Anesthetic considerations in patients undergoing percutaneous radiofrequency interstitial tissue ablation.

Radiofrequency (RF) interstitial tissue ablation is a new, minimally invasive procedure for patients with liver cancer who are not candidates for conventional therapy. The percutaneous RF ablation therapy involves placing a needle electrode under ultrasound guidance into a selected portion of the tumor and heating the tissue between 90 degrees C and 100 degrees C. The ablation procedure can be done under monitored anesthesia care on an outpatient basis. The patient's ability to cooperate with regard to breathing is critical for accurate needle placement. Intravenous sedation must be meticulously titrated to maintain a delicate balance of patient cooperation and optimal comfort.