GI Flashcards
Constipation definition
Less than 3 BM per week
Hard stools
Excessive straining
Incomplete evacuation
Basis for diagnosis of constipation
BM frequency and completeness
Pediatric constipation definition
2 or more of the following w/in 8 weeks:
Fewer than 3 BMs in 1 week
Greater than 1 episode of fecal incontinence a week
Large stool in rectum or palpable on ab exam
Painful defecation
Passing stool large enough to obstruct the toilet
Retentive posturing and withholding behavior
“Functional” constipation definition
2 or more of the following w/in 2 months if older than 4 years or 2 or more of the following within 1 month if younger than 4 years:
2 or less defectations per week
At least 1 episode of fecal incontinence a week
H/o large diameter stools obstructing the toilet
H/o painful or hard BMs
H/o retentive posturing or excessive volitional stool retention
Presence of large fecal mass in rectum
What does withholding cause
Decreased ability to pass stool
Decreased sensitivity to pass stool
Increased stool time in rectum (stool becomes harder/larger)
Constipation differential diagnosis
Anatomic
Dietary
Medication related
Constipation differential diagnosis: anatomic
CF
Metabolic and endocrine (DM, hypercalcemia, hypothyroidism)
Neurologic (Cerebral palsy, Hirschsprung disease, Spina Bifida)
SLE
Constipation differential diagnosis: Dietary
Dehydration
High in fat
Low in fiber
Constipation differential diagnosis: medication related
Antacids - Ca containing Antidepressants Antihistamines Cathartics (abuse/overuse) Iron supplements Opioids Pseudoephedrine Vincristine
Constipation s/sx
Ab distention
Ab pain
Bloating
Nausea
Functional constipation s/sx
Becoming fidgety Decreased appetite Decreased food intake Rocking back and forth Standing on tiptoes
Constipation non-pharmacologic treatment
Behavior modification
Diet
Digital disimpaction
Constipation pharmacologic treatment
Lubricants (soften stool, prevent reabsorption of water)
Osmotic laxatives
Osmotic enemas
Stimulant laxatives
Constipation pharmacologic plan to avoid recurrences
Lubricants
Osmotic laxatives
Stool softener
Stool softener
Docusate
Reduces surface tension on the water/oil interface in stool
Increases water absorption in stool
Diarrhea definition
> /= 3 water, loose stools per day
Acute diarrhea
Increased number and stool consistency change for less than 7 days
Chronic diarrhea
Diarrhea lasting more than 14 consecutive days
Diarrhea pathophysiology
Normal GI tract fx is impaired (Impaired fluid and electrolyte balance)
Fluid volume in GI lumen
How is fluid volume in the GI lumen affected in diarrhea?
Dietary fluid intake
Intestinal secretions
Colonic reabsorption
Electrolyte contents in fecal stool
Na - 40
K - 90
Cl - 15
Na bicarb - 30
Types of diarrhea
Secretory
Osmotic
Exudative
Changed motility
Secretory diarrhea
Stimulant
Increases secretion of water into lumen
Decreases absorption of water and electrolytes from lumen (inhibits Na/K ATP ase)
Secretory diarrhea causes
Bacterial toxins Hormones (secretin) Increased bile acids Laxatives Unabsorbed dietary fat
Osmotic diarrhea
Created of osmotic gradient in lumen d/t poorly absorbed substances in GI tract
Osmotic diarrhea causes
Lactose intolerance
Malabsorption
Medications (lactulose, Mg containing products)
Exudative diarrhea
Injury to mucosal lining in lumen
Inflamed intestine prevents proper water and electrolyte transfer
Exudative diarrhea causes
IBD (CD/UC)
Changed motility diarrhea
Decreased time for normal absorption
Changed motility diarrhea causes
Bacterial over growth
Early colonic emptying
Reduction in small intestine transit time
Viral diarrhea differential diagnosis
Adenovirus
CMV
Norovirus
Rotavirus
Bacterial diarrhea differential diagnosis
C diff E coli Salmonella Shigella Yersinia
Parasitic diarrhea differential diagnosis
Cryptosporidium
Entameba histolytica
Giardia
Toxin diarrhea causes
C diff toxin
Enterotoxins
Exposure diarrhea causes
Chemo Laxative abuse/overuse Medications Radiation Tumor secretions
Malabsorption diarrhea causes
Allergic enteropathy Celiac disease Chronic liver disease Glucose/galactose transport defect Pancreatic insufficiancy
IBD diarrhea causes
Allergic colitis
CD
Eosinophilic gastroenteritis
UC
Intake diarrhea causes
High carb load
Non-pharmacologic treatment of diarrhea
Restore fluid and electrolyte balance Adjust diet (continue feedings during acute diarrhea phases)
Oral replacement therapy
Pedialyte
Enfalyte
Rehydralyte
Cerelyte
Pharmacologic treatment of diarrhea
Bismuth subsalicylate Cholestyramine Probiotics Psyllium Opioids Vitamin A Zinc
Bismuth subsalicylate
Facilitated extra water absorption from the lumen
Inhibits PGs decreasing GI tract inflammation
Caution with viral infections
Cholestyramine
Used in increased bile acid related diarrhea
Duration of therapy in patients under 2 years of age = 2 days
Interactions with medication absorption
Opioid examples
Diphenoxylate
Loperamide (do not use under 3 yo)
Morphine
GERD definition
Passage of stomach contents into the esophagus
GERD mechanism
LES relaxation (w/out swallowing) Stomach contents reflux into stomach
GERD in pediatric non-pharmacologic treatment
Feeding changes
Change volumes
Modify frequency
Thicken feeds
GERD sx
Ab pain
Food refusal
Heartburn
Regurgitation
GERD complications
Barrett’s esophagus
Hemorrhage
Reflux esophagus
Stricture
GERD RF
Chronic lung disease
Esophageal atresia
Neurologic impaired (cerebral palsy)
Prematurity
H2RA disadvantages
ADR: HA, irritability, somnolence
Tolerance development
GERD pharmacologic treatments
Antacids H2RAs Prokinetic agents PPI Surface-protectant agents
Prokinetic agent advantages
Facilitates gastric emptying
Improves sx
Prokinetic agent disadvantages
ADR: EPS, GI upset, hepatotoxicity
Limited evidence
Not efficacious
Prokinetic agent examples
Bethanecol
Erythromycin
Metoclopramide
PPI ADRs
Constipation
Diarrhea
HA
Nausea
Surface-protectant agent advantages
Aids mucosal healing
Low risk of ADR
