MSAT - Bovine REPRO Flashcards
Describe what positioning means in obstetrics
- Positioning
–> 4 quadrants: Sacrum, right ileum, pubis and left ileum
Normal: Dorsosacral
Possible positions: Dorsosacral, right/left dorsoilial, dorsopubic, right/left cephaloilial
How can posture be described in obstetrics
Posture:
–> Foetal extremities to its own body
Limbs: Can be flexed or extended
Head: Retained right or left or above or below foetus
What is the normal presentation, position + posture in mare/cow?
Cranial-longitudinal presentation, dorsosacral position, with head, neck and forelimbs extended
What are some causes of ineffective labour?
Aetiology:
* Incomplete dilation of the cervix: hormonal dysfunction, hypocalcaemia, cervical adhesions, fibrosis, premature parturition/abortion, uterine torsion.
Treat: Uterine relaxant –> Isoxsuprine, clenbuterol.
Correct uterine torsion if present, administer Ca if hypocalcaemia is present. Correct any malposition. Caesarian if cervix fails to dilate.
- Uterine inertia: inadequate uterine contractions –> failure to expel foetus.
Enlarged uterus, hypocalcaemia, pregnancy toxaemia, poor BCS, stress, premature birth, dystocia
Treat: Correct malpositiom, treat with Ca is hypocalcaemia, diagnostic traction, oxytocin, antibiotics - Uterine rupture: Emphysematous (damaged lungs) foetus, hydrops allantoios, uterine adhesions, excessive traction, retropulsion of a foetus
Treat: Repair if small tears, caesarian
Diagnose: Detection of viscera/intestines within uterus, uterine tear, extrauterine displacement of foetus, haemorrhage, peritonitis - Constriction of vulva, vestibule and vagina: common in fat heifers, calving duction treatment before softening of vaginal canal, premature delivery or abortion.
Treat: Lubrication, gentle traction + episiotomy, ceasarian - Deformities of birth canal
What are factors influencing ease of passage through maternal pelvis?
- Pelvic Size: Age, breed, weight, genetics, nutrition, gestation length
- Foetal size: Genetics, sex, gestation length, litter size, nutrition
What are clinical signs of foetopelvic disproportion?
- Prolonged labour
- Incomplete delivery of foetus
- Persistent straining without progress.
- Inability to deliver with mild traction
- Malpresentation of foetus due to insufficient room within vaginal canal: E.g. lateral deviation of head, retention of forelimb
Recumbency
How can you treat foetopelvic disproportion?
- Determine viability and health of dam
e.g. if they are recumbent + unable to walk, emphysematous foetus - Apply copious lubrication
- Correct any malpresentation
- Apply diagnostic traction
- Foetotomy, caesarian
Epidural for pain relieaf
Episiotomy: To avoid rupture of the vulva and perineum.
Hiplock: Occur following delivery of the cranial part of the foetus.
Repel foetus caudally, rotate and deliver. If dead: repel, transect, bisect pelvis & deliver each limp individually
What are the abnormalities of posture that can cause dystocia?
- Carpal flexion: One foot and head presented at vulva
Correction: Repel foetus & shoulder of displaced limb.
Grasp metacarpus of affected limb, proximal to fetlock.
Flexed carpus is elevated dorsally, laterally and repelled cranially.
When fetlock is above pubis, the foot is extended, while cupping hand under foot to protect uterus/vaginal wall.
OR with aid of rope snare:
- A rope snare distal to the fetlock can be used in extending the carpus.
The carpus is repelled while the digits are drawn into the pelvis.
If mutation is not possible: foetotomy at the distal row of carpal bones. Distal portion of the limb is removed prior to foetal extraction.
Needs to be at distal row as if it is above the carpus there is no anchor point for ropes/chains.
If it is proximal or distal to the carpus the bone stump may also lacerate the uterus/vagina.
- Elbow lock: Incomplete elbow extension: Muzzle overlies fetlocks instead of proximal metacarpal bones
Repel the foetal body while applying longitudinal + dorso-medial traction to the forelimb.
This elevates the elbow above the pelvic inlet, allowing extension of the limb - Shoulder flexion: Head and 1 limb present at vulva or external to vulva if unilateral.
If bilateral shoulder flexion: foetal head protruding outside of the vulva.
