Download The Straight Poop… - Emory University Department of Pediatrics

The Straight Poop…
or how I learned to stop worrying and love the bomb
Michael F. Ziegler, MD
Assistant Professor
Departments of Pediatrics and Emergency Medicine
Emory University
Constipation
►
Occurrence
 3% of visits to Pediatricians
 25% of visits to
Gastroenterologists
►
Definitions
 Difficult or infrequent bowel
movements
 Painful defecation
 Passage of hard stools
 Sensation of incomplete
evacuation of stool
North American Society for Pediatric
Gastroenterology Hepatology and Nutrition
(NASPGHAN)
► Constipation
 “Delay or difficulty in defecation, present for
two or more weeks and sufficient to cause
significant distress to the patient”
► Baker,
et al J Pediatr Gastroenterol Nutr 1999; 29
Paris Conference
► Constipation
 Two or more of the following occurring over the
preceeding 8 weeks:
►Frequency
of BMs <3/week
►>1 episode of fecal incontinence/week
►Large stools in the rectum or palpable on the
abdominal exam
►Passage of stools so large they obstruct the toilet
►Retentive posturing and withholding behavior
►Painful defecation
► Benninga,
et al J Pediatr Gastroenterol Nutr 2009;40
Colon Physiology
► Muscular
contractions propel and mix contents
 Increased on waking and after meals (The Gastrocolic
Reflex)
► Reabsorption
of water and electrolytes mostly in
cecum and transverse colon
 Primarily water follows osmotic gradient as Na is
absorbed through the lumenal wall
 Adult colons can handle 1.5 liters of fluid per day with
only 100-150cc water excreted
 Under certain circumstances can handle 4.5 liters/day
without causing diarrhea
Colon Physiology
► Rectal
function
 Material passes into rectum via propulsive
contractions until rectum begins to dilate
causing reflex relaxation of the internal anal
sphincter and contraction of the rectal detrussor
muscles
Rectal Function
► “I
want to go”
 The puborectalis muscle
(forms the anorectal
angle) and levator ani
muscles relax
straightening the
anorectal angle
 Straining increases
intraabdominal pressure
 Feces is expelled
Rectal Function
► “Not
now, my date
wants to cuddle”
 Contract external anal
sphincter
 Prevents defecation and
allows rectal wall to
adapt to increased
volume or reset for the
next stimulation
Pathophysiology of Constipation
►
Defective/Impaired Propulsion (<5%)
 Diet deficient in bulk (fiber)
 Milk Protein Allergy
 Neuropathy/myopathy
► Cerebral palsy
► Spinal cord lesions
 Metabolic
►
or  Ca; K; Mag; Phos
► Hypothyroidism, Hyperparathyroidism
► Cystic fibrosis
► Celiac disease
 Medications
► Narcotics
► Anticholinergics
Pathophysiology of Constipation
► Defective/Impaired
Sensation
 Primary sensory impairment such as spinal cord
abnormalities (<5%)
 Secondary sensory abnormalities such as megarectum
from chronic fecal retention*
► Outlet
Obstruction
 Mechanical (<5%)
► Anal
stenosis
► Hirshsprung’s Disease
 Functional*
► *>95%
of all constipation
Differentiating Organic Disease
(<5%)
► Failure to thrive
► Abdominal distension +/- vomiting
► Anterior anus
► Tight anus
► Patulous anus
► Nevi or sinus in lumbosacral region
► Multiple Café-au-lait spots
► Abnormal tone or strength
► Abnormal lower extremity reflexes
► Blood in the stool
Functional vs Organic
Functional
Organic
Since birth
Never
Common
Retentive posturing
Common
Unusual
Encopresis
Common
Rare
Large caliber stools
Common
Unusual
Hx of obstruction
Rare
Common
Failure to Thrive
Unusual
Common
Distended abdomen
Common
Occasional
Stool in ampulla
Common
Rare
Rectal ampulla
Dilated
Narrow
Common presentations
ROME II Diagnostic Criteria
► Infant
Dyschezia
 <6mo
 Strains for ≥10 min
 Passage of soft stools
►Basic
regulatory mechanisms to control defecation
present in newborn
►Failure to coordinate increased intraabdominal
pressure with relaxation of pelvic floor
►Dissipates with development
Common presentations
ROME II Diagnostic Criteria
► Functional




