EqMed, Q2, V
Card Set Information
EqMed, Q2, V
EqMed, Q2, V
what are most common sites for large colon impaction? are they palapable on rectal?
pelvic flexure, left colon (can palpate via rectal )
right dorsal colon - transverse colon junction (in front of cecum, can't palpate)
what is classic sign noted with large colon impaction?
what are clinical signs associated with large colon impaction?
mild colic; mild dehydration
minimal systemic deterioration unless prolonged w/o tx
what is peritoneal fluid like with large colon impaction?
typically normal, if left untreated can see elevated TP
what is seen on US? rectal palpation? gastric reflux?
unmistakable lesion w/rectal palpation; pelvic flexure at pelvic inlet
generally no reflux
what is treatment for large colon impaction?
isotonic *enteral fluid therapy* to hydrate + stim. gastrocolic reflex
laxatives; Mg therapy to pull fluid into lumen
what is complication associated w/returning horse to feed after relieving large colon impaction?
-return slowly, monitory water intake
what gets entrapped in nephrosplenic space?
left dorsal colon
- pelvic flexure or entire left colon
what are perfusion parameters like with nephrosplenic entrapment? colic signs?
mild-severe colic signs
what is determined via rectal palpation?
feel taenia/bands of L ventral colon coursing dorsocranially
enlarged spleen - displaced ventromedially
gas/feed in colon
what would US show with nephrosplenic entrapment? Peritoneal fluid?
US shows colon btwn kidney and spleen
fluid is normal (caution not to puncture spleen)
what are the 4 options for treating nephrosplenic entrapment?
: restrict feed + fluids, hope for spontaneous recovery
: phenylephrine (alpha agonist) - splenic contracture - jog to free
: IV GA and roll (R lateral - Dorsal recumbency - L lateral)
: surgery - GA, ventral midline
what are options to prevent reoccurrence of nephrosplenic entrapment?
laparoscopy to ablate the space
colopexy and colonic resection (more side effects)
what minerals comprise an enterolith?
magnesium ammonium phosphate crystals around a nidus
what is geographic distribution for enterolithiasis? what breed? what age? what feed?
SW, California, Florida, Indiana
alfalfa (high Mg concentration)
what are clinical findings associated w/enterolithiasis?
recurring acute bouts of pain
if obstructs transverse colon - severe pain and distended prox. colon
can you palpate enteroliths via rectal? what will peritoneal fluid be like?
not usually, if in transverse can't feel them
can see on rads
what is treatment for enterolithiasis?
surgery - pelvic flexure enterotomy
(perfectly round - single stone; polyhedral/flat - look for more)
what is signalment associated with fecaliths?
miniature horses; ponies (dental problems; dietary indiscretion)
young; <1yr and older too
no sex predilection
where is fecalith usually found? what signs are associated?
no feces being passed
mild to mod. colic
severe abdominal distention
what is recommended treatment for fecalith?
surgical removal - pelvic flexure enterotomy
(trocharize cecum prior to surgery if necessary to improve venous return/ventilation)
what leads to small colon impaction? what season is associated?
dehydrated feces (winter, decr. water intake)
inspissated fibrous fecal material
what is felt on rectal palpation with small colon impaction?
feel impaction in small colon
could be difficult to feel due to distention proximal to impaction
How are perfusion paremeters with small colon impaction?
endotoxemia common (blood from SC bypasses liver -strait back to heart/circulation)
what is a common complicating feature of small colon impaction?
T/F: Small colon impaction should be considered in any horse presenting for colic or w/history of diarrhea, and a rectal should be performed.
how is small colon impaction treated?
can try medical (fluids + laxatives)
surgery usually necessary (colon massage or enterotomy)
- also do pelvic flexure enterotomy to remove ingesta proximal so small colon can "rest"
what is the cause of thromboembolic colic?
strongylus vulgaris migrating through cranial mesenteric artery - arteritis from molting L4-5
what are clinical findings associated with thromboembolic colic?
large intestine gas distention
fremitus (when rectal - cr. mesenteric a.)
mild-mod-severe colic signs
how old are horses affected by thromboembolic colic?
>1 year due to long prepatent period of the strongyle
how is thromboembolic colic treated?
surgical resection of the infarct
Ivermectin as prevention (highly effective)
what is signalment commonly associated with large colon volvulus?
lush pastures/high CHO
what are clinical signs associated w/large colon volvulus?
severe unrelenting pain; sudden onset
non-responsive to analgesia = hallmark
abdominal compartment syndrome (severe gas distention - depressed ventilation/venous return)
+/- gastric reflux
what is treatment for large colon volvulus?
resection of devitalized sections (may not be devitalized if only rotated 270 degrees)
colopexy to prevent recurrence
laminitis prophylaxis post-op