Pyloric Obstruction
- Narrowing of pylorus (junction between stomach and duodenum)
- Two forms…acquired or congenital
Infantile hypertrophic pyloric stenosis (IHPS) aka…Congenital pyloric stenosis
Congenital” narrowing of pylorus Signs/symptoms: • infant at 2-3 weeks begins to vomit for no apparent reason • “projectile vomiting” – several feet Frequency • infant disorder (3 per 1000 births) • Pathophysiology • Pyloric sphincter is hypertrophied Etiology: • not fully established • hormones to allergic reactions have been suggested as potential causes Treatment: • Surgery • Pyloromyotomy:
Adult/Acquired Pyloric Obstruction
- Usually caused by severe peptic ulcer or tumor in area
- Vague s/s of epigatric discomfort/fullness with eating that progresses to severe epigastric discomfort
- Gastric distention, nausea, progress to vomit and acute distress as obstruction develops over time
- Treatment: address cause of obstruction
Adhesion- Mechanical Obstruction
- Fibrous “scar tissue” adheres to intestinal loops
* Common complication of abdominal surgeries
Herniation- Mechanical Obstruction
- Intestine protrudes through abdominal wall
* Intestine may strangulates through the opening…inguinal ring, umbilical hernia, hiatal hernia
Intussusception- Mechanical Obstruction
- Telescoping of one part of an intestine on another portion
* More common in ileocecal area
Volvulus (Torsion)- Mechanical Obstruction
- Intestine twist upon itself
* The mesentary “twists” around strangulating the blood supply to the intestine
Tumor Growth- Mechanical Obstruction
• Colon/rectal cancer is most common cause of large intestine obstruction
Paralytic Ileus Causes
- Obstruction that results when peristalsis stops
- Possible causes of ileus:
- Use of certain drugs, such as narcotic pain drugs or high blood pressure medicine
- Abdominal, spine or joint surgery
- Injury or trauma
- Infections/peritonitis
- Heart attack
- Imbalance of electrolytes
- Disorders that affect muscle function
- Low blood supply to parts of intestine (mesenteric ischemia
Treatment Strategies for Paralytic Ileus
- NG tube to “decompress” pressure within GI tract
- Address the underlying cause
- If unsuccessful – surgery may be considered
Hirschsprung’s disease - congenital aganglionic megacolon
A. birth defect – ganglion (nerve) cells of the colon (large intestine ) fail to develop
1. 1 of every 5,000 newborns (M>F)
B. Functional result:
1. impaired motility of colon due to poor coordination/ability to contract intestinal musculature.
2. impacted/trapped stool, infection, inflammation, and constipation.
Categories/Types of Hirschprung’s Disease
Short-segment”
a. rectosigmoid colon
- “Long-segment”
a. regions proximal to rectosigmoid are also involved
Treatment strategies for Hirschsprung’s disease
- decompress the colon (serial rectal irrigation) and surgical removal of involved intestinal segment
a. Mild to moderate cases (e.g. short-segment disease)
b. Severe cases (e.g. enterocolitis)
Inflammatory Bowel Disease- IBD
A. Chronic autoimmune inflammatory disease that damages/ulcerates gastrointestinal tract
2 Types of IBD
- Crohn disease
2. Ulcerative colitis
Crohn’s Disease
- Crohn’s disease can affect any part of the GI tract, though it commonly occurs at the terminal end of the ileum of the SI and in the cecum of the LI.
- Stress may exacerbate symptoms but is not considered a cause of the disease
- Symptoms can range from mild to severe
Epidemiology of Crohn’s
a. Estimated that 500,000 people in US have Crohn’s Disease (1-10 cases per 100,000)
b. Peak onset: 15-25 years (onset up to age 40)
c. Women more often affected than men
d. Familial history
e. 2-4x’s increased risk with first degree relative with disease
Etiology of Crohn’s
a. Cause is poorly understood…the classic “general” theories…genetics, autoimmune and environmental factors.
Pathophysiology of Crohn’s
a. Inflammation extends through all layers of intestinal wall
b. Chronic granulomatous inflammation
• Granuloma – cluster of cells that form in area of inflammation
c. May effects entire GI tract, mouth to anus
d. Distal ileum and proximal colon most often involved
e. Isolated colonic involvement in 25% of cases
f. “Skip lesions” – two or more inflamed areas with healthy bowel in-between
Pharmaceutical Treatment for Crohn’s
strategies depend on severity of symptoms a. Anti-inflammatory drugs • Salicylate (5-ASA preparations) • Corticosteroids • Infliximab (Remicade) b. Immune suppressors c. Antibiotics
Surgical Treatment for Crohn’s
a. Intestinal resection
b. Colostomy/ileostomy
Ulcerative Colitis Pathophysiology
- Ulcerative colitis is chronic inflammatory disease that affects the large intestine.
- Pathophysiology
a. Etiology unknown
b. Inflammation “extends” to mucosa only (does not penetrate deeper layers)
c. Always involves rectum and extends proximally to contiguous sections of colon
d. May see different regional patterns of LI
• Ulcerative proctitis
• Proctosigmoiditis
• Pancolitis
Diverticulosis
Out-pockets” in intestinal wall
a. 85% of patients are asymptomatic
b. 15% develop colicky symptoms
Pathophysiology of diverticulosis
a. Colonic muscle wall weak where vessels penetrate
b. Usually multiple diverticuli present (smaller size)
c. Distribution
• Most commonly found in sigmoid
