Effect of low-dose esketamine on pain control and postpartum depression after cesarean section: a retrospective cohort study

Esketamine is used to control postoperative pain and reduce postoperative depression in surgical patients. This study was performed to determine the effects of esketamine on pain control as well as postpartum depression (PPD) in pregnant women who underwent cesarean section (CS).Pregnant women who underwent CS between March 2018 and February 2020 at our hospital were retrospectively reviewed. Parturients in the control group received 50 µg sufentanil citrate and 0.25 mg palonosetron hydrochloride, while those in the experimental group received additional 0.2-0.5 mg/kg esketamine. The primary outcomes included postoperative pain control according to the numeric rating scale (NRS) and the incidence of PPD according to the Edinburgh postnatal depression scale (EPDS). Multivariable linear regression analysis was performed to determine the relationship between the use of esketamine, pain control, and the incidence of PPD after CS.There were 132 parturients in the control group and 108 parturients in the esketamine group in this study. All NRS scores at rest at any time point were much lower in the esketamine group than those in the control group. Besides, NRS scores when coughing were also lower in the esketamine group within 24 hours. EPDS scores were lower in the esketamine group than those in the control group within 3 months postpartum. Esketamine acted as a protector of pain control and was confirmed to improve the incidence of PPD using multivariable linear regression. Parturients had dramatically better sleep quality within 1 week postpartum (P=0.044), and morphine consumption within 24 hours postpartum was lower in the esketamine group than in the control group (P<0.001). The quality of recovery within 3 months postpartum was also better in the esketamine group (P=0.001). A subgroup analysis of 2 subgroups divided according to the dose of esketamine was then performed, indicating no significant difference between the low-dose group and high-dose group in most included outcomes.This study confirmed the effects of esketamine on pain control and the incidence of PPD in pregnant women who underwent CS. Considering the potential adverse events, low-dose esketamine may be more suitable for pregnant women who have undergone CS.