Check viability of foetus (eye reflex, suckling reflex, heart beat)
Place a snare on head prior to repelling it, allowing it to be retrieved later.
Repel foetus.
Covert to carpal flexion: extend radius. Then correct carpal flexion
If difficult manually: Rope around the flexed limb, apply traction to limb as foetus is repelled to convert to elbow/carpal flexion.
Caesarian section if live foetus cannot be repelled sufficiently.
If foetus is dead: Removal of head and neck with foetotomy. More space to correct malpresentation.
- Foot-nape posture: One or both forelimbs lie on top of the head/neck
Repel foetus.
Grasp affected fetlock, move it laterally and ventrally off the top of the foetal neck and place lateral to the head.
Raise head, apply ventro medial traction to limb to convert to normal location ventral to the head with limbs fully extended. - Displacement of head: Lateral deviation, ventral deviation, dorsal deviation
Only forelimbs located in the vaginal canal, palpation of deviated and rigid neck.
LATERAL DEVIATION:
Repel the foetus
Retraction of head into pelvis:
- Grasp the muzzle and flex the head/neck in an ark until head is directed caudally into the pelvic canal. Aligned with vaginal canal
- If muzzle cannot be reached: Grasp an ear, orbits or insert fingers into corner of mouth to draw the head caudally. Alternatively, a rope snare applied to the jaw can be used. Need to be careful to avoid fracturing lower jaw and lacerating uterus with teeth.
if head cannot be reached, pass rope around foetal neck with introducer, apply slight traction while repelling foetal body. Repeat until head can be reached
If cannot be corrected: Head/neck removal with foetotomy cut or a caesarian section
VENTRAL RETENTION:
- Both front feet present at vulva.
Mild: Nose is deviated just below pubis
Severe: Head is deviated ventrally and located between the forelimbs, adjacent to sternum
Roate head laterally in an arc before drawing the head into pelvis
Bilateral carpal flexion also present: Correct head posture first before correcting limb posture.
In some cases: repulsion alone may correct
DORSAL RETENTION: Rare
Convert to lateral deviation of the head and then correct this.
- Hock flexion: Tail protrude from vulva, flexed hocks are either at pelvic inlet or impacted within pelvis.
If one hock flexed: The other hind leg may extend through vulva.
Repel foetal hind leg
Grasp metatarsus, repel limb cranially and direct the hock laterally
Direct foot caudally and medially into pelvic canal
Grasp hoof with palm of hand to protect uterine wall as hoof is directed into the pelvic canal.
Perforation can occur with excessive force: be careful
Can use a rope snare: Repel hock and traction with rope secured above the fetlock, rope passing between the digits. Elevate foot into pelvis.
Foetus dead: Foetotomy to cut distal to the hock. Rope/chain secured proximal to hock so that traction is applied. - BILATERAL HIP FLEXION: (breach)
Foetus does not engage cervix –> No contractions.
Repel foetus cranially. Grasp tibia close to hock, flex hock and stifle by drawing tibia caudally and dorsally. Converting hip flexion to hock flexion
OR use robe: Place rope around limb dorsal or ventral to hock & apply traction caudally –> Hock flexion
Then correct for hock flexion
Fails: Foetotomy to remove hindlimb. Ensure femoral head is removed during cut
What dystocia is caused due to abnormal presentation?
- Caudal Presentation: Tail presented, soles of feet face dorsally
Differentiate from cranial dorsopubic position (as soles of feet face dorsally here too)
Treat: Diagnostic traction
Foetotomy: Remove hindlimb
C-section - Ventrovertical presentation (dog sitting): Head, neck forelimbs and distal extremities are in vagina
Head or forelegs may be protruding from vulva
Hindfeet may be palpated on pelvic brim
Difficult to correct + c-section
Hindfeet may be cupped and liften off the pelvic brim: repelled cranially into the uterus. Risk of uterine perforation near pelvic rim + usually not enough access to dislodge hind feet
If hind feet dislodged: Traction applied to head + forelegs for delivery.
ROPES/CHAINS: secured to hindfeet and front half of foetus is repelled. Creates caudal presentation with foetus in dorsopubic position.
Then foetus extracted by hind legs. Rotating foetus + Then applying traction.
