Disorders of the

Gastrointestinal System

Orlando Regional Medical Center

2008

Intestinal Obstructions

Intestinal Obstruction

• Blockage of intestinal tract that inhibits passage of fluid, gas, feces

• Caused by

– mechanical obstruction (strangulated hernia, adhesion, cancer, volvulus, intussusception)

– neurogenic obstruction (paralytic ileus, uremia, electrolyte imbalance(low K), spinal cord lesion)

– Vascular disease (occlusion of superior mesentery vessels)

Intestinal Obstructions• Paralytic Ileus or “silent bowel” is most

often seen after abdominal surgery & anesthesia

• bowel activity is < due to lack of neural stimuli (“functional”)

• this can lead to “mechanical” obstruction due to accumulation of feces

• Hernias: a loop of bowel protrudes through abdominal wall

• inguinal canal, umbilicus, or incisional scar tissue • caused by heavy lifting, straining, or coughing

Sigmoid Volvulus

• Sigmoid Volvulus (twisting): usually seen in the older individual with a history of straining at stool – Symptoms: abdominal distention, nausea, vomiting,

and crampy abdominal pain; check history of flatus and BMs

– Abrupt onset is indicative of an acute obstruction– Sudden onset due to “torsion or hernia?”

• A chronic history of constipation is related to a dx of diverticulitis or carcinoma

• Obstipation (no flatus or BM) & loss of weight = carcinoma

Sigmoid Volvulus

Intussusception

• only 5-15 % occurrence in adults

• s/s colicky abd pain, nausea, vomit,

diarrhea, constipation

• diagnosed by barium enema, CT scan

• treated via surgical resection

Intussusception

Small Bowel Obstruction

“Never let the sun rise or set on

a small bowel obstruction.”

(surgical saying)

Small Bowel Obstruction

Causes of SBO:Adhesions (post-surgical, post-inflammatory)

Incarcerated hernia

Malignancy: usually metastatic

Intussusception

Volvulus

Gallstone ileus

Parasites

Foreign body

Small Bowel ObstructionCauses of small bowel obstruction include:• Adhesions from previous abdominal surgery • Hernias containing bowel • Crohn's disease causing adhesions or inflammatory strictures • Neoplasms benign or malignant • Intussusception in children • Volvulus • Superior mesenteric artery syndrome a compression of the

duodenum by the superior mesenteric artery and the abdominal aorta

• Ischemic strictures • Foreign bodies (e.g. gallstones in gallstone ileus, swallowed

objects) • Intestinal atresia • Parasites

Small Bowel Obstruction

Signs & Symptoms of Small Bowel Obstruction:

• Abdominal pain

• Vomiting

• Elimination problems (Diarrhea)

• Bloating

Small Bowel Obstruction

The essentials:

* Common, may or may not require surgery

* Emergent, if bowel is strangulated (to OR)

* KUB not necessarily diagnostic-Shows dilated loops, air-fluid levels

* CT very sensitive and specific-Better at transitional zone, cause of SBO

Small Bowel Obstruction

Large Bowel Obstruction

• A large bowel obstruction is an emergency condition that requires early & prompt surgical intervention

• Etiology: • infectious / inflammatory, neoplastic, or mechanical

pathology (colorectal cancer)

• Rotation or twisting of the cecum or sigmoid colon will cause abrupt onset of symptoms

• Immediate abdominal distention– Decreases the ability to absorb Fluids &

Electrolytes

Large Bowel Obstruction

Causes of large bowel obstruction include:

• Neoplasms

• Hernias

• Inflammatory bowel disease

• Colonic volvulus (sigmoid, caecal, transverse colon)

• Fecal impaction

• Colon atresia

• Benign strictures (Diverticular Disease)

Large Bowel Obstruction

Signs & Symptoms of Large Bowel Obstruction:

• Abdominal pain

• Vomiting (not common)

• Elimination problems (Constipation or Loose)

• Bloating

Large Bowel Obstruction

When to Operate?

