title: Postoperative Nonpathologic Fever After Spinal Surgery: Incidence and Risk Factor Analysis.
abstract: BACKGROUND
  Although there are many postoperative febrile causes, surgical-site infection has always been considered as one of the major causes, but it should be excluded; we encountered many patients who showed delayed postoperative fever that was not related to wound infection after spinal surgery. We aimed to determine the incidence of delayed postoperative fever and its characteristics after spinal surgery, and to analyze the causal factors.
  
  
  METHODS
  A total of 250 patients who underwent any type of spinal surgery were analyzed. We determined febrile patients as those who did not show any fever until postoperative day 3, and those who showed a fever with an ear temperature of greater than 37.8°C at 4 days after surgery. We collected patient data including age, sex, coexistence of diabetes mellitus or hypertension, smoking history, location of surgical lesion (e.g., cervical, thoracic, lumbar spine), type of surgery, surgical approach, diagnosis, surgical level, presence of revision surgery, operative time, duration of administration of prophylactic antibiotics, and the presence of transfusion during the perioperative period, with a chart review.
  
  
  RESULTS
  There were 33 febrile patients and 217 afebrile patients. Multivariate logistic regression showed that surgical approach (i.e., posterior approach with anterior body removal and mesh graft insertion), trauma and tumor surgery compared with degenerative disease, and long duration of surgery were statistically significant risk factors for postoperative nonpathologic fever.
  
  
  CONCLUSIONS
  We suggest that most spinal surgeons should be aware that postoperative fever can be common without a wound infection, despite its appearance during the late acute or subacute period.
authors.affiliation: Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Junghan
authors.initials: J
authors.lastname: Seo
authors.affiliation: Department of Neurological Surgery, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung-si, Gangwon-do, Korea. Electronic address: grandblue@gnah.co.kr.
authors.forename: Jin Hoon
authors.initials: JH
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung-si, Gangwon-do, Korea.
authors.forename: Eun Hee
authors.initials: EH
authors.lastname: Song
authors.affiliation: Department of Neurological Surgery, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Young-Seok
authors.initials: YS
authors.lastname: Lee
authors.affiliation: Department of Emergency Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung-si, Gangwon-do, Korea.
authors.forename: Sang Ku
authors.initials: SK
authors.lastname: Jung
authors.affiliation: Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sang Ryong
authors.initials: SR
authors.lastname: Jeon
authors.affiliation: Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Seung Chul
authors.initials: SC
authors.lastname: Rhim
authors.affiliation: Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sung Woo
authors.initials: SW
authors.lastname: Roh
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D019072:Antibiotic Prophylaxis; D001803:Blood Transfusion / Q000706:statistics & numerical data; D002574:Cervical Vertebrae / Q000601:surgery; D015897:Comorbidity; D019299:Decompression, Surgical; D005260:Female; D005334:Fever / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D055959:Intervertebral Disc Degeneration / Q000453:epidemiology / Q000601:surgery*; D016015:Logistic Models; D008159:Lumbar Vertebrae / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D044583:Neuroendoscopy; D019635:Neurosurgical Procedures; D016017:Odds Ratio; D061646:Operative Time; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013122:Spinal Diseases / Q000453:epidemiology / Q000601:surgery; D013123:Spinal Fusion; D013124:Spinal Injuries / Q000453:epidemiology / Q000601:surgery*; D013125:Spinal Neoplasms / Q000453:epidemiology / Q000601:surgery*; D013526:Surgical Mesh; D013530:Surgical Wound Infection / Q000453:epidemiology; D013904:Thoracic Vertebrae / Q000601:surgery
keywords: Fever; Long-duration surgery; Postoperative fever; Spinal surgery; Subacute period; Tissue trauma; Trauma