Ischemic Bowel Disease-Causes-Signs-Symptoms-Treatment

Ischemic Bowel Disease:
Ischemia means a decrease in blood supply (blood flow) to an organ, tissue or part of the body. For example, cerebral ischemia means a decrease in blood supply to the brain.
Maintenance of adequate blood flow is very important for correct and functioning and survival of an organ.
Adequate blood supply provides oxygen and nutrients to the tissue and also removes waste materials from the site of formation. Inadequate blood flow or ischemia compromises the function of the organ because the organ is not getting enough nutrients and accumulation of toxic wastes destroy the function of the organ. If blood supply continues to decrease and ischemia is not correct, the organ may die.
Maintenance of adequate blood flow is important. Because in some cases there is normal arterial blood supply but there is an obstruction in venous return. Therefore, blood won't flow through the vessels and this also results in ischemia.

Ischemic bowel disease is the disease of bowel (intestine) or pathological changes in intestines that results from ischemia (decreased blood supply).

Intestinal Blood Supply:


Arterial Blood Supply:

- Celiac artery –

-  the first portion of the duodenum
- Superior mesenteric artery –

-  the remainder of the small bowel and the large bowel up to the splenic flexure

l Inferior mesenteric artery –

-  the remainder of the large bowel and part of the rectum

l Branches of the internal iliac artery

- distal rectum


Venous Drainage
l The hepatic portal circulation carries venous blood from the gastrointestinal organs and spleen to the liver.
l Eventually, blood leaves the sinusoids of the liver through the hepatic veins which drain into the inferior vena cava.
Predisposing Factors:

l Age (older than 50)
l More frequent in women
l High blood pressure (hypertension).
l Diabetes
l High cholesterol
l Smoking
l History of heart attack
l Stroke


Causes:
        vascular occlusion (Arterial)

Atherosclerosis

l Aortic aneurysm.

l Embolization of cardiac vegetations or aortic atheromas.

vascular occlusion (Venous)

lHypercoagulable states.

lInvasive neoplasms.

lCirrhosis.

lTrauma

lAbdominal masses compressing portal drainage.

Intestinal hypoperfusion.

lCardiac failure.

lShock.

lDehydration.

lSystemic vasculitis

Pathogenesis:

lIschemic lesion may be restricted to the small or large intestine or may affect both, depending on the particular vessel or vessels involved.

lSeverity of ischemic damage also depends on time frame of occlusion (acute or chronic) and degree of vascular compromise.

lThe severity of the injury ranges from:

lTransmural infarction of the gut, involving all visceral layers, to

lMural infarction of the mucosa and submucosa , sparing the muscular wall, to

lMucosal infarction, Just mucosa is involved
severity of infarction depends upon the level of blood supply compromise.

Signs And Symptoms:

lNausea

lVomiting

lFatigue

lTransient bloody Diarrhea

lLow-grade fever

lAbdominal pain, tenderness

   or cramping 

lMinimal abdominal distention

lHypoactive bowel sound

Treatment
Treatment depends on the cause of ischemic bowel disease.

Treatment options for mild ischemic bowel disease include:
Anticoagulant medications:
Heparin
Warfarin (Coumadin)
Angioplasty for bowel ischemia
To open the artery that supplies the intestine

Treatment options for life-threatening ischemic bowel disease include:
Papaverine injection for bowel ischemia
Dilates the arteries supplying blood to the intestine
Surgery for bowel ischemia:
To open the artery that supplies the intestine

References:

* Robins Basic Pathology

* Freemd.com
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