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Intestinal Ischemia
Michele Young, MD
Chief GI Phoenix VA Hospital
Banner/VA GI Fellowship
Program Director
Outline
 Types
 Anatomy
 Pathophysiology
 Acute Mesenteric Ischemia
 Mesenteric Vein Thrombosis
 Focal Segmental Ischemia
 Colon Ischemia
 Chronic Mesenteric Ischemia
 Vasculitides
Types
TYPE FREQUENCY (%)
Colon ischemia 75
Acute mesenteric ischemia 25
Focal segmental ischemia <5
Chronic mesenteric ischemia <5
Anatomy  Celiac Axis
 Supplies stomach, duodenum, pancreas, and
liver
 Three branches: left gastric, common hepatic,
splenic
 Common hepatic: gastroduodenal, right
gastroepiploic, anterior superior
pancreaticoduodenal
 Splenic: pancreatic and left gastroepiploic
Anatomy  Celiac Axis
Anatomy  Superior Mesenteric Artery (SMA)
 Anterior and posterior inferior
pancreaticoduodenal
 Middle colic
 Right colic
 Ileocolic
Anatomy - SMA
Anatomy  Inferior Mesenteric Artery (IMA)
 Left colic
 Sigmoid branches
 Superior rectal
 Supply distal transverse to proximal rectum
 Distal rectum: internal iliac
Anatomy - IMA
Pathophysiology
 Bowel can tolerate 75% reduction of blood flow
and oxygen consumption for 12 hours
 Collaterals open immediately
 After hours, vasoconstriction reduces collateral
flow (NOMI)
 Hypoxia, reperfusion injury
 ROS by xanthine oxidase
 Microvascular injury by PMNs
Acute Mesenteric Ischemia
CAUSE FREQUENCY (%)
SMA embolus 50
Nonocclusive mesenteric ischemia 25
SMA thrombosis 10
Mesenteric venous thrombosis 10
Focal segmental ischemia 5
Clinical Features
 Acute abdominal pain in patient with CV risks
 Rapid and forceful bowel evacuation (SMAE)
 Pain out of proportion to exam
 Some more indolent (MVT)
 Unexplained abdominal distention (sign of
infarction) or GI bleeding (NOMI)
 Physical findings worsen with progressive loss of
bowel viability
 Infarction: 70-90% mortality
Diagnosis
 Labs
 75% have WBC > 15
 50% have metabolic acidosis
 Plain films
 Poorly sensitive (30%) and nonspecific
 Formless loops of small intestine
 Ileus, thumbprinting, pneumatosis
 Portal or mesenteric vascular gas
 CT
 Colon dilatation
 Bowel wall thickening
 Lack of enhancement of arterial vasculature
 Ascites
 CT angiography
 Better evaluation of vessels
 Selective mesenteric angiography
 Gold standard
 Prompt laparotomy if angiography not available
Case presentation rectus Sheath hematoma.ppt
Case presentation rectus Sheath hematoma.ppt
Case presentation rectus Sheath hematoma.ppt
Case presentation rectus Sheath hematoma.ppt
Case presentation rectus Sheath hematoma.ppt
Portal Gas
Case presentation rectus Sheath hematoma.ppt
Treatment
 General
 Resuscitation, Broad-spectrum antibiotics
 Superior Mesenteric Artery Embolus
 Cardiac origin
 Major: proximal to ileocolic
 Intra-arterial papaverine
 Surgical revascularization
 Minor and no peritoneal signs
 Intra-arterial papaverine (or thrombolytics)
 Anticoagulation
SMA Embolus
Pre and post treatment
Treatment
 Nonocclusive Mesenteric Ischemia
 Vasoconstriction from preceding cardiovascular
event
 Angiography
 Narrowing of SMA branch origins
 Irregularities in intestinal branches
 Spasm of arcades
 Impaired filling of intramural vessels
 SMA infusion of papaverine for 24 hours
 Surgery if peritoneal signs are present
NOMI
Pre and post treatment
Treatment
 Acute Superior Mesenteric Artery Thrombosis
 Severe atherosclerotic narrowing
 Often superimposed on chronic mesenteric
