Serosal injury in the equine jejunum and ascending colon after ischemia-reperfusion or intraluminal distention and decompression.
OBJECTIVE
To document morphologic changes that occur in equine intestinal serosa after experimentally induced ischemia and subsequent reperfusion (jejunum, ascending colon) or after intraluminal distention and decompression (jejunum).


METHODS
Morphologic effects of ischemia-reperfusion or intraluminal distention-decompression determined on the serosal layer of the equine jejunum. The large colon serosa was evaluated after ischemia-reperfusion injury.


METHODS
Seven adult horses.


METHODS
After induction of general anesthesia and ventral median celiotomy, ischemia was created by arteriovenous (AVO) and lumen occlusion of a 20-cm segment of jejunum and ascending colon for 70 minutes, followed by a 60-minute reperfusion period. Intraluminal distention (25 cm H2O) was created in a second 20-cm jejunal segment and maintained within the abdomen for 120 minutes, followed by a 120-minute decompression period. Seromuscular biopsies were obtained upon entering the abdomen and after the ischemic and reperfusion periods, and after the distention and decompression periods along with corresponding control seromuscular biopsies. Samples were processed and examined by light microscopy, transmission electron, and scanning electron microscopy.


RESULTS
Ischemia and reperfusion, and intraluminal distention and decompression, resulted in severe morphologic changes in the seromuscular layer of equine jejunum. A similar period of ischemia-reperfusion caused minimal changes in the ascending colon serosa.


CONCLUSIONS
Adult equine jejunum sustains more serosal damage than the ascending colon after similar periods of ischemia-reperfusion injury. Intraluminal distention and subsequent decompression causes serosal damage in the equine jejunum.


CONCLUSIONS
The small intestine is more susceptible to seromuscular layer damage than the ascending colon.
Marion duPont Scott Equine Medical Center at Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic and State Institute, Leesburg, VA, USA.
R M
RM
Dabareiner
K E
KE
Sullins
N A
NA
White
J R
JR
Snyder
D000818:Animals; D003106:Colon / Q000293:injuries* / Q000473:pathology; D019299:Decompression, Surgical / Q000009:adverse effects / Q000662:veterinary*; D005260:Female; D006734:Horse Diseases / Q000601:surgery*; D006736:Horses; D007415:Intestinal Obstruction / Q000601:surgery / Q000662:veterinary*; D007583:Jejunum / Q000293:injuries* / Q000473:pathology; D008297:Male; D015427:Reperfusion Injury / Q000503:physiopathology / Q000662:veterinary*