Oxytocin Dosing at Planned Cesarean Section and Anemia

Oxytocin Dosing at Planned Cesarean Section and Postpartum Anemia: A Comparison of Two Protocols

Patient's with planned cesarean sections will be randomized to receive either standard 20 mU in 1L as a bolus following delivery of the placenta or 20 mu in 1L following delivery of the placenta plus an additional 20 mU in 1L over 8 hours.

The purpose of this study is to examine the impact of differential dose protocols commonly utilized in the post cesarean period to determine if laboratory definitions of anemia are different. Oxytocin is an antidiuretic hormone that is utilized after delivery of the fetus and placenta to contract the uterus and decrease blood loss both at the time of surgery and in the post-partum period. Here at the Penn State Hershey Medical center the investigators will use 20 units of oxytocin in a 1 L bag of LR in bolus fashion after delivery of the placenta. Other protocols use an extended course of therapy using 20 units of oxytocin in a 1 L bag of LR in a bolus plus an additional 20 units of oxytocin in a 1 L bag of LR over an 8 hour period of time.

We hypothesize that:

• Women who receive the standard 20 mU of oxytocin in 1L of LR in bolus fashion plus 20 mU in 1L over 8 hours will have a decreased reduction in pre-operative vs post-operative hematocrit and hemoglobin versus those that receive 20 mU in 1L of LR.
• Women who receive the standard 20 mU of oxytocin in 1L of LR in bolus fashion plus 20 mU in 1L over 8 hours will have decreased blood loss by weight in the postpartum period compared to patients who receive 20 mU in 1L of LR.

Inclusion Criteria:

• Planned cesarean sections for singletons at or greater than 37 weeks gestational age
• Primary or repeat cesarean section will be included

Exclusion Criteria:

• Multiple fetal pregnancies
• Hematologic disorders
• Fetal anomalies
• Pre-eclampsia. These patients are at increased risk of fluid overload and so fluid status may be affected by receiving a second bag of fluid containing oxytocin in the postpartum period.
• Known contraindication to oxytocin
• Hypersensitivity to oxytocin
• Patients who have labored and then proceed with cesarean section for any reason. Patients who have labored have had either intrinsic or extrinsic exposure to oxytocin. These patients may have decreased sensitivity to oxytocin.