ischemia
 Demonstrated on aortography
 Management same as SMA embolism
Mesenteric Vein Thrombosis
 Age: mid-60s to 70s
 20% mortality
 Manifest as colon ischemia, acute mesenteric
ischemia, or focal segmental ischemia
 Causes
 Arterial hypertension
 Neoplasms
 Coagulation disorders
 Estrogen
Mesenteric Vein Thrombosis
 Acute
 Pain out of proportion to exam, n/v
 Lower GI bleeding suggests infarction
 Diagnosis
 CT is study of choice (finds >90%)
 Mesenteric arteriography
 Slow or absent filling of mesenteric veins
 Failure of arterial arcades to empty
 Prolonged blush in involved segment
 Treatment
 Incidental: up to six months of anticoagulation (AC)
 Peritonitis: surgery, papaverine, post-op heparin
 No peritoneal signs: heparin followed by 3-6 mos AC
Mesenteric Vein Thrombosis
 Subacute
 Abdominal pain for weeks to months but no
infarction
 Chronic
 Asymptomatic
 May develop GI bleeding from varices
 Treatment: control bleeding
Focal Segmental Ischemia
 Involves small bowel
 Causes
 Atheromatous emboli
 Strangulated hernias
 Immune complex disorders
 Trauma
 Segmental venous thrombosis
 Radiation therapy
 Oral contraceptives
 Usually adequate collaterals to prevent infarction
 Presentation: enteritis, stricture, acute abdomen
 Chronic can resemble Crohn's
Focal Segmental Ischemia
 Radiologic studies
 Smooth tapered stricture
 Abrupt change to normal distally
 Dilated proximally
 Treatment: resection
Colon Ischemia
TYPE FREQUENCY (%)*
Reversible colopathy and transient colitis >50
Transient colitis 10
Chronic ulcerating colitis 20
Stricture 10
Gangrene 15
Fulminant universal colitis <5
Colon Ischemia
 Most common form of intestinal ischemia
 7.2 cases per 100,000 person-years
 Female predilection
 Most > 60 years old
 Young pt: vasculitis, coagulation disorders,
cocaine, medications
 Right colon ischemia
 May have small intestinal ischemia
Medications
 Penicillins
 Alkaloid and taxanes
 Constipation-Inducing Agents
 Pseudoephedrine
 Diuretics
 Oral contraceptive pills
 Amphetamines (R sided)
 Cocaine (L sided)
 Kayexelate
 Magnesium citrate
 Sodium phosphate
 Bisacodyl
 Glycerin enemas
 NSAIDs
 Sumatriptan
 Alosetron
Pathology
 Mild: mucosal and submucosal hemorrhage and
edema
 More severe: ulcerations, crypt abscesses,
pseudopolyps, pseudomembranes, iron-laden
macrophages, submucosal fibrosis (stricture)
 Most severe: transmural infarction
Clinical Features
 Sudden cramping
 Mild left lower quadrant pain
 Urgent desire to defecate
 Hematochezia within 24 hours
 Location:
 Sigmoid 23%
 Descending-to-sigmoid 11%
 Cecum-to-hepatic flexure 8% (worse prognosis)
 Descending 8%
 Pancolonic 7%
Diagnosis
 CT scan
 If nonspecific, colonoscopy within 48 hours
 Unprepped, low air
 Colon single-stripe sign
 Line of erythema with erosion or ulceration along
the longitudinal axis of the colon
 Milder course
Colonoscopy
Case presentation rectus Sheath hematoma.ppt
Case presentation rectus Sheath hematoma.ppt
Case presentation rectus Sheath hematoma.ppt
Case presentation rectus Sheath hematoma.ppt
Treatment
 NPO, IVF, antibiotics
 EKG, Holter, echo
 Colonic infarction
 Laparotomy and resection
 Serosa can be misleading
 Segmental Ulcerating Colitis
 Recurrent fevers and sepsis
 Continuing or recurrent bloody diarrhea
 Persistent or chronic diarrhea with protein-losing
colopathy
 Treat by resection
Treatment
 Ischemic Stricture
 Dilation or resection
 Universal Fulminant Colitis
