Oxytocin Infusions and Blood Loss in Patients Undergoing Elective Cesarean Delivery.

Effects of Different Oxytocin Infusions on Blood Loss and Postpartum Hemoglobin Values in Patients Undergoing Elective Cesarean Delivery

Although prior dose-finding studies have investigated the optimal bolus dose of oxytocin to initiate adequate uterine tone, it is unclear what oxytocin infusion regimen is required to maintain adequate uterine tone after delivery. The study investigators aim to compare two different infusion rates of oxytocin to assess the optimal infusion regimen for reducing blood loss in women undergoing elective Cesarean delivery.

Oxytocin (pitocin) is a drug commonly used in obstetric practice, and the drug effect is to increase the muscular tone of the uterus to reduce uterine bleeding after neonatal delivery. Pregnant patients undergoing elective (scheduled)Cesarean delivery routinely receive oxytocin after delivery of the baby. Post-delivery, oxytocin is commonly administered as an IV bolus and/or infusion. No previous studies have accurately assessed differences in oxytocin infusions after delivery in patients undergoing elective cesarean delivery. Thus the study aim is to investigate which infusion rate can optimally provide adequate maintenance of uterine tone during Cesarean delivery while being associated with minimal or no maternal side-effects.

Oxytocin Infusion 15 U/hr to begin after the delivery of the fetus and to terminate at the time of patient discharge from the post-anesthesia care unit.

Oxytocin infusion 2.5 U/hr to begin after the delivery of the fetus and to terminate at the time of discharge from the post-anesthesia care unit.

Patient will receive a blinded infusion of oxytocin after the time of delivery of the fetus which will terminate at the time of discharge from the post-anesthesia care unit.

Blood loss will be measured volumetrically (based on measured volume of blood within the suction chamber) and gravimetrically (based on blood weight on blood soaked laps).

Inclusion Criteria: Healthy pregnant patients with uncomplicated pregnancies: ASA (American Association of Anesthesiologists) class 1 or 2 patients. Singleton pregnancies. Exclusion Criteria: ASA class 3 or 4 patients. Known drug allergy to intravenous oxytocin. Significant medical or obstetric disease. Known uterine abnormality. Known placental abnormality.