TREATMENT TACTICS
With dystocia, you need to ascertain what clients want and what they can afford. How important are live pups to them? Cesarean
section is a tool for producing live pups, and if clients want live pups, you should not delay in doing it. But if they can't
afford it, you can try other techniques such as oxytocin and fetal manipulation.
Oxytocin
You have several options for managing dystocia. Oxytocin can be used as the first line of treatment for primary uterine inertia,
but most bitches will not respond to it. You will generally have to do a cesarean section to address primary uterine inertia.
Secondary inertia without fetal malposition or fetal distress can be hard to sort out. The bitch could be taking a break,
but if it's been more than four hours since the birth of the last puppy, it's probably uterine inertia.
If oxytocin administration isn't contraindicated after I've performed a vaginal exam and radiography (e.g. no narrowed birth canal or fetal malpositioning), then I administer up to two doses, 20 minutes apart. I use small doses
because it decreases blood flow to the fetus (e.g. 0.5 units for a Chihuahua and 2 to 3 units for a Newfoundland subcutaneously or intramuscularly). The uterus becomes refractory
to oxytocin after a few doses, so you need to do a cesarean section for larger litters (or if two doses don't produce contractions
and a puppy).
Fetal manipulation
If there is absolute fetal oversize or inadequate pelvic diameter, do a cesarean section. If there is only one large pup in
the canal, you can try to manipulate it. If you detect fetal malposition, use gentle manipulation with your fingers around
the pup's neck or shoulders (you need long fingers for this). And use lots of lubricant. You may be able to push them from
behind by using abdominal palpation or use one finger rectally and one vaginally. Use slow steady traction, and warn anyone
in the room that fetal dismemberment could occur despite your care. Above all, don't waste time. Each puppy is valuable to
the breeder.
Cesarean section
Cesarean section is indicated if you detect fetal distress on ultrasonography, uterine inertia does not respond to oxytocin,
or fetal oversize or malposition or vaginal obstruction exists. If you do a cesarean section, plan ahead. You need to limit
the time the bitch spends in dorsal recumbency so she experiences no further decrease in ventilation. And limit the time from
anesthetic induction to pup removal. Don't induce anesthesia before you're scrubbed and ready to do surgery. Have all your
equipment ready and adequate staffing on hand.
Administer intravenous fluids to the bitch. I give atropine as a premedication to support the maternal and fetal heart rate.
For anesthesia, propofol and isoflurane (or sevoflurane) are best. You can also do a line block with bupivacaine. You can
give the bitch an opioid once the pups are removed (oxymorphone, hydromorphone, or morphine).
Delivery and postoperative care
Vigorous stimulation and oxygen administration are the best techniques to revive the puppies once they're removed. You can
suction the oropharynx to remove fluid, but don't swing the puppies; it can cause brain damage, and you could throw them.
If the puppies aren't breathing and the bitch has been given opioids, administer one drop of naloxone and doxapram sublingually.
Be patient; you should try to revive them for 15 to 20 minutes before you give up. For postoperative pain, prescribe tramadol
for the bitch.
PROSPECTIVE PREGNANCIES
For subsequent pregnancies, a vaginal delivery can be attempted, especially if the problem was due to big pups. In this situation,
advise the breeder not to overfeed the bitch so the pups aren't so big. Patients with secondary uterine inertia tend to have
it again. And if the bitch experienced primary uterine inertia, she'll most likely need a cesarean section for subsequent
deliveries.
Scott Shaw, DVM, DACVECC
Department of Clinical Sciences
Cummings School of Veterinary Medicine
Tufts University
North Grafton, MA 01536
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