 Colectomy with ileostomy
 Isolated Ischemia of the Right Colon
 Check CTA for concurrent AMI
 Carcinoma/Obstructive Lesions (<5%)
 Lesion distal, increased intracolonic pressure proximal
 Irritable Bowel Syndrome
 Colon ischemia 3.4 to 3.9x more common
 ?Hypersensitivity of the colonic vasculature
 Complicating Aortic Surgery
 Up to 7% of surgeries (60% for ruptured aneurysm)
 Colonoscopy within 2-3 days if high risk
 Ex: ruptured aneurysm, prolonged cross-clamping time, post-op diarrhea
Chronic Mesenteric Ischemia
 Intestinal angina
 Mesenteric atherosclerosis
 Pain from small bowel ischemia
 Blood stolen to meet increased gastric demand
from food
Clinical Features
 Gradual cramping discomfort within 30 minutes
of eating, resolves over hours
 Fear of eating, weight loss
 Nonhealing antral ulcers without H. pylori
 1/3 to 遜: cardiac, cerebral, peripheral vascular
disease
 Exam
 Abdomen soft and nontender
 Bruit common but nonspecific
Diagnosis
 Gastric tonometry exercise testing (GET)
 NG tube and arterial line
 Patient on PPI
 Obtain gastric juice and arterial blood fasting, during,
after exercise
 Measure gastric-arterial PCO2 gradients
 Increase after exercise indicates ischemia
 Combine with duplex U/S
 Angiography
 Should show occlusion of 2 splanchnic arteries
 Does not make diagnosis in itself
Treatment
 Revascularization
 Need occlusive involvement of 2 major arteries
 Surgical if healthy
 Otherwise percutaneous +/- stent

More Related Content

Case presentation rectus Sheath hematoma.ppt

  • 1. Intestinal Ischemia Michele Young, MD Chief GI Phoenix VA Hospital Banner/VA GI Fellowship Program Director
  • 2. Outline Types Anatomy Pathophysiology Acute Mesenteric Ischemia Mesenteric Vein Thrombosis Focal Segmental Ischemia Colon Ischemia Chronic Mesenteric Ischemia Vasculitides
  • 3. Types TYPE FREQUENCY (%) Colon ischemia 75 Acute mesenteric ischemia 25 Focal segmental ischemia <5 Chronic mesenteric ischemia <5
  • 4. Anatomy Celiac Axis Supplies stomach, duodenum, pancreas, and liver Three branches: left gastric, common hepatic, splenic Common hepatic: gastroduodenal, right gastroepiploic, anterior superior pancreaticoduodenal Splenic: pancreatic and left gastroepiploic
  • 6. Anatomy Superior Mesenteric Artery (SMA) Anterior and posterior inferior pancreaticoduodenal Middle colic Right colic Ileocolic
  • 8. Anatomy Inferior Mesenteric Artery (IMA) Left colic Sigmoid branches Superior rectal Supply distal transverse to proximal rectum Distal rectum: internal iliac
  • 10. Pathophysiology Bowel can tolerate 75% reduction of blood flow and oxygen consumption for 12 hours Collaterals open immediately After hours, vasoconstriction reduces collateral flow (NOMI) Hypoxia, reperfusion injury ROS by xanthine oxidase Microvascular injury by PMNs
  • 11. Acute Mesenteric Ischemia CAUSE FREQUENCY (%) SMA embolus 50 Nonocclusive mesenteric ischemia 25 SMA thrombosis 10 Mesenteric venous thrombosis 10 Focal segmental ischemia 5
  • 12. Clinical Features Acute abdominal pain in patient with CV risks Rapid and forceful bowel evacuation (SMAE) Pain out of proportion to exam Some more indolent (MVT) Unexplained abdominal distention (sign of infarction) or GI bleeding (NOMI) Physical findings worsen with progressive loss of bowel viability Infarction: 70-90% mortality
