Abomasal Displacement & Volvulus Sx Flashcards
what is the most common abomasal displacement?
LDA
“LDA is a management disease” what does this mean?
that well managed cows should not be getting this
when do cows tend to get LDAs?
after calving: due to the incidence of many other diseases during this time, some cows are vaccinated at this time, hows come back into estrus and dont eat, etc. many contributing factors
there are like a million risk factors for LDAs. Queen all you have to do is name a few. it’s okay.
being a holstein cow with a large abdominal cavity, being older (multiparous), change in diet, decreased exercise, high concentrate feeds, hypocalcemia, ketosis, retained placenta, metritis, mastitis, endotoxemia
4 steps of general pathogenesis for displaced abomasum
small rumen (not eating), abomasal atony, gas production, displaced abomasum
what metabolic derangement does an LDA/RDA cause?
metabolic alkalosis (all acid sequestered in abomasum)
with an RTA, describe how the abomasum turns out of place
twists counter clockwise when viewed from behind and an additional counter clockwise twist when viewed from above
why is an RTA so much worse than a LDA/RDA?
RTAs result in a complete pyloric outflow obstruction and vascular compromise, potential tissue devitalization (weaken or debilitate)
true or false: a cow with signs of colic is okay to wait until morning, and usually recovers on their own with medical management
FALSE!!!!! cows with signs of colic can NOT wait until morning and usually require surgical intervention!!!
when you are doing a distant exam on a cow you suspect has an LDA or RDA/RTA, what sorts of things are you looking for (esp in differentiating between a displacement and a torsion). There are a lot of these queen so it’s okay if you dont list them all
- are they dull/depressed/shocky–>torsions will be more shocky
- how dehydrated are they? more severe with a torsion
- are they eating? more likely to not eat with a torsion
- is the cow chewing cud? less likely to with a torsion
- are there signs of colic?
- what is the abdominal contour? L or R side look enlarged?
- resp rate–>would be higher with a torsion
- check the records like if they have a rumen activity sensor or check milk production
after your distant exam on the cow, you want to do your actual PE. If you suspect an LDA/RDA/RTA, what sorts of things are you looking for?
- a high HR, the higher it is the more likely it is a torsion
- rumenation/rumen rate: probably still present with just a displacement, but may be harder to hear with an LDA since rumen is behind the gas distended abomasum. with RTAs there will be no rumination
- CBC/chem would see met alk hypochloremia and hypokalemia
C/S of an LDA
decreased appetite, decreased rumen motility, decreased milk production, ketosis, rumen contractions hard to hear
a boring person named Boring Person brings you his cow named Boring Cow. Boring Cow is eating less feed, not producing as much milk, and when you try to listen to rumen contractions they are very hard to hear. Top differential?
LDA
Boring Person has another cow named Sleepy Cow, who is not eating, is not producing feces, has sunken eyes, has a HR of 100, has weak pulses, has no signs of any ruminal contractions, and has bilateral abdominal distention. When you listen you can hear a ping on the R side. Top differential?
RTA (or RDA)
general bloodwork findings you’ll see with an LDA
met alk: high pH, high bicarb, low Cl and K, hypoglycemia, ketonemia, +/- stress leukogram
general bloodwork findings you’ll see with RDA/RTA
hypovolemia, dehydration, hemoconcentration, hyperglycemia, met alk, hypocalcemia, hypochloremia, hypokalemia, hyponatremia, paradoxic aciduria
what abnormalities will you find on your PE with an LDA/RDA/RTA?
the PING on percussion
in the case of a torsion, might have a positive succusion
can you feel a DA on rectal palpation?
only if its really big but usually not
how do you differentiate between an RDA and a RTA?
signs of shock=more likely to be a torsion
why do we do a rectal exam last?
dont want to introduce a pneumorectum–>can result in a false PING
what else besides pneumorectum can cause a false ping?
a gas filled rumen–>can feel this on rectal palpation
what are some differentials for an LDA/RDA/RTA?
ruminal tympany/bloat, pneumoperitoneum, cecal distention, gas in spiral colon, pneumoperitoneum, metritis where there’s gas in the uterus from gas proeucing bacteria
in addition to PE findings, what are some diagnostics you can do to confirm an LDA/RDA/RTA?
