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Fetotomy in large animals
Prof. Ottó Szenci
Department and Clinic for Production Animals
Üllő
Indications for fetotomy
• Dystocia cannot be solved by manipulation and forced extraction:
– Fetotomy
– Caesarean section
• The decision depends on the fetal life and economic value
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Indications for fetotomy
• Cesarean section:
– fetus is alive and viable
• Fetotomy
– fetus is dead
Indications for fetotomy
• After examination has revealed the presence of a dead fetus, and a safe delivery obviously cannot be made by forced traction, the fetotomy should be initiated immediately
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Indications for fetotomy
• Common fault before the decision:
– application of too great and too prolonged extractive force
– in order to avoid a CS or a fetotomy: - exerting excessive mechanical extractive force (calf-puller)
Calf-puller
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Indications for fetotomy
• The single most important factor
– determining precisely the proper time to cease attempting whole delivery of the fetus per vaginum
– in some cases: difficult to make the decision
Indications for fetotomy
• Many dystocias require only partial dismemberment of the fetus
– removal of a leg
– hiplock
– abnormal fetal posture
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Advantages of fetotomy
• Rapid reduction in the size of the fetus facilitates safe delivery per vaginam
• Exposure of the dam to major abdominal surgery is avoided
• The dam is spared inhumane treatment and possible trauma associated with application of excessive force
Advantages of fetotomy
• Less aftercare is generally required
• Recovery time is shorter
• The general condition of the dam tends to remain more stable than after CS
• The monetary return is equal to that from CS
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Disadvantages of fetotomy
• May require more time to perform than a CS
• May be exhausting to the obstetrician
• The obstetrician is subjected to the risk of wound from the instrument or from a sharp fragment of fetal bone
• Dangerous to dam
Unsatisfactory results of fetotomy
• Operator’s lack of experience
• Poorly designed instruments
• Improper fetotomy technique
• The use of fetotomy only as a last option
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Perfection in fetotomy
• Correctly designed instruments
• Proper lubrication
• Technical knowledge
• Adequate training and experience
Fetotomy instruments
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Fetotomy instruments
• Thygesen fetatome • Fetotomy knife
• Saw wire • Obstetrical chain
• Wire saw handles • Chain handles
• Fetatome threader • Krey-Schöttler double hook
• Snare introducer • Eye hooks
Thygesen fetatome
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Other instruments used for fetotomy Spiral fetatome
Saw wire and a wire handle
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Handles
Simon
Schebitz
Handles
Liess
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Thygesen fetatome
• Head (hardened steel with excellent plating)
• Two barrels
• Hand-hold
• Oval ring plate: achoring the OB chain
Head (hardened steel with excellent plating)
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Fetatome threader for the insertion of the saw wire
Different cutting planes by fetotomy
Fortrunning cutting plane
Siderunning cutting plane
Backrunning cutting plane
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Zwick-Sand saw-wire introducers
Fetotomy knives
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Obstetrical chain
Krey-Schöttler double hook
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Krey-Schöttler double hook
Krey-Schöttler double hook
• Stop: prevents overclosure of the instrument
and laceration
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Eye hooks
Eye hooks
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Required assistance
• Two assistants: desirable
– control tension on the saw wire
– actual sawing
– holding secure the fetatome during the fetotomy
Instruction in use of the fetatome
• After the wire has been placed:
– tension is applied to draw the wire snugly around the fetal part
– check for proper position
– wire check: not crossed or kinked
– tension on the wire must not be relaxed during the sawing
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Instruction in use of the fetatome
• After the wire has been placed (cont.):
– during sawing: first moderately slow, short, continuous strokes with moderate pressure
– after firmly seated wires: long, continuous sawing strokes with heavy pressure
– If correctly performed: can be completed in a short time
Lubrication
• Proper lubrication is often the key to success
• Suitable lubricant
– protection to the soft tissues
– protection to the hands and arms of the obstetrician
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Fetotomy in the cow
Fetotomy in the cow
• Standing position
• Epidural anesthesia: 4-8 ml lidocaine hydrochloride
– control straining
– alleviate pain
– allow the animal to remain standing
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Epidural anaesthesia
• Single injection of local anaesthetic into the epidural space
• coccygeal and posterior sacral nerves are affected
Needle is passed downwards
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Fetotomy in the cow
• in case of recumbency : try to induce to stand
• fractious animal: combined tranquillisation and epidural anaesthesia
• recumbent cow unable to stand up: deep epidural anaesthesia (20-60 ml)
– elevation of hind quarters
A patient for fetotomy
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Types of total fetotomy:
• Anterior (longitudinal) presentation:
1. Benesch
2. Götze
3. Baier-Schaetz
Benesch-method:
1. Forelegs in the carpal joint
2. Head and neck
3. Thorax to the spinal column
4. Fetatome out of the vulva, fixed to the stump of the neck, horizontal cut
5. Evisceration
6. Thorax and abdominal slices
7. Pelvic bone between legs
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Götze-method:
1-3, 5-7: the same as in Benesch-method
4. Fetatom out of the vulva, lifting the upper laying leg out of the loop, rotation of the fetatom with 90°, fixed to the stomp of the neck, vertical cut
Baier-Schaetz-method (anterior):
1. One foreleg + head and neck
2. Other foreleg + one part of the thorax
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Baier-Schaetz-method (anterior):
3. Evisceration
4. New thorax and abdominal slices
5. Pelvic bone between the hindlegs
Types of total fetotomy :
• Posterior (longitudinal) presentation:
1. I.
2. II.
3. Baier-Schaetz
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I. method (posterior):
1. Hindlegs in the tarsal joint
2. Cranial to the pelvic inlet to the spinal column
3. Fetatome out of the vulva, lifting the upper laying leg out of the loop, rotation of the fetatome with 90°, fixed to the stump of the pelvic bone, vertical cut
4. Evisceration
5. New abdominal and thorax slices
6. Diagonal cut of the first part of the body (fetatom head fixed on one side, saw wire between the contralateral foreleg and the neck)
II. method (posterior):
1, 4-6: the same as in the I. method 2. Cut spinal column through 3. Cut pelvic bone between the legs
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Baier-Schaetz-method (posterior):
1. One hindleg with one part of the pelvic bone
2. Other hindleg with the rest of the pelvis + one
part of the abdomen
Baier-Schaetz-method:
3. Thorax + the remaining abdomen
4. Cut of the first part of the body (one foreleg
turned back + the rest of the thorax
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Baier-Schaetz-method:
5. Other foreleg + neck and head
Fetotomy in the mare
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Fetotomy in the mare
• Standing animal in a stock
• epidural anaesthesia: 4-8 ml lidocaine hydrochloride
• tranquillisation in case of need
• recumbent mare:
– general anaesthesia
– or deep epidural anaesthetic (20-60 ml)
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