Food Animal- Diseases of the Abomasum 2

drraythe's version from 2016-04-29 15:05

Why does hypochloremic metabolic alkalosis occur? + Tests and Treatment

Question Answer
what is the normal path of H+ and Cl- in the GI?Hydrochloric acid (HCl) is produced in the abomasum, and the H+ and Cl- move with the GI contents out of the abomasum and into the duodenum, where they are reabsorbed for the body to utilize
ing LDA/RDA/AV, what happens to the hydrochloric acid in the abomasum?H+ and Cl- sequestered in abomasum; not reabsorbed in small intesTIne! This leads to hypochloremia and alkalosis
what are normal Cl- levels? what are they like with LDA? AV?NORMAL: 95-110. LDA: 80-90. AV: 60-80 (and might be even lower with a chronic lesion!)
what is the normal pH of rumi urine?pretty alkalotic- usually between 7-8.5 pH
Paradoxic Aciduria--- a cow with DA might have ACIDIC URINE!! even though they have an ALKALOSIS. WHY??? (what is the pathophys)although you think they'd want to retain their H+, the drive to retain Na+ is STRONGER! This occurs because dehydration and hypotension are present. So the kidney decides to resorb Na+....and Na+ is a cation, and +s need to match the -s, and USUALLY Cl- follows Na+ BUT THE CL- IS TRAPPED IN THE ABOMASUM!! So instead of trying to keep a negative charge, the body tries to get rid of a positive in exchange for keeping other positives. So usually it would dump K+. BUT WAIT, there IS not K+ because THE COW ISN'T EATING. So, then it has to resort to dumping out H+ even though it is alkalotic, in order to retain Na+
What is a Liptak test? what does it test for?ONLY TESTS FOR LDA!! This is used to rule out rumen ping which you might confused with an LDA since they are on the same side now. What you do is aspirate fluid ventral to the gas ping. If the fluid is pH <4.5 with NO protozoa, this is LDA (you are aspirating acidic abomasum content)
what pH is definitive in a liptak test to know you have LDA?<4.5 pH
what are the sx options for LDA versus RDA/AV?LDA: Left flank abomasopexy, Right paramedian abomasopexy Right flank omentopexy, Right flank pyloropexy..... RDA/AV: Right flank omentopexy, Right flank pyloropexy, Right paramedian abomasopexy., the only diff is that with an LDA you can also so a left flank abomasopexy
what are the three non-surgical options for tx a DA, and which ones are only used for particular displacements?(1) you can roll them (works for all) (2) roll and toggle (LDA only) (3) blind stitch (LDA only)
(pic) flowchart of tx options for DA
describe how to do a Right Flank OmentopexyDeflate abomasum, Pull abomasum back to right side, Create pexy between omentum and right body wall
what are the advantages and disadvantages of a Right Flank Omentopexy?ADVANTAGES: Allows exploratory of the abdominal cavity (rumen isnt in the way), Can be performed alone. DISADVANTAGES: Requires long(ish) arms!, Omentopexy can fail over time
describe how to do a Right Flank PyloropexyNearly identical to right flank omentopexy (Deflate abomasum, Pull abomasum back to right side, Create pexy), but Involves pexy between pylorus and body wall (May be selected based on clinician preference)
what are the advantages and disadvantages of the Left Flank Abomasopexy?ADVANTAGES: Secures abomasum in normal anatomic position. DISADVANTAGES: Requires even longer arms! (than the right flank omentopexy), Requires 2+ people, Cannot evaluate the remainder of the abdomen <img src=""height="200">
which sx approach allows you to explore the abd?right flank omentopexy
which sx approach need two or more people to do?Left flank abomasopexy
what is the sx procedure you must do when the cow is recumbent?Right Paramedian Abomasopexy
advantages vs disadvantages of the Right Paramedian Abomasopexy?ADVANTAGES: Do not need long arms!, Direct visualization of pexy. DISADVANTAGES: need to sedate/cast cow, cant eval remainder of abdomen
advantages vs disadvantages of the roll and toggle non-sx procedure?ADVANTAGES: Inexpensive, Fast. DISADVANTAGES: Might inadvertently toggle rumen, Toggle suture may tear, Infection
explain procedure for rolling the cow to try to fix a DA?get her on her R side, then pull up and over, and get her back on her back (SO you put her down on the side the abomasum SHOULD be on)
Pre-operative Stabilization--> how do you want to go about your fluid therapy?Oral fluid therapy not recc, they might aspirate/you are messing with the GI dont put things in the GI. IV fluid therapy would be beneficial, bc Debilitated animals are weak and may go down during surgery, cardiac output will be improved, can help you with electrolyte corrections
