title: An increase in body temperature during radiofrequency ablation of liver tumors.
abstract: Radiofrequency ablation (RFA) therapy using an active needle electrode inserted into liver tumors has been used clinically. To avoid hyperthermia, we investigated the relationship between the total output energy of the applied radiofrequency wave and changes in body temperature (BT) in patients receiving RFA. Fifteen patients undergoing RFA of liver tumors with general anesthesia were enrolled. The total output energy of radiofrequency waves was calculated from the power and duration of RFA. Changes in rectal (T(rect)) and tympanic temperatures were measured throughout the study. The mean number of liver tumors per patient was 1.7 +/- 1.3. The mean RFA time was 30.0 +/- 26.3 min. The mean total output energy was 125,935 +/- 114,506 J. The mean value of T(rect) increased from 36.3 degrees C +/- 0.5 degrees C to 37.0 degrees C +/- 1.0 degrees C (P < 0.01). A linear correlation was obtained between the total output energy and the changes in T(rect), indicating that T(rect) increased approximately by 1 degrees C for every 3000 J/kg of total output energy. The increase in BT during RFA of liver tumors under general anesthesia is predictable. Close observation of total output energy delivered and BT are required, and preparation of cooling measures is important, in RFA of liver tumors.
  
  
  CONCLUSIONS
  The increase in body temperature (BT) is predictable during radiofrequency ablation (RFA) of liver tumors under general anesthesia. Close observation of total output energy delivered and BT are required, and preparation of cooling measures is important, in RFA of liver tumors.
authors.affiliation: Department of Anesthesiology, Kurume University School of Medicine, Asahimachi 67, Kurume, Fukuoka 830-0011, Japan. mmss416@hotmail.com
authors.forename: Maiko
authors.initials: M
authors.lastname: Sawada
authors.forename: Seiji
authors.initials: S
authors.lastname: Watanabe
authors.forename: Hideaki
authors.initials: H
authors.lastname: Tsuda
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Kano
mesh_terms: D000368:Aged; D000768:Anesthesia, General; D001831:Body Temperature / Q000502:physiology*; D017115:Catheter Ablation / Q000009:adverse effects*; D005260:Female; D005334:Fever / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged