GI Mod 3B Flashcards
two forms of pyloric obstruction
- infantile hypertrophic pyloric stenosis
2. adult/acquired pyloric obstruction
what is IHPS
infantile hypertrophic pyloric stenosis: aka congenital pyloric stenosis
s/s of IHPS
infant at 2-3 weeks begins to vomit for no apparent reason
projectile vomiting - several feet
frequency of IHPS
infant disorder - 3/1000 births
pathophys of IHPS
pyloric sphincter is hypertrophied
etiology of IHPS
not fully established
hormones to allergic rxns have been suggested as potential cause
treatment of IHPS
surgery - pyloromyotomy
adult/acquired pyloric obstruction
- cause
- s/s
- tx
caused by severe peptic ulcer or tumor in area
vague s/s of epigastric discomfort/fullness with eating that progresses to severe epigastric discomfort
gastric distention, nausea, progress to vomit and acute distress as obstruction develops over time
-tx: address cause of obstruction
types of mechanical obstructions
- adhesions
- herniation
- intussusception
- vulvulus (torsion)
- tumor growth
what are adhesions
fibrous scar tissue adheres to intestinal loops
common complication of abdominal surgeries
what are herniations
intestine protrudes thru abdominal wall
intestine may strangulate thru the opening…inguinal ring, umbilical hernia, hiatal hernia
what is intussusception
telescoping of one part of an intestine on another portion
more common in ileocecal area
what is volvulus (torsion)
intestine twists upon itself
the mesentary twists around strangulating the blood supply to the intestine
MC cause of LI obstruction d/t tumors
colon/rectal cancer is MC cause of LI obstruction
what causes functional obstruction in GI
paralytic ileus
what is paralytic ileus
obstruction that results when peristalsis stops
possible causes of ileus
certain drugs (narcotics or HTN drugs) abdominal, spine or joint surgery injury/trauma infections/peritonitis heart attack imbalance of electrolytes disorders that affect muscle function low blood supply to parts of intestine (mesenteric ischemia)
treatment strategies of paralytic ileus
NG tube to decompress pressure within GI tract
address the underlying cause
if unsuccessful - surgery may be considered
Hirschsprung’s dz
aka congenital aganglionic megacolon
- birth defect: ganglion nerve cells of the colon fail to develop
- functional result: impaired motility of colon due to poor coordination/ability to contract intestinal musculature; impacted/trapped stool, infection, inflammation, and constipation
categories/types of Hirschprung’s dz
short - segment - rectosigmoid colon
long - segment - regions proximal to rectosigmoid are also involved
treatment strategies of Hirschsprung’s dz
decompress the colon (serial rectal irrigation) and surgical removal of involved intestinal segment
- mild-mod cases (short seg dz)
- severe cases (enterocolitis)
IBD - what is it
chronic autoimmune inflammatory dz that damages/ulcerates GI tract
two forms of IBD
- Chrohns dz
2. ulcerative colitis
what is Crohn’s dz
Crohn’s dz 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 s/s but is considered a cause of the dz
- s/s may be mild to severe
how many peeps in US have Crohn’s
500,000 in US
peak onset of Crohn’s
15-25 years up to 40
women or men are affected more with Crohn’s
women
is Crohn’s genetic
yes
what increases risk of Crohn’s 2-4x
first degree relative with dz
etiology of Crohn’s
cause is poorly understood - classic theories - gentics, autoimmune, environment
pathophys of Crohn’s
- what regions can it affect
- types of lesions
inflammation extends thru all layers of intestinal wall
chronic granulomatous inflammation
may effect entire GI (mouth to anus)
distal ileum and proximal colon most often involved
isolated colonic involvement in 25% of cases
skip lesions - two are more inflamed areas with healthy bowl in bw
what are granulomas in Crohn’s
cluster of cells that form in area of inflammation
Pyloric obstruction
narrowing of pylorus
pharmaceutical tx of Crohn’s Dz
antiinflammatory drugs - salicylate, corticosteroids, infliximab
immune suppressors
antibiotics
surgical tx of Crohns
intestinal resection
colostomy/ileostomy
what is ulcerative colitis
chronic inflammatory dz that affects the large intestine
pathophys of ulcerative colitis
etiology unknown
inflammation extends to mucosa only (does not penetrate deeper layers)
always involves rectum and extends proximally to contiguous secretions of colon
what are the different regional patterns in ulcerative colitis in LI
ulcerative proctitis
proctosigmoiditis
pancolitis
pharmaceutical interventions of ulcerative colitis
similar to crohn’s
surgical tx of ulcerative colitis
- total proctocolectomy (brooke ileostomy)
entire colorectal mucosa excised - ileal pouch anal anastomosis
pt maintains anal function an continence
what is diverticulosis
out pockets in intestinal wall
85% of pts are asymptomatic
15% develop colicky symptoms
pathophys of diverticulosis
colonic muscle wall weak where vessels penetrate
usually multiple diverticular present (smaller size)
distribution of diverticulosis
most commonly found in sigmoid colon
tx/management of diverticulosis
high fiber diet
avoid high residue foods (seeds, nuts, corn)
-anecdotal strategy based on theory to prevent from small undigested pieces from getting lodge in diverticula - evidence not fully established
what is diverticulitis
inflammation of the diverticuli
impacted with fecal material
what is most often affect in diverticulitis
sigmoid colon
colon perforations due to what in diverticulitis
inflammation
two types of perforations in diverticulitis
- simple diverticulitis
- complicated diverticulitis
(perforations may or may not penetrate intestinal wall)
what % of newly diagnosed cancer in US is colorectal cancer
8.5%
pathophys of colorectal cancer
- most CRC develop from adenomatous polyp
- initial mutant cancer cell develops in polyp
- slow growth on polyp as it progresses down the stalk toward the deeper layers of the mucosa
- if cancer penetrates into sub mucosal it can reach lymphatic/BV pathways and become highly malignant
how to prevent colorectal cancer
screening and removal of polyps
risk factors for CRC
age >50
PMH: IBD, adenomatous polyps >5mm, gall bladders urgery, pelvic irradiation
FHx: 1st degree relative with colorectal cancer, familial adenomatous polyposis, hereditary nonpolyposis colorectal cancer
Lifestyle: tobacco and BMI >35-40
screening for CRC
colonoscopy - considered more thorough screening tool
sigmoidoscopy - limited in ability to screen
protocols for screening for CRC
average risk pts >50yo
- colonoscopy every 10years
- digital rectal exam and fecal occult blood yearly
- pts with increased risk require more frequent or aggressive monitoring
