Oxytocin (Pitocin, Syntocinon)

Category:

• Hormone

Description:

• Pituitary hormone

Indications:

• Induction of labor

• Augmentation of labor

• Control of postpartum uterine bleeding

• Treatment of incomplete of inevitable abortion  

Contraindications:

• Significant, known, cephalopelvic disproportion

• Unfavorable fetal position or presentation which are undeliverable without conversion prior to delivery

• Cases where vaginal delivery is contraindicated (invasive cervical carcinoma, active genital herpes, total placenta previa or vasa previa)

• Obstetrical emergencies where the risk-to-benefit ratio of maternal and fetal safety favors surgical intervention

• Cases of fetal distress where delivery is not imminent

• Prolonged use in uterine inertia or severe toxemia

• Hypertonic or hyperactive uterine patterns

Precautions:

• Stimulates uterine contractions similar to normal labor.

• Overstimulation may harm mother and fetus.

• Oxytocin has an intrinsic antidiuretic effect and may lead to water intoxication when administered in large or prolonged doses.

Adverse Reactions (Side Effects):

• Maternal:

  • anaphylactic reaction

  • cardiac arrythmia, PVCs

  • nausea, vomiting

  • water intoxication

  • uterine rupture

• Fetal

  • bradycardia, PVCs, and other arrythmias

  • in the presence of significant, prolonged overstimulation of uterine contractions, may cause permanent brain damage and death

Dosage:

• Administered by injection

• Induction of labor: 

  • 0.001-0.002 units (1-2 mU) per minute, increase dose by 0.001-0.002 units (1-2 mU) every 15-30 minutes until contraction pattern has been established (generally no more than 0.02 units (20 mU) per minute

• Control of postpartum uterine bleeding: 

  • 10-40 units run in 1000mL of IV fluids (blood, plasma or crystalloid) at a rate to control uterine atony or 10 units IM following placental delivery

• Treatment of incomplete of inevitable abortion: 

  • 10 units in 1000ml IV fluid run at 0.01-0.02 units (10-20mU) [20-40 drops] per minute