SI and Colon Dobson Ch 17-4 Flashcards
What four anomalies account for 80% of all obstructions in the bowel?
- hernia (most common cause worldwide)
- intestinal adhesions
- intussusception
- volvulus
Clinical manifestations of SBO?
- Abdominal pain
- Distension
- Vomiting
- Constipation
Where do acquired hernias occur?
anteriorly through the inguinal and femoral canal
How do adhesions cause obstructions?
- create bridges for bowel and other viscera to slide through/under becoming entrapped resutling in internal herniation
- # 1 cause of obstruction in the US
What is a volvulus?
- twisting loop of bowel around its own mesentary
- ressults in obstruction and infarction
What is intussusception?
- Segment of intestine constricted by peristalsis telescopes on its self and becomes trapped
- Most common cause of obstruction in kids younger than 2
What can cause acute arterial obstruction? What results?
- severe atherosclerosis
- aortic aneurysm
- Hypercoaguable states
- oral contraceptives
- embolization of cardiac vegetations or aortic atheromas
Leads to transmural infarction
What age is ischemic disease of the colon most common?
- >70yo
- F>M
- Assoc. with cardiac or vascualar disease ischemia precipitated by therapeutic vasoconstrictiors, small vessel occlusion after CMV or E.coli O157:H7
Onset of acute colonic ischemia?
- Sudden onset of cramping in left lower abdomen
- Desire to defecate
- Passage of blood or bloody diarrhea
When would surgical interventio be necessary with acute colonic ischemia?
- when peristaltic sounds diminish or dissapear
- paralytic ileus
- guarding rebound
- tenderness
Why is the mortality rate doubled in patients with right sided colonic disese?
Right side is supplied by superior mesenteric artery which also supplies small intestines
What can chronic ischemia masquearade as?
IBD with episodes of blood ydiarrhea interspersed with healing
What is angiodysplasia?
malformed submucosal and mucosal blood vessels in the cecum or right colon presenting in 60s
