Because of the insufficiency of cadaveric organs and increasing need for organs, the interest in living donor liver transplantation have been greatly increased. The relative reduction of the remaining liver after the operation in Living Liver Donors makes it difficult and compelling to choose a very effective and very safe method in the management of postoperative analgesia.

Opioids are the main agents used in the postoperative analgesia of Live Liver Donors. Opioids have serious side effects such as respiratory depression, apnea, circulatory collapse, coma, and death. Both short-term and long-term administration of opioids cause acute opioid-induced hyperalgesia.

Ketamine, an NMDA receptor antagonist, has been hypothesized to counter opioid tolerance and NMDA receptor-mediated central sensitization. Various studies and systematic reviews have shown that low-dose ketamine has an opioid-sparing effect in all surgical patients.

Although low-dose ketamine has been shown to be beneficial overall in relieving pain, it is unclear whether it has an identified benefit in hepatectomy cases. The aim of this clinical trial was to evaluate the effect of low-dose ketamine administration on postoperative analgesia in living donor liver donors undergoing right hepatectomy procedure.

Liver transplantation is the only treatment for end-stage liver failure. The insufficiency of cadaveric organs and the inability to meet the increasing need for organs with cadaveric transplantations have greatly increased the interest in living donor liver transplantation. The relative reduction of the remaining liver after the operation in Living Liver Donors makes it difficult and compelling to choose a very effective and very safe method in the management of postoperative analgesia.

Opioids are the main agents used in the postoperative analgesia of Live Liver Donors. Opioids have serious side effects such as respiratory depression, apnea, circulatory collapse, coma, and death. Both short-term and long-term administration of opioids cause acute opioid-induced hyperalgesia.

There is evidence that opioid tolerance can occur in the dorsal root ganglion through N-methyl-D-aspartate (NMDA) receptor activation. Ketamine, an NMDA receptor antagonist, has been hypothesized to counter opioid tolerance and NMDA receptor-mediated central sensitization. Low-dose ketamine is an effective adjuvant in painful orthopedic procedures that reduces pain and opioid need, especially in the first 24 hours after the procedure. Various studies and systematic reviews have shown that low-dose ketamine has an opioid-sparing effect in all surgical patients.

Although low-dose ketamine has been shown to be beneficial overall in relieving pain, it is unclear whether it has an identified benefit in hepatectomy cases. The aim of this randomized placebo-controlled clinical trial was to evaluate the effect of low-dose ketamine administration on postoperative analgesia in living donor liver donors undergoing a painful right hepatectomy procedure.

Inclusion Criteria:

• living liver donors, aged 16-65 years, who are scheduled for right hepatectomy will be included in the study.

Exclusion Criteria:

• to use opioid medications before surgery,
• trauma,
• body mass index (BMI) >35,
• unstable ischemic heart disease,
• increased intracranial or intraocular pressure,
• lactation,
• to have an allergic to ketamine, morphine, propofol or remifentanil,
• psychiatric illness, patient-controlled analgesia (PCA)
• unwillingness or inability to use the device
• inability to use the numerical rating scale (NRS).

I am hesitant to share the data before completing the study. However after end of the study I might consider sharing