constipation
Infants and preschool children
Associated with formula changes
No organic cause
Passing hard stools ≤ 2/week
►Use
of fruit juices and medications with high sugar
content softens stools and eases evacuation
Common presentations
ROME II Diagnostic Criteria
► Functional
Fecal Retention
 Potty training and on
 Retentive behavior
 Defecation avoidance
►“The Poop Dance”
 Anxious
 Stiff body
 Cross legs; walks on tip toes
 Hop up and down
 Runs to corner or hides behind couch
►Leads
to fecal retention and overflow soiling
Functional Constipation with
Encopresis
► Dilation
of rectum leads to loss of normal
sensation to defecate, however, internal
sphincter still relaxed
► Stool remains in contact with dehydrating
physiology longer
► Proximal liquid stool runs around hard stool
and passes out of anus often without
awareness
Triggers to functional constipation
►
►
Most common is painful or frightening defecation; single
event can precipitate (i.e. like PTSD)
Age differences
 Toddlers
► Dietary
changes (Cow’s milk) lead to dry hard stools w/ fissures and
pain
► Toilet training can lead to excessive parental pressure, anxiety,
exertion of own will
 Older children
► Unpleasant toilet
► Sexual abuse
►
facilities away from home
All stool holding behaviors lead to further dehydration of
stool and a vicious cycle of painful defecation and stooling
avoidance
Constipation in the ED
► Infant
 straining patterns
► Toddlers
 hard stools, blood on stool (fissures)
► Older
children
 abdominal pain
 often unaware they are constipated
Emergency Department Eval
►
History






►
PE
Onset of sxs
Growth pattern
Presence of blood
Consistency and caliber of stools
Vomiting
Recurrent abdominal pain
 Palpable mass in lower abd
 Observe anus location and local pathology
 Neurologic eval with anal wink, cremasteric
reflex and DTRs in Les
 Digital Rectal Exam (Sensitivity
88.6%/Specificity 41.6%)
Emergency Department Eval
► Radiographs
 Several studies advocate use of plain abdominal films
to assess presence of stool, however, stool in the
colon is physiologically normal so what does it mean?
Does presence of stool = impaction?
 ED Physicians do rectal exams <75% of the time and
order radiographs 70% of the time.
 Frequently films used to “explain” sxs as attributed to
constipation (i.e. appy explained away as
constipation)
 “conflicting evidence for an association between
clinical symptoms of constipation and fecal loading of
radiographs in children. Use of films cannot be
supported.” Reuchlin-Vroklage, et al Arch Pediatr Adolesc Med 2005;
159
Treatment
► Infants-
Infant Dyschezia
 Mostly reassurance
 Osmotic agents to soften stools
► Prune
juice/Malt soup extract/Corn syrup
 Glycerin suppositories for immediate evacuation (Avoid
Use of Enemas in children under 2yo)
► Toddlers-Functional
Constipation
 Avoid focus on toilet training
 Osmotic agents to soften stools and allow healing of
fissures
Treatment
► Older
children- Functional Fecal Retention
 Two step procedure
►Immediate
disimpaction (3-5 days)
 Oral or rectal routes
►Maintenance
(6-12 months)
 Oral routes
► Typically mineral oil or polyethylene glycol
Dosage
Risks
Osmotic agentsMag/Lactulose/Sorbitol
Varies
Cramps/flatulence/Mag
intoxication
LubricantsMineral oil
Disimpaction 15-30 cc/yr
of life daily
Maintenance 1-3cc/kg/d
Lipoid pneumonitis/
Fat soluble Vit not
malabsorbed
StimulantsSenna/Bisacoyl
Varies
Idiosyncratic
hepatitis/analgesic
nephropathy/K
FiberBran/Psyllium
2.5cc powder in 240cc
water TID
Requires water; if not
enough can constipate
Osmotic enemaPhosphate enemas
6cc/kg
Trauma/bacterial
translocation/electolyte
shifts (Phos/Ca)
(Do not use in infants or neurologically
impaired)
LavagePEG
Disimpaction 25cc/kg/hr Cramps/vomiting/
Maintenance 5-10cc/kg/d pneumonitis
Or 0.78gm/kg/d
Enemas-A good and a bad idea
► Magnesium
enemas (also PO)
 Acute mag toxicityCa/PhosComa and Cardiac
conduction defects, as well as, shock from fluid shifts
► Phosphate
enemas
 Electrolyte disturbances and fluid shifts
► Soap
suds enemas
 Bowel wall necrosis and perforation
► Tap
water enemas
► Milk
& Molasses enemas
 Water intoxication/hypervolemiaelectrolyte
disturbanceseizures and death
 Fermentationperforation
 Fluid and electrolyte shifts do happen
A Medical Position Statement of the
NASPGHAN
► General
Rec
 Thorough Hx/PE-sufficient to dx functional
constipation in most cases
 Stool for occult blood in all infants and children
with risk factors for organic disease
 Abdominal radiographs can be useful
 Rectal Biopsy only reliable way to exclude
Hirshsprung’s Disease
A Medical Position Statement of the
NASPGHAN
► Rec
for Infants
 Disimpaction via glycerin suppositories; avoid
enemas
 Osmotic and stimulant agents can be used
 Avoid mineral oil
 PEG has been shown to be safe in infants in a
small limited trial
A Medical Position Statement of the
NASPGHAN
► Rec
for children
 Disimpaction via oral or rectal routes okay
 Balanced diet with fiber containing foods
 Medications in conjunction with behavioral
modification decreases time to remission
 PEG is effective for acute disimpaction and
maintenance therapy and is the best tolerated
of all regimens
Hiddie Ho