Bovine Surgery 2 notes

Question 1

Approaches to the bovine abdomen

Answer 1

i) Flank
a. Paralumbar fossa celiotomy
i. Left
ii. Right
b. Mid to low
i. Right paracostal approach
ii. Left oblique celiotomy
c. Ventrolateral oblique
ii) Right paramedian celiotomy
iii) Ventral midline

Question 2

Flank: (a) paralumbar fossa celiotomy
- what can we access from the left side?

Answer 2

o Left side: access rumen, reticulum, spleen, diaphragm, reproductive tract, bladder, left kidney, abomasum (LDA)

Question 3

Flank: (a) paralumbar fossa celiotomy
- what can we access from the right side?

Answer 3

o Right side: access pyloric part of abomasum, small & large intestine, reproductive tract, urinary bladder, kidneys

Question 4

Flank: (a) paralumbar fossa celiotomy
Are R and L approaches the same? how do we adjust our appraoch for pyloropexy or c-section?

Answer 4

o R & L approach the same
- If pyloropexy anticipated (R side), go closer to last rib
- If c-section (L side), incision more caudal and lower in flank

Question 5

Flank: (a) paralumbar fossa celiotomy
- landmarks

Answer 5

• 6-8cm ventral to transverse processes
• 4-6cm caudal to last rib
• Dorsoventral direction for approx. 25cm

Question 6

Flank: (a) paralumbar fossa celiotomy
- layers?

Answer 6

• Skin
• Subcutaneous
• External abdominal oblique
• Internal abdominal oblique
• Transverse abdominis

Question 7

Flank: (a) paralumbar fossa celiotomy
- what is the holding layer?

Answer 7

• External abdominal oblique

Question 8

Flank: (a) paralumbar fossa celiotomy
- how do we incise the external abdominal oblique? what are its anatomic properties?

Answer 8

o Incised in same direction as skin incision
- Most extensive muscle of flank, ‘holding layer’
- Originates on 4th or 5th rib, terminates on tuber coxae, prepubic tendon and linea alba
- Fibres run in caudoventral direction
- Aponeurosis of external abdominal oblique blends with aponeurosis of internal abdominal oblique to form external sheath of rectus abdominis muscle

Question 9

Flank: (a) paralumbar fossa celiotomy- Internal abdominal oblique
- how do we incise? anatomic properties?

Answer 9

o Incised in same manner as external abdominal oblique
- Originates on tuber coxae, transverse processes and thoracolumbar fascia, terminates on costal cartilages or aponeurosis joining external abdominal oblique
- Fibres run in cranioventral direction

Question 10

Flank: (a) paralumbar fossa celiotomy- Transverse abdominis
- how do we incise? anatomic properties?

Answer 10

o Tent using thumb forceps and use Mayo scissors to cut along length to prevent damage to viscera
o Thinnest layer
o Arises from transverse processes of lumbar vertebrae and last ribs
o Forms aponeurosis at lateral edge of rectus abdominis muscle
o Becomes internal sheath of rectus abdominis muscle and ultimately inserts on linea alba
o Covered on inside by transverse fascia and peritoneum
o Closure

Question 11

Flank: (a) paralumbar fossa celiotomy
- closure technique

Answer 11

• 4 layers
  o Peritoneum & transversus abdominis, No. 1 or 2 absorbable, simple continuous
  o Internal abdominal oblique, No. 1 or 2 absorbable, simple continuous
  o External abdominal oblique, No. 1 or 2 absorbable, simple continuous
  o Skin, non-absorbable suture, No. 1 , Ford interlocking pattern and a few simple interrupted sutures at the ventral aspect to allow for drainage if necessary

Question 12

Flank: (a) paralumbar fossa celiotomy
- advantages and disadvantages

Answer 12

o Advantages to flank approach: good for exploration, viscera in normal position
o Disadvantages to flank approach: not always adequate exposure eg for evaluating gravid uterus, or small intestine; cow may go down

Question 13

Flank: (b) Mid to low: right paracostal approach
- what is it good for? how can we approach?

Answer 13

o Good for access to abomasum in calves or adult cattle
o More thorough examination of intestines possible through this approach in calves due to more mobile intestinal tract than adults
o Left lateral recumbency under GA

Question 14

Flank: (b) Mid to low: right paracostal approach
o Landmarks and layers

Answer 14

• Skin incision is made parallel and caudal to last rib (5-10 cm in adults)
  o Length depends on access needed
• Subcutaneous tissue
• Aponeurosis of external abdominal oblique, incised in direction of skin incision
• Next layer is muscular layer of internal abdominal oblique dorsally, and aponeurotic portion ventrally, incised in direction of skin incision
• Transversus abdominis and peritoneum together then tented and incised with Mayo scissors

Question 15

Flank: (b) Mid to low: right paracostal approach
- closure

Answer 15

• Layers closed individually with absorbable suture material

Question 16

Flank: (b) Mid to low: left oblique celiotomy
- reccomended for what?

