Large Animal GI - Exam 1: Organs and Tubas

What can you use for a more thorough oral exam?

An endoscope

What is an important part of the legal medical record, ensures consistency in exams, and increases the perceived value for the client?

Dental charting

At what age do you switch from oral exams every 6 months to annually?

4 years old

At what age should you consider switching oral exams back to every 6 months?

18 years or older

How do masticatory patterns change depending on roughage versus grain diets?

Roughage is more lateral mastication, while grain is more vertical crushing

What is a negative consequence of painful oral disorders on the teeth?

It can change mastication, which influences wear patterns

Where are the "points" on the cheek teeth?

Buccal surface of maxillary teeth,

Lingual surface of mandibular teeth

(Feel your own teeth with your tongue. Which set is easier to feel, bottom or top?)

What is the most commonly performed oral surgical procedure?

Exodontia

What is the painful, progressive condition in older horses that affects the canine and incisors, characterized by odontoclastic resorption and proliferation of cementum?

Equine odontoclastic tooth resorption and hypercementosis (EOTRH)

Which cheek teeth are more likely to fracture?

Maxillary teeth (~80% of cases)

Regarding maxillary apical cheek teeth infections, which group of teeth are more likely to have external swelling?

06 - 08 (~85%)

Regarding maxillary apical cheek teeth infections, which group of teeth are more likely to have sinus involvement?

09 - 11 (~95%)

What are the steps to a standing oral extraction?

Patient preparation (drugs, speculum),

ID tooth (exam, rads),

Elevate gingiva (separate from crown),

Disrupt periodontal ligament (gradual, steady pressure),

Fulcrum (controlled rotation), and

Sectioning (if can't be removed whole)

What is an alternative method or oral extraction for cheek teeth?

Minimally Invasive Transbuccal Screw Extraction

The non-specific term for discomfort in a horse, commonly due to abdominal pain, is what?

Colic

T/F: The order of the components of the colic exam matter

TRUE

What are the components of the colic exam in order?

History (unless distressed),

Physical exam (unless gonna explode),

Nasogastric tube (if high HR),

Transrectal palpation,

Ultrasound (FLASH),

Abdominocentesis (etiology), and

Other (blood, endoscope, etc.)

What are the six perfusion parameters?

Mentation,

MM color,

CRT,

Pulse rate,

Pulse quality, and

Extremity temperature

T/F: Nasogastric intubation is a therapeutic tool, not a diagnostic one

False, it is both

What are the diagnostic characteristics of NG intubation?

Significant reflux indicates small intestinal obstruction, and can diagnose esophageal obstruction

What are the therapeutic characteristics of NG intubation?

Prevents gastric rupture by relieving pressure,

Can unblock esophageal obstruction, and

Can be used to administer medication

What are the indications for immediate NG intubation?

Actively painful or over 60 bpm

What is a major requirement any time you place an NG tube?

Confirming you are in the esophagus by SIGHT and TOUCH

T/F: Negative pressure is a reliable way to tell if you are in the esophagus

False

T/F: You should ship a refluxing horse with an NG tube

True

What are the two most common complications with NG tubes?

Giving meds in the lungs, and

Giving unsafe meds

You need two of the items from what list before performing transrectal abdominal palpation (TRAP)?

Standing chemical restraint,

Stocks,

Twitch,

Epidural, or

Buscopan

What are the two primary indications for TRAP?

Colic and reproductive

What might make you reconsider performing a TRAP?

If the safety risk outweighs the necessity, such as small/young, straining horses or friable mucosa from colitis

(If you have an unstocked, unmedicated stallion with minor diarrhea, maybe skip this one)

Tell whether the following structures are palpable or not:

1. Spleen

2. Nephrosplenic ligament

3. Left kidney

1. Yes

2. Yes

3. Yes

Tell whether the following structures are palpable or not:

1. Small colon

2. Aorta

3. Right kidney

1. Yes

2. Yes

3. No

Tell whether the following structures are palpable or not:

1. Duodenum

2. Cecum

3. Right dorsal colon

1. No

2. Yes

3. No

Tell whether the following structures are palpable or not:

1. Right ventral colon

2. Ileum

3. Jejunum

1. No

2. No

3. No

Tell whether the following structures are palpable or not:

1. Left ventral colon

2. Pelvic flexure

3. Left dorsal colon

1. Yes

2. Yes

3. Yes

What are the female reproductive organs that are palpable?

Uterus and ovaries

What are the male reproductive organs that are palpable?

Internal inguinal rings and accessory sex glands

T/F: You should mix up your ultrasound exam depending on the sex of the horse

False, always have the same approach

What does FLASH stand for?

Fast Localized Abdominal Sonography of Horses

What is ultrasonography assessing for?

Free peritoneal fluid,

Motility of bowel segments,

Distension of bowel, and

Wall thickening

The collection of peritoneal fluid by puncture is called what?

Abdominocentesis

What are the parts of the standard fluid analysis?

Gross (color, turbidity),

Cytology, and

Total protein

What are the characteristics of a normal fluid analysis?

Strong yellow color,

Not turbid,

<2000 nucleated cells, and

<2.0 g/dL of protein

What fatal condition in horses can be diagnosed with abdominocentesis?

