Week 9

Malnutrition and dehydration, Aspiration pneumonia, poor QOL, weight loss

What are consequences of dysphagia?

Voluntary- oral preparatory and oral

Involuntary- pharyngeal and esophageal

What are the voluntary and involuntary steps in swallowing?

Inf/inflam- stomatitis, gingivitis, esophagitis

FB- string, bone and grass awn

Neoplastic- SCC

Trauma- electrical burns, mandibular fractures

Structural/congenital- stenosis or malformation. Cricopharyngeal achalasia, vascular ring anomaly

Metabolic- Oral ulcers stemming from CKD

Vascular- lingual thrombus

Neuromuscular dz- masticatory myositis, generalized polymyositis, botulism, rabies, myasthenia gravis

What are common ddx for dysphagia?

Decreased excretion of urea leads to increased urea in blood (uremia) → urea will accumulate in the saliva → Bacteria will convert it to ammonia → ulceration

How can CKD lead to oral ulcerations?

Structural: fractured bones and teeth

FN: string, granuloma, stricture

Inf: feline herpes and calicivirus

Infl: stomatitis, glossitis, and abscess

CS: dropping food, painful chewing, and excessive salivation

What are some oral and facial lesions that can cause dysphagia and what are common CS?

Granuloma and sialocele/ranula

What are some masses that can cause dysphagia that commonly affect the tongue?

Peripheral odontogenic fibromas and canine peripheral ameloblastomas

What are some masses that can cause dysphagia that commonly affect the gingiva?

SCC, melanoma and fibrosarcoma

What are examples of malignant tumors that can affect the oral cavity and cause dysphagia?

Sialdenitis is inflammation of one or more salivary glands

Sialadenosis is non-painful swelling of salivary glands

What is the difference between sialdenitis and sialadenosis?

A localized, fluid filled cavity under the skin or inside the mouth where leaked saliva has accumulated

What is a sialocele?

Parotid

What salivary gland sits right above the junction of the mandible to the skull?

Structural (rare)- elongated soft palate

Trauma- oropharyngeal penetrating trauma

Nasopharyngeal polyps

Nasopharyngeal stenosis

Functional: rabies, myasthenia gravis

Congenital: CA

What are pharynx related conditions that can cause dysphagia?

Obstruction: stricture, foreign body

Anatomical: diverticula, fistula

Infl: esophagitis

Functional: megasophagus

What are conditions of the esophagus that can cause dysphagia?

Trauma (choke chain)

edema

paralysis

What are conditions that can cause dysphagia that relate to the larynx?

FB

Gastroesophageal reflux disease

Drugs (doxycycline)

ingestion of irritant

Spirocerca lupi

CS: Regurgitation, extension of head and neck, ptyalism, repeated swalowing attempts, pain, depression, anorexia

What are causes to esophagitis? CS?

Atropine and acepromazine

What anesthetic drugs can cause gastroesophageal reflux ?

Endoscopy and esophogram

How to dx esophagitis?

Histamine receptor antagonists, proton pump inhibitors, cisapride, metoclopramide, amd sucralfate

How to treat GERD?

Nutrition: small frequent soft meal, soft fat and fibre

Pain management

gastronomy tube

What are supplemental tx for esophagitis?

Esophageal stricture

What can chronic esophagitis lead to?

Esophogram under fluoroscopy

How to dx esophageal stricture ?

Balloon catheter dilation, bougienage, stents, and surgical resection

What are some ways to tx esophageal stricture?

An immune mediated, paraneoplastic condition where antibodies are produced against the nicotinic Ach receptors

What is myasthenia gravis?

Flaccid tetraparesis and resp distress

What are signs of acute fulminant myasthenia gravis?

Presence of serum autoantibodies against Ach receptors

What is the gold standard dx of myasthenia gravis?

Chest rads, barium swallow study (risk for asp pneumonia), fluoroscopy, test for underlying disease

What are some ways to DX megasophagus?

Regurgitation, dysphagia, weight loss, asp pneumonia signs (nasal discharge, fever, cough)

What are CS to megasophagus?

