The effect of local anesthetic infiltration around nephrostomy tract on postoperative pain control after percutaneous nephrolithotomy

The objective of the study was to investigate the effect of a long acting local anesthetic infiltration around nephrostomy tract on pain control after percutaneous nephrolithotomy. Forty-six patients with kidney stones of >2 cm undergoing single access subcostal percutaneous nephrolithotomy (PCNL) were enrolled in the study. Patients were randomized to levobupivacaine (Group I) and saline (Group II) infiltration groups. Group I patients (n = 23) had 75 mg/30 cc levobupivacaine infiltration around the access site after placement of nephrostomy catheter. Group II patients had 30 cc saline infiltration. Postoperatively the patients were given narcotics on demand. Pain scores were collected using a visual analog scale (VAS) at 2, 4, 6, 8, 12 and 24 h postoperatively. The VAS scores, time to analgesic demand, ambulation, and duration of nephrostomy tube were compared between two groups. The mean age was 44 and 45 years in group I and II patients. There were no significant differences between the two groups with regard to demographics, surgery or stone characteristics. Comparison of pain scores at all postoperative time points was not statistically significant between the two groups. Time to first analgesic demand and total narcotic analgesic dose per patient were 1.2 ± 1.05 and 4.04 ± 1.57 h; and 96 and 112 mg for group I and II patients (p = 0.009 and p = 0.41, respectively). Ambulation time and duration of nephrostomy tube were also similar. Infiltration of nephrostomy tract site with levobupivacaine does not have a superior effect compared to saline on postoperative pain control in patients undergoing PCNL.To prolong analgesia, the effect of intermittent tract injections or continuous infusion of local anesthetics for the postoperative maintenance of the local anesthetic effect seems worth to investigate in future studies.