Respiratory depression in women receiving propofol/esketamine versus propofol/fentanyl for abortion surgery or curettage: a randomized clinical trial.

Summary

In 176 women undergoing abortion or curettage with propofol-based non-intubated anesthesia, subanesthetic esketamine (0.15 mg/kg) reduced intra-anesthetic respiratory depression compared with fentanyl (1 µg/kg). Secondary outcomes included vital signs and propofol dosing, supporting esketamine as an opioid-sparing analgesic adjunct in this setting.

Key Findings

• Randomized trial (n=176) showed significantly lower respiratory depression with subanesthetic esketamine (0.15 mg/kg) plus propofol versus fentanyl (1 µg/kg) plus propofol (11% vs 45%).
• Secondary outcomes included respiratory rate, pulse oximetry, hemodynamics, propofol dose, and adverse events, supporting the feasibility of an opioid-sparing approach.

Clinical Implications

For brief gynecologic procedures under propofol without intubation, substituting low-dose esketamine for fentanyl can reduce respiratory compromise. Institutions should integrate monitoring and dosing protocols while considering hemodynamic and psychomimetic profiles of esketamine.

Limitations

• Single-center peri-anesthetic study with limited generalizability beyond specific procedures and demographics
• Blinding and allocation concealment details not provided; comprehensive safety endpoints (e.g., emergence phenomena) not fully reported in abstract

Future Directions

Multicenter, blinded RCTs comparing esketamine- versus opioid-based adjuncts across procedures, with standardized definitions of respiratory depression and comprehensive safety/experience outcomes.