CONCLUSION
urolithiasis
UROLITHIASIS, COMPLICATION
This study demonstrated that using bupivacaine with or without fentanyl in spinal anesthesia provided a reliable sensory and motor block level in patients with urolithiasis who were candidates for TUL. However, the addition of intrathecal fentanyl was associated with a lower incidence of stone retropulsion. The factors affecting the occurrence of this complication and the effect of anesthetic drugs on the success rate of surgery should be considered.