Vomiting, Diarrhea, Constipation Flashcards
Nausea and vomiting pathway
Brainstem mediated in medulla, stimulated by:
- Afferent vagal fibers from GI viscera 5-HT3 receptors due to biliary or GI distention, mucosal or peritoneal irritation, or infections.
- Vestibular system, H1 and muscarinic cholinergic receptors
- Amygdala (sights/smells/emotion)
- Chemoreceptor trigger zone (outside blood brain barrier; rich in opioid, serotonin 5-HT3, dopamine D2 receptors)
Visceral afferent stimulation caused by Mechanical obstruction
malignancy, gastric volvulus, peptic ulcer disease, adhesions, hernias, Crohns,
carcinomatosis
With abdominal/epigastric pain, always think
cardiac (MI)
Pancreatitis causes epigastric pain that radiates to
back (will see increased lipase on blood tests)
Cholelithiasis
gallstones
Cholecystitis
inflamed gallbladder
Choledocholithiais
stone on common bile duct
Visceral afferent stimulation caused by dysmotility
gastroparesis (from diabetes, post viral, post vagotomy), scleroderma, amyloidosis, familial myoneuropathies
Visceral afferent stimulation caused by peritoneal irritation
peritonitis, perforated viscus, appendicitis, spontaneous bacterial peritonitis, viral gastroenteritis, Norwalk agent, rotavirus, food poisoning toxins from Bacillus cereus, Staph aureus or clostridium perfringens, Hep A or B, acute systemic infection
Visceral afferent stimulation caused by Hepatobiliary or pancreatic disorders
acute pancreatitis, cholecystitis/lithiasis
Visceral afferent stimulation caused by topical GI irritants
alcohol, NSAIDs, antibiotics (Tetracyclines- take with milk or crackers)
Visceral afferent stimulation caused by Post op/other
cardiac disease, acute MI, heart failure, urologic disease, stones, pyelonephritis
Vestibular disorders that can cause N/V
Labyrinthitis, Meniere syndrome, motion sickness
CNS disorders that can cause N/V
Increased intracranial pressure (CNS tumors, subdural/subarachnoid hemorrhage) Migraine infections (meningitis, encephalitis) Psychogenic- anticipatory vomiting, anorexia/bulimia, psych disorders
Irritation of CRTZ
- Antitumor & Chemo/ Radiation meds
- Meds/Drugs (opioids, anticonvulsants, antiparkinsons, Bblockers, antiarrhythmics, digoxin, nicotine, BC pills, cholinesterase inhibitors, diabetes meds)
Systemic disorders that can irritate CRTZ
Diabetic ketoacidosis, uremia, adrenocortical crisis, parathyroid disease, hypothyroidism, pregnancy, paraneoplastic syndrome
History clues- morning vomiting?
Pregnancy, alcohol, increased ICP
History clues- after meals?
Biliary (think gallstone or gallbladder issue possibly)
History clues- undigested food?
Gastroparesis or gastric outlet obstruction
History clues- green emesis?
Bowel obstruction, biliary (classic presentation)
Rebound pain?
Peritonitis
RUQ pain? Murphy’s sign?
appendicitis
Pelvic pain in woman?
gyn/ovarian pathology
CMP will show
CLASSIC: Hypochloremic, hypokalemic, metabolic alkalosis (prolonged emesis)
-Could be from vomiting, diuretics
Other Tests to order
- KUB (kidney, urinary, bladder), Obstructive Series (xrays standing, sitting, laying, to check air fluid levels)
- NM Gastric Emptying Study
- Barium Upper GI Study (up to small intestine)
- EGD (put camera in mouth/down throat to look into stomach)
- CT w or w/o, RARELY w and w/on (note that is 2 scans) usually only WITH or WITHOUT
- Head CT? to rule out tumor
Small bowel obstruction on Xray
MUST KNOW FOR TEST!!