Answer 16

o Recommended for cows with c section

Question 17

Flank: (b) Mid to low: left oblique celiotomy
- landmarks

Answer 17

o Skin incision starts 10cm ventral to transverse process and angles forward to finish at level of costochondral junction
o Abdominal oblique muscles incised in same direction as skin
o Transversus and peritoneum tented as other approaches

Question 18

Flank: (c) Ventrolateral oblique celiotomy
- useful for what? positioning and technique?

Answer 18

o Useful for uterus in case of emphysematous fetus
o Cow in lateral recumbency with upper leg abducted
o Incision made lateral to milk vein
o Incision extends caudally, extending dorsally, staying lateral to attachment of bladder

Question 19

Flank: (c) Ventrolateral oblique celiotomy
- layers, incision technique

Answer 19

o Skin, subcutaneous
o External rectus sheath (holding layer), rectus abdominis muscle
o Internal rectus sheath (tent and use scissors), take extreme care if gravid uterus underlying incision

Question 20

Flank: (c) Ventrolateral oblique celiotomy
- closure

Answer 20

o Closure is difficult. Use absorbable, No. 2 or 3. Continuous, simple interrupted or tension relieving sutures may be needed

Question 21

Right paramedian celiotomy
- gives access to what? uses? position?

Answer 21

o Cranial abdomen access
o Mostly used for correction of abomasal displacement or volvulus, or access to reticulum
o Restrained in dorsal recumbency

Question 22

Right paramedian celiotomy
- landmarks

Answer 22

• 4-6cm lateral to ventral midline
• 6-8cm caudal to xiphoid
• 15-20cm incision

Question 23

Right paramedian celiotomy
- layers

Answer 23

• Skin, subcutaneous
• External sheath of rectus abdominis muscle (holding layer), rectus abdominis muscle, internal sheath of rectus abdominis muscle (thumb forceps to tent)
• Sometimes in cranial portion aponeurosis of pectoral muscle is present

Question 24

Ventral midline approach
- use? incision location? closure?

Answer 24

o Can be used for c section
o Skin incision through linea alba
o 3 layer closure: linea alba (No.2 or 3 absorbable suture), subcutaneous layer, skin

Question 25

o Indications for rumenotomy

Answer 25

 Removal of metallic foreign objects that may be causing traumatic reticulitis or traumatic reticuloperitonitis
 Removal of foreign material such as bailing twine or plastic bags that may obstruct reticulo-omasal orifice
 Removal of foreign bodies lodge in distal esophagus
 Removal of ruminal content following overload, or ingestion of toxic plants
 Rumen impaction
 Impaction or atony of omasum or abomasum

Question 26

rumenototmy pre-operative planning? incision location?

Answer 26

: left flank approach, standing, local anesthesia using paravertebral block, inverted L block or line block
 Make incision close to last rib so easier to reach rumenotomy, but leave enough muscle adjacent to rib to close

Question 27

first thing to do in rumenotomy surgery after initial incision?

Answer 27

o Open and systematically examine peritoneal cavity. Palpate any adhesions but do not attempt to break down

Question 28

where do we anchor rumen in rumenotomy and why?

Answer 28

o Rumen is anchored to skin to prevent contamination of peritoneal cavity when abdomen opened:
 Exteriorise as much of rumen as possible

Question 29

technique of rumenotomy - how to exteriorise rumen

Answer 29

 Exteriorise as much of rumen as possible
 Continuous inverting suture pattern to close rumen to skin over entire incision, use non-absorbable No1 or 2, cutting needle needed for skin
 Ensure rumen projects well over skin at ventral aspect to prevent contamination
* Alternatively, can use rumenotomy board, but is more easily displaced

Question 30

how to incise rumen and explore rumen and reticulum in rumenotomy?
what do we do if we find an abscess?

Answer 30

 Incision of rumen with scalpel blade, leaving enough room ventral and dorsal for closure
 Surgeon uses plastic glove, and inside of rumen and reticulum explored, content needs to be removed, and fluid removed with hose
 Follow dorsal wall (through gas cap) to reach reticulum
* To locate foreign bodies, reticulum can be gently picked up
o If reticulum cannot be picked up likely adhesions in this area, and this may be where metallic foreign object is located
* Palpate for abscesses
o Abscess can be drained into reticulum by carrying in scalpel blade attached to umbilical tape

Question 31

rumenotomy - how do we close? considerations to avoid contamination?

Answer 31

 Closure of rumen with No. 1 or 2 absorbable material in 2 rows of continuous pattern, with second row using an inverting suture pattern
* Following closure of first row, suture line is thoroughly lavaged
* surgeon regowns, redrapes and uses a clean surgical kit
* Rumen-fixation suture removed prior to closure of second row of rumen sutures
 No further exploration of abdomen done due to risk of contamination.
 Flank incision closed

Question 32

rumenotomy possible complications

Answer 32

 Potentially fatal peritoneal contamination if not good seal between skin and rumen
 Incisional swelling and infection

Question 33

rumenostomy indications

Answer 33

(Rumen fistulation)
o Indications:
o Chronic vagal indigestion (chronic bloat)
o Nutritional research
o Collection of rumen fluid for transfaunation