- BHBA test–>we know that any paripartueitn disease can be associated with DAs so if the cow has high ketones, more likely to also have a DA
- stall side calcium tests (iSTAT, Horbia)
- blood lactate: good prognosticator for acute abdomen in any animal
when making your incision for the right sided approach surgery, where are your landmarks?
one hand down from transverse processes and a few inches caudal to 13th rib
what layers are you cutting through in order when making your incision in the R paralumbar fossa? for each of these layers, what is the ideal surgical way to get through them?
skin, external abdominal oblique, internal abdominal oblique, transversus abdominus, peritoneum
skin & external ab ob: sharp dissection
int ab ob & transversus: blunt dissection OR CAREFUL sharp
transversus & peritoneum: blunt dissection
briefly describe how you do the R sided approach to fix an LDA
- start with a quick exploratory, look for ahesions and palpate the liver and the omasum
-then move around to the caudal abdomen with your left hand and pass around the caudal dorsal rumen until you can feel the body wall, then move forward until you can feel the rumen - once you can feel the rumen, you need to deflate the air either passively or actively with suction
- then you can gently push the abomasum under the rumen back to the right side
- can also pull the omentum up at a 45 degree angle until you pull the rumen under the abomasum
- reduction is completed when you can see the pyloric antrum at the incision site
- perform a pexy and close
pros and cons of a right sided flank approach
- can be done standing, can be done without assistance, can do an abdominal explore first, can fix LDA, RDA, and RTAs
- can be difficult during late pregnancy
- adhesions are harder to visualize and navigate
how to tell between an RDA and RTA when going in for surgery
after making your incision, identify the gas filled abomasum just cranial to the incision and move your hand down the medial side of the abomasum–>if you can run your hand down the medial aspect of the abomasum until you reach the body wall, it is just displaced
briefly describe how you do the R sided approach to fix an RDA
after feeling the abomasum along the medial aspect, the abomasum now needs to be drained/deflated using a large bore attachhed to a sterile tube or pump
-after it’s been pumped, the left hand pushes the top of the abomasum down to correct the CCW twist, then you can pull the omentum at a 45 degree angle until you can see the pyloric antrum at the incision site, pexy and close
briefly describe how you do the R sided approach to fix an RTA
after trying to run your hand down the medial aspect of the abomasum and being unseccessful, you still need to deflate it with a large bore and a sterile tube or pump
- after it’s been drained, you correct the CCW twist as seen from above by turning in CW direction, then correct the CCW twist as seen from behind
- pull omentum at 45 degree angle until can see pyloric antrum at incision site
- pexy and close
what is an omental pexy and why would you chose it over an abmasal pexy?
2 horizontal mattress sutures in the greater ometum and then anchored to the transversus abdominum, then the omentum is incorporated in the closure of the T abdominus
- can’t cause a pyloric outlofw obstruction this way, but these sutures can very easily rip out and tear
how does one do a pyloro/antro pexy?
horizontal matress sutures in the pyloric antrum, a bit proximal to the pylorus, dont do full thickness bites, can incorporate omentum into closure of T abdominus
better for fat cattle where fat is friable
describe what a toggle suture is and when you use it
an LDA procedure only, can cause volvulus in a cow with RDA
rolling the cow will make the abomasum float to the ventral abdomen–> cast her to the R ride and rol her CW as viewed from the rear–> few inches behind xiphoid and a few inches to the right is prepped–>identify where abomasum by percussing, then trocar is placed over the ping caudal to xiphoid and medial to midline. please see slides for more info I can’t write
pros and cons of doing toggle procedure
pros: cheaper, quicker, less prep, if successful it is faster recover and less peritonitis and less muscle trauma
cons: blind technique, sutures can rip out and cause severe peritonitis, if there are adhesions you wont be successful
what happens if you just roll the cow and don’t actually toggle the abomasum?
rolling along results in 70% reoccurance so usually not done
if the cows HR is 100bpm or higher what does this tell you?
this is a bad prognostic indicator–>56% salvaged, euthanized, or died
