title: Thermal damage assessment of novel bipolar forceps in a sheep model of spinal surgery.
abstract: BACKGROUND
  Heat transfer from bipolar tips to adjacent tissue presents a risk of thermal injury during spine surgery.
  
  
  OBJECTIVE
  The present study was designed to determine wither bipolar forceps using a novel heat pipe thermal regulation technology resulted in decreased collateral thermal injury of adjacent tissue compared with traditional bipolar forceps (control).
  
  
  METHODS
  Eight sheep underwent multilevel laminectomy and controlled bipolar coagulation of the dorsal spinal dura mater at multiple levels using forceps with or without heat pipe technology (24 spinal segments tested; heat pipe, n=11; non-heat pipe, n=11; sham, n=2). The severity (range, 1-5) and size of thermal injury to the spinal cord resulting from forceps with vs without heat pipe were assessed via histological analysis at 8 days postoperatively.
  
  
  RESULTS
  Macroscopic occlusion of the pial vein underlying the segment of epidural coagulation occurred at surgery in 64% of segments (7 of 11) coagulated with control forceps but did not occur in any segments coagulated with heat pipe forceps (P<.005). The mean width (0.58+/-0.58 vs 1.4+/-0.77 mm; P<.05) and cross-sectional area of unintended thermal injury (1.2+/-1.7 vs 4.9+/-3.2 mm2; P<.05) were decreased in segments treated with heat pipe forceps compared with control. The severity of thermal injury was decreased in segments coagulated with (median, grade 1) vs without (median, grade 3) heat pipe forceps (P<.05).
  
  
  CONCLUSIONS
  Bipolar forceps that incorporate heat pipe technology limited thermal spread and reduced the extent of unintended injury to the spinal cord and collateral vessels.
authors.affiliation: Codman & Shurtleff, Inc, Raynham, Massachusetts, USA.
authors.forename: Ebonia W
authors.initials: EW
authors.lastname: Elliott-Lewis
authors.forename: Jacquelin
authors.initials: J
authors.lastname: Jolette
authors.forename: Jandira
authors.initials: J
authors.lastname: Ramos
authors.forename: Edward C
authors.initials: EC
authors.lastname: Benzel
mesh_terms: D000818:Animals; D002056:Burns / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D004195:Disease Models, Animal; D004564:Electrocoagulation / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D005260:Female; D006358:Hot Temperature / Q000009:adverse effects*; D007431:Intraoperative Complications / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D008866:Microsurgery / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D034561:Sheep, Domestic; D013525:Surgical Instruments / Q000009:adverse effects / Q000592:standards* / Q000639:trends; D014656:Vascular Surgical Procedures / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods