Thrifty effect of subanesthetic-dose S-ketamine on postoperative opioids and its safety and analgesic effectiveness: A prospective, triple-blind, randomized controlled, polycentric clinical trial.

Subanesthetic-dose S-ketamine at 0.2-0.3 mg/kg especially the 0.3 mg/kg in general anesthesia induction can safely and effectively reduce postoperative pain and save postoperative opioid consumption.