The Use of S Ketamine Versus Placebo During Target Controlled Intravenous Anaesthesia to Reduce Morphine Consumption and Side-Effects After Abdominal Hysterectomy: A Randomized Control Trial

In recent times it has been suggested that NMDA receptor antagonist like ketamine when used in small doses helps reducing postoperative pain and opioid consumption without compromising wakefulness and or causing its psycho mimetic adverse effect .

The clinical utility of S+ ketamine as an adjuvant intra-operatively remains controversial. The NMDA receptor activation and subsequent biochemical process has been proven to play an important role in both hyperalgesia after tissue injury and the development of opioid tolerance. Various studies have reported the advantage of S+ ketamine over traditional balanced anaesthesia, but may lead to secondary hyperalgesia and increased opioid requirement in post operative period in both animals and healthy human volunteers. Other studies showed that 48 hours continuous administration of small-dose ketamine, together with patient-controlled analgesia (PCA) with morphine, or systemic, epidural co-administration of ketamine and opiates markedly reduced cumulative morphine. However, the dosage, route and timing of administration of S+-ketamine varied in different setting.