-air fluid levels (and stool on X-ray)
Complications
Dehydration, electrolytes, aspiration, Boerhaave’s Syndrome, Mallory Weiss Tears
Aspiration- if someone throws up look for complications; if they throw up and take deep breath, vomit goes into lungs, causes chemical inflammation- may show up hours or days later- if they spike a fever- start on ________
antibiotic for anaerobic coverage (bacteria from gut is in lungs)
Mallory Weiss Tears
small tear in esophagus and you throw up blood- from force of throwing up (bulimics and alcoholics)
Boerhaave’s Syndrome
esophageal rupture (in FA)
Treatment
-Symptomatic management (clear liquids to full liquids to soft diet) -Admit patient? -NG tube? Tube from nose to stomach -Antiemetic Medications
Antiemetics- Serotonin 5-HT3 antagonists
Ondansetron (most common), Granlsetron (chemo patients), Dolasetron, Palonosetron
Antiemetics- Dopamine receptor antagonists
Metoclopramide, Prochlorperazine, Promethazine, Trimethobenzamide
Marijuana as antiemetic
-THC active ingredient, available by Rx as dronabinol
-Helps with nausea of chemotherapy, has CNS side effects
-NOTE: some have paradoxical reaction, Cyclic Vomiting Syndrome, Canabis Hyperemesis Syndrome
Classic History: Improvement of symptoms of N/V with taking a hot shower
Diarrhea
200-300g in 24 hour period or more than 3 bowel movements per day or liquidity
Non-inflammatory Acute Diarrhea
Inflammatory Acute Diarrhea
- Blood, pus or fever (BAD- invasive pathogen)
- Invasive organism or toxin producing
- Clostridium difficile, E coli O157:H7 (Isolation, spore forming, hard to kill, not hand sanitizer, only soap and water, test for this in stool)
What food to avoid during pregnancy and why
Avoid soft cheese- higher risk of Listeriosis
Day care and hiking cause higher risk of
Giardia or cryptosporidium
Using antibiotics (like Cipro from travelers diarrhea)
May cause C diff colitis
Antibiotics for C diff
metronidazol (first line)- Vanco if that doesn’t work
For pt with C diff or E coli DO NOT GIVE
Do NOT give immodium (loperimide) or diphenoxylate with atropine, risk of increased contact time with gut (increased risk for systemic infection, body can’t get rid of it)
Stomach virus from cruise ship
Norovirus
Noninflammatory diarrhea is from
- norovirus, rotavirus
- giardia, cryptosporidium, cyclospora
- preformed enterotoxins (s. aureus, bacillus cereus, clostridium perfringens)
- enterotoxin production (enterotoxogenic E coli, vibrio cholerae)
Inflammatory diarrhea is from
- CMV
- entamoeba histolytica
- Cytotoxin production (vibrio parahaemolyticus, EHEC O157:H5, C. diff)
- Mucosal invasion (shigella, campy, salmonella, EIEC, aeromonas, pleisomonas, yersinia, chlamydia, n. gonorrhea, listeria)
Treatment
- Bismuth subsalicylate (Pepto- can turn stool black), good for traveler’s
- Loperamide: opioid receptor agaonist
-Inflammatory Bowel Disease?
UC (ulcerative colitis) vs. Crohn’s (terminal ilea)
Osmotic diarrhea
- stool volume decreases w/ fasting, increased stoop osmotic gap
- from meds (antacids, lactulose, sorbitol)
- from dissacharidase deficiency (lactose intolerance)
- factitious diarrhea (magnesium in antacids/laxatives)
Secretory diarrhea
- large volume (> 1L/day), little change with fasting, normal stool osmotic gap
- hormonally mediated (carcinoid, zollinger ellison syndrome-gastrin)
- factitious diarrhea (laxative abuse)
- villous adenoma
- bile salt malabsorption (idiopathic, crohns ileitis, post- cholecystectomy)
- meds
Inflammatory conditions
- fever, hematochezia, abdominal pain
- UC, crohns, microscopic colitis
- malignancy (lymphoma, adenocarcinoma with obstruction and pseudodiarrhea(
- radiation enteritis
Meds causing diarrhea
-SSRIs, cholinesterase inhibitors, NSAIDs, PPIs, ARBs, metformin, allopruinol
Malabsorption syndromes
- weight loss, abnormal lab values, fecal fat > 10g/24 hrs
- small bowel mucosal disorders (celiac sprue, tropical sprue, whipple dx, eosinophilic GItis, small bowel resection, crohns)
- Lymphatic obstruction (lymphoma, carcinoid, infectious (tuberculosis), Kaposi sarcoma, sarcoidosis, retroperitoneal fibrosis)
- Pancreatic dx (chronic pancreatitis, cancer)
- Bacterial overgrowth (motility disorder like diabetes or vagotomy, scleroderma, fistulas, small int diverticula)
Motility disorders
- systemic disease, prior abdominal surgery
- postsurgical (vagotomy, partial gastrectomy, blind loop with bacterial overgrowth)
- systemic disorders (scelroderma, DM, hyperthyroidism)
- IBS
Chronic infections
- parasites (giardia, e. histolytica, strongyloidiasis, capillaria)
- AIDS related (CMV, HIV, C diff., mycobacterium avium complex, microsporidia, cryptosoiridium, Isospora belli)
A 90 year old male with PMH of HTN, DM presents to your office with complaint of constipation. He reports normally would have a BM every day, but now often goes 2 days without one.
