Percutaneous computed tomography-guided renal mass radiofrequency ablation versus cryoablation: doses of sedation medication used.

To compare the amount of sedation medication administered during radiofrequency (RF) ablation versus cryoablation of small renal masses. Records were retrospectively reviewed in patients who underwent percutaneous computed tomography-guided RF ablation and cryoablation of small renal masses from January 2002 to June 2011 for patient and tumor characteristics, amount of medications used for moderate sedation, and complications. Sedation was performed by giving patients titrated doses of midazolam and fentanyl. Additional medications were given if the desired level of sedation was not achieved. There were 116 patients who underwent 136 ablation procedures; 71 patients underwent RF ablation, and 65 patients underwent cryoablation. RF ablation was associated with a significantly higher mean dose of fentanyl (mean dose for RF ablation, 236.43 μg; mean dose for cryoablation, 172.27 μg; P<.001). RF ablation was also associated with a higher mean dose of midazolam (mean dose for RF ablation, 4.5 mg; mean dose for cryoablation, 3.27 mg; P<.001). In the RF ablation group, two patients required additional sedation with droperidol. As a result of oversedation, two patients in the RF ablation cohort required sedation reversal with naloxone and flumazenil. None of the patients who underwent cryoablation required sedation reversal. No other sedation-related complications occurred. Cryoablation of small renal masses was performed with less sedation medication than RF ablation. This finding suggests renal cryoablation is less painful than RF ablation; however, prospective studies with validated pain scales are needed to confirm these results.