Postoperative pain is a major concern for patients undergoing Nephrectomy surgery. Pain can be associated with adverse physiological and psychological effects hampering the normal recovery process. Preventive analgesia, initiated before the surgical procedure, can theoretically reduce pain sensitization, but multiple clinical studies have failed to demonstrate convincing clinical benefit.

Buprenorphine, a derivative of the opium alkaloid thebaine, is a more potent and longer lasting analgesic. Its dissociation from opioid receptor binding is slow which probably accounts for its longer duration of action. The lack of delta receptor agonist activity may be responsible for the observation that buprenorphine is less likely to induce tolerance on chronic use.

Buprenorphine is used clinically for the treatment of moderate-to-severe pain, including perioperative analgesia. A transdermal patch formulation of buprenorphine has recently been introduced in the Indian market. Although expensive, this mode of delivery has several potential benefits over oral and parenteral administration. These include noninvasive dosing, better absorption, lack of first-pass metabolism, and steady plasma concentration. The buprenorphine patch releases the analgesic steadily over 7 days and has been successfully used to treat a variety of chronic pain conditions. However, there is limited clinical experience of its utility in postoperative pain.  

Tramadol is a centrally acting analgesic with weak opioid agonist. Its safety is well established by the fact that the clinically relevant respiratory depression is not seen with tramadol and it has low dependence and abuse potential. All these properties make tramadol as the ideal drug for the management of post-operative pain. Hence, tramadol is one of the most commonly used analgesics in post-operative period. Tramadol has good bioavailability (70%–90%); hence, it has been used for providing post-operative analgesia. It should be used cautiously in patients with renal failure due to risk of accumulation.