Ex 3 - Obstetrics/Dystocia Flashcards
In LA, who is at highest risk for dystocia? and what is the incidence of dystocia in cows, sows, and mares?
Primiparous animals are higher risk
Cows: 3-25%
Sows: 1-2%
Mares: 4-14%
What are some causes of dystocia?
abnormal fetal orientation (3 P’s), developmental abnormalities, dead/sick fetus, obstructive
Fetal-maternal mismatch (obstructive)
Fetus is too large/dam is too small
Cattle - esp 1st time moms
Toy dog breeds
Maternal pathology (i.e. dec diameter of birth canal)
obstructive
pelvic fractures (mares)
Failure of cervical dilation
- e.g. ewes - ‘ring womb” –> perform C section
Mechanical - abnormalities of 3 P’s (obstructive)
“hip lock” - fetal hips get stuck in the birth canal, due to oblong shape of pelvis
- not seen in horses (pelvic canal shape more spherical)
Uterine inertia (obstructive)
Failure of effective 1st or 2nd stage of labor
- primary –> failure to initiate labor; bitch and sow, cows (hypocalcemia)
- secondary –> uterine fatigue following prolonged labor
Intervention - pretty straight-forward
cleanliness, lubrication, expedience (progress should be made in 20-30 mins)
PE - make sure fetus okay, make sure mom okay
formulate a plan
restraint - physical and/or chemical
Mutations (manipulations)
process by which a fetus is returned to a normal presentation, position, or posture
Repulsion (manipulations)
pushing the fetus cranially (out of the pelvic canal and into the abdomen) –> this creates more space for manipulation
Rotation (manipulations)
turning a fetus on its long axis
i.e. to move the hips of a calf fetus to avoid “hip lock”
Version (manipulations)
rotating a fetus perpendicular to its long axis
- used to correct a transverse presentation
- very difficult
- C-section may be a better choice if the fetus is still alive
Extraction
Withdrawal of the fetus from the dam using force/traction
Extraction guidelines
- 2 people
- pull during contraction
- relax b/w contraction
Indications for extraction
uterine inertia fetus not entering the birth canal epidural/general anesthesia lg fetus fetotomy - after transection of retained body part
Contraindications for extractions
abnormal 3 P’s
excessively large/deformed fetus
excessively small/stenotic cervix or birth canal
Assisted vaginal delivery
mom awake and standing or recumbent
sedation, epidural if needed
Controlled vaginal delivery
mom under GA, reduces straining and allows for repositioning of fetus
can elevate the hindquarters –. fetus naturally slides back into abdomen
no uterine contractions to help you deliver the fetus
C section
Surgical procedure
fetus removed from uterus via abdominal wall incision
*procedure of choice if vaginal delivery not possible and fetus is alive
Fetotomy
performed on a dead fetus to expedite removal from uterus –> cut fetus up into smaller pieces (reduces size –> easier to remove)
Fetotomy - pros and cons
Pros: reduces size of fetus, avoids c section, may reduce trauma to dam, less expensive than c section
Cons: may cause uterine trauma, may take a long time, req’s several ppl, potential for injury to person performing fetotomy, live/dead status may or may not be known
How do we determine if fetus is alive?
are there any fetal movements? nursing on fingers, eye reflex, pinch nose
is there a pulse? umbilical cord pulsation, heart beat
What are some complications with interventions?
metritis peritonitis retained placenta uterine, cervical, vaginal injury reduction in future fertility
What is the survival rate of neonates?
low to moderate
really depends on early recognition, duration, and type of dystocia/intervention
What is the survival rate of dam?
moderate to high
Is the dam’s future reproduction compromised?
pregnancy rate is good (in the absence of uterine/cervical trauma)
