Obstetrics Flashcards
Mare pelvic inlet
Round
Little advantage by fetal rotation as it passes through the birth canal
Dystocia
When first or second stage of parturition is difficult or impossible for the dam without assistance
Presentation
The relationship of the long axis of the fetus to the long axis of the dam
Anterior, posterior, or transverse
Position
Relationship of dorsum of the fetus to the quadrants of the dams pelvis
Dorso- sacral (norm), pubic (upside down), ileal (left or right)
Posture
Relationship of the fetus extremities to its own torso
Lateral flexion of the head and neck
Flexion: carpal, shoulder, hock, hip or nape
Fetus is engaged in the pelvis
Entered the pelvis with her early delivery attempt, prevented from making further progress by postural problems
Wedged tightly or fills the available space and blocks from accomplishing mutation
_______________ is necessary to gain room to do mutations
Cranial repulsion
Mutation
Operations where the fetus is returned to a normal presentation, position, or posture by repulsion, rotation, version and adjustment or extension of extremities
Repulsion/ retropulsion
Pushing the fetus cranially out of the birth canal to the abdominal cavity (gentle slow pressure)
Forced extraction
Withdrawal of the fetus from the dam through the birth canal by outside force or traction
Anterior (3 point traction)
Posterior (2 point traction)
Mare side Vet concerns
Mare too big: arm too short (warm blood and draft mares)
Mare too small :arm too big (miniature horses and donkey)
Checking for viability in anterior presentation
Pressure on eyelid (blink or move from pressure)
Finger on mouth of fetus (suckle reflex)
Pull on a limb (pullback/ resistance)
Coronary band if fetus non-responsive (pinch with Kelly forceps)
Check for viability in the posterior presentation
Check anal sphincter tone (move away?)
Pressure to rear limbs
1st degree of perineal lacerations (soft tissue trauma)
Disruption of dorsal vulva
Anal sphincter and perineal body are intact
2nd degree of perineal lacerations (soft tissue trauma)
May or may not be disruption of dorsal vulva
Disruption of the perineal body
3rd degree of perineal lacerations (soft tissue trauma)
Disruption of the vulva perineal body and anal sphincter
Allow bruised tissue and inflammation to subside: repair earliest 1m (rectovaginal fistula repair)
How is resolution achieved?
Mutation
Repulsion (+ rotation, version, extension and adjustment of the extremities)
Forced extraction
Why is lubrication important?
Allantois fluid eliminated
Recreate an interface between fetus and uterus before mutations or extractions to avoid damage/ rupture
What tool is used for rotation?
Placement of the detorsion rod
Rotation
Turning of the fetus on its long axis to bring the fetus into a dorsal-sacral position
Version
Rotation of the fetus on its transverse axis into an anterior or posterior presentation
Kuhn’s Crutch
When arm is too short
Extension for a shoulder or hip flexion or lateral flexion of the head and neck in a big mare
Shoulder and hip flexion and resolution
If anterior: turn a shoulder flexion into a carpal flexion
If posterior: turn a hip flexion into a hock flexion
Draw the joint above the fetlock towards you
Eye hook placement
Place hook 1 to medial bony canthus of the harder to reach eye, the hook 2 onto the opposite medial bony canthus
Field anesthesia
IV catheter placed outside of dystocia
Xylazine then ketamine
Maintain on triple-drip
C-section
Delivery of the fetus (usually @ term) by laparohysterotomy
Fetotomy
On fetus to reduce size by division or removal of certain parts
Partial most common, must establish fetal death
Equipment for fetotomy
OB chains and chain handles (stainless steel)
Utrecht fetotome
Wire the reader, introducer and wire handles
Gigli wire/ saw wire
Lubricant
Eye hooks
Krey hook
T/F: evaluation of fetal viability after fetotomy
FALSE
before
Complete fetotomy (anterior presentation)
Amputation of head —> forelimb —> opposite forelimb —> transverse division of fetal trunk then unit lateral longitudinal separatism of the thoracic cage —> longitudinal division of the pelvis
Complete fetotomy (posterior presentation)
Percutaneous amputation of one rear limb —> amputation of remaining limb —> transverse division of the fetal trunk —> diagonal- longitudinal division of the fetal forepart or percutanous a,putstipj of both forelimbs
Important part of fetotomy
Leave a point of traction intact
What happens if the mare isn’t cooperating?
Anesthesia: short acting xylazine/ ketamine combo (+/- diazepam)
Epidural: xylazine/ lidocaine