Ruptured GI viscus

What are the large strongyle species?

S. vulgaris,

S. edentatus, and

S. equinus

Most large strongyles migrate to the liver. Which one migrates to the cranial mesenteric artery?

S. vulgaris

What is the other name for small strongyles?

Cyathostomes

What is the pathology associated with cyathostomes?

Intestinal wall inflammation and thickening

What unique ability of cyathostomes makes diagnosis difficult?

They encyst from L3 to L4, meaning you can't rely on FEC for diagnosis

What is the species of equine roundworm?

Parascaris equorum

When should you suspect equine roundworms?

Colic due to non-strangulating small intestinal obstruction

What is the primary equine tapeworm?

Anoplocephala perfoliata

What anatomical structure is often affected by equine tapeworms?

Ileocecal valve

What is the equine pinworm?

Oxyuris equi

What are the clinical implications of the equine pinworm?

Eggs are deposited around the anus and tail-head, making it itchy

What is the equine bot fly genus?

Gasterophilus

What is the clinical significance of equine bot flies?

Eh, just tells you that your dewormer sucks

What is the equine lunworm?

Dictyocaulus arnfieldi

T/F: Horses are the natural host for D. arnfieldi

False, donkeys are, so infected horses must be around donkeys

What is the clinical sign of equine lungworm?

Parasitic bronchitis

T/F: There is evidence for natural anthelmintic treatment

False

What is the mechanism of action for benzimidazoles?

Interfere with parasite metabolism

What is the mechanism of action for pyrimidines?

Paralyzes the parasite

What is the mechanism of action for macrocyclic lactones?

Disrupts the parasite's neuromuscular activity

What is the mechanism of action for isoquinolones?

Impairs the suckers and stimulates motility

What group of dewormers has less resistance than the others?

Macrocyclic lactones

What are the two effective treatments for tapeworms?

Pyrantel pamoate and praziquantel

What are the two effective treatments for cyathostomes?

Fendbendazole and moxidectin

What pyrimidine should be avoided due to it's promotion of resistance?

Pyrantel tartrate

What group of drugs is often paired with praziquantel to kill tapeworms?

Macrocyclic lactones

What is the contraindication for moxidectin?

Young/small and debilitated horses due to its neurologic effects

What are the goals of parasite control?

1. Limit, not eliminate, infection

2. Minimize disease risk

3. Target environment

4. Prevent resistance

What are the things that should be considered when deciding to deworm a horse?

Base on FEC (Test),

Base on signalment and signs (Think), and

Tailor to specific parasite (Target)

What is the function of the McMaster FEC?

Determine the shedding status,

Evaluate dewormer efficacy, and

Determine parasite type

What are the limitations of the McMaster FEC?

Does not reflect adult burden,

Does not detect larvae/encysted,

Does not detect tapeworms, and

Does not detect pinworms

What are the indications of the McMaster FEC?

1-2 times per year and on new additions

What FEC values indicate deworming is necessary?

High shedders >500 epg

What are the horse considerations for parasite control programs?

Age,

Reproductive status,

Signs, and

Herd size

What characteristic of the esophagus makes surgical healing complicated?

No serosal layer, meaning no fibrin seal, and increased tension from swallowing

What is the main pathogenesis of esophageal disease that causes signs?

Retention of feed/saliva in the esophagus

What are the clinical signs of esophageal disease?

Increased salivation,

Nasal discharge, and

Focal swelling

What disease process gives similar signs to esophageal diseaes?

Dysphagia (can't swallow)

T/F: Esophageal disease is common in nursing foals

False

What is the most useful diagnostic tool for esophageal disease?

Endoscopy

What is the limitation of ultrasound versus radiography?

Ultrasound can only view the cervical esophagus

What radiographic technique is ideal for visualizing mucosal detail?

Double contrast esophagram (barium + air)

When is contrast radiography contraindicated?

Suspected perforation or increased risk of aspiration pneumonia

What esophageal disease is a common medical emergency?

Choke

What is a major predisposing factor to choke?

Dental problems with age

What are the four common sites of choke?

Post pharyngeal,

Thoracic inlet,

Base of heart, and

Terminal esophagus

What are the diagnostic modalities for choke?

NGT with sedation, and

Endoscopy

T/F: Owners should give nothing by mouth until evaluated if choke is suspected

True

What are the goals of treatment for uncomplicated choke?

Lower head,

Reduce anxiety, and

Dislodge obstruction

What is the treatment of uncomplicated choke?

Sedation and NGT with lavage

What is the procedure involved in treating complicated choke?

Endoscopy (definitive diagnosis),

NGT + lavage,

Pharmacologic therapy, and

Supportive care

What is the last resort for treatment of choke?

Esophagotomy

What are the most common complications associated with choke?

Dehydration (no water),

Electrolyte abnormalities (no water),

Aspiration pneumonia (reflux),

Re-obstruction (damage), and

Mucosal ulceration (damage)

What is the main cause of esophageal stricture?

Obstruction causing circumferential ulceration

What is the FIRST treatment of esophageal stricture?

Medical management, especially if acute (<2 weeks)

What area of the esophagus is most commonly perforated?

Cervical esophagus

What are the common causes of perforation?

Prolonged obstruction and trauma