Ketamine Pharmacokinetics and Pharmacodynamics for Postpartum Depression and Pain After Cesarean Delivery

The purpose of this study is to identify pharmacokinetics of postpartum ketamine infusion. This study will assess ketamine kinetics and metabolism in this setting. Ketamine is expected to exert different kinetics during the physiologic state of post-pregnancy. The goal in conducting this study is to better understand the pharmacokinetics and pharmacodynamics of postpartum ketamine infusion. A secondary goal is to compare these kinetics to reproductive age matched controls and to assess sex differences in ketamine pharmacokinetics. The peripartum group of this study will receive ketamine after cesarean delivery, while the control group will consist of non-pregnant female subjects and male subjects receiving the same infusion protocol.

Peripartum Participants: Inclusion Criteria * Cesarean delivery * Adults 18 years and older * Term delivery ≥ 37 weeks gestation anticipated at time of delivery * ASA PS 2 or 3 * Able to provide informed consent * One of the following must be met for inclusion: Not planning to breastfeed OR ketamine use indicated for pain management plan. Exclusion Criteria * Patient going under general anesthesia for cesarean delivery * Allergy to study medication (ketamine) * ASA PS 4 + * Contraindications to neuraxial anesthesia * Preterm delivery (\