What do you tell the patient?
Prune juice- start with this- natural laxative
Constipation overview
- 10-15% of adults
- More common in women, elderly
- If bed bound, may be due to inability to get to toilet
- History is key
- Physical examination: rectal exam, FOBT (fecal occult blood testing)
- Labs: BMP, Mag, TSH
- Colonoscopy? not usually, unless you think tumor
Most common causes of constipation are from
- inadequate fiber/fluid intake
2. poor bowel habits
System diseases that can cause constipation are
- endocrine (hypothyroidism, hyperparathyroidism, DM)
- metabolic (hypokalemia, hypercalcemia, uremia, porphyria)
- neuro (parkinsons, MS, sacral nerve damage from prior pelvic surgery or tumor, parapalegia, autonomic neuropathy)
Meds that can cause constipation
-opioids, diuretics, calcium channel blockers, anticholinergics, psychotropics, calcium/iron supplements, NSAIDs, clonidine, cholestyramine)
Structural abnormalities causing constipation
- Anorectal (rectal prolapse, rectocele, rectal intussusception, anorectal stricture, anal fissure, rectal ulcer syndrome)
- Perineal descent
- Clonic mass with obstruction/adenocarcinoma
- Hirschsprung disease
- Colonic stricture (radiation, ischemia, diverticulosis)
- Idiopathic megarectum
Slow colonic transit can cause constipation from
- idiopathic
- psychogenic
- eating disorders
- chronic int pseudo-obstruction
Other things causing constipation
Pelvic floor dyssynergia or IBS
Zollinger Ellison syndrome
gastin secreting tumor
Primary Constipation description
- Normal transit time is 35 hours, more than 72 hours is abnormal
- Impaired relaxation of anal sphincter and/or pelvic floor muscles
- Irritable Bowel Syndrome (IBS)- chronic abdominal pain, gets BETTER with bowel movement- sign of IBS, alternate diarrhea and constipation
Secondary Constipation
-Systemic disorders, medications, obstructing colonic lesions
(Hypercalcemia, hypokalemia, hypothyroidism, calcium channel blockers like amlodipine/nifedipine)
-Cancer (Warning signs: Age >50 with hematochezia, weight loss, anemia, FOBT +, family history of colon CA, IBD patients–>refer to gastroenterologist)
Treatment options
-Lifestyle measures
-Dietary changes
-Mineral oil
-Laxatives, Osmotic laxatives, Stimulant laxatives
(Magnesium citrate – AKA “liquid TNT” – Magnesium Mg “makes you go”)
-Prune juice
-Enema or Suppository
-For fecal Impaction use manual disimpaction
-OMT: colonic milking
For Opioid Induced Constipation use
Methylnaltrexone (Relistor):
subcutaneous injection, expensive, blocks opioid receptors in gut only
Examples for stool surfactants
-Docusate sodium, mineral oil
Examples of Osmotic laxatives
-Magnesium oxide, lactulose or sorbitol, polyethylene glycol
Examples of stimulant laxatives
bisacodyl, cascara, senna
First line therapy (note from class)
Senna and docusate may come in combined pill- may cause cramping –> first line therapy
Drug good for constipated pts with liver problems
Lactulose- good for liver patients, prevents ammonia build up in blood
Ogilvie Syndrome
-AKA Acute Colonic Pseudo-obstruction (ACPO)
-Massive dilation of large intestine- electrolyte imbalances- older patients
-Tube in rectum to suck air out
-Stop opioid use
XRAY pic in slides
Projective vomiting in 2-6 week old = palpable “olive” mass, think of
Congenital pyloric stenosis
Bird’s beak on barium swallow, ? if from Chagas disease
Achalasia
Boerhaave syndrome
esophageal rupture
Diverticulosis vs. Diverticulitis - pain location and s/s
LLQ Pain, fever, leukocytosis
Intussusception (intestine collapses on itself) will present with
“currant jelly” stools