what kinda preoperative IV fluid might you consider if the cow has AV?Hypertonic saline (lots of electrolytes that she is severely lacking)
If you want to decide if you wanna give antimicrobial therapy you can consider the The Three T’s of Surgery, which are...? Then also consider...TIME: How long was the procedure? TRASH: How clean was the surgical site? TRAUMA: Are tissues damaged? Consider: Also evaluate for other concurrent problems, cost, withdrawal times, route, and the ability of agent to reach the tissue
In order to perform a procedure on a standing animal, you need to Anesthetize the flank locally. what are the 4 options of how to do this?(1) Line block (2) Inverted ‘L’ block (3) Distal paravertebral block (4) Proximal paravertebral block
how much lidocaine is too much lidocaine? what is the dose she likes?try to stay at less than 5-7mg/kg for lido (10 mg/kg is toxic)
which block is this? inverted L (make that inverted L shape, it will block everything in that area) (angle of L points towards the head)
what are the advantages and disadvantages of the line block?(just inject a line of lidocaine along where you are making your incision) ADVANTAGES: Easy to perform, Precise and accurate, Does not require much lidocaine. DISADVANTAGES: Lidocaine causes vasodilation- and you will be cutting right where it vasodilated so you will have to deal with Bleeding and Tissue edema. Also, there is No anesthesia if you extend your incision
advantages and disadvantages of the inverted L blockADVANTAGES: Easy to perform, Effective. DISADVANTAGES: Requires a lot of lidocaine, Takes a while to perform
*where do you do a distal paravertebral block, and how?you have to go DORSAL (a) and VENTRAL (b) to the transverse processes of the lumbar vertebrae L1, L2, L4**
which paravertebral block is at L1, L2, L4?distal paravertebral block
advantages and disadvantages of the distal paravertebral block?ADVANTAGES: Remote from surgical field, Fairly easy. DISADVANTAGES: Anesthesia may be incomplete, Requires a lot of lidocaine
which block is this? Distal paravertebral block
*where do you do the Proximal Paravertebral Block, and how?Administer small volume of lidocaine at spinal nerve rootlets, at T13, L1, and L2
which paravertebral block is at T13, L1, L2?proximal paravertebral block
advantages vs disadvantages of the prox paravert blockADVANTAGES: Very precise; if accurate then 100% effective, Small amount of lidocaine. DISADVANTAGES: If not accurate then not very effective. Requires spinal needle. Technically difficult
which paravert block requires more lidocaine?distal (injecting in 2 sites)
only do ABOMASOPEXY on which flank side?on the LEFT flank side. (also R of a paramedian is the other abomasopexy)
which flank side do you do the omentopexy on?right
which flank side do you do the pyloropexy on?right
what are intra-op complications you must keep in mind when sx repairing the DA?it is a Fairly safe procedure, but If it is difficult to replace abomasum be careful--> Occasionally abomasal ulcer can adhere to the leU body wall. and Pulling too hard will rip the abomasal wall!
explain the layers of the three layer closure, and what suture/patterns you will be using(1) Omentum, transversus abdominis, internal abdominal oblique (2) External abdominal oblique (3) skin........ for internal layers, do simple continuous absorbable suture. use nonabsorbable on the skin
what is some post-op supportive care you can provide?NSAIDs, B vitamins, rumen transfaunation, Intravenous/oral fluids
what is the prog for LDA/RDA?good
what is the prog for AV?Early recognition & surgical correction critical-- < 50% after 24 hrs, < 5% after 48hrs.... the prog also varies directly with Cl, and inversely with HR and anion gap
post op complications (4)(1) Decreased milk producTIon (Peak milk producTIon may never reach potenTIal) (2) Incisional abscessation (3) Vagal indigestion after AV (Atony and failure of abomasal emptying, Direct injury to vagus OR Vascular thrombosis along lesser curvature (4) Abomasal impaction
a low incidence of DA is acceptable. if you see a "herd outbreak" what should you look atAssess transition rations
how can you help prevent DA?Reduce incidence of ketosis and milk fever, Monitor postpartum cows closely, and DIET! Fiber for chewing cud, Transition new rations slowly

