title: Multiple factors predict the risk of spinal cord injury after the frozen elephant trunk technique for extended thoracic aortic disease.
abstract: OBJECTIVE
  Spinal cord injury (SCI) after the frozen elephant trunk (FET) technique is more frequent than after endovascular aneurysm repair. This study aimed to identify risk factors of SCI after the FET technique.
  
  
  METHODS
  We performed the FET technique for extended thoracic aortic disease in 224 patients (mean age, 72.1 ± 10.9 years) from September 1997 to December 2011. The patients included those with acute type A aortic dissection (n = 103), acute type B aortic dissection (n = 30), chronic type B aortic dissection (n = 11) and thoracic atherosclerotic aneurysm (n = 80). Cerebrospinal fluid drainage (CSFD) was preoperatively performed for 18 elective cases with a high risk of spinal cord ischaemia from January 2003.
  
  
  RESULTS
  Postoperative SCI was present in 8 (3.5%), including complete paraplegia in 3, patients and transient or permanent paraparesis in 5 patients. CSFD was not a significant independent risk factor (P = 0.93) for SCI. Univariate logistic regression analysis identified pathology (P = 0.001), diabetes (P = 0.001), previous aortic operation (P = 0.003), atherosclerotic aorta (P = 0.003), distal position of the stent graft below the ninth thoracic vertebral level (Th9; P = 0.001) and low blood pressure after the operation (P = 0.009) as significant independent risk factors for SCI. Stepwise logistic regression analysis identified the distal position of the stent graft below Th9 (P = 0.003; odds ratio [OR], 15.167; 95% confidence interval [95% CI], 2.568-89.578), mean pressure <70 mmHg (P = 0.008; OR, 11.470; 95% CI, 1.920-68.546) and diabetes (P = 0.009; OR, 9.621; 95% CI, 1.779-52.032) as significant independent risk factors for SCI.
  
  
  CONCLUSIONS
  There were multiple factors predicting the risk of SCI after the FET technique. Paraplegia may be prevented by avoiding deep insertion of the stent graft and by keeping blood pressure elevated after the operation.
authors.affiliation: Department of Surgery, Hiroshima University Hospital, Hiroshima, Japan kjr1020cvs@yahoo.co.jp.
authors.forename: Keijiro
authors.initials: K
authors.lastname: Katayama
authors.affiliation: Department of Surgery, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Naomichi
authors.initials: N
authors.lastname: Uchida
authors.affiliation: Department of Cardiovascular Surgery, Hiroshima City Asa General Hospital, Hiroshima, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Katayama
authors.affiliation: Department of Surgery, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Takahashi
authors.affiliation: Department of Surgery, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Taiichi
authors.initials: T
authors.lastname: Takasaki
authors.affiliation: Department of Surgery, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kurosaki
authors.affiliation: Department of Surgery, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Imai
authors.affiliation: Department of Surgery, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Taijiro
authors.initials: T
authors.lastname: Sueda
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017545:Aortic Aneurysm, Thoracic / Q000601:surgery*; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D013119:Spinal Cord Injuries / Q000453:epidemiology* / Q000209:etiology*
keywords: Extended thoracic aortic disease; Frozen elephant trunk; Spinal cord injury