title: Influence of blood coagulability after spinal surgeries.
abstract: OBJECTIVE
  To verify whether spinal surgery causes relevant changes in the blood clotting process and define which factors have the greatest influence on changes found.
  
  
  METHODS
  This is a not randomized, cross-sectional study, Forty seven patients were evaluated between August 2011 and February 2013, whose clinical, surgical, laboratory and image daata were collected. The data obtained were crossed with the epidemiological data of each patient in a moment prior to and another after surgery searching which variables have been directly influenced.
  
  
  RESULTS
  Our analysis showed that the most important changes occurred in patients with BMI classified, according to the World Health Organization (WHO) as out of healthy range. Other smaller correlations were also found. Another important consideration was the tendency to observe hypercoagulability in smoker patients, a fact that is not influenced by spinal procedures.
  
  
  CONCLUSIONS
  We concluded that spinal surgeries cause few relevant changes in the blood clotting process and that among the factors studied, BMI (when out of the healthy range, according to the WHO classification) showed closer relationship with changes in laboratory coagulation tests. Level of Evidence III, Cross-Sectional Study.
authors.affiliation: Hospital Santa Marcelina, Department of Orthopedics and Traumatology, São Paulo, SP, Brazil, Department of Orthopedics and Traumatology, Hospital Santa Marcelina, São Paulo, SP, Brazil.
authors.forename: Marcelo Hide
authors.initials: MH
authors.lastname: Matsumoto
authors.affiliation: Hospital Santa Marcelina, Department of Orthopedics and Traumