GI System - Upper and stomach Flashcards
What is the purpose of the circular and longitudinal muscles of the pharynx?
Circular - constrict to push food into esophagus (bolus formation)
Longitudinal - lifts the walls of the pharynx during swallowing
What are the phases of swallowing and what nerves are involved?
Oral: pre-hend food and form bolus which moves to end of tongue (CN trigeminal V, facial VII, hypoglossal 12)
Pharyngeal: propel bolus along pharynx, closure of larynx by epiglottis and inhibition of breathing, opening of UES by cricopharyngeal m. (CN glossopharyngeal IX and accessory XI)
Esophageal: bolus moves along esophagus into stomach (CN glossopharyngeal IX and vagus X)
Your patient presents for dysphagia..
What are your top DDX?
Congenital - cricopharygnealachalasia or esophageal dysmotility
Neuromuscular - myasthenia gravis or brainstem lesions
Myopathy/myositis
Neoplastic or paraneoplasic
Infectious (uncommon)
- viral distemper or rabies
- bacterial abscess
- spirocera lupi
The main presenting complaint in your patient is dysphagia… what diagnostics would you do to find the cause?
Physical exam - watch patient eat and drink
Neurologic assessment — assess GAG or pharyngeal reflex (CN 9 and 10)
Assess pulmonary — aspiration pneumonia
Thin muscling of head — MMM (titers)
Nutrition status
MDB +/- thyroid Radiographs Fluoroscopy Acetylcholineseerase receptor antibody titer — MG Upper GI endoscopy MRI for brain stem lesions
What is the general management for dogs with pharyngeal disease?
Food and water consistency —> variable amongst patients (slurry vs meatballs vs solid food)
Elevate food and water dishes
Some need feeding tubes
Monitor for pneumonia
No neck leads —> use harness
What type of muscle makes up the esophagus in dogs and cats?
Dog - entire length is striated
Cat - distal aspect is smooth muscle
What are the layers of the esophagus
Epithelium Basement membrane Laminate propria Muscularis mucous Submucosa Muscularis propria Adventitia
What diagnostics can determine the presence of foreign body or compressive lesions?
Barium mixed with water or food (careful of aspiration)
Lohexol - injectable contrast agent
What diagnostic method can you use to evaluate swallowing phases and peristalsis?
Fluoroscopy
What is esophagitis?
Inflammation of the esophageal mucosa (can affect motility)
What are causes of esophagitis?
Secondary to meds (eg doxycycline)
Foreign bodies
Caustic toxins
Gastrointestinal reflux (GERD)
General anesthesia
Primary GI disease
What could you see with rads and endoscopy that indicates esophagitis?
Rads : unremarkable or a mild transient dilation
Endoscopy: erythema +/- edematous mucosa +/- ulcer or erosions
What is the treatment for esophagitis?
Pain management
- buprenorphine, codeine, fentanyl
- magic mouthwash = lidocaine, diphenhydramine, maalox
Mucosal protection
- sucralfate/carapace
- antacid (omeprazole PPI)
Monitor for strictures
Look for underlying dz
What are causes of esophageal stricture?
Trauma Neoplasia Post-foreign body Post-anesthesia Severe esophagitis
Treatment fo esophageal stricture?
Balloon catheterization — breakdown stricture
Esophageal diverticulae are secondary to??
Trauma
Congenital abnormalities (PRAA)
What is the treatment for esophageal diverticulae?
Clear impaction
Surgery
What is myasthenia gravis?
Antibody production against acetylcholine receptions at NM junction
Congenital or acquired megaesophagus
T/F: it is possible for congenital megaeosphagus to improve over time
True
What breeds do we see congenital megaesophagus in?
SharPei, fox terrier, German shepherd, lab, Great Dane, Irish setters, mini schnauzer, Newfie, and Siamese cats
<6months
What are causes of acquired megaesophagus?
Idiopathic
Primary CNS - brainstem lesion
Primary neuromuscular disease
Neoplastic syndrome ( thymoma)
Endocrine association
- hypothyroidism
- Addison’s disease
Lead toxicity (hunting or fishing dogs- evidence on blood work) LES stricture / dysfunction
What is the treatment of MG?
Underlying disease and symptoms
Nutritional support +/- feeding tubes
Decrease risk of aspiration pneumonia and treat PRN
Variable food consistency
- smaller more frequent meals
- elevated food dishes
What is the prognosis for megaesophagus ?
Fair to good when patients tolerated interventions or feeding tubes
Guarded to poor
- fulminant MG crisis
- severe aspiration pneumonia
- intractable regurg
What is the connection between the stomach and esophagus and prevents food from passing back?
Cardiac/esophageal sphincter
What is the connection between the stomach and duodenum?
Pyloric sphincter
What do you call food in the area of the duodenum that is a semi-solid, soapy mixture?
Chyme
What gastric juices are secreted into the stomach?
HCl Salts Enzymes Water Mucous
What are the layers of the stomach?
Gastric mucosa made of gastric glands and muscularis mucosae
Submucosa
Meissners plexus
Muscularis (3layers)
Auerbach (myenteric) plexus
Serosa
What are signals innervate the enteric nervous system?
Can function autonomously (sensory receptors, primary afferent, internurons, and motor neurons)
Also receives PSNS and SNS innervation from the central nervous system
Where is gastrin produced?
Gastric antrum, duodenum, and pancrease
What are the main physiologic actions of gastrin?
Simulate secretion of gastric acid and intrinsic factor from parietal cells
Simulate secretion of pepsinogen from chief cells
Promote gastric and intestinal motility, mucosal growth
Where is somatostatin produced?
Stomach, intestine, and pancreas (D cells)
What is the main physiologic action of somatostatin?
Inhibit the secretion and action of many hormones, including Gastrin Cholecystokinin Secretin Vasoactive intestinal peptide Gastric inhibitory polypeptide Motilin
What are the components of the mucosa of the stomach?
Superficial epithelium
Laminate propria -> loose CT, immune system cells, and nutritional support
Gastric glands -> mucous neck cells, parietal cells (HCl), and chief cells (digestion)
Neuroendocrine cells
- enterocromafin -> serotonin, histamine
- somatostatin
- gastrin
Muscularis mucosa - thin muscle layer
Most intrinsic factor in dogs comes from the ____________ and is essential for absorption of what nutrient?
Pancreas
B12 (cobalmin) absorption
What enzymes in the stomach contribute to protein and fat digestion
Pepsin - protein
Gastric lipase - fat
How does fatty food affect the motility of the stomach?
Slows movement
What clinical sign can help differentiate between esophageal disease and stomach disease?
Vomiting —> stomach disease
Regurgitation —> esophageal disease
What is acute gastritis?
Inflammation of the stomach
- sudden onset
What are causes of acute gastritis?
Drug, toxins Dietary indiscretion or intolerance Parasites Bacterial Viral Systemic illness
How can you diagnose acute gastritis?
Based on history and clinical findings —> trial response to symptomatic care if not systemically ill
If clinical signs persist or systemically ill —> biopsy
Treatment for acute gastritis?
Fluids
Antacids
Anti-emetics — once foreign body rule out or vomiting is protracted/severe enough to cause dehydration or electrolyte imbalances
Pain meds
Water and bland diet
What is the diagnosis and treatment for gastric foreign body?
Based on history and clinical signs —> obstructive lesion has intermittent or persistent clinical signs
RADS
More common in young animals
Surgery or endoscopy
How can you diagnose food bloat?
Acute vomiting or fetching along with abdominal distention or discomfort
Rads— gas distended stomach
Treatment for food bloat?
Time - 24 to 36hours
Fluids Withhold food Walk frequently Pain managment \+/- lavage \+/- surgery
Gastric ulcers arise from mucosal barrier injury.. what are the types of these injuries?
Disruption of normal gastroprotection
Decreased blood flow
Hyper-secretion of acid
Decreased mucous or bicarb
Mucosal barrier injury leading to gastric erosion and ulcers can be secondary to what causes?
Neoplasia: gastrinoma, MCT, other hypovolemic shock, hypotension
Trauma, foreign bodies
Medications: NSAID or steroid
Uremic gastritis
Clinical signs associated with gastic erosion and ulcers?
\+/- vomiting Hematemesis Melena Retch Inappetence Weak
What diagnostics would you do if you suspected gastric uclers and what would you expect to find?
CBC/biochem : anemia, elevated BUN
Rads- defects may be seen with contrast
UA- protein loss? R/O renal disease causing a gastric uremia
Ultrasound +/- thickened wall or focal looks of layers/free fluid
** endoscopy - visual confirmation and biopsy
What is the treatment for gastric erosion/ulceration?
Treat primary dz
Mucosal protection —> sucralfate, proton pump inhibitor (omeprazole)
Pain management
Blood transfusion
Nutrition
What treatment options can you use for helicobacer gastritis?
Antibiotics — amoxicillin / tetracycline / erythromycin / flagyl
Antacids — omeprazole / Pepcid AC
Pepto-bismol - accumulates in cell wall and destroys helicobacter
Common roundworms found in dog stomach?
Toxocara canis
What is the treatment for toxocara ?
Fenbendazole or paraneoplasic palmate
Stomach worm of canines and felines? How can each be diagnosed?
Round worms (toxocara canis/cati) - visualize or fecal
Physalloptera - difficult to float but 2-6cm worms can be seen on endoscopy
Feline — ollulanus tricuspsi - biopsy, gastric juice evaluation, vomitus evaluation
How can physalloptera be treated?
Pyrantel pamoate
How do you treate ollulanus tricuspsi?
Fenbendazole
You have chronic vomiting in your dog.. you do endoscopy and see a thickened gastric outflow tract and masses which biopsy shows to be pyogranulomatous inflammation What would be on your Dx?
Pythiosis
Oomycete - P. Insidiosum
What is the treatment and prognosis for pythiosis?
Pythiosis vaccine (preventative)
Terbinafine and itraconazole antifungals
surgery — wide margins required
High fatality ate
Clinical signs associated with gastroesophageal reflux?
Chronic vomiting or regurgitation
Lip licking, hard swallow, ptyalism, esophagitis
How do you treat gastroesophageal reflux?
Sucralfate and proton pump inhibitor
Treat primary disease
How can you diagnose inflammatory gastritis?
Endoscopy / surgical biopsy — infiltrate of inflammatory cells (lymphoplasmacytic, also eosinophilic and mast cells) in mucosa and lamina propria
You suspect an inflammatory gastritis but are waiting for your biopsy to confirm… how do you treat in the meantime?
Symptomatic therapy
Antacid/gastorprotectant
Antiemetics
Empirical deworming — fenbendazole and pyrantel pamoate
Diet trial with hypoallergenic or novel protein diet
Biopsy confirms inflammatory gastritis… how do you treat?
Immune modulation
Prednisone (dog)/ Prednisolone (cat)
Cyclosporine or atopica
Mycophenolate
Azathioprine
Chlorambucil
Your patient has atrophic gastritis… what happens if the inflammation is not treated?
Chronic vomiting
Marked mononuclear (lymphocytes, macrophages)
Thinning of gastric mucosa
Atrophy of gastric glands
How is atrophic gastritis treated??
Same also other inflammatory dz..
Immune modulation
Prednisone (dog)/ Prednisolone (cat)
Cyclosporine or atopica
Mycophenolate
Azathioprine
Chlorambucil
Clinical signs associated with hypertrophic gastropathy?
Chronic vomiting — hours after earring
What are causes of of hypertrophic gastropathy?
Inflammatory infiltrates
Hypergastrinemic conditions
- decreased clearance from renal or liver dz
- gastrin secreting tumor
Breeds associated with hypertrophic gastropathy?
Older, small breeds
Therapy for hypertrophic gastropathy?
Treat underlying dz
Surgical resection of thickened tissue
Congenital pyloric stenosis/hypertrophy is see in what breeds?
Boxer, Boston terrier, English bulldog, and Siamese cats
Clinical signs of pyloric stenosis/hypertrophy?
Vomiting several hours after meal — delayed gastric emptying (rads) Weight gain Aspiration pneumonia Depression Dehydration
Acquired causes of pyloric stenosis?
Inflammation
Neoplasia (gastrinoma)
What is Zollinger-Ellison syndrome?
Gastrinoma— gastrin secreting tumor
Chronic vomiting
Thickened gastric wall, hypertrophy of pyloris, gastric ulceration
Reflux esophagitis
+/- diarrhea
Where are gastrinoma tumors usually located?
Pancreas
How can you diagnose a gastrinoma?
Gastrin level assessment
Low pH of gastric juice + high level of gastrin
US/CT scan
Scintigraphy
Biopsy
Treatment of a gastrinoma?
Surgical removal of tumor (often has mets)
PPI- high dose
Octreotide — inhibits gastrin
DDX for stomach neoplasia?
Leiomyoma/leiomyosarcoma
Adenomatous polyps
- *Adenocarcinoma (DOG)
- *LSA (CAT)
How do you diagnose bilious vomiting syndrome ?
Early morning bile vomiting
Usually young dogs
Caused by reflux of duodenal fluid into stomach and irritation of GI mucosa
Treatment of Bilioius vomiting syndrome?
Frequent small feedings
Prokinetic
Gastroprotectants
Novel protein diet
