Abomasal Displacements

Question 1

What is the pathogenesis of abomasal displacement?

Answer 1

Abomasal atony –> abomasum fills with gas –> lifts to left or right
Most commonly the left

Question 2

What are some risk factors for abomasal displacements?

Answer 2

Dairy cow in early lactation 
Housed
SARA
Ketosis and FMS
Hypocalcaemia 
Concurrent inflammatory process - metritis / endometritis 
Poor cow comfort and lameness 
Anything that reduces DMI

Question 3

What is the most common abomasal disorder?

Answer 3

Left displaced abomasum

Question 4

What are the clinical signs of a left displaced abomasum?

Answer 4

Reduced milk yield
Ketosis
Prefers one fibre to concentrates
0-4 weeks post calving

Question 5

How can you diagnose a displaced abomasum?

Answer 5

Resonant Ping sound of the abomasum which is in an abnormal place
Spontaneous tinkling and gurgling
Absence of rumen sounds over the abomasum

Question 6

What are some treatment options for a left displaced abomasum?

Answer 6

1. Cast and roll cow - least successful method
2. Feed good quality roughage
3. Toggle
4. Abomasopexy

Question 7

What are the toggle positions?

Answer 7

Caudal toggle - 6 inches caudal to the xyphoid,
2 inches to the left

Cranial toggle - 4 inches cranial to the caudal

Question 8

Name the surgical methods of treating a left displaced abomasum?

Answer 8

1. Left and right sided approach - requires 2 vets
2. Utrecht - more anatomically correct
3. Right sided
4. Right paramedian approach
5. Ventral abdominal paramedian

Question 9

What should you do if the cow simultaneously has an LDA and endometritis?

Answer 9

Delay surgery until the septic focus has been treated

Not an emergency

Question 10

What post-operative care should you give after abomasal surgery?

Answer 10

Pen/strep
NSAIDs
Treat ketosis - propylene glycol, glucose, steroids
High fibre diet

Question 11

Why is a right sided abomasal displacement more worrying?

Answer 11

Torsion can occur

Animal becomes severely dehydrated, hypochloraemic and has metabolic acidosis due to dilatation

Question 12

What are the 3 phases of an RDA?

Answer 12

1. Atony and Dilatation
2. Displacement
3. Torsion - more space on the right so more likely to torse

Question 13

What are the metabolic sequelae of an RDA?

Answer 13

H+ and Cl- pools in the abomasum
- hypochloraemia, metabolic alkalosis, very dehydrated

Endotoxaemia due to ischaemic mucosal damage

Question 14

What are the clinical signs during the dilatation and displacement phase of an RDA?

Answer 14

Reduced faeces 
Dehydration
Tachycardia
Pale mm and dry
Doughy rumen 
Ping in the middle to upper 1/3 of the right abdomen
Tense viscous rectally

Much sicker and severely dehydrated if there is a torsion present

Question 15

What is the recommended treatment for an RDA?

Answer 15

Surgery to drain and replace the abomasum

Poor prognosis if very sick - consider euthanasia

Question 16

How should you provide post-operative care to a cow with an RDA?

Answer 16

Fluids - 50-100L hartmanns 
NSAIDs 
Pen/strep
Oral KCl
Calcium 40% 
Propylene glycol

Question 17

Describe how to perform a left sided omentopexy (utrect method)

Answer 17

Cow in crush
Sedate
Clip left side of the abdomen
Paravertebral nerve block
Surgically prepare the abdomen
Scrub up yourself
Left sided incision 5cm caudal to the last rib
Incise through ext, int and transverse abdominal oblique
Grasp the greater curvature of the abomasum or omentum
Stay suture through the abomasum or omentum - leave 2 long ends
Decompress the abomasum
Attach a needle to the cranial thread
Move the needle and thread down the body wall to the ventral midline site
- 4 inches caudal to the xyphoid, slightly right
Suture into the body wall
Repeat with the caudal suture 4 inches caudal
Replace the abomasum
Pull the sutures tight and ensure that no guts get trapped

Equipment: Buhner needle, nylon suture

Question 18

Describe how to perform a left or right bilateral flank omentopexy.

Answer 18

Bilateral Paravertebral blocks
Two incisions left and right, vertical, 5cm, caudal to ribs
Move hands down body wall and shake hands
Decompress the abomasum
Push to midline
Bring up to right hand incision and perform an omentopexy to anchor the abomasum