Morphologic Effects of Experimental Distention of Equine Small Intestine

Abstract

The morphologic effects of induced intraluminal hydrostatic pressures (IHPs) of 0, 9, and 18 cm H2O were evaluated in 33 isolated equine jejunal segments. Fifteen segments were distended with Tyrode's solution for 1 hour and nine segments for 4 hours. Tyrode's solution was added as needed to maintain the prescribed pressures. Nine other segments were left undisturbed for 4 hours after the initial distention period. On decompression of the intestinal segments, progressive peristaltic contractions resumed in all segments. Evaluation of intestinal sections by light microscopy and transmission electron microscopy showed edema of the villi and submucosa and separation of the epithelial cells adjacent to the basement membrane in all segments. The epithelial cell necrosis found in ischemic intestine was not seen. This study indicates that the necrosis found at the villous tips in distended sections of small intestine remote from the site of obstruction cannot be reproduced by IHP increases of 4 hours duration.

Indications, complications, and outcome of horses undergoing repeated celiotomy within 14 days after the first colic surgery: 95 cases (2005–2013)

“…Arguments for early intervention with a second celiotomy include reduction of ongoing daily costs for supportive therapy and avoiding the deleterious effects of continued small intestinal distension. [14][15][16][17][18] However, because there is a chance of spontaneous resolution of postoperative ileus and considering cost and morbidities associated with a second celiotomy, surgical intervention might be delayed for 48 to 72 hours, depending on surgeons' preference. In a study 19 investigating postoperative ileus after small intestinal surgery, mean duration of postoperative ileus was 64 ± 58 hours (median, 40 hours; range, 1 to 240 hours).…”

Serosal Injury in the Equine Jejunum and Ascending Colon After Ischemia‐Reperfusion or Intraluminal Distention and Decompression

“…The importance of this mesothelial cell loss is unknown, because mesothelial cell loss, probably caused by mechanical shedding, can occur from bowel manipulation during surgery. Mesothelial cell loss without adhesion formation has been reported in equine small intestine 7 …”

“…Although many intestinal studies report the morphologic mucosal damage associated with ischemia‐reperfusion injury, 4–6 few describe the acquired serosal layer lesions. Experimentally induced intestinal ischemia and intraluminal distention caused significant serosal damage that led to adhesion formation in foals 7 . Experimentally, in adult horses, little morphologic mucosal damage was observed in jejunum distended to 18 cm H 2 O for 4 hours 8 .…”

Lidocain reduziert die Bildung eines Gewebeödemes in der ischämisch- reperfusionsgeschädigten Darmwand des Pferdes

“…Furthermore, he stated that intestinal distention and tissue pressure exceeded venous pressure quickly and increased capillary hydrostatic pressure thereby enhancing capillary filtration. As a consequence fluid accumulated in the lamina propria, resulting in oedema of intestinal wall as assessed by histological studies (Allen et al 1988). The fluid accumulation in the submucosa and muscularis in the intestinal wall of horses may also be explained by enhanced capillary filtration due to the larger extent of blood vessel filling and higher capillary hydrostatic pressure.…”