  • 13. Diagnosis Labs 75% have WBC > 15 50% have metabolic acidosis Plain films Poorly sensitive (30%) and nonspecific Formless loops of small intestine Ileus, thumbprinting, pneumatosis Portal or mesenteric vascular gas CT Colon dilatation Bowel wall thickening Lack of enhancement of arterial vasculature Ascites CT angiography Better evaluation of vessels Selective mesenteric angiography Gold standard Prompt laparotomy if angiography not available
  • 21. Treatment General Resuscitation, Broad-spectrum antibiotics Superior Mesenteric Artery Embolus Cardiac origin Major: proximal to ileocolic Intra-arterial papaverine Surgical revascularization Minor and no peritoneal signs Intra-arterial papaverine (or thrombolytics) Anticoagulation
  • 22. SMA Embolus Pre and post treatment
  • 23. Treatment Nonocclusive Mesenteric Ischemia Vasoconstriction from preceding cardiovascular event Angiography Narrowing of SMA branch origins Irregularities in intestinal branches Spasm of arcades Impaired filling of intramural vessels SMA infusion of papaverine for 24 hours Surgery if peritoneal signs are present
  • 24. NOMI Pre and post treatment
  • 25. Treatment Acute Superior Mesenteric Artery Thrombosis Severe atherosclerotic narrowing Often superimposed on chronic mesenteric ischemia Demonstrated on aortography Management same as SMA embolism
  • 26. Mesenteric Vein Thrombosis Age: mid-60s to 70s 20% mortality Manifest as colon ischemia, acute mesenteric ischemia, or focal segmental ischemia Causes Arterial hypertension Neoplasms Coagulation disorders Estrogen
  • 27. Mesenteric Vein Thrombosis Acute Pain out of proportion to exam, n/v Lower GI bleeding suggests infarction Diagnosis CT is study of choice (finds >90%) Mesenteric arteriography Slow or absent filling of mesenteric veins Failure of arterial arcades to empty Prolonged blush in involved segment Treatment Incidental: up to six months of anticoagulation (AC) Peritonitis: surgery, papaverine, post-op heparin No peritoneal signs: heparin followed by 3-6 mos AC
  • 28. Mesenteric Vein Thrombosis Subacute Abdominal pain for weeks to months but no infarction Chronic Asymptomatic May develop GI bleeding from varices Treatment: control bleeding
  • 29. Focal Segmental Ischemia Involves small bowel Causes Atheromatous emboli Strangulated hernias Immune complex disorders Trauma Segmental venous thrombosis Radiation therapy Oral contraceptives Usually adequate collaterals to prevent infarction Presentation: enteritis, stricture, acute abdomen Chronic can resemble Crohn's
  • 30. Focal Segmental Ischemia Radiologic studies Smooth tapered stricture Abrupt change to normal distally Dilated proximally Treatment: resection
  • 31. Colon Ischemia TYPE FREQUENCY (%)* Reversible colopathy and transient colitis >50 Transient colitis 10 Chronic ulcerating colitis 20 Stricture 10 Gangrene 15 Fulminant universal colitis <5
  • 32. Colon Ischemia Most common form of intestinal ischemia 7.2 cases per 100,000 person-years Female predilection Most > 60 years old Young pt: vasculitis, coagulation disorders, cocaine, medications Right colon ischemia May have small intestinal ischemia
  • 33. Medications Penicillins Alkaloid and taxanes Constipation-Inducing Agents Pseudoephedrine Diuretics Oral contraceptive pills Amphetamines (R sided) Cocaine (L sided) Kayexelate Magnesium citrate Sodium phosphate Bisacodyl Glycerin enemas NSAIDs Sumatriptan Alosetron
