Species: Feline   |   Classification: Techniques

Introduction Requirements Preparation Procedure Aftercare Outcomes Further Reading

Introduction

  • Surgical management of dystocia.

Uses

Maternal dystocia

  • See Dystocia maternal Dystocia: maternal.
  • Prolonged gestation due to single fetus syndrome.
  • Partial primary uterine inertia which is unresponsive to medical management.
  • Secondary uterine inertia.
  • Unmanageable obstruction of birth canal, eg pelvic fracture.
  • Uterine anomaly, eg torsion, inguinal herniation of gravid uterus.

Fetal dystocia

  • See Dystocia fetal Dystocia: fetal.
  • Relative or absolute fetal oversize.
  • Irreduceable malpresentation or malposture.
  • Fetal death/putrefaction/mummification.
  • Signs of fetal distress in prolonged or difficult parturition.
  • Fetal deformity, eg fetal monster.

Elective

  • History of previous dystocia.
  • Predictable dystocia associated with breed type.

Advantages

  • Increased chance of live young following rapid removal of viable fetus/es.

Disadvantages

  • Care required to prevent fetal hypoxia.
  • Cost.

Alternative Techniques

Medical management

  • Sedation Sedation or sedative protocol for, eg neurogenic inhibition of second stage labor.
  • Oxytocin Oxytocin for, eg non-obstructive dystocia with dilated cervix.
    Risk of premature placental separation and uterine friability.
  • Calcium gluconate Calcium gluconate for, eg primary uterine inertia due to subclinical hypocalcemia Hypocalcemia.

Mutation and traction

  • If reduceable malposture.
  • If marginal fetal oversize without uterine inertia.
  • If last fetus in cases of uterine inertia.

Decision Taking

Criteria for choosing test

General considerations

  • Objective evaluation of indications for surgical intervention not always possible.
  • Often difficult to assess cause of dystocia.
  • Considerable range in normal interval between expulsion of fetuses (5 min-7 days).
  • Decision often a subjective assessment of behavioral signs and experience.

Diagnosis of dystocia

  • Prolonged gestation >65 days after first copulation.
  • Persistent labor efforts >3 hours (difficult to assess onset of 2nd stage of partus) without expulsion of fetus.
  • Weak and infrequent labor efforts which fail to produce fetus within 2-3 hours.
  • Absence of labor efforts for longer than 4 hours between births (there can be breaks of 1-7 days between the birth of live kittens making this decision difficult in practice).
  • Physical examination, eg pelvic obstruction.
    This is difficult to assess in the absence of overt obstruction such as fractures and displacement of pelvic bones. Even X-rays may not reveal fetal-pelvic disproportion accurately or reliably.
  • Signs of systemic illness, eg toxemia, fever, depression, weakness.
  • Evidence of fetal death on ultrasonography Abdomen: normal pregnancy - ultrasound 01  Abdomen: normal pregnancy - ultrasound 02 .
  • Abnormal vulval discharge (normal vulvar discharge in cats is reddish-brown not greenish as in bitches).

Requirements

Personnel

Anesthetist expertise

  • See anesthesia for cesarean section Anesthesia: for Cesarean section.
  • If fetuses are demonstrably viable via ultrasonography Abdomen: normal pregnancy - ultrasound 01  Abdomen: normal pregnancy - ultrasound 02 or radiography Uterus: normal pregnancy (near term) - radiography , and live delivery is desirable, care must be taken to prevent fetal hypoxia.
  • Fetal hypoxia may result from premature placental separation, impaired maternal ventilation or drugs.
  • Most sedative, narcotic and anesthetic agents cross placenta, muscle relaxants do not.

Other involvement

  • As many personnel as possible to manage neonates.

Materials Required

Minimum equipment

Ideal equipment

  • Suction to clear airways of neonates.
  • Incubator, adrenaline and doxapram Doxapram
  • Towels to dry and warm neonates.

Preparation

Pre-medication

  • Avoid sedative or narcotic drugs.

Site Preparation

  • Either Flank: avoids damage to mammary vessels and post-operative wound interference by young.
  • Or Ventral midline: tilting patient in dorsal recumbency relieves respiratory embarrassment, alleviates caval occlusion, gives best access to gravid uterus Laparotomy: midline Laparotomy: flank.

Preparation

  • Standard aseptic.

Restraint

Other Preparation

Procedure

Approach

Step 1 - Ventral midline laparotomy

Tilting patient relieves respiratory embarrassment and alleviates caval occlusion.
  • Incise skin.
  • Make laparotomy exposure large enough only for uterine access.

Core Procedure

Step 1 - Inspect and exteriorize uterus

  • Inspect uterus for signs of rupture or fetal death .
  • May elect for ovariohysterectomy Ovariohysterectomy.
  • Carefully exteriorize.
    Sudden exteriorization may result in transient fall in blood pressure.
  • Pack off uterus from abdominal cavity with warm moist towels.

Step 2 - Incise uterus

  • Make longitudinal incision at uterine bifurcation.

Step 3 - Removal of young

  • 'Milk out' fetuses through single incision. If required, make two incisions (modal litter size is 4).
  • Perforate fetal membranes.
  • Clamp umbilicus before sectioning.
  • Keep all neonates warm and monitor carefully.
    Ensure all fetuses removed, first the fetus causing dystocia.

Step 4 - Inspect placenta

  • Presence of placenta with fetus often indicates fetal death.
  • Remove placenta if free; leave if still tightly attached.

Step 5 - Uterine closure

  • Suture (absorbable sutures) using inverting or appositional pattern.
    No real rationale for double layer of sutures.Ovariohysterectomy usually not performed as elective procedure at this stage unless uterine disease. Fetal death is very common and not generally an indication for hysterectomy.

Exit

Step 1 - Standard laparotomy closure

  • Same as laparotomy Laparotomy: midline.
    Cuticular or silk sutures may minimize neonate-initiated wound complications.

Aftercare

Immediate

Fluid requirements

  • Intravenous fluids if prolonged dystocia.

General Care

Neonatal care

  • Pass each neonate to assistant to be towel-dried vigorously.
  • Aspirate fluids from fetal airways.
  • Massage neonate to promote respiration.
  • Maintain in warm dry environment, eg incubator at 36°C. Best in radiant lamp with high temperature or 36°C and cool areas in cage of 24°C. Avoid overheating.
    Sucking may be delayed for up to 6 hours post-partum without detriment.
  • Return neonates to mother on recovery.

Other medication

  • Ergonovine or oxytocin Oxytocin may help control hemorrhage.

Outcomes

Complications

  • Diarrhea: not uncommon, probably from eating placenta(e).

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Skarda R T (1999) Anesthesia case of the month - dystocia, cesarean section and acupuncture resuscitation of newborn kittens. JAVMA 214 (1), 37-39 PubMed.
  • Greene S A (1995) Anesthetic considerations for surgery of the reproductive system. Semin Vet Med Surg Small Anim 10 (1), 2-7 PubMed.
  • Tranquilli W J (1992) Anesthesia for cesarean section in the cat. Vet Clin North Am Small Anim Pract 22 (2), 484-486 PubMed.
  • Gilroy B A, DeYoungD J (1986) Cesarean section - anesthetic management and surgical technique. Vet Clin North Am Small Anim Pract 16 (3), 483-494 PubMed.
  • Benson G J, Thurmon J C (1984) Anesthesia for cesarean section in the dog and cat. Mod Vet Pract 65 (1), 29-32 PubMed.
  • Dodman N H (1979) Anesthesia for cesarean section in the dog and cat - a review. JSAP 20 (8), 449-460 PubMed.