D/O of small and large bowel and anorectum Flashcards
What are the 3 different types of mechanical SBO?
Simple: partially occluded at 1+ points without compromising intestinal blood supply
Closed loop: obstructed at 2 sequential sites (eg twisting) at high risk of obstruction of blood flow
Strangulation: compromise of intestinal blood flow
List 10 causes of SBO
External to intestinal wall
- adhesions
- hernias
- volvulus
- compressing masses
Intrinsic to intestinal wall
- primary neoplasm
- inflammatory
- infectious (eg TB)
- intussusception
- traumatic (eg intestinal wall hematoma)
Intraluminal
- bezoars
- FB
- Gallstones
- ascaris infestation
What degree of SB dilation is suggestive of SBO
GT 3cm
What is the string of pearls sign?
Suggests SBO
small amt of air trapped in fluid filled bowel
Describe the 4 distinct causes of acute mesenteric ischemia:
- arterial embolism: usually cardiac source
2arterial thrombosis: usually SMA from atherosclerosis
3venous thrombosis: trauma, hypercoagulable state
4low flow state: sepsis, cocaine, vasopressors
List 10 factors assoc with mesenteric venous thrombosis
Hypercoagulable state
- Polycythemia
- sickle cell
- antithrombin def
- protein C/S def
- malignancy
- myeloproliferative d/o
- estrogen therapy
- pregnancy
Inflammatory
- pancreatitis
- diverticulitis
- appendicitis
- cholangitis
Traum -operative venous injury postsplenectomy blunt abdo trauma CHF Renal failure decompression sickless portal HTN
What is the antibiotic treatment of uncomplicated diverticulitis (Box 95-4)?
7-10 days of
Septra DS 1 tablet BID AND flagyl 500mg q6
OR
cipro 750mg bid + flagyl 500mg q6
OR
amox-clav ER (1000/62.5mg) 2 tablets bid
F/U in 2-3d
What is complicated diverticulitis
- More extensive disease including abscess formation, peritonitis, intestinal obstruction, fistula formation
- Sx
o LLQ to diffuse tenderness
o Dysuria/fecal matter from urethra/vagina
o Palpable mass
o Obstructive symptoms - Dx: CT preferred method of imaging
o Shows colon and surrounding structures
o Can be used to guide percutaneous drainage of abscesses
o Shows alternate dx
o May have small diverticula even when scan negative, thickened bowel wall may be mistaken for cancer, may need endoscopy to evaluate
o SN 69-95%, SP 75-100%
Tx – Sx consult for admission, perforation/peritonitis/drainage of large abscesses
What is the treatment of complicated diverticulitis (Box 95-5)?
Mild to moderate
Cipro 400mg IV q12 + flagyl 1g IV q 12
Severe:
PIp-Tazo or ceftriazone + flagyl
List 8 causes of LBO:
- Most frequently associated with malignancy (50% of operative cases)
- Volvulus
- Diverticular disease
- Fecal impaction
- Strictures (from IBD)
- Adhesions
- Hernia
- Pseudo-obstruction (Ogilvie’s Syndrome)
At what cecal diameter should you be concerned for risk of perforation?
12+ cm
What are the locations of colonic volvulus
and how are they treated
cecal: surgical detorsion
sigmoid: endoscopic detorsion
List 5 complications of IBD:
- Fistulas
- Strictures
- Abcesses
- Toxic megacolon
- Fulminant colitis
- Perforation
What factors are associated with colonic ischemia?
Primary insult is low flow state:
- CHF
- Vasoconstrictive drugs
- Atherosclerosis
- Renal failure
- Recent significant surgery (cardiac, vascular)
- Recent significant medical illness
Younger patients:
- Collagen vascular disease
- Hematologic disorders (thrombophilia)
- Long distance running
- Cocaine use
Medication related:
- Digoxin
- Pseudoephedrine
- Sumatriptan
How is continence maintained?
sympathetic fibers from L1-3 and L5 for internal sphincter contraction
external sphincter is voluntary
elimination controlled by parasympathetic fibers S2-4
