Week 2 - GI Flashcards
What does dyspahgia mean?
a SYMPTOM (not a diagnosis) - difficult/abnormal swallowing
What are the two classification of dysphagia?
- Oropharyngeal
-Oral
-Pharyngeal
-Cricopharyngeal (muscle related to upper esophageal sphincter/UES) - Esophageal - delayed
-exaggerated swallowing
Being a brachy sucks – why are they predisposed to dysphagia?
- stenotic nares
- elongated soft palate
- hypoplastic trachea
- inverted laryngeal sacules
How do brachycephalics get hiatal hernia?
bc they have a short muzzle > they have a mechanical obstruction in the upper airway (inspiratory stridor) > creates an increased negative intrathoracic pressure > this causes stomach to be sucked into chest cavity > weakness to diaphragm > hiatal hernia
When looking into dysphagia, which chem value should you look at?
CK!
and increased CK is not with Myasthenia Gravis
What is dysphonia?
-trouble talking/barking/meowing
caused by
neuropathy, junctionopathy, myopathy
How does anesthesia affect phagia?
-weakens LES tone (reflux can happen more easily)
-lose swallow reflex
What’s the difference between a video fluoroscopy and esophogram?
Esophogram
-giving contrast/barium by mouth – then taking radiograph right after
-2D dimensional image of esophagus
-document evidence of mechanical/anatomical defect in pharynx/esophagus
-single time point – can’t assess dynamics/motility
Video Fluoroscopy
-can assess dynamics/motility
-timing and opening of UES and LES
-can assess primary and secondary peristalsis
-assess reflux
-can assess everything from esophogram
What’s the Diagnostic Approach to the Dysphagic Dog?
- CT, MRI
- Electrodiagnostics (EMG, NCV) - helps with optimizing which muscle to biopsy
- Muscle biopsy
What are the muscles of mastication?
- pterygoid
- temporalis
- masseter
- digastric
What is MMM?
Masticatory Muscle Myositis
-autoimmune disease - dog’s immune system identifies the dog’s own muscle tissue as foreign and attacks it
-Inability to open the jaw under GA is a classical finding
-Usually bilateral
-Dobermans, Labradors, GSD, Rottweilers, Siberian husky, CKCS
What are some ways to DIAGNOSE MMM?
-CK may or may not be elevated! (acute yes, but could be normal if chronic)
-Serological assays: 2M antibody (ELISA)
–negative 2M doesn’t rule out MMM
-immunocytochemistry - false negatives if given corticosteroids within week
-Muscle biopsy - helps with diagnosis & long-term prognosis
What are the 2 types of Cricopharyngeal Muscle Dysphagia?
- Achalasia - Failure of cricopharyngeal muscle (CPm) to completely relax or open
-Idiopathic hypertrophy of the CPm
-there can also be LES Achalasia (achalasia is not sphincter specific) - Asynchrony - Inappropriate timing in opening of UES
-Idiopathic - thought to be a neuropathy
-UES does open, just at the wrong time
What are CS of Cricopharyngeal Muscle Dysphagia?
-Dysphagia within seconds of swallowing
-Repeated swallowing attempts
-Dysphagia usually worse with water
-Nasal reflux
-Coughing
-Bloating
What is the opening to the UES?
Cricopharyngeal bar
How do you TREAT Cricopharyngeal Muscle Dysphagia?
- open surgical myotomy - PREFERRED
-take out entire cricopharyngeal - Closed CO2 laser myotomy
-expensive, need special equipment - Botox injection of CP muscle - temp
-Botox causes temporary weakness of the CP muscle
-15 Units injected in 3 sites directly in the CP muscle
-Application of Botulinum Toxin - Balloon dilation of UES - temp
- Enteral feeding device - temp
What is Megaesophagus?
generalized loss of motor function to the esophagus results in dilation and loss of normal peristaltic motility. result - food and fluid accumulate in esophagus
Myasthenia Gravis is seen in ____% of all Megaesophagus cases
25%
Esophageal Achalasia occurs in about ___% of dogs with Megaesophagus
70%
Megaesophagus can be congenital/primary (idiopathic) OR acquired form: primary (idiopathic) or secondary to underlying disease
Congenital/Primary Idiopathic ME: puppies at weaning
Acquired/Primary Idiopathic or Secondary to underlying dz: myasthenia graves, SLE, polymyositis, polymyopathies, dermatomyositis, Addison’s. Esophageal obstructive diseases, if they’re chronic enough.
Acquired idiopathic of ME is most common in dog - German shepherd, Great Dane, Irish Setter
In terms of congenital megaesophagus…
-Never see focal megaesophagus alone with congenital myasthenia gravis
-will see focal MEGAESOPHAGUS + systemic weakness in a young puppy with MYASTHENIA GRAVIS
-will commonly see puppies with CONGENITAL MEGAESOPHAGUS without MYASTHENIA GRAVIS
There is 2 forms of Myasthenia Gravis
- Congenital - rare, NOT AUTOIMMUNE
-no need to draw blood for testing for antibodies bc not autoimmune - Acquired - autoimmune
-40% of cases only have focal ME without systemic weakness
-45% of cases have severe ME with systemic weakness
How can you DIAGNOSE Myasthenia Gravis?
- Acetylcholine Receptor Antibodies – if suspecting autoimmune MG
-normal is <0.6
-may be normal still if acute onset
How do you MANAGE Idiopathic Megaesophagus?
- Modify consistency of the diet and water
- Feed from elevated position
-Bailey Chair - Gastrostomy feeding tubes