Abstract: Objective This study aims to assess the feasibility,safety and analgesic efficacy of paravertebral blockade(PVB) for percutaneous nephrolithotomy(PCNL).Methods The clinical data of 45 patients with upper urinary calculi treated by Shanghai Fourth People's Hospital affiliated to Tongji University from March 2019 to December 2020 were retrospectively analyzed.Intraoperative hemodynamic changes were observed.Through visual analog pain scale(VAS) questionnaire survey were corded the  degree of pain for establishing gravel channel,after 6 hours,and after 24 hours postoperatively,postoperative analgesic usage,hospitalization duration,postoperative complications and stone clearance rate，perioperative important parameters，adverse reactions during the operation.
Results Of all the 45 patients,the mean diameter of the stones was 2.2cm.The mean operative time was 47.6min.The mean laser lithotripsy time was 18.6min.The average VAS scores of intraoperatively and at 6 and 24 hours postoperatively were 2.7,3.5,and 2.2,respectively.No additional opioid drugs were needed 6 and 24 hours after the operation.The average hospital -in time was 6.4 d.Postoperative low fever occurred in 2 patients and amild bleeding wound appeared in 1 patient,and one had mild nausea.All of whom were cured by conservative treatment.One month after the operation,the stone clearing rate was 95.6%.Two patient had residual stone in the renal calyces after the operation,and the second stage flexible ureteroscope lithotripsy was performed to achieve stone-free.
Conclusion For patients with increased risk of complications after general anesthesia or epidural anesthesia,ultrasound guided paravertebral block anesthesia in PCNL has an ideal analgesic effect with high safety and few adverse reactions.This method reduces the need for opioids in patients undergoing PCNL,improves pain experience.

Key words: paravertebral block, percutaneous nephrolithotomy, analgesic