SURGERY
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Principles of Gastric
Surgery in the Dog
Dr Ross Elliot BVSc MMedVet ( Surg ) Bryanston Veterinry Hospital . Tel 011 706 6023
The stomach is generally very forgiving , however if taken lightly gastric surgery can have fatal consequences . The position of the stomach in the cranial abdomen makes exteriorisation difficult .
Anatomy The stomach is divided into four areas , which are important to identify when performing gastro-intestinal surgery . The cardia is the region where the oesophagus blends into the stomach . The fundus is the large out-pouching of the stomach along the greater curvature . The body of the stomach lies between the fundus and the pylorus and forms the reservoir of the stomach . The pylorus is the distal third of the stomach or the outflow tract . The pylorus is divided into two parts the thin walled antrum of the pylorus and the thick muscular pyloric sphincter .
The greater omentum is attached at the greater curvature and the lesser omentum at the lesser curvature . The greater omentum forms the large leaf of omentum in the abdomen . The lesser omentum forms a part of the hepatogastric ligament .
Healing of the Stomach Full thickness incisional healing of the stomach occurs rapidly . The stomach has an extensive blood supply making the regular phases of healing rapid . Collagen for repair is not only produced by fibroblasts but the smooth muscle cells of the stomach also contribute to collagen formation . The return of normal gastric strength after incisional trauma is about 14 days .
Surgical Preparation Generally surgery of the stomach is an emergency and surgical preparation involves patient stabilisation rather than a nil per os period etc . These patients should have fluid and acid base and electrolytes abnormalities corrected prior to surgery .
In elective procedures food should ideally be withheld for 8 hours to allow for gastric emptying . Fasting for longer than 12 hours can actually have negative effects . Increased fasting duration leads to increased gastric acid decreased pH , which can lead to increased gastro-oesophageal reflux .
General Surgical Principles Remember Halsted ’ s principles of surgical technique minimise tissue trauma , practise precise haemostasis , preserve the blood supply , use aseptic technique , minimise tension on the tissue , use accurate tissue apposition and obliterate dead space . The stomach is generally very forgiving , however if taken lightly gastric surgery can have fatal consequences . The greatest risk is leakage of gastric content , which can lead to significant morbidity and mortality .
The position of the stomach in the cranial abdomen makes exteriorisation difficult . The supporting ligaments such as the hepato-gastric and hepato-duodenal ligaments can be carefully transected , however it is essential to identify the important structures such as the common bile duct that run in these structures to prevent damage .
The stomach is approached by a ventral midline celiotomy for most procedures . A midline incision of sufficient length is made to allow proper visualisation ( no keyhole surgery !). Trying to save time by making a small incision will increase the risk of contamination and postoperative morbidity .
When handling the stomach it is ideal to minimise the use of instruments . Stay sutures are ideal in handling , stabilising and exteriorising the stomach and preventing abdominal contamination . Once the stay sutures have been placed , the proposed area for surgery should be packed off from the rest of the abdomen with moistened abdominal swabs . Put the moistened abdominal swabs down first to contact the serosa and then dry ones on top and adjacent to the bowel to be opened as needed to absorb contamination . Keep tissues moist to protect them and make handling less traumatic .
vet360
Issue 04 | AUGUST 2015 | 30