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(a) Cecum and large colon with intended line of transection L,L' shown. (b) Enlarged views of cauterization of anastomotic branches between the right colic artery and the colic branch of the ileo-ceco-colic artery.
Source publication
The effect of resection of 75% (length measurement) of the large colon in ponies was studied. Ten ponies in good physical condition were divided into two groups: group I consisted of the six experimental ponies and group II of four control ponies. Preoperatively and postoperatively for five months, ten clinicopathological parameters were determined...
Contexts in source publication
Context 1
... of transection identified (in ponies of group I) with 2-0 synthetic absorbably suture material (polyglac- tin 910, Ethicon Sutures Ltd., Peter- borough, Ontario, Canada). The colic branch of the ileo-ceco-colic artery and the right colic artery and veins at that location were ligated and the mul- tiple anastomotic branches ligated or cauterized (Fig. 1). The intended line of transection was then clamped with a Furness intestinal clamp and the bowel transected distal to the clamp with a surgical ...
Citations
... However, there are reports of survival after resection of parts of the large colon (16)(17)(18)(19)(20). Recently it has been shown that partial resection ofthe large colon is compatible with life and produces no apparent serious side effects in experimental horses and ponies (21)(22)(23)(24). ...
... After aseptic preparation, a ventral midline celiotomy was performed while anesthesia was maintained with halothane and oxygen. The abdomen was explored, the problem identified (Table I), and a large colon resection performed as previously described using a side-toside anastomosis (21,22). Polyglactin 910 (Vicryl: Ethicon Sutures, Ltd., Peterborough, Ontario) was used for all closures of the intestine and abdominal wall. ...
... In the postoperative period of the surviving horses there were no signs of abdominal pain, which concurred with the findings in experimental ponies in past studies (21)(22)(23)(24). In experimental work (20), some of the ponies had shown occasional diarrhea in the first postoperative week. ...
Extensive resection (50-75%) of the large colon was performed in 12 horses. Indications for resection were: loss of viability due to large colon volvulus (seven), thromboembolic episode (three), impairment of flow of ingesta due to adhesions (one), or congenital abnormalities (one). The time required to correct the primary cause of abdominal pain and complete the resection ranged from 2.5 to 4.75 hours. Three horses had severe musculoskeletal problems postoperatively and were euthanized in the recovery stall. Four other horses were euthanized early in the postoperative period because of: further large colon infarction (two), ileus (one), or small intestinal problems (one). Five horses survived with no apparent nutritional or metabolic problems during two to three weeks of hospitalization. Clinical data were obtained from these horses from nine months to eighteen months postoperatively and revealed no clinical or clinicopathological abnormalities in four of them; the fifth horse exhibited diarrhea and weight loss four months postoperatively but responded to diet change.
This chapter includes descriptions of pelvic flexure enterotomy, large colon evacuation, and large colon resection in the horse, with discussion of indications and complications.
Colic is one of the most common and challenging problems that equine practitioners encounter. Although the majority of horses with colic can be treated with medical management, up to 10% of horses with colic require surgical intervention. The decision for surgery is often straightforward based on historical and diagnostic information. However, some horses require further diagnostics and observation to determine if surgery is needed. Surgical intervention can be life saving. However, complications may arise during surgery, in the immediate postoperative period, or during long-term management, and often require further surgical intervention or medical management. This article addresses some of the most common surgical complications of abdominal surgery for colic to help prevent, recognize, and treat these complications.
With large colon resection and anastomosis, up to 95 per cent of the length of the large colon has been successfully removed. A hand-sewn end-to-end anastomosis is effective for lesions in the left dorsal colon and pelvic flexure. Transection and a side-to-side anastomosis with stapling equipment is most effective for extensive resections (greater than 50 per cent). Horses with extensive colon resection (95 per cent) have permanent deficiencies of water absorption and digestion of cellulose and protein. Fermentative capacity is reduced, owing to decreased particulate matter retention time in the smaller capacity colon. These deficits are minimized with alfalfa hay as the source of forage (fed at 2 per cent of the body weight), and normal blood variables and body weight can be maintained. Voluntary intake increases to help maintain a positive nutrient balance. Grass hay, owing to the higher cell wall content, is inadequate as the sole source of energy and protein, and weight loss will occur. Ad libitum intake of water is recommended at all times, owing to the increased fecal water loss.
Optimal intestinal healing occurs when like layers of the intestinal wall are aligned. Hand-sewn, double-layer, end-to-end anastomosis that apposes the mucosa and produces slight inversion of the seromuscular layer is recommended to minimize adhesion formation and provide reasonable alignment of the intestinal layers. Stapled, everted, triangulated, end-to-end anastomosis is not recommended because of extensive adhesion formation and poor healing of the intestinal layers. The preferred stapled techniques create an inverting, side-to-side stoma between the bowel segments.
The nutritional implications and adaptive processes resulting from resection of 75% of the length of the large colon in ponies were investigated. Ten ponies in good physical condition were divided into two groups: six in the experimental group and four in the control group. During the sixth postoperative month, two digestibility studies were conducted, and phosphate fractional renal excretion and serum biochemical profiles were determined in both groups. The ponies (N = 10) were euthanized six months postoperatively, and gross and histopathological examinations were performed. Results of the serum biochemical profiles, phosphate fractional renal extraction and digestibility studies showed no statistically significant difference between groups except for the serum phosphate concentration. However, large colon resection was associated with hypophosphatemia in three of the six ponies and produced an overall significantly lower phosphate concentration in the experimental ponies. This hypophosphatemia suggests that some dietary modifications may be needed postoperatively in ponies or horses undergoing this surgical procedure. Postmortem examination and histopathological examination failed to demonstrate differences between groups. Adaptive mechanisms, specifically mucosal hypertrophy or hyperplasia, were not observed.
Recent advances in abdominal surgical techniques in the horse have resulted in improved survival rates and reduced postoperative morbidity. The development of abdominal surgical procedures in horses has paralleled the development of safe anesthetic protocols and innovative technological advancements in humans. Irrespective of the species, the application of sound surgical principles is still the foundation of surgical intervention. This article describes recent advances in equine gastrointestinal surgical techniques. The availability and application of innovative intestinal surgical devices and their specific uses in equine gastrointestinal surgery are also described.