• Incarcerated or strangulated hernia• Peritonitis• Pneumoperitoneum

• Suspected strangulation• Closed loop obstruction• Complete obstruction

• Virgin abdomen• LARGE bowel obstruction

Gastrointestinal Disorders

Diarrhea

• Causes of Diarrhea– Osmotic: the presence of nonabsorbable

substances in the intestine causing water to be drawn into the lumen by osmosis

• sorbitol-containing liquid medications; tube feedings

• lactose intolerance

– Secretory: excessive mucosal secretion of fluid & electrolytes

• related to: gastroenteritis (E. Coli), rotavirus, laxative abuse, hyponatremia, fecal impaction

Intestinal Ulcers

Peptic Ulcer Disease

• An inflammatory disorder causing deep erosion of stomach or duodenal mucosa by HCL & pepsin

• At risk: infection with H. pylori; > NSAIDS; > secretion of HCL as seen in Zollinger-Ellison syndrome

• Etiology: age, family hx– > mucolytic enzymes; may lead to pyloric obstruction,

bowel perforation and ultimately peritonitis

• Sx: hallmark sign = upper gastric pain– Emergency: hematemesis, melena, occult blood, shock

Peptic Ulcer Disease

• Treatment includes: – < ETOH intake – screen for H. pylori (C-urea breath test)

– frequent small meals – avoid calcium based antacids d/t > gastrin

release – H2 blockers (Tagamet & Zantac) – Insert NG tube for severe bleeding and gastric

lavage

Bowel Disorders

• Ulcerative Colitis– A disease that causes inflammation and

sores in the lining of the large intestine.

• Crohn’s Disease– A disease that causes inflammation in the

small intestine, but it may affect any part of the GI tract.

– Smoking, diet, and/or immune response to bacteria

Gastric Cancer

• Adenocarcinoma is the primary malignant neoplasm

– Etiology:chronic inflammation, dietary influences, genetic & environmental factors

• 8th leading cause of mortality r/t cancer in US

• Epidemiology: 55-60 year olds; 2 times greater incidence in men vs. women

• Risk factors: H. pylori, < socioeconomic class, consumption of pickled foods, improper food storage, radiation exposure

Colorectal Cancer• “Patients with long-standing ulcerative colitis

have been shown to be at increased risk of developing colorectal cancer” (Medscape, 1999)

• Involves a primary malignant tumor of the rectum or colon

• 2nd leading cause of cancer death in US

• > incidence in 50 year olds • > fat and poor fiber diet; > ETOH consumption;

cigarette smoking; obesity; sedentary life style

• Exact etiology unknown…> incidence with polyps

Colorectal Cancer• Symptoms:

– fecal occult blood or ulcerative lesions manifest as anemia or rectal bleeding

• distention, abdominal pain, vomiting, constipation

– metastatic disease: weight loss, anorexia, possible palpable mass

• Prevention: ASA may < risk; routine monitoring for guaic (+)

• Treatment: colostomy repair; permanent colostomy for rectal tumors

Gastrointestinal Bleeding

Terms of GI Bleeding• Hematemesis – vomiting of blood (or coffee ground

material) (indicates bleeding proximal to the Treitz)

• Melena – passage of black tarry stools > 50ml (indicates degradation of blood in the bowel)

• Hematochezia (rectal bleeding) – passage of red blood

• Occult Bleeding – bleeding that is not apparent to the patient and results from small amounts of blood

• Obscure Bleeding – occult or obvious but source not identified

Localization of GI Bleeding

• Hematemesis – always UGI source

• Melana – indicates that blood has been in GIT for extended periods

– Mostly UGI

– Small bowel

– Right colon (if bleeding relatively slow)

• Hematochezia – Mostly colon

– Massive UGI bleeding (not enough time for degradation)

GI Bleeding• Upper: includes the esophagus, stomach, duodenum

• peptic ulcer disease (PUD) or esophageal varices

• Lower: includes the jejunum, ileum, colon, rectum • colorectal cancer, polyps, hemorrhoids, IBD

• Manifestations: • hematemesis• bright red blood in the stool (“hematochezia”) • black,dark, tarry stools (“melena”) • “occult” bleeding (invisible blood in the stool)

• Treatment: find the underlying cause; fluid volume replacement; endoscopy or colonoscopy; medical and /or surgical therapy

Acute UGI Bleeding Mallory-Weiss Tear

• Mucosal laceration at the GEJ

• 10% of cases

• Typically follows retching but mostly on 1st vomit (75%)

