Randomised, double‑blind, parallel pilot study (n=40 planned) comparing a single preoperative IV ketamine infusion (0.5 mg/kg over 40 min) versus midazolam (0.045 mg/kg) to improve perioperative depressive symptoms in surgical patients with a history of MDD.
This trial tests the feasibility and preliminary efficacy of a single preoperative sub‑anesthetic ketamine infusion (0.5 mg/kg IV over 40 minutes) compared with midazolam (0.045 mg/kg IV) given 1–3 days before surgery to reduce depressive symptoms in patients with a history of major depressive disorder.
Primary aims are feasibility of enrolment, estimate of variability in change in MADRS score at day 1 post‑surgery (≥2‑point improvement), and safety/tolerability including dysphoric reactions and need for hospitalization.
Population: adults with life history of MDD undergoing lumbar surgery; cognitive status screened with MMSE; outcomes include MADRS change, adverse events, and perioperative complications.
Single intravenous sub‑anesthetic ketamine infusion given preoperatively.
Infusion over 40 minutes given 1–3 days before surgery.
Intravenous midazolam active comparator given preoperatively.
Midazolam 0.045 mg/kg IV over 40 minutes (active comparator; compound recorded as placebo reference).