Equine GI disease pt 1

Question 1

horse stomach capacity and location
- can we see abdominal distension with dilation of the stomach?

Answer 1

Stomach: capacity of 4- 5 gallons
- Completely enclosed by the rib cage, thus will not see abdominal distension with dilation of the stomach.

Question 2

horse small intestine length, diameter
- location
- how long is the mesentery for each part?

Answer 2

A. Average length of 22 metres (70 feet)
B. Average diameter is 3.5 to 4.0 cm - 6 to 7.0 cm when become stretched
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C. Separated in 3 segments:
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1. Duodenum
a. Originates on the right side of the abdomen
b. Descending portion closely associated with the right lobe of the liver, the right dorsal colon and the right kidney
c. Mesoduodenum is short (fixed). At the last rib the duodenum turns towards the midline, then becomes jejunum
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2. Jejunum
a. Suspended by a long mesentery - up to 50 cm in length at the distal aspect of the jejunum
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3. Ileum
a. About 2 feet long
b. Differentiate by a fold of tissue at the anti mesenteric side that becomes continuous with the dorsal tenial band of cecum as the ileocecal fold

Question 3

horse LI length

Answer 3

A. Cecum to anus 7 - 8 metres

Question 4

horse large intestine components

Answer 4

Separated into cecum, large colon, and small colon

Question 5

cecum shape, orientation
- bands
- folds
- haustra?
- connection

Answer 5

a. Comma shaped, apex running forward along the abdominal floor
b. 4 tenial bands* (lateral, dorsal, medial and ventral)
(1) Ileocecal fold continuous with the dorsal band of cecum on the lesser curvature and the anti-mesenteric band of the ileum
(2) Cecocolic fold arises from the lateral cecal band and attaches to the lateral free band of the RVC
c. Presence of haustra**
d. Base attached dorsally by connective tissue to the abdominal wall

Question 6

horse large colon
- components
> bands
> haustra?
> location

Answer 6

a. Right ventral colon (RVC)
(1) Diameter of 20-25 cm
(2) 4 tenial bands (Lateral and medial free bands, lateral and medial bands)
(3) Presence of haustra
(4) End at sternal flexure
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b. Left ventral colon (LVC)
(1) Diameter of 20-25 cm
(2) 4 tenial bands (Lateral and medial free bands, lateral and medial bands)
(3) Presence of haustra
(4) End at pelvic flexure (8-9 cm)
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c. Left dorsal colon (LDC)
(1) 1 tenial band (mesenteric)
(2) End at diaphragmatic flexure
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d. Right dorsal colon (RDC)
(1) Up to 50 cm
(2) 3 tenial bands
(3) End at transverse colon
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e. Transverse colon - 8 cm in diameter

Question 7

horse small colon length, location, bands, haustra?

Answer 7

a. Approximately 3 metres in length
b. The coils are mingled with those of the small intestines
c. 2 tenial bands (mesenteric and anti mesenteric)
d. Presence of haustra

Question 8

what are tenia and haustra?

Answer 8

Tenia: longitudinal bands of muscle

Haustra: sacculations of the bowel found at the level of the cecum, RVC, RDC and small colon

Question 9

what is colic? divided into what broad types?

Answer 9

A. General term describing several conditions with symptom of abdominal pain
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B. Divided into:
1. True Colic pain originating from the digestive tract
2. False Colic originating from elsewhere

Question 10

Differential Diagnosis (false colic) must include:

Answer 10

A. Reproductive problem
1. Mares in Heat
2. Advancing Pregnancy
3. Rupture of the middle uterine artery
4. Ruptured ovarian granulosa cell tumour
5. Uterine Torsion
6. Breeding Injuries
a. Vaginal Tear
b. Rectal Perforation
7. Testicular Torsion
8. Thrombosis of Testicular Artery
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B. Urinary tract disease
1. Urinary calculi
2. Kidney Disease

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C. Liver disease
1. Cholelithiasis
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D. Haemorrhagic Shock
1. Rupture of a cranial mesenteric aneurysm
2. Splenic rupture
3. External hemorrhage
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E. Respiratory problem
1. Pleuritis
2. Acute exacerbation of respiratory obstructive disease
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F. Others
1. Tetanus
2. Laminitis
3. Rabies
4. Grass Sickness
5. Myositis

Question 11

mild colic clinical signs

Answer 11

• Mild colic signs: anorexia, depression, teeth grinding, yawning
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  1. Yawning
  2. Extended neck stretching of upper lip in flehmen like response
  3. Teeth grinding
  4. Anxiety in the eyes
  5. Looking at flanks with ears pinned back
  6. Dullness and depression
  7. Groaning

Question 12

moderate colic clinical signs

Answer 12

• Moderate colic signs: looking at flanks, pawing, groaning, muscle tremor, frequent small urination, rolling
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  1. Pawing at the ground with front feet
  2. Lashing out with hind legs
  3. Muscle tremors particularly in hot blooded horses
  4. Patchy sweating
  5. Frequent posturing to urinate but passing only small amounts
  6. May want to lean against the wall or lie on the ground
  7. Rolling
  8. Resting in unnatural positions, on back or dog sitting with forelegs extended.
  9. May have abnormal feces, diarrhea, foul smelling, or hard and dry