Abomasal ulceration

Question Answer
which cattle are most likely to get AU, is there an age?Occur in all ages of ruminants, but is most common in Intensively managed animals like calves and fresh cows
3 big risk factors for AU?Associated with stress, high concentrate diets, and NSAID use
what dz in older animals might contribute to AU?lymphoma
how common is AU in young rumis and camelids?Camelids and young ruminants at a high risk
the two classifications of AUBleeding vs perforating
general CS of AU (could apply to bleeding or perforating) (3)Bruxism, dec appetite, Decreased milk production
clinical signs of Bleeding, Non-perforating ulcersChronic, focal abdominal pain, with bleeding into the GI tract resulting in: Melena and profound anemia (Pale mucous membranes, tachycardia, weakness)
bleeding ulcers are common to happen after...calving
what might be the first sign of a bleeding ulcer?drop in milk production
clinical signs of perforating ulcers?Focal or generalized peritonitis, Anorexia, Fever, Rumen stasis
LOCALIZED peritonitis as a result of a perforating ulcer usually happens when the leak is _________. Explain what happens when you have localized peritonitisUsually occurs if leakage is SLOW. An Abscess forms and is walled-off, and Adhesions to other viscera and/or the body wall occur. they are relatively common
clinical signs of a LOCALIZED peritonitis?(remember: from a slow leaking perforated ulcer) can be variable, can be subclinical, Presentation may be similar to TRP
<img src=""height="200"> whats this?diffuse peritonitis
diffuse peritonitis occurs when there is a _________ leak. what are the clinical signs of this?happens with Rapid or massive abomasal leakage. The infection cannot be "walled off" in an abscess or sthing (like in the slow leak) so SepKc shock ensues, quickly followed by death
although uncommon, a fast/large leak leading to diffuse peritonitis often occurs when?rumis on long term NSAID use (think prostaglandins and blood flow)
Bleeding ulcers rarely _________(1)_ and preforating ulcers rarely _(2)_________(1) perforate. (2) bleed
can you use gastroscopy to dx abo. ulcer?nope lol
along with hx and PE findings, how do you dx a bleeding ulcer?Fecal occult blood (not very specific), (Regenerative) anemia
along with hx and PE findings, how do you dx a perforating ulcer?Abdominal ultrasound, Abdominocentesis
can you definitively dx an abo ulcer?(well you can't gastroscopy, so) it is very difficult! Diagnosis is usually presumptive, so Make a diagnosis of abomasal ulcers with scrutiny! and Don’t assume ulcers are the only problem!
what is the gold standard for tx of abo ulcers?proton pump inhibitors!
proton pump inhibitors are the GS tx for abo ulcers. what are the routes of admin?(1) Injectable (IV, SQ) routes are effective (Pantoprazole (Protonix®) <--expensive!) (2) Oral medications (Gastrogard®) are ineffective
Proton pump inhibitors--> cost is an issue. explain cost vs dose durationRecommended dose of pantoprazole is 1 mg/kg IV once daily ($150/day to treat a 400-kg ruminant!) it will dec HCl secretion into the abdomen, 48-72h~ of treatment required until pH changes
what is Pantoprazole?proton pump inhibitor to tx abo ulcers
aside from proton pump inhibitors, what are some other tx you could give for AU? (4)(1) Decrease stress (2) Gastroprotectants---> Bismuth subsalicylate (1 gallon for 600-kg cow) might help (3) Blood transfusion if anemia severe (bleeding ulcer) (4) Avoid corticosteroid and NSAID use!
how should you manage the diet of a cow with a AU?HAY ONLY, NO GRAIN
what is the prog of a bleeding ulcer? perforating?bleeding- good. perforated-bad