title: A new classification of complications in neurosurgery.
abstract: OBJECTIVE
  To define and grade neurosurgical and spinal postoperative complications based on their need for treatment.
  
  
  METHODS
  Complications were defined as any deviation from the normal postoperative course occurring within 30 days of surgery. A four-grade scale was proposed based on the therapy used to treat the complications: grade I, any non-life-threatening complications treated without invasive procedures; grade II, complications requiring invasive management such as surgical, endoscopic, and endovascular procedures; grade III, life-threatening adverse events requiring treatment in an intensive care unit (ICU); and grade IV, deaths as a result of complications. Each grade was classified as a surgical or medical complication. An observational test of this system was conducted between January 2008 and December 2009 in a cohort of 1190 patients at the Hospital Italiano de Buenos Aires.
  
  
  RESULTS
  Of 167 complications, 129 (10.84%) were classified as surgical, and 38 (3.19%) were classified as medical complications. Grade I (mild) complications accounted for 31.73%, grade II (moderate) complications accounted for 25.74%, and grade III (severe) complications accounted for 34.13%. The overall mortality rate was 1.17%; 0.84% of deaths were directly related to surgical procedures.
  
  
  CONCLUSIONS
  The authors present a simple, practical, and easy to reproduce way to report negative outcomes based on the therapy administered to treat a complication. The main advantages of this classification are the ability to compare surgical results among different centers and times, the ability to compare medical and surgical complications, and the ability to perform future meta-analyses.
authors.affiliation: Department of Neurosurgery of the Hospital Italiano de Buenos Aires, Argentina. fedelandriel@gmail.com
authors.forename: Federico Alfonso
authors.initials: FA
authors.lastname: Landriel Ibañez
authors.forename: Santiago
authors.initials: S
authors.lastname: Hem
authors.forename: Pablo
authors.initials: P
authors.lastname: Ajler
authors.forename: Eduardo
authors.initials: E
authors.lastname: Vecchi
authors.forename: Carlos
authors.initials: C
authors.lastname: Ciraolo
authors.forename: Matteo
authors.initials: M
authors.lastname: Baccanelli
authors.forename: Ruben
authors.initials: R
authors.lastname: Tramontano
authors.forename: Fernando
authors.initials: F
authors.lastname: Knezevich
authors.forename: Antonio
authors.initials: A
authors.lastname: Carrizo
mesh_terms: D000758:Anesthesia; D001118:Argentina / Q000453:epidemiology; D001921:Brain / Q000601:surgery; D015331:Cohort Studies; D003422:Critical Care; D006801:Humans; D009493:Neurosurgery / Q000145:classification*; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D011183:Postoperative Complications / Q000145:classification* / Q000401:mortality / Q000628:therapy; D012086:Reoperation; D013116:Spinal Cord / Q000601:surgery; D013131:Spine / Q000601:surgery; D016896:Treatment Outcome