Question 13

severe colic signs

Answer 13

• Severe colic signs: violent rolling, kicking at belly, crash to the ground, abdominal
  distension, might attempt to vomit
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  1. As with moderate but more severe
  2. Pain usually continuous
  3. Violent rolling, kicking at belly
  4. Flip laterally and crash to the ground (up and down)
  5. Total disregard for self or handlers
  6. Traumatise self the head on the supraorbital process, lower legs and the hocks
  7. Sweating, generalised, will steam and drip sweat from under belly continuously
  8. Distended abdomen
  9. Laboured breathing
  10. Might attempt to vomit appearance of greenish discharge at the nostrils, not at the mouth
  11. Rolling on its back  relief by taking the tension off the mesentery

Question 14

What to do in case of colic?
- broadly, what are our options / things we should consider?

Answer 14

A. Prevention of further damage
B. Take a good history
C. Observe
D. Physical examination
E. Per rectum examination
F. Nasogastric intubation
G. Abdominal paracenthesis-abdominocenthesis
H. Laboratory Tests
I. Trocharization of the large bowel
J. Imaging techniques

Question 15

how to prevent further damage in the case of a colic, before doing anything else?
- what can violent rolling cause?

Answer 15

1. If animal rolling violently may cause
   a. Rupture of an internal organ
   b. Fracture of spinous processes of the withers
   c. Produce an organ displacement or volvulus

Question 16

how to prevent further damage in the case of a colic, before doing anything else?
- suggestions to avoid injury

Answer 16

2. To avoid injury, you may suggest
   a. Walk the horse
   b. Off feed
   c. Do not administer home remedies
   d. DO NOT GET HURT
   e. Bandage lower legs
   f. If in a stall, get into an arena or outside onto pasture

Question 17

how to prevent further damage in the case of a colic, before doing anything else?
- initiate therapy in severe cases? what to do?

Answer 17

3. Severe cases may need to initiate therapy immediately
   a. Presence of ingesta at the external nares - get a nasogastric tube in!
   b. Violent colic - may need to administer analgesics > take a heart rate before

Question 18

what to investigate when you take a history for a colic case?

Answer 18

• Signalment
• Duration and nature of the colic signs
• Passage of feces? consistency?
• Diet, availability of water
• Previous colic?
• Worming history
• History of medical treatment (NSAID)
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  1. When?
  2. Nature of colicky signs
  a. Acute Vs chronic
  b. Progression?
  3. Passage and nature of feces (mucus)
  4. Age of animal
  5. Anorexia? Water access?
  6. Diet? Recent change? (new oats, fresh hay, or apples producing rapid fermentation)
  7. Worming history
  8. History of previous colic
  9. Vaccination history
  10. Regular dental care
  11. Any accident, injury, or recent infections, e.g. diaphragmatic hernia, rent in mesentery, malignant edema
  12. Sex
  a. Mare history of recent breeding, pregnant?
  b. Male inguinal hernia
  13. Previous abdominal surgery (adhesions) - Palpate the midline
  14. History of medical treatment (NSAID intoxication)

Question 19

what to observe for in a colic case as soon as you arrive?

Answer 19

Observe the horse and environment:
* are these signs typical of abdominal pain?
* severity of signs
* abdominal distension
* signs of injury
* look at the environment
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1. Look at stall or surroundings for signs of damage, pawing, pacing, rolling…
2. Position of the ears
3. Is the horse depressed, or alert?
4. Self induced trauma? (wounds on the eyelid…)
5. Abdominal distention
a. large bowel > most likely viscera producing a noticeable enlargement of the abdomen

Question 20

what parameters should we look at for a physical exam during a colic call

Answer 20

1. pulse
   - rate
   - quality
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2. temp
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3. cardiovascular signs
   - mucous membranes: colour, CRT
   - skin
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4. respiratory system
   - rate
   - chest auscultation
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5. auscultation of the abdomen
   - motility, typmany
   > evaluate four quadrants
   > percussion
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6. reproductive system
   - stallion > palpation of scrotum

Question 21

what is a normal heart rate for a horse? what rates indicate medical problems?
- when might we need an ex-lap?

Answer 21

(1) 36 beats/min  normal
(2) 40-60 beats/min  usually medical problem
(3) 60-80 beats/min  may need exploratory laparotomy
(4) 80-100 beats/min  likely needs an exploratory laparotomy
(5) >100 beats/min  very serious

Question 22

how does pulse quality relate to prognosis for a colic?

Answer 22

(1) Stronger the pulse the better the prognosis
(2) Weak irregular pulse indicates a failing heart (metabolic acidosis, endotoxic shock)

Question 23

when should we take our rectal temp for a colic call?
- what does an increased temp indicate? decreased?

Answer 23

a. Take temperature before performing a per rectum examination
b. Colic with acute pain may have a slight elevation
c. +/- increased with peritonitis or infectious diarrhea
d. Temperature subnormal with shock

Question 24

what are we looking for when we examine the skin during a PE for colic?
- sweating
- extremeties
- resiliency

Answer 24

(1) Sweating > severe pain or rupture
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(2) Feel extremities for uneven temperature distribution
(a) if cold > shock with vasoconstriction
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(3) Skin resiliency test
(a) rough guide to assess total body hydration
(b) skin on the side of the neck good place, upper eyelids not good

Question 25

why might we observe an increased resp rate in a colic physical exam?

Answer 25

(1) May be increased due to pain
(2) Increased > gastrointestinal distension

Question 26

when we auscultate the abdomen for a colic PE, what is our general strategy?

Answer 26

a. Evaluate four quadrants (right dorsal and ventral, left dorsal and ventral)
b. Classify as hypermotile, normomotile, hypomotile and amotile
c. Percussion to identify gas-filled organs

Question 27

in a colic case for a stallion, what should we palpate?

Answer 27

palpate scrotum

Question 28

when should we do a per rectum exam for a colic call?

Answer 28

Advised to be carried out on all cases of colic if possible
> unless danger to yourself or animal

Question 29

per-rectum examination protocol
- when to do it
- how to stay safe
- how much of the abdominal cavity content can we feel?
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- overall protocol:
> what to wear
> avoid injury of animal
> how to palpate
> what if peristalsis?
> what if straining after sedation
> feces?

Answer 29

1. Advised to be carried out on all cases of colic if possible
2. Restraint important
3. If difficult give a sedative (xylazine and butorphanol)
4. Can palpate only 40 % of abdominal cavity content
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5. How?
   a. Use protective sleeves
   b. Take off jewellery
   c. Well lubricate arm
   d. Look for signs of blood around the anus before
   e. Pull aside the short tail hairs
   f. Insert your arm as a cone
   g. Pull back feces if present
   h. Palpate with flat tips of fingers
   i. If strong peristalsis allow your hand to be pushed back to avoid rupture
   j. If straining after sedation > infusion in rectum of 30-60 ml of 2% carbocaine or lidocaine
   k. Note presence or absence of feces, whether scanty, loose or covered in mucus

Question 30

good drug for relaxing the anus for rectal exam

Answer 30

buscopan

Question 31

structures palpated per rectum

Answer 31

• bladder
• vaginal rings
• uterus
• ovaries - cysts, hematomas, CLs, tumors
• spleen and kidney
• cranial mesenteric artery
• intestine
• psoas muscle

Question 32

where do we find the bladder on rectal palpation? what does it feel like:
- in colicky animal
- in cystitis
- other things we may feel?

Answer 32

(1) Pear shaped structure lying beneath the rectal floor within the pelvis
(2) May be distended in colicky animal > too painful to assume posture
(3) Wall thickened in cystitis
(4) Calculus formation
(5) Pelvic urethra is a 1.5 - 2.0 cm diameter tube within the pelvis

Question 33

where do we feel the vaginal rings per rectum? what do they feel like? what should we ensure?

Answer 33

(1) Anterior border of the pelvis at 4 and 8 o’clock
(2) Slit like openings with a spermatic chord entering
(3) Ensure that no coils of intestine present in it

Question 34

what should we check in the uterus per rectum?

Answer 34

(1) Check for pregnancy, torsion
(2) Rupture of middle uterine artery in the broad ligament

Question 35

what should we check about the spleen and kidneys per rectym?
- what might we feel in left dorsal displacement of the large colon?

Answer 35

(1) Cranially, left side  palpate caudal edge of the spleen (thin, sharp edge) should be against the abdominal wall
(2) Spleen may be displaced medially in cases of left dorsal displacement of the large colon (LDDLC)
(3) Right of the spleen (mid abdomen) nephrosplenic ligament and posterior pole of left kidney

Question 36

where might we feel the cranial mesenteric artery per rectum? what should we feel for?

Answer 36

(1) Found running forward along the aorta to the caudal medial edge of the left kidney
(2) Palpate for enlargements of the arterial wall, or aneurysms

Question 37

• what does food impaction feel like per rectum?
• distension with gas / fluid?
• edema?
• peritonitis?
• SI distension?

Answer 37

(a) food impaction feels like firm bread dough, easily indented by digital pressure but impressions remain
(b) distended intestine with gas or fluid can be indented but impression does not remain
(c) feel thickness of bowel > edema
(d) smoothness of the peritoneum > if roughened, gritty feeling > peritonitis following bowel rupture
(e) small intestine can become distended to the same diameter as the small colon > fecal balls and the single tenial band in small colon

Question 38

when is the only time we can feel the small intestine per rectum?

Answer 38

• only identifiable if distended

Question 39

what should we check if there is blood present on our glove after a rectal exam?
- should we tell the owner?

Answer 39

a. Check if presence of rectal perforation
b. Essential that you inform the owner or the agent immediately
c. Failure to identify and acknowledge that a tear has occurred would be considered grounds for a successful prosecution