Lecture 23 3/28/25 Flashcards
What allows for the abomasum to move more freely within the abdominal cavity?
it is loosely attached to omentum, but not well adhered to the body wall
What are some facts regarding abomasum anatomy?
-volume fo 28 to 30 L
-true stomach
-produces HCl, pepsin, and renin
-undergoes 20 emptyings a day
-loosely attached in the abdomen
What is the incidence of displaced abomasum?
-relatively common
-all cattle are at risk
-slightly more common in dairy cattle compared to beef cattle
What are the financial losses associated with displaced abomasum?
-treatment
-lost of production
-culling and replacing
What are the predisposing factors for displaced abomasum?
-being a dairy cow
-being in the first four weeks of lactation
-genetics/breed predisposition
-nutrition
Which periparturient diseases are associated with displaced abomasum?
-retained placenta
-mastitis
-hypocalcemia
-metritis
How can nutrition predispose to displaced abomasum?
-low crude fiber intake
-negative energy balance
-low postpartum serum calcium levels
Why is DA often seeing following birth?
-calf takes up lots of space in abdominal cavity and rumen compresses
-after birth, there is a lot of space for the abomasum to move within
What are the first signs of DA?
-drop in milk production
-abnormal food consumption/selectively getting off concentrations
What is the clinical presentation of DA?
-anorexia
-mild dehydration
-elevated HR
-cold extremities
How is DA diagnosed?
-percussion/auscultation of abdomen (pinging)
-transrectal palpation to evaluate uterus and rumen size
What is the most common mistake when trying to diagnose DA?
pinging too caudally and missing an abomasal ping
Where should pinging be attempted in order to diagnose DA?
between the 9th and 11th/12th intercostal spaces, along a line from the ileum to elbow
How does an RDA differ from an abomasal volvulus?
RDA:
-pylorus stays caudal compared to body of abomasum
AV:
-abomasum rotates and pylorus goes cranial compared to body of abomasum
How is a ruminal ping distinguished from an abomasal ping?
rumen pings sound more dull compared to abomasal pings
What must be assessed on physical exam in a DA cow?
-heart rate
-pain level
-dehydration status
-concurrent dz
–mastitis
–metritis
–ketosis
–hypocalcemia
–abomasal ulcers
How does the type of DA impact heart rate and pain?
LDA: minor pain, HR around 70
RDA: more painful, HR > 82
AV: acute abdomen, HR > 100
What diagnostic findings on blood work are suggestive of DA?
-hypochloremia
-hypokalemia
-hypocalcemia
-metabolic alkalosis
How can oro-ruminal intubation be used to test for DA?
-simultaneous auscultation of left paralumbar fossa while someone blows air into tube
-in normal cattle, loud bubbling sounds can be heard because there is no viscous between the abdominal wall and the rumen
-in DA cattle, the bubbling sounds distant between the abomasum is between the abdominal wall and the rumen
What are the characteristics of the liptak test?
-stick a needle into the organ that is against the body wall and test pH
-abomasum will have a lower pH (3 to 3.5)
-rumen will have closer to neutral pH
What can be seen on ultrasonography on the left side that indicates LDA?
visible mucosal folds on ultrasound in a region that should be rumen
What can be seen on ultrasonography on the right side that indicates RDA?
can see the half moon shape and lots of folds that make up the pylorus in a region that should be rumen
What are the treatment strategies for LDA treatment?
*roll
-shake
-toggle
*right paralumbar fossa laparotomy
-omentopexy
-pyloropexy
*left paralumbar fossa laparotomy
-abomasopexy
*right paramedian laparotomy
-abomasopexy
*laparoscopy
What are the treatment strategies for RDA/AV?
*right paralumbar fossa laparotomy
-omentopexy
-pyloropexy
What is the supportive care for DA?
-fluid therapy
-pain management
-prokinetics
What are the principles of rolling techniques?