  • 34. Pathology Mild: mucosal and submucosal hemorrhage and edema More severe: ulcerations, crypt abscesses, pseudopolyps, pseudomembranes, iron-laden macrophages, submucosal fibrosis (stricture) Most severe: transmural infarction
  • 35. Clinical Features Sudden cramping Mild left lower quadrant pain Urgent desire to defecate Hematochezia within 24 hours Location: Sigmoid 23% Descending-to-sigmoid 11% Cecum-to-hepatic flexure 8% (worse prognosis) Descending 8% Pancolonic 7%
  • 36. Diagnosis CT scan If nonspecific, colonoscopy within 48 hours Unprepped, low air Colon single-stripe sign Line of erythema with erosion or ulceration along the longitudinal axis of the colon Milder course
  • 42. Treatment NPO, IVF, antibiotics EKG, Holter, echo Colonic infarction Laparotomy and resection Serosa can be misleading Segmental Ulcerating Colitis Recurrent fevers and sepsis Continuing or recurrent bloody diarrhea Persistent or chronic diarrhea with protein-losing colopathy Treat by resection
  • 43. Treatment Ischemic Stricture Dilation or resection Universal Fulminant Colitis Colectomy with ileostomy Isolated Ischemia of the Right Colon Check CTA for concurrent AMI Carcinoma/Obstructive Lesions (<5%) Lesion distal, increased intracolonic pressure proximal Irritable Bowel Syndrome Colon ischemia 3.4 to 3.9x more common ?Hypersensitivity of the colonic vasculature Complicating Aortic Surgery Up to 7% of surgeries (60% for ruptured aneurysm) Colonoscopy within 2-3 days if high risk Ex: ruptured aneurysm, prolonged cross-clamping time, post-op diarrhea
  • 44. Chronic Mesenteric Ischemia Intestinal angina Mesenteric atherosclerosis Pain from small bowel ischemia Blood stolen to meet increased gastric demand from food
  • 45. Clinical Features Gradual cramping discomfort within 30 minutes of eating, resolves over hours Fear of eating, weight loss Nonhealing antral ulcers without H. pylori 1/3 to 遜: cardiac, cerebral, peripheral vascular disease Exam Abdomen soft and nontender Bruit common but nonspecific
  • 46. Diagnosis Gastric tonometry exercise testing (GET) NG tube and arterial line Patient on PPI Obtain gastric juice and arterial blood fasting, during, after exercise Measure gastric-arterial PCO2 gradients Increase after exercise indicates ischemia Combine with duplex U/S Angiography Should show occlusion of 2 splanchnic arteries Does not make diagnosis in itself
  • 47. Treatment Revascularization Need occlusive involvement of 2 major arteries Surgical if healthy Otherwise percutaneous +/- stent

Editor's Notes

  • #5: AIPD, anterior inferior pancreaticoduodenal artery; ASPD, anterior superior pancreaticoduodenal artery; CP, caudal pancreatic artery; DP, dorsal pancreatic artery; GD, gastroduodenal artery; H, common hepatic artery; LG, left gastric artery; PIPD, posterior inferior pancreaticoduodenal artery; PM, pancreata magna; RGE, right gastroepiploic artery; S, splenic artery; TP, transverse pancreatic artery.
  • #7: AIPD, anterior inferior pancreaticoduodenal artery; COL, colic branches; IL, ileal branches; IC, ileocolic artery; JEJ, jejunal branches; MC, middle colic artery; PIPD, posterior inferior pancreaticoduodenal artery; RC, right colic artery.
  • #9: AOR, arc of Riolan; ASC, ascending branch of the left colic artery; CA, central artery; DSC, descending branch of the left colic artery; LMC, left branch of middle colic artery; MA, marginal artery; MC, middle colic artery; RMC, right branch of middle colic artery; S, sigmoid branches; SR, superior rectal artery