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									     Large Animal
     Surgery

                LDA/ Abomasal Volvulus


Amy Fayette
November 2005
What is a prerequisite for getting
LDA
   Abomasal atony
What are some predisposing
factors to LDA
 Decreased rumen volume
 Displacement of abdominal viscera
What are causes of abomasal
atony that may lead to LDA
 Increased abomasal VFAs
 Hypocalcemia
 Histamine (mastitis or metritis)
 Alkalemia
 Calving
Are cows with LDA anorexia?

   Selectively eat hay but refuse grain
What is the temp for cows with
LDA
   Normal
When doing a surgical correction
for any abomasal displacement,
dilation or torsion what are the
primary objectives
 Replace the abomasum to its normal
  position
 Stabilize the abomasum in the normal
  position
What are the 4 surgical
procedures that can be done to
treat an LDA
 R paralumbar omentopexy
 L paralumbar abomasopexy or
  omentopexy
 R paramedian abomasopexy
 Closed suture technique
What physical exam finding is
pathognomonic for an LDA
   Left sided ping
If you have a cow with a left
sided ping but a fever what
should be your differentials
   LDA plus metritis or mastitis
What lab findings should be
checked in a cow with LDA
 Check for ketosis
 Check for hypocalcemia
Why would a cow with LDA
develop a secondary ketosis
   Energy deficit d/t animal not eating grain
    and still producing milk
What are some of the advantages
of correcting an LDA w a R
paralumbar ometopexy
 Cow stays standing
 One person can do it
 Less trauma to the abomasum
 Good exploration of the abdomen
 Can massage the uterus
What are some disadvantages to
correcting an LDA w a R
paralumbar omentopexy
   More skills and experience required
   Difficult to do w highly friable omentum
   Dilations are still possible and possibly twists
   Size of the surgeon may be a limiting factor
   Not in cattle that have had an IP injection
   Not easy with a 3rd trimester uterus
   Adhesion or position of the abomasum may
    limit its use
L flank incision
what are these two structures
what is the diagnosis
   LDA
    – A is the abomasum
    – R is the rumen


                              R
                          A
What are the advantages to using
a L paralumbar abomasopexy or
ometopexy to treat LDA
 Cow remains standing
 Good in advanced pregnancies
 Can be used to demonstrate to students
  or clients
 Good for visual inspection
 Ulcers can be oversewn
 Good when adhesions are present
 Can be used to massage the uterus
What are the disadvantages to
using a L paralumbar
abomasopexy or ometopexy to
treat LDA
 Assistant needed
 Size of surgeon may be a limiting factor
 Liver difficult to palpate
 Potential exists for small bowel
  entrapment
 Fistula formation possible
What are some of the advantages
to using a paramedian
abomasopexy to treat an LDA
   Strong adhesion formed
   Abomasum returns to a normal position
   Less manipulation and decompression
   Incision scar not readily visible
   Good exterioration of the abomasum
   Size of surgeon not as important
   Spontaneous uterine emptying b/c in dorsal
   Good in young calves
What are some of the
disadvantages to using a
paramedian abomasopexy to treat
an LDA
 Inability to visualize and work w
  adhesions
 Dorsal recumbency
 Danger of dehiscence
What is the main indication for
using a closed suture technique to
treat an LDA
   Cow that is a poor surgical candidate
How do you roll a cow with an
LDA
 Lie it on the right side
 Roll onto back
 Allow gas to float abomasum to ventral
  midline
 Roll to left side
 Allow cow to get up
How do you verify that the LDA
is now on the right paramedian
   Listen for ping that was on the left
    should now be on the right
What should be done after rolling
cow
   Tack abomasum into place
What are the advantages to using
a closed suture/bar suture
technique
 Quick
 Inexpensive
 Good for cows that are a poor surgical
  risk
 Simple
What are the disadvantages to
using a closed suture/bar suture
technique
 Cannot visualize abomasum
 Must be absolutely sure of diagnosis
 Fistula possible
What is your diagnosis

   Abomasal fistula
What is some common sequelae
following abomasal fistulae
 Blood loss
 Loss of HCl leading to metabolic
  alkalosis
What is the cause of abomasal
fistulae
   Using nonabsorbable suture material
    that penetrated the lumen of the
    abomasum when correcting an LDA
What is the tx for abomasal
fistulae
   Surgical correction- use stainless steel
    sutures if there is infection and
    inflammation
What are the differentials for a
right sided ping
   RDA
   Abomasal torsion
   Cecal torsion
   Gas in the spiral colon
   Pneumoperitoneum
   Intussusception
   SI blockage
   Gas in the uterus
   Pneumorectum
What is your diagnosis for the
yellow circle
   Abomasal torsion
What is your diagnosis for the
red circle
   Abomasal dilatation
How can you treat an RDA

 Ca++, dextrose, exercise
 Or surgery
Why might you want to consider
surgery vs medical tx
   RDA can progress to volvulus
Can you palpate LDA, RDA or
volvulus?
   Only volvulus
Is a right paramedian or right
flank omentopexy better for a
case of abomasal volvulus
   Right flank omentopexy since the
    animal is probably already in shock
What is the most important thing
to do when treating an abomasal
volvulus
   Decompress the abomasum
What other drugs need to be
given after correcting an
abomasal volvulus
   ATBs, banamine, hypertonic saline
As you pump out fluid from the
abomasum how do you know the
volvulus is corrected
   Pull on the omentum until you can see
    the pyrlorus
What is the death rate for
abomasal volvulus post sx
   24-62%
What is the prognosis for RDA
post sx? How about LDA?
   Both have good prognoses
The cases of abomasal volvulus
that die acutely die from___
 Circulatory collapse
 Hemodynamic and metabolic
  derangement
The cases of abomasal volvulus
that die after chronic dz die from
_____
 Abnormal abomasal transport (vagal
  indigestion)
 Damage ot abomasal vasculature,
  nerve supply and musculature
 Acidosis, hypokalemia, hypochloremia
 Endotoxemia
Post sx for abomasal volvulus you
have a cow that has a poor appetite,
no feces, is depressed and has
severe abdominal distention…what
should you use to treat this animal
  Neostigmine or
  Metoclopramide
What is the diagnosis if the cow
doesn’t respond to that tx
   Vagal indigestion
Do cows w GI obstruction get
met alkalosis or met acidosis
   Met alkalosis
What is the most important
prognostic factor in cases of
abomasal volvulus
   HR
This ewe has a normal TPR, slight
abdominal distension, is interested
in eating but doesn’t and has a firm
viscus found on deep palpation in
the right ventral quadrant of the
abdomen….what is your main
differential
   Abomasal emptying
    defect in suffolk
    sheep
What is the tx for this condition

 IV fluids w electrolytes, mineral oil PO
 Abomasotomy to remove ingesta
What other breed has a
predilection for this disease
   Dorsets
What is the prognosis for this
sheep
   Guarded to poor
If you have a case of abomasal
emptying defect what should be
your next step
   Evaluate the flocks genetics
You have a cow with a right
sided ping, a large distended
viscus in the pelvic inlet and
distended SI, off feed, agalactia,
and a HR of 78….what is your dx
   Cecal volvulus
What is the tx for cecal volvulus

   Surgical decompression
Should you pexy the cecum to
prevent recurrence
   Cecum cant function if you pexy it

								
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