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Pregnancy & radiation

< 10 days < 10 days» Any damage abortion

week 3-8» border dose: 100-200 mGy

week 8-15week 8 15» border dose 200 mGy

Trauma CT Huddinge» 25 mGy

CT & pregnancy

Save the mother» Save the child

Emergency & Trauma = OK» Threshold damage 100 mGy

» 4x whole body scan

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Structure a pregnancy protocol

Lower the dose for native series Lower the dose for native series » From 50% to 25% of standard dose

Omit late scan

Use 100 kV for arterial + venous series» Set a dose reduction by 50%» Set a dose reduction by 50%

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Questions/problems iv contrast

Breast feeding OK Breast feeding – OK

Allergy» Premedicate

» If severe - anestesiologist present

Renal function & iv contrast

Renal insuffiency» Calculate GFR

» Omnivis – re: achieve a diagnostic examination

» kV adjustment– 80 -100 kV

Cost-benefit analysis Cost-benefit analysis

» severity of clinical situation

Don´t save the kidneys and loose the patient

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Example: Female 59 y o

Renal insuffiency (P-creatinine >200) Renal insuffiency (P creatinine >200) 2 h sudden onset of severe abd pain with

peritonitis. Free air? Perforated ulcer? Pancreatitis? Scan protocol?

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Now what?

Angio? Angio?

CT-angio?

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Angio – only vessel accessible - SMA

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CTA vs Angio

Unstable patient?» CT-angio?

» Angio?

CT » During preparation time for angio

» more sensitive for bleed

» roadmap for intervention– Saves intervention time

» CT + intervention More iv contrast (?)

If negative MDCT?

If 1st MDCT is of high quality If 1st MDCT is of high quality» New MDCT if the clinical situation motivates

If 1st MDCT is of low quality» Conventional angio

» Or if possible –new MDCT of high qualityp g q y

After negative MDCT + negative conv angio» Keep catheter indwelling

» MDCT with arterial injection

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Intermittent bleeding - provocation Nonlocalised lower gastrointestinal bleeding:

provocative bleeding studies with intraarterial tPAprovocative bleeding studies with intraarterial tPA, heparin and tolazoline.

J Vasc Interv Radiol 2001;12:1273e7. Ryan JM, Key SM, Dumbleton SA, et al. Koval G, Benner KG, Rosch J, et al. Aggressive angiographic diagnosis in acute

lower gastrointestinal haemorrhage. Dig Dis Sci 1987;32:248-53

If clinically needed» 3 neg operations, 6 neg angios, > 150 units of

blood

MDCT patient preparation/provocation

Stabilized with adequate BP» BP > 100; pulse< 100

– If not treat w fluid volume to the patient

– Cf permissive hypotension in trauma care

Consider provocation (w surgeon) in extreme casescases» If neg MDCT, neg angio, serious clinical problem

» Aggressive volume substitution

» With indwelling cath - anticoagulation; vasodilatation

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Take home message

CTA detects slower bleed rates than conventionalangioangio» 0.2-0.3 ml/min vs 0.5 ml/min

Cooperate with your surgeons

» Together create a routine for CTA use in criticalcases

» Agree on handling of patients with relative contraindications

Be present @ the examination

Do not hesitate – remember you are a doctor

P IIPart II

GI ischemia

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Acute Mesenteric Ischemia

Arterial

V Venous » SMV thrombosis

» SBO – small bowel obstruction

No occlusion of SMA/SMV» commonly decreased cardiac output hypoperfusion

» both the SMA and IMA (small+large bowel) + parenchym organs

» mesenteric vessels patent + intestinal wall enhancement

Acute Ischemia

Treatment » largely surgical?

» emergent need for revascularization combined with an assessment of bowel viability

Reginelli et al.: Mesenteric ischemia: the importance of differential diagnosis forReginelli et al.: Mesenteric ischemia: the importance of differential diagnosis for the surgeon. BMC Surgery 2013 13(Suppl 2):S51.