• 90% stop bleeding spontaneously

• Endoscopic Therapy sometimes required

Acute UGI BleedingPortal Hypertension

• Sources of bleeding:– Esophageal varices– Gastric varices– Portal hypertensive gastropathy

• Urgent gastroscopy:– Sclerotherpay– Band ligation

• Somatostatin• Balloon tamponade (Sengstaken-Blackmore

tube)

Acute UGI BleedingDuodenal & Gastric Ulcer

• Most common etiology of UGI bleeding

• Duodenum>stomach

• Predisposing factors for bleeding:– NSAID’s

– Underlying medical conditions: IHD; cerebrovascular disease

– Ethanol, anticoagulant Therapy

– Hospitalization

Acute UGI BleedingDuodenal & Gastric Ulcer

• Predisposing factors for bleeding cont.:

– Gastric acid

– H. Pylori: Role in bleeding not certain but definitely, eradication prevents rebleeding

– Aspirin & NSAID’s:

Duodenal & Gastric Ulcer

UGI BleedingGastric Erosions

• NSAID’s

• Stress:– Serious trauma

– Extensive burns

– Major surgery

– Major illness (ICU)

– Major neurological disease (CVA, tumor, trauma)

• Alcohol abuse

UGI BleedingMalignancy

• Malignant:

– Esophageal cancer

– Gastric cancer or lymphoma

– Small intestinal lymphoma or cancer

• Benign:

– Leiomyoma

UGI Malignancy

Lower GI Bleeds

Four most common causes of LGI bleeds

• vascular ectasias

• colonic diverticuli

• neoplasm

• internal hemorrhoids

LGI bleeds - Other Causes

• solitary rectal ulcer syndrome (SRUS)

• colonic varicies• mesenteric vascular

insufficiency• ischemic colitis• Meckel’s diverticulum• small intestinal

ulceration• intussusception

• radiation-induced injury• diversion colitis• mesenteric venous

thrombosis• small bowel diverticuli

• Dieulafoy lesion• vasculitis• long-distance running• endometriosis

Acute Lower GI Bleeding

• Initial management – similar to acute upper GI bleeding

• Presentation: wide range of presentation:

– Mostly self-limiting bleeding that does not require hospitalization

– Rarely massive with hemorrhagic shock

Acute Lower GI BleedingDiverticulosis of the Colon

• Common cause (25%)

• Acute, painless, bright red, maroon or melena (depending on site)

• May compromise hemodynamics (elderly)

• Diagnosis: per exclusion

• Significant recurrence

• Treatment: most subside spontaneously, some need angiographic embolization or surgery

Acute Lower GI BleedingColonic AV Malformation

• Aka: Vascular Ectasias, Angiodysplasias, AV malformations

• They are:

– degenerative lesions of previously normal blood vessels located in the cecum and ascending colon

• They are not:

– telangiectasias, congenital defect, hemangiomas

Acute Lower GI BleedingVascular Ectasias

• the right colon is subjected to numerous

colonic distentions that cause intermittent

obstruction of the submucousal veins

outflow tract leading to their dilation

Vascular Ectasias - Treatment

• 90 % stop spontaneously• 80 % of the remainder stop after IV or intra-

arterial vasopressin• transcatheter embolization• laser• endoscopic sclerosis• heater probe• electrocoagulate• surgery

Acute Lower GI BleedingAngiodysplasia

• Presentation:– Acute (recurrent)– Chronic

– Occult

• Older pts (mainly>70)

• High association with CRF• Most – right colon

Acute Lower GI Bleeding Angiodysplasia

• Diagnosis:– Colonoscopy

– Angiography

• Treatment:– Electrocoagulation

– Injection

– LASER

– Surgery

Angiodysplasia

Acute Lower GI BleedingHemorrhoids

• Most common cause• Presentation:

– recurrent low-volume bright red blood on the paper or on stool

– Straining aggravates bleeding

– Rarely associated with anemia (acute or chronic)

• Never relate bleeding to hemorrhoids before exclusion of other lesions

Lower GI BleedingMesenteric Vascular OcclusionVascular insufficiency - occlusive vs. non

• 75 % from mesenteric a. emboli

• usu. elderly presenting as acute abd pain, concomitant heart disease, spontaneous GI bleed, pain out-of-proportion with the PE

