Bovine Surgery 2 notes Flashcards
Approaches to the bovine abdomen
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
Flank: (a) paralumbar fossa celiotomy
- what can we access from the left side?
o Left side: access rumen, reticulum, spleen, diaphragm, reproductive tract, bladder, left kidney, abomasum (LDA)
Flank: (a) paralumbar fossa celiotomy
- what can we access from the right side?
o Right side: access pyloric part of abomasum, small & large intestine, reproductive tract, urinary bladder, kidneys
Flank: (a) paralumbar fossa celiotomy
Are R and L approaches the same? how do we adjust our appraoch for pyloropexy or c-section?
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
Flank: (a) paralumbar fossa celiotomy
- landmarks
- 6-8cm ventral to transverse processes
- 4-6cm caudal to last rib
- Dorsoventral direction for approx. 25cm
Flank: (a) paralumbar fossa celiotomy
- layers?
- Skin
- Subcutaneous
- External abdominal oblique
- Internal abdominal oblique
- Transverse abdominis
Flank: (a) paralumbar fossa celiotomy
- what is the holding layer?
- External abdominal oblique
Flank: (a) paralumbar fossa celiotomy
- how do we incise the external abdominal oblique? what are its anatomic properties?
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
Flank: (a) paralumbar fossa celiotomy- Internal abdominal oblique
- how do we incise? anatomic properties?
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
Flank: (a) paralumbar fossa celiotomy- Transverse abdominis
- how do we incise? anatomic properties?
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
Flank: (a) paralumbar fossa celiotomy
- closure technique
- 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
Flank: (a) paralumbar fossa celiotomy
- advantages and disadvantages
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
Flank: (b) Mid to low: right paracostal approach
- what is it good for? how can we approach?
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
Flank: (b) Mid to low: right paracostal approach
o Landmarks and layers
- 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
Flank: (b) Mid to low: right paracostal approach
- closure
- Layers closed individually with absorbable suture material
Flank: (b) Mid to low: left oblique celiotomy
- reccomended for what?
o Recommended for cows with c section
Flank: (b) Mid to low: left oblique celiotomy
- landmarks
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
Flank: (c) Ventrolateral oblique celiotomy
- useful for what? positioning and technique?
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
Flank: (c) Ventrolateral oblique celiotomy
- layers, incision technique
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
Flank: (c) Ventrolateral oblique celiotomy
- closure
o Closure is difficult. Use absorbable, No. 2 or 3. Continuous, simple interrupted or tension relieving sutures may be needed
Right paramedian celiotomy
- gives access to what? uses? position?
o Cranial abdomen access
o Mostly used for correction of abomasal displacement or volvulus, or access to reticulum
o Restrained in dorsal recumbency
Right paramedian celiotomy
- landmarks
- 4-6cm lateral to ventral midline
- 6-8cm caudal to xiphoid
- 15-20cm incision
Right paramedian celiotomy
- layers
- 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
Ventral midline approach
- use? incision location? closure?
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
o Indications for rumenotomy
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
rumenototmy pre-operative planning? incision location?
: 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
first thing to do in rumenotomy surgery after initial incision?
o Open and systematically examine peritoneal cavity. Palpate any adhesions but do not attempt to break down
where do we anchor rumen in rumenotomy and why?
o Rumen is anchored to skin to prevent contamination of peritoneal cavity when abdomen opened:
Exteriorise as much of rumen as possible
technique of rumenotomy - how to exteriorise rumen
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
how to incise rumen and explore rumen and reticulum in rumenotomy?
what do we do if we find an abscess?
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
rumenotomy - how do we close? considerations to avoid contamination?
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
rumenotomy possible complications
Potentially fatal peritoneal contamination if not good seal between skin and rumen
Incisional swelling and infection
rumenostomy indications
(Rumen fistulation)
o Indications:
o Chronic vagal indigestion (chronic bloat)
o Nutritional research
o Collection of rumen fluid for transfaunation
