Epsilon Archive for Student Projects

Abstract

Dystocia, or difficult birth, is a commonly seen complication to natural birth in veterinary hospitals. Although other methods of resolving dystocia exist, 60 % of dystocias will need to undergo caesarean section. To perform a caesarean section, the bitch will have to undergo anesthesia.

The purpose of this literary study was to provide a deeper understanding regarding how the physiologic changes that occur during pregnancy influence anesthetic management in the bitch and puppies. Which anesthetic drugs and drug combinations indicated was also investigated as well as how a veterinary nurse can optimize care of the mother throughout the procedure and how resuscitation of the puppies should be carried out for best possible outcome.

This study, investigating concurrent literature on the subject, found that the bitch has an increased sensitivity to anesthetics subsequent to physiologic changes following pregnancy and have an increased sensitivity towards apnea and the hypoxia that follows. She is also more prone to regurgitation and aspiration due to physiologic changes in the GI-tract. Every drug administered to the bitch will cross the placenta and the same effect seen in the mother will be seen in the puppies.

Several anesthetic compounds was suggested for anesthesia in caesarean section in dogs, but protocols including acepromazine, alpha2-agonists and the combination ketamin-midazolam was found to be associated with increased puppy mortality and are hence not recommended. Analgesia was found to be a controversial subject in the concurrent literature.

Care to the mother must be taken throughout the procedure. The key points being that the mother should not be stressed and should be preoxygenated for 3-5 minutes prior to induction to prevent maternal and fetal hypoxia. The risk for regurgitation and aspiration should be minimized. Hypothermia must be prevented and the bitch should get proper pain relief before or during surgery to make her more comfortable postoperatively and allow the puppies to suckle soon after surgery.

Resuscitation of the puppies should focus on getting them warm, removing fetal membranes with towels and clear airways. Rubbing them dry vigorously, focusing on genital, umbilical and lumbar area will stimulate breathing and circulation. Intubation and ventilation may be required. Care must be taken so that drugs are not administered before circulation is sufficient.