If not possible: C-section + Foetotomy –> May involve transverse bi section of foetal trunk, followed by bisecting the pelvis in longitudinal plane. - Transverse dorsal presentation: Back of the calf presented towards pelvic inlet.
Head and forelimbs are in one horn.
C-section, foetotomy may be physically impossible. - Transverse ventral presentation: Rare. Attempt to grasp hind limbs, extend and rotate foetus with gentle, steady traction
How to resolve dystocia due to dorso-pubic position
- Secure limbs and head if cranial presentation
- Can attempt to rotate foetus or use a detorsion rod but be careful not to induce uterine torsion
- May infuse fluid, lubricant into uterus to aid with rotation
- Alternatively apply diagonal traction to rotate foetus: to limbs and head as foetus advances.
What is the percutaneous classical foetotomy: Cranial presentation?
6 cuts, 7 pieces
- Removal of head (1 cut, 1 piece)
- Remove of both fore limbs (2 cuts, 2 pieces)
- Foetal trunk (2 cuts, 2 pieces)
- Bisection of pelvis (1 cut, 2 pieces)
Modified:
3 cuts, 4 pieces
- Removal of head and one forelimb (1 cut, 1 piece)
- Evisceration of thorax & abdomen
- Cutting of foetal ribs + collapse of thorax
Foetal trunk: 1 cut/piece or 2 cut/piece depending on how much thorax/abdomen can be accessed
- Bisection of pelvis (1 cut, 2 pieces)
How can you amputate the head?
Loop of wire placed well behind the ears,
Loop is thread under the nose and then foetome is advanced to lie behind the ears at the level of the atlanto-occpital joint.
The base of the wire loop is advanced so that it lies perpendicular to the base of the foetotome.
The head of foetome is moved ventral or ventrolateral to head of the calf. Secured to one side of the head.
The head is secured with eyehooks and fastened to the handle of the foetotome
Hand is placed over the neck stump while traction is applied to the Krey Hook and forelimbs to avoid trauma to birth canal due to bone fragments.
How to remove the foreleg?
- Head of foetotoe is located dorsal and caudal to the scapula, cartilaginous part.
- Wire is placed between the claws, extending the foreleg as the head of the foetome is advanced along the lateral aspect of the limb to the level of the scapula crest.
- Wire released, tension taken up securing the axillary region.
- Ventral part passes between the foetal elbow and thorax. Dorsal part rests medial to humeroscapular joint.
- Limb held in extension with chain/rope attached to the fetlock. Make sure foetotome remains dorsocaudal to the scapula during sawing process.
*If remnant of scapula remains, removing using dissection with a palm knife to avoid laceration to uterus.
Removing head + foreleg in on cut:
Wire is looped around neck and around one forelimb –> Dorsal + Caudal to the scapula
Barrel of foetotome placed lateral to the forelimb.
Leg extended.
Wire breakage is an issue
How to do transverse division of the trunk?
Remove cranial portion of the chest
Loop of wire is half outside the vulva, foetome is advanced 2/3 of the way along the chest.
Wire is pulled up and placed at right angle to the longitudinal axis of the foetus.
Lie foetotome slightly caudal to where the scapula is attached with wire loop located ventrally at the mid point of the sternum.
Fix Krey hook onto remaining stump of the neck to anchor to the handle of the foetotome.
Keep foetotome adjacent to foetal trunk.
Attempt cut as close to foetal pelvis as possible.
If 2nd cut is needed: Second cut: Transversely cranial to the ileum
First cut occurs caudal to where the scapula is located, wire placed midway along the sternum.
Avoid 2 cuts if possible.
Fix Krey hook to remaining stup of the vertebrae and anchor to the handle of the foetotome. Place hand on the head of the feototome to keep it adjacent to the foetal trunk.
How to bisect the pelvis?
Location of the wire is beside the tail. The head of the foetome is located adjacent to the transected lumbar vertebrae.
Cut should be two similar sized halves.
Pass wire between the hindlimbs with wire introducer. Passed dorsally over the foetal pelvis and retrieved ventrally between the hind legs. Wire loop is seated adjacent to the tail to ensure that pelvis is bisected in half.
Foetotome is placed against the stump of the lumbar vertebrae cranial to the pelvis.
Use Krey hook to anchor
