Evaluation of the Efficacy of Bupivacaine (0.5%) alone or with Clonidine (1μg/kg) Versus Control in a Single Level Paravertebral Blockin Patients Undergoing PCNL Procedure.

Introduction: Percutaneous Nephrolithotomy (PCNL) is a widely used procedure to remove complex upper tract renal calculi by means of a nephroscope. Although less invasive, PCNL is associated with significant pain owing to soft tissue injury. Most of these patients have mild to moderately compromised renal function.