Holmium:YAG lithotripsy of uric acid calculi.

PURPOSE: Holmium:YAG lithotripsy of uric acid calculi produces cyanide. We review our experience with holmium:YAG lithotripsy of uric acid calculi to determine if there is any clinical evidence of cyanide toxicity.

MATERIALS AND

METHODS

A retrospective analysis of all of our cases of holmium:YAG lithotripsy of uric acid calculi was done. Anesthetic and postoperative data were reviewed.

RESULTS

A total of 18 patients with uric acid calculi were treated with holmium:YAG lithotripsy by ureteroscopy (5), retrograde nephroscopy (2), percutaneous nephrolithotomy (5) or cystolithotripsy (6). No patient had increased end-tidal carbon dioxide, changes in electrocardiogram or significant decrease in postoperative serum bicarbonate. An 84-year-old woman had decreased diastolic pressure of 30 mm. Hg while under general anesthesia. No cyanide related neurological, cardiac or respiratory complications were noted.

CONCLUSIONS

There were no obvious cyanide related complications from holmium:YAG lithotripsy of uric acid calculi. These data suggest no significant cyanide toxicity from holmium:YAG lithotripsy of uric acid calculi in typical clinical settings. Animal studies are warranted to characterize the risk.