A randomized feasibility pilot-study of intravenous and subcutaneous administration of ketamine to prevent postpartum depression after planned cesarean delivery under neuraxial anesthesia

Background: Evidence suggests ketamine may prevent postpartum depression (PPD) after cesarean delivery (CD) although intolerability and inconvenience of administration are problematic. We assessed the feasibility of studying ketamine (0.5 mg/kg, via subcutaneous injection or 40-min intravenous infusion) to prevent PPD after CD. Methods: Twenty-three women scheduled for cesarean delivery under neuraxial anesthesia were randomized to one of three groups: subcutaneous ketamine (SC Group, n = 8), intravenous ketamine (IV Group, n = 8) or placebo (n = 7). We measured depression (Edinburgh Postpartum Depression Scale [EPDS]) scores pre-operatively and at 1, 2, 21 and 42 days postoperatively. Anxiety, adverse effects, surgical site pain and analgesic consumption were also assessed. Feasibility was assessed based on acceptability, burden of disease, ability to collect study data and, tolerability of interventions. Results: Baseline characteristics of groups were similar, however, more women in the placebo group had pre-existing anxiety disorder (p = 0.03). 20.7% (25/121) of those approached consented to participate and 34.8% (8/23), of those assessed, screened positive for depression in the postpartum (EPDS > 12). PPD screening data was complete in 78.3% (18/23). No differences were observed for any adverse effect outcomes except for fewer incidences of intraoperative shivering with ketamine (SC: 25%, IV: 0% and Placebo: 85.7%, p = 0.01). No statistically significant difference in positive screening for PPD was observed (SC: 14.3%, IV: 50% and Placebo: 42.9%, p = 0.58). Conclusion: An RCT was judged to be feasible and there was no evidence of intolerability of either route of ketamine administration. Dispensing with the need for intravenous access makes the subcutaneous route a particularly attractive option for use in the postpartum population. Further examination of these interventions to prevent, and possibly treat, postpartum depression is warranted. Trial registration: NCT04227704, January 14^th, 2020.