FI Flashcards
6 components necessary to maintain anal continence
- stool consistency
- bowel transit
- rectal capacity/compliance
- rectal sensation/sampling reflex
- pelvic floor muscle integrity
- competent anal sphincters
Internal anal sphincter
how think is it?
how much does it contribute to the resting tone?
70%
external anal sphincter provides 30% of the resting
What innervates the external anal sphincter
inferior rectal branch of the pudendal nerve
what is a normal anorectal angle at rest?
95 degrees
what is a normal anorectal angle during a voluntary contraction?
75 degree
what is a normal anorectal angle with BM?
110 - 130 degrees
loss of puborectalis impression
funneling of anorectum
MRI for FI
describe the scoring of levator ani injuries on MRI?
Each side is scored separately on a scale of 0 to 3
0 = no defect
3= complete loss
0-3 is minor
4-6 is major
What supplies motor innervation to the puborectalis?
sacral plexus S3, S4 and inferior rectal nerve
what mediates the sympathetic innervation of the IAS?
postganglionic fibers of hypogastric n.
what nerves mediates the parasympathetic innervation of the IAS?
preganglionic fibers of the sacral n.
describe the hemorrhoid grading system.
Internal - above the dentate line
grade I- no bleeding without prolapse
grade II- prolapse with spontaneous reduction
grade III- prolapse with manual reduction
grade IV- incarecated, irreducible prolapse
external - below dentate line
describe the components of the digital rectal exam
-resting tone
-voluntarily squeeze lasting 5 sec.
Valsalva to assess relaxation of puborectalis
-involuntary contraction with cough
-pain, fissures, hemorrhoids,
-consistency of the stool
-assess for enterocele with valsalva
-masses or lesions
How does Loperamide
work?
opiod recepter agonist–> decreases activity of myenteric plexus in small intestines–>this causes smooth muscle relaxation which increases water absorption
-it also inhibits gastrocolic reflex
Treats diarrhea
does loperamide cross the BBB?
SE of loperamide
no
dry mouth, constipation
Could SNM work for someone with anal sphincter tear?
yes, studies included patients with tears up to 120 degrees.
OASI repair
suture type?
abx?
bowel regimen?
PDS or other absorbable
cefazolin
laxitives.
Name the Rome III criteria to dx constipation
2 or more of the following:
-straining at least 25% of BM
-hard stool at least 25% of BM
-sensation of anorectal blockage at least 25% of the time
-manual maneuvers for BM at 25% of the time
-fewer than 3 BM per week
-insufficient criteria for IBS
how is a transit study performed?
-24 markers in on tablet
-x-ray on day 5
-At least 80% should have been expelled
-if more than 6 markers are left, then its either slow transit or obstruction
How many grams of fiber is recommended per day?
20-35g
How does fiber work to increase stool volume?
stool is mostly bacteria, fiber provides a substrate to increase bacteria growth, thereby increases the volume of stool
undigested fiber absorbs fluid
Name three categoroies of laxitives
- bulk laxatives like fiber
- osmotic laxatives like mag citrate or polyethylene glycol,
3, stimulant laxatives like senna and biscodyl - pharmacotherapy- refer to GI
how do you dx dyssynergia?
MR defecography
digital rectal exam
what is the bubble test for fistula?
put water in the vagina and push air into the rectum. you will see bubbles in the vagina
classification of Fistula
-high
-midlevel
-low
-small vs large
high- apical
midlevel-above the sphincter
low-involves sphincter or distal
small is <2.5 cm
large >/= 2.5cm
You dx a RVF in office.
What is your next step in evaluation?
Imaging?
Needs BX to rule out cancer.
-either referral for scope with bx or perform your own. or send the tract for pathology when excised in the OR.
-CT A/P with and without contrast
-MR enterography
Describe the steps to RVF repair.
- Inspection- sphincter involved or not
- incision-inverted U on the posterior vagina or proctoepisiotmy
- Mobilization and visualization of the relevant muscles: rectal mucosa, internal anal sphincter, levator ani muscles, external anal spinchter, transverse perenei, bulbocavernous
- Tension free Reapproximation of the rectal mucosa, levator ani muscles, end to end sphincteroplasty.
-bulbocavernosous transposition flap or gracilis flap - Skin closure. U or Z flap
What kind of post op restrictions would you give for post RVF repair?
pelvic rest
no lunges
no prolonged sitting
Diet- low residue diet with stool softener
What is a low residue diet?
low fiber
avoid raw fruits and veggies, avoid whole grains, legumes, popcorn
Give some examples of insoluble fiber.
Why does the type of fiber matter?
green leafy vegetables, whole grains, whole wheat
insoluble fiber attracts water into the intestines to increase stool frequency and help with constipation
Give some examples of
soluble fiber.
Why does the type of fiber matter?
fruits, oats, beans,
Dissolves in water to form a gel and slow motility, Helps with diarrhea
Metamucil-psyllium fiber
How many grams of fiber is considered a high fiber diet?
25-35 grams
How much water should one be drinking per day?
32-50 oz per day
Components of a digital rectal exam
- sphincter resting tone and squeeze, symmetry
- length- 3-4 cm
- strength of puborectalis
- angle of anorectal angle
- elevation of the perineum during voluntary squeeze which shows integrity of the rectal vaginal septum
- Valsalva to assess relaxation of the puborectalis
What information can you gather from an anal manometry?
- anal canal length
- anal sphincter pressure with rest and squeeze
- rectal sensation and compliance
- presence or absense of RAIR
- Balloon expulsion test (<60s)
What are the components of the RAIR reflex?
rectoanal inhibitory reflex
relaxation of the IAS when the rectum is distended so you can sample the stool
- Rectum distends
- Anal sampling - IAS relaxes >25% drop in resting pressure
- IAS re-engages to 2/3 of resting pressure
- EAS engages to keep the stool in
risk factors for FI
advanced age
diarrhea
urinary incontinence
vaginal deliveries
sphincter injury
obesity
pelvic rad
diabetes (metformin)
IBS/IBD
Patient presents with fecal seepage.
What dietary change do you recommend and why does this work?
stool bulking bc bulkier stool can trigger the RAIR reflex which engages the external anal sphincter and allows for stool sampling.
4 sub types of rectal dyssynergia
Type 1: good valsalva with paradoxical anal sphincter squeeze
Type 2: no valsalva with paradoxical anal sphincter squeeze
Type 3: good valsalva with absent or little anal sphincter relaxation
Type 4: poor valsalva with absent or little anal sphincter relaxation
you get anal manometry on a patient and the RAIR is absent.
What is your next step?
recommend biopsy to rule out Hirschsprung
list the diagnostic criteria for defecatory dyssynergia
- dx of constipation or IBS-C
- Manometry or EMG evidence of dyssynergia pattern
- abnormal balloon, defecography, transit study
Describe the sequence of events for normal defecation.
- sensory preception of stool
- rectal distention
- contract diaphragm, abd, rectum
- relax EAS
- relax puborectalis muscles
treatment for rectal dyssynergia
-PFPT with biofeedback
-stress management
-fiber, water, exercise
name insoluble fiber supplement
citrucel
linaclotide
MOA
SE
MOA- GC-C agonist- binds to receptor in the intestines, increased fluid in GI tract, leading faster colonic transit
SE- FI, fecal urgency
Compare sphincteroplasty to SNM for FI
sphincteroplasty
initial improvement 85%
5-10 years, 50% with fair improvement
SNM
86% after at least 50% improvement
40% have no FI at 3 years.
risk of FI if they have a second OASI
what if they have a third OASI?
13%
24%