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Chronic Ischemia

ArterialArterial» severe atherosclerotic disease; older

patients

» at least 2 of the major mesenteric arteries

» develops over a long period collaterals are presentare present

Treatment» Largely non-surgical

MDCT / CTA in ischemia

Gold standard Gold standard

Sensitivity 82% - 96%; specificity 94%

Reginelli et al.: Mesenteric ischemia: the importance of differential diagnosis for the surgeon. BMC Surgery 2013 13(Suppl 2):S51.

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Case: Female 66 y o

Diarrhea vomiting + abd pain 2 days Diarrhea, vomiting + abd pain 2 days

KOL, longstanding Mb Crohn

Exam without iv contrast» due to non defined ”allergy towards» due to non-defined allergy towards

contrast media”

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No free air. Dilated small bowelloops with suspicion of distal obstruction.

O d i t & di t l Oedema in mesentary & distal ileal wall – inflammmatoryreaction??

Air in intrahepatic bilary ducts or in peripheral portal branches but not in central porta. No air in bowel

llwalls

Status post ERCP/papillotomy?

Follow-thru exam started……

12 h later2nd exam + iv contrast

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2nd radiology report (iv contrast +)

Suspicion of thrombus in proximal a mes Suspicion of thrombus in proximal a mes sup & coeliac trunc.

Air in portal vein + intestinal wall

Patchy hepatic necrosis

Acute laparotomy reveals no pulsation in Acute laparotomy reveals no pulsation in these arteries & extensive tissuenecrosis

No further actions. Patient dies in ICU

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Discussion

Limits of non contrast exam Limits of non-contrast exam» Diagnostic hesitation, delay!

Make it easy to diagnose» = iv contrast !

» Even the least experienced radiologistp gshould be able to diagnose correctly

Ischemia

85 year old man 85 year old man

Advanced cardiovascular disease, claudicatio

5 h severe abd pain w acute onset, no peritonitisp

Lactate up 6.8

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SMA– ocklusion

Consequenses

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Now what?

Diagnosis» SMA ocklusion, intestinal ischemia/necrosis?

» @ 6.5 h after onset

How to optimize handling of this type of patients?» Intervention suite?» Intervention suite?

» OR?

» Hybrid room?

Female 57 y - MS

2 days abdominal pain vomiting peritoneal status 2 days abdominal pain, vomiting, peritoneal status

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CT @ 24 h

Necrotic intestine

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MDCT protocol in ischemia

Native Native

Late arterial phase

Venous phase as in bleeding protocol.» No late series

Why do we need native scan?

Native Native

+ iv contrast

Non contrastintestinal wall with high density

(Venous oedemahaemorrage)

Images from Yann Geffroy et al: CT Detection of Ischemia

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Hesitation to use iv contrast

Value of the hypotheticaldiagnosis (frågeställning)diagnosis (frågeställning)

to choose iv contrast or not?

Clincial case :non-contrast exam possible?

53 y o man Cholecytistis? Abdominal pain 2

days, right flank

Fever 38.4, LPK 16.4

Tender dorsal over kidney + right flank +

Pyelitis? Appendicitis? Rt testis?

y gpain in the scrotum

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Aortic ocklusion

Case discussion: iv contrast complication

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32 year old female;4 h post partum

Abdominal pain Abdominal pain

Tachycardia, low blood pressure

P-krea 150

DIC injury to liver + kidneys

CT PROTOCOL CT PROTOCOL» 160 ml Visipaque 320 @ 6 ml/s

+ pending intervention w contrast

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Follow up

Dialysis 6 weeks» Anuria 2 weeks

» Polyuria phase

Rescanned twice w iv contrast» abscess?

Judged to regain renal & liver function Judged to regain renal & liver function

2 years later – limited renal impairment» Creatinine 120

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Discussion

Amount of iv contrast high Amount of iv contrast high» Lower dose vs find the bleeding source

Several instances of iv contrast use

Lifesaving procedures

Take home messages

Identify the critical patient

Use iv contrast if the patient is critically ill» Even if there are relative contraindications

Optimize the use of iv contrast» Lower the kVp

» High flow rate

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Take home messages

Diagnosis of the critically ill patient g y pis the goal !! Use Radiation & Contrast

Be a Doctor

In struggle to save livesTEAMWORK ......

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Thank you for your

attention!

bertil.leidner.se

attention!