• mortality 50 - 90 %

• diagnosed by arteriography

• treated by emergent ex lap

Acute Lower GI BleedingOther Causes

• Meckel’s diverticulum

• Infectious colitis: Shigella; Salmonella; campylobacter

• Radiation proctitis

• Ischemic colitis

• IBD – colitis (UC;CD)

Acute Lower GI Bleeding

Evaluation of source:• History:

– Age (tumors & diverticular disease more common in elderly pts; IBD more common in young)

– HIV (CMV colitis)– NSAID’s – Family or personal Hx of polyps or CRC– Change in bowel habits– Pain (in IBD, ischemic colitis…); Anal pain – Previous abdominal irradiation– Previous surgery (particularly vascular)– ASCVD (ischemic colitis)

Acute Lower GI Bleeding

• Diagnostic procedures:

– Colonoscopy

– Tagged RBC Scintigraphy – low predictive value

– Angiography + Embolization

– Surgery (rare)

• Effectiveness:

– Localization of bleeding site: : 57-72%

– Reduced operative mortality: : 9-14% vs.. 37-50%

Angiography

Transcatheter Embolization

• Initial control: 71 -100%

• Rebleed rate : 0-12%

• Ischemia: 0-21%

Occult bleeding

• Diagnosis:

– Imaging of the colon:• Colonoscopy

• DC barium enema

• CTC

– Gastroscopy

– Small bowel follow-through

– Video-capsule

GI Bleeding• Do Not Underestimate GI Bleeding

– Don’t assume anything

• Do Not Ignore Bright Red Bleeding– Monitor VS

– Don’t assume anything

• Do Not Overreact to GI Bleeding– Monitor VS

• Do Report GI Bleeding– Don’t assume anything

ReferencesFundamentals of Diagnostic Radiology, 2nd edition (1999). Brant, William E. & Helms, Clyde A., eds. Williams and Wilkins, Baltimore MD.

Delabrousse, E., Destrumelle N., Brunelle S., Clair C., Mantion G., Kastler B. (2003) CT of small bowel obstruction in adults. Abdominal Imaging 28(2): 257-266.

www.uptodate.com: Clinical manifestations and diagnosis of small bowel obstruction; Treatment of small bowel obstruction; Abdominal wall and groin hernias.

Hansen, M. (1998). Pathophysiology: Foundations of disease and clinical intervention. Philadelphia: Saunders.

http://www.medscape.com

Givens BA, Simmons SJ: Gastroenterology in Clinical Nursing. 4th ed. St. Louis, Mo: C.V. Mosby Co, 1984. 

Ripamonti C, Bruera E: Palliative management of malignant bowel obstruction. Int J Gynecol Cancer 12 (2): 135-43, 2002 Mar-Apr.  [PUBMED Abstract]

Potluri V, Zhukovsky DS: Recent advances in malignant bowel obstruction: an interface of old and new. Curr Pain Headache Rep 7 (4): 270-8, 2003.  [PUBMED Abstract]

Baron TH: Expandable metal stents for the treatment of cancerous obstruction of the gastrointestinal tract. N Engl J Med 344 (22): 1681-7, 2001. PUBMED Abstract]

Mercadante S: Assessment and management of mechanical bowel obstruction. In: Portenoy RK, Bruera E, eds.: Topics in Palliative Care. Volume 1. New York, NY: Oxford University Press, 1997, pp. 113-30. 

ReferencesGivens BA, Simmons SJ: Gastroenterology in Clinical Nursing. 4th ed. St. Louis, Mo: C.V. Mosby Co, 1984. 

Ripamonti C, Bruera E: Palliative management of malignant bowel obstruction. Int J Gynecol Cancer 12 (2): 135-43, 2002 Mar-Apr.  [PUBMED Abstract]

Potluri V, Zhukovsky DS: Recent advances in malignant bowel obstruction: an interface of old and new. Curr Pain Headache Rep 7 (4): 270-8, 2003.  [PUBMED Abstract]

Baron TH: Expandable metal stents for the treatment of cancerous obstruction of the gastrointestinal tract. N Engl J Med 344 (22): 1681-7, 2001. PUBMED Abstract]Mercadante S: Assessment and management of mechanical bowel obstruction. In: Portenoy RK, Bruera E, eds.: Topics in Palliative Care. Volume 1. New York, NY: Oxford University Press, 1997, pp. 113-30.