title: Hemorrhagic complications of percutaneous radiofrequency ablation for liver tumors.
abstract: BACKGROUND
  Although radiofrequency ablation (RFA) is widely accepted as a percutaneous treatment for liver tumors; serious complications may occur resulting in 0.1% to 0.5% mortality. This study analyzed the risk factors and management of hemorrhagic complications, such as hemoperitoneum, hemothorax, and hemobilia.
  
  
  METHODS
  We performed 4133 RFA treatments in 2154 patients with primary and metastatic liver tumors from February 1999 to December 2007. Of these, we enrolled patients with hemorrhagic complications and reviewed their medical records thoroughly. The risk factors for each hemorrhagic complication were analyzed using unconditional logistic regression.
  
  
  RESULTS
  Hemorrhagic complications occurred in 63 out of 4133 treatments (1.5%), including hemoperitoneum in 29 (0.7%), hemothorax in 14 (0.3%), and hemobilia in 20 (0.5%). Eleven, 8, and 4 of these patients, respectively, were categorized as major complications requiring blood transfusion or drainage. Two patients died after hemoperitoneum. Logistic regression analysis revealed large tumor size [odds ratio (OR) 1.06 per 1 mm increase in diameter] and low platelet count (OR 0.88 per 10,000/microL increase) were significant risk factors for hemoperitoneum. The location of tumor nodules was a significant risk factor for hemothorax (segment 7, OR 2.31) and hemobilia (segment 1, OR 3.30). Other factors, including the number of needle insertions or the duration of ablation, were not significant.
  
  
  CONCLUSIONS
  Although hemorrhagic complications were relatively rare with percutaneous RFA, specific treatments, such as blood transfusion and drainage, were required in some cases. Care must be taken, especially in high-risk patients.
authors.affiliation: Department of Gastroenterology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
authors.forename: Eriko
authors.initials: E
authors.lastname: Goto
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Tateishi
authors.forename: Shuichiro
authors.initials: S
authors.lastname: Shiina
authors.forename: Ryota
authors.initials: R
authors.lastname: Masuzaki
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Enooku
authors.forename: Takahisa
authors.initials: T
authors.lastname: Sato
authors.forename: Takamasa
authors.initials: T
authors.lastname: Ohki
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kondo
authors.forename: Tadashi
authors.initials: T
authors.lastname: Goto
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Yoshida
authors.forename: Masao
authors.initials: M
authors.lastname: Omata
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001803:Blood Transfusion / Q000379:methods; D017115:Catheter Ablation / Q000009:adverse effects* / Q000379:methods; D016208:Databases, Factual; D004322:Drainage / Q000379:methods; D005260:Female; D006431:Hemobilia / Q000453:epidemiology / Q000209:etiology; D006465:Hemoperitoneum / Q000453:epidemiology / Q000209:etiology; D006470:Hemorrhage / Q000453:epidemiology / Q000209:etiology*; D006491:Hemothorax / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D008113:Liver Neoplasms / Q000628:therapy*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D012307:Risk Factors