GSD, Danes, Irish setter, and labs.

Vascular ring anomaly and incomplete nerve development

What breeds are predisposed to megasophagus and what are its causes?

Primary - idiopathic most common

Secondary- MG, stricture, hypothyroidism, hypoadrenocort, toxin

What are the primary and secondary acquired causes to megasophagus?

Protrusion of stomach through the esophageal hiatus of the diaphragm

What is a hiatal hernia?

Sliding/axial (most common)

rolling/ para-esophageal

What are two common types of hiatal hernias?

Temporal and masseter pain when opening and closing jaw, dysphagia, weight loss

What typical cs to masticatory myositis?

Hyperglobulinemia, anemia, and inc CK (acutely) and proteinuria

What is typical on blood work and urinalysis of a patient with masticatory myositis?

immunosuppression

How to tx masticatory myositis?

Cats have smooth muscle in the esophagus and it is not as affected as would a dog with skeletal muscle in their esophagus

Why do cats with myasthenia gravis don’t develop megasophagus ?

-otomy : Incision into

-ectomy : partial resection

-ostomy : creation of an opening into structure

What does the suffix -otomy, -ectomy, and -ostomy mean?

Lacks a serosal layer and leads to a slower deposition of fibrin during the healing process compared to other parts of the GI

What layer does the esophagus lack and what can this mean if surgery is performed?

Upper 2/3rd is striated muscle while lower 1/3 is smooth muscle

What is significant about the horse esophagus that will determine treatment?

Choke

What is an esophageal obstruction in large animals termed?

Ptyalism

What is the most common sign for esophageal disease in horseS?

A horse ingests a plant (often red clover, white clover, and alsike clover) infected with Slafractonia legumincola (fungi) that produces slaframine.

Slaframine will be metabolized to its active component that will stimulate the parasympathetic nervous system (muscarinic receptors) → salivary glands produce excess saliva

What is “slobbers” in horses ?

7

What cranial nerve could be damaged that can cause prehension deficits leading to dysphagia?

5, 7, and 12

What cranial nerve can be damaged that can cause issues with mastication in horses?

9 and 10

What cranial nerves can be damaged that can cause deficits to swallowing?

9, 10, and 12

What cranial nerves are located in the guttural pouch ?

Fungus (fungal mycosis)- erode arteries and cause profuse life threatening nose bleeds

What is the most dangerous pathogen that can affect the guttural pouch and what can it cause?

Frothy nasal discharge

Feed falling from nostrils and mouth

Ptyalism

gagging/retching

coughing

What are the clinical signs of choke in horses?

Sedation with xylazine and head tilted downward

What needs to be done before choke can be dx?

Endoscopy, passage of nasogastric tube, or ultrasound

What is used to dx choke in horses?

Buscopan (N-butylscopolammonium bromide)

What can be used to relax the lower third of the esophagus to allow easier dislodgment of material if choke is present there?

Oxytocin (NOT TO BE USED IF MARE IS PREG OR RECENTLY BRED)

What can be used to relax the upper two thirds of the esophagus to allow easier dislodgment of material if choke is present there?

Sedation + analgesia

Pass NG tube until resistance is felt

pump water in or use funnel and gently apply pressure to the obstruction

KEEP THE HEAD LOW to prevent aspiration of food into the trachea

Once choke is confirmed, what should one do?

24 -48 hrs after for the esophagus to heal. Should feed easily digestible feed like green grass

When should the horse resume feeding after choke is resolved?

Broad spec antibiotics, NSAID, sucralfate, and refeeding considerations

What can be done if the choke is prolonged for more than 48 hours?

Aspiration pneumonia, esophageal stricture (linear or circumferential) or esophageal rupture, megasophagus

What are some sequelae of choke?

Friesian

Megasophagus is rare in horses, but what breed is this a more common congenital issue?

Prolonged choke

What is a way for a horse to get an acquired megaophagus?

Muscular hypertrophy of caudal esophagus

What congenital issue causes megasophagus in friesian horses?