8 - DA surgery
objectives
describe the surgical approaches for correcting left and right displaced abdomasum and for performing an exploratory laparotomy
demonstrate the techniques for administering local and regional anesthesia of the flank
select the most appropriate surgical technique and approach based on clinical presentation
identify and justify appropriate NSAID and antibiotic choices for bovine abdominal surgeries
abomasal displacement
several forms: LDA, RDA, R abomasal volvulus
may be intermittent or partial displacement
surgery prep
maintain asepsis (not sterility)
clip
srub/wash
drape/gown
may be modified in field conditions iwthout compromising surgical goals
anesthetic options
2% lidocain
line block
simple infiltration
along planned incision line
quick, easy
may cause tissue distortion
inverted L block (reverse 7)
infiltraiton ranial and dorsal to incision
avoids edema at incision site
proximal paravertebral block
inject near spinal nerves as they emerge from foramina
complete flank anesthesia
minimal lidocaine
anesthetizes T13, L1, L2
inject at T13, L1, L2
distal (transvers) paravetertebral block
infiltration at distal ends of transverse processes
easier landmarks
more lidocaine
anesthetizes T13, L1, L2
inject at L1, L2, L4
high volume caudal epidural
flank and abdonminal relaxation
rix of ataxia
longer duration
surgery procedure
incision site
veritcal incision
hand’s width caudal to last rib
layered entry
skin
external abdominal oblique
internal abdominal oblique
transvers abdominal muscle
peritoneum
exploration
clean, gloved hand
check liver’s position
assess for adhesions or abnormal structures
surgeyr procedure
locate DA
decompress → remove gas/fluid
reposition abomasum to correct position
RDA
TRUE EMERGENCY→ rapid progression to volvulus (usually counterclockwise) → compromised blood flow, necrosis, death
non-correction
causes
excessive gas
adhesions → common after abomasopexy/hx of ulcers
torn omentum → difficult to grasp/manipulate pylorus
surgical correction
left-sided approach
abomasopexy → abomasum to body wall
right-sided approach
omentopexy → greater omentum to abdominal wall
pyloropexy → secur pyloric antrum (Sow’s ear) to body wall
ventral paramedial approach
abomasopexy → abomasum to ventral incision
blind toggle → need textbook abomasal case
pros
direct abomasum visualization
strong, secure fixation
chronic/recurrent cases
cons
dorsal recumbency → poor oxygenation
increased surgical time
greater restrain/facility requirements
other options
laparoscopic abomasopexy
minimally-invasive
reduced surgical trauma
quicker recovery, smaller incision
spiker tool (right flank abomasopexy)
specialized device → suture percutaneously → secure abomasum without full laparotomy
less invasive
can be performed standing
ventral blind suture
different from toggle
percutaneous placement of sutures from ventral abdomen
used when ventral access possible but laparotomy contraindicated
closure
first layer
peritoneum
transversus abdominis
may include IAO in heifers → thinner musculature
second layer
IAO (if not in 1st layer
third layer
EAO
fourth layer
skin → leave last 1” open for drainage
Post-op
monitor incision
aluminum bandage
RAV may experience prolonged recovery → vagal indigestion
medications
flunixin meglumine → SID x 3d
abx → cephalosporins (excede, excenel), penicillin
RAV
diarrhea is positive sign
hydration critical
piloerection concerning clinical sign → systemic toxemia → poor prog
complications
dehiscence
rare
related to inadqueate post op care
excessive tension on incision
infection
more common
requires vigilant wound management
may prolong recovery
peritonitis
serious risk
compromised aseptic technique/contamination during surgery