Page 375 - WSAVA2018
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perpendicular to the table.
Your Singapore, the Tropical Garden City
L. Smart1
1Murdoch University, College of Veterinary Medicine, Murdoch, Australia
Acute gastric distension is a common cause of abdominal pain in emergency medicine, though it
can sometimes be difficult to appreciate on physical examination. Findings on abdominal radiographs may also, at times, be ambiguous. This talk will cover the approach to common causes of acute gastric distension; including gaseous gastric dilation (GD), gastric dilation and volvulus (GDV), food engorgement and fluid distension.
Gaseous distension
Gas dilation of the stomach typically falls into two different categories; gaseous dilation related to the syndrome of GDV and gas distension secondary to aerophagia. Aerophagia, secondary to respiratory distress, usually only causes mild distension. However, sometimes the gaseous distension can impede caudal displacement of the diaphragm and reduce tidal volume, contributing to respiratory distress. In these patients, decompressing the stomach may relieve some of the respiratory distress. Often these patients have such severe respiratory distress that sedation and intubation is imminent. If the patient is already anaesthetized, then it is prudent to decompress the stomach via orogastric intubation (OGI) if distension is evident. If the patient is conscious, then careful nasogastric intubation (NGI) can be attempted, however the procedure must be aborted if it starts to compromise the patient. Gastric trocarisation is not usually indicated in these patients as the distension is not typically severe or compromising perfusion, and it carries the risk of trauma to abdominal organs.
Gaseous gastric dilation, or dilatation, in a large breed, deep chested dog is a problem that is inevitably situated on the continuum to GDV. Typical history is similar to GDV and includes acute retching, hypersalivation, a distended abdomen and agitation. These signs often occur in the early morning or evening, related to
meal times. Physical examination findings are often similar to that of a GDV in the early stages, which
are predominantly tachycardia, abdominal pain and tympanic abdominal distension. Some dogs do not have obvious tympanic abdominal distension due to their stomach being mostly under the rib cage. Any signs
of vasoconstrictive shock (pale mucous membranes, decreased pulse amplitude, delayed capillary refill time, cool extremities) usually indicate that volvulus is present, but can still occur with severe gaseous dilation. Some dogs with early GD or GDV can present with signs of
 Place the sagittal saw or osteotome on the line marked on the cranial femur between the greater and lesser trochanters.
Ensure that the saw or osteotome blade are perfectly vertical / perpendicular to the table. By doing this you are cutting through the femoral neck in the direction of the acetabulum. The acetabulum is medial to the femoral neck and so is protecting the neurovascular structures around the hip joint from the blade.
Commence the cut and concentrate on keeping the sagittal saw blade or osteotome blade “vertical to the world” / perpendicular to the table and on the line
you marked between the medial edge of the greater trochanter and the dorsal edge of the lesser trochanter. Provided that you stay perfectly vertical and, on the line, and that your assistant keeps the leg externally rotated at 90 degrees, you will have made the cut in the correct location removing all of the femoral neck and the femoral head.
An excision arthroplasty rasp, which is designed for this task, is used to smooth the ostectomy if necessary. Typically this is unnecessary with a sagittal saw but is usually necessary with an osteotome.
Take care to completely close the joint capsule over the acetabulum as this is important in interposing thick fibrous tissue between the acetabulum and the femur. The rest of the soft tissues are closed as described in standard surgical texts.

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