-gas is trapped in the abomasum
-if cow is put in dorsal recumbency, abomasum should return to original/physiological position
-true if nothing impairs abomasum’s ability to move within abdomen
What are the materials used for the roll and toggle technique?
-toggle pin set
-long rope to cast cow
-surgical scrub solutions
-possible sedatives
What is the principle of toggle placement?
placing the toggle pins into the abomasum maintains the abomasum against body wall; can get slight peritonitis and adhesions that maintain the abomasum in that position
What are the pros of the roll and toggle technique?
-short surgical time
-minimally invasive
-minimal equipment requirements
-cost efficient
-overall positive prognosis
What is the main con of the roll and toggle technique?
blind technique; possibility for perforation or entrapment of various structures
What are the potential complications of the roll and toggle technique?
-failure/redisplacement
-abomasal rupture
-local/diffuse peritonitis
-pexy of another organ
-malposition of abomasum and abomasal outflow obstruction
-fistulation along sutures/body wall cellulitis/abdominal hernia
What are the characteristics of omentopexy?
-second most common technique for correction of displaced abomasum
-always performed via right paralumbar fossa laparotomy, even for an LDA
What are the characteristics of exploratory laparotomy in cattle?
-ultimate complementary examination to get a diagnostic
-performed standing
-do not need a surgical suite, just a regular clean space
-affordable
What is important regarding anatomy when performing an exploratory laparotomy?
must go caudal to and around the omentum in order to reach any potential DA
What are the conditions required for an omentopexy?
-abomasum should be free for movement within abdomen
-cow should be able to stand throughout procedure
What is the standard approach to an omentopexy via right flank?
-decompression of gas in abomasum
-reduction of the displacement by passing abomasum under rumen
-identification of pylorus by gentle traction of greater omentum
How can the pylorus be identified during surgery?
the shiny serosal surface will be the only one visible
How is the pexy portion of the omentopexy achieved?
the greater omentum is sutured to the body wall
What is the post-op care for omentopexy?
-antibiotics
-pain management
What is the prognosis for omentopexy?
overall successful outcome in > 90% of cases
What are the potential complications that occur with omentopexy?
-recurrence of displacement
-surgical site infection
What are the characteristics of omento-pyloropexy?
-fixation of both omentum and pylorus to body wall
-suggested to have lower relapse rate
-same complications as omentopexy PLUS risk of functional physical pyloric obstruction
What are the indications for left flank abomasopexy?
-last third of gestation
-rumen bloat is an LDA
What are the contraindications for left flank abomasopexy?
-no ping
-low ping; below mid-abdomen or really cranial
-size of cow is greater than length of surgeon’s arms
What are the possible complications of left flank abomasopexy?
-entrapment of small intestine and/or omentum between abomasum and body wall
-fistulation
-surgical site infection
What is the most important aspect of a right paramedian abomasopexy?
the holding layer for the paramedian approach is the external fascia of the rectus abdominus muscle
What are the two steps of laparoscopic abomasopexy?
-one step in which animal is standing
-one step in which animal is in dorsal recumbency for toggle/abomasopexy
What is floating abomasum?
intermittent displacement of abomasum
How is floating abomasum corrected?
ex-lap with omentopexy
What is RDA?
simple dilation to the right of the abdomen
What is abomasal volvulus?
twist of the abomasum around the center axis in the lesser omentum
What are the repercussions of RDA/AV?
-alteration of vascular supply to abomasum
-increased HR
-severe dehydration
What are the treatment steps for RDA/AV?
-surgery in ALL cases
-medical support
What are the steps of a right paralumbar fossa laparotomy for RDA/AV?
-decompression of gas
-reduction of displacement/volvulus
-identification of pylorus and omentopexy
What is the prognosis for RDA/AV?
-RDA has positive outcome in 80% of cases
-AV has positive outcome in 60% of cases
-HR < 100 bpm better prognostically
-lactate values < 2 mmol/L better prognostically
-intraluminal pressure < 16 mmHg better prognositically
What are the metabolic consequences of DA?
metabolic alkalosis with paradoxical aciduria
