What % of horses develop colic annually?
10%
What % of horses that develop colic require surgery?
10%
Colic risk factors
- recent change in diet
- recent change in stabling
- recent change in activity level
- previous colic or abdominal surgery
- inadequate deworming or dental care, weather?
What are the most critical parts of a history for a horse with colic?
- treatments already given
- any known medication reactions
- duration of colic
- severity of colic
How much nasogastric reflux may be considered normal?
up to 2L
How long is “skin tent” in a normal horse?
2-3 seconds
What are some gut sounds that may be heard?
- opening of ileocecal orifice (sounds like drain emptying)
- sand in ventral colon
- short, sharp tinkling sounds
What factors are used in assessing dehydration status?
- skin tent
- degree of enophthalmos
What are normal parameters for abdominal fluid?
TNCC<10,000 cells/ul
TP<2.5g/dl
When should you consider referral?
- refractory/unrelenting pain
- lack of response to therapy (think about referral on second visit to patient
- evidence of endotoxemia (consistently elevated HR, congested gums, prolonged CRT)
- findings inconsistent with a simple colic (excessive reflux, distended viscous tight band, extensive impaction on rectal, serosanguinous abdominocentesis)
Causes of nasogastric reflux
- pyloric obstruction
- SI obstruction or strangulation
- nephrosplenic entrapment
- occasionally large colon volvulus
- anterior enteritis
Causes of tight bands
- large colon displacement or volvulus
- grossly distended cecum
- mesentery under tension
- uterine torsion
Causes of abnormal abdominal taps
- small intestinal compromise
- enteritis
- large intestinal compromise
- splenic tap
Normal pulse in a horse?
48 bpm or less
What two equine analgesia drugs are often combined due to synergism?
xylazine, butorphanol
Typical clinical signs of large intestinal simple obstruction
- consistent mild pain
- normal gums usually
- elevated pulse
- distended or impacted colon
- normal abdominal tap
Where are enteroliths usually located?
- right dorsal colon
- transverse colon
- small colon
Surgical approach to enteroliths
pelvic flexure enterotomy +/- incision in the right dorsal colon or where enterolith is located
Risk factors for enteroliths
- high calcium diet
- ingestion of foreign body
What are the causes of secondary cecal impaction?
- associated with ortho or ophtho pain
Treatment for secondary cecal impactions
cecal evacuation & aggressive pain management
Treatment options for NS entrapment
- phenylephrine, walk/trot
- roll horse +/- phenylephrine
- straight to surgery for horses not suspected to respond to phenylephrine or don’t want to give phenylephrine
What are causes of simple obstruction of small colon?
- meconium impaction in foals
- fecal impaction in miniature horses
Typical clinical signs with small intestinal strangulating obstruction
- consistent moderate pain
- congested gums
- elevated pulse
- reflux
- multiple distended SI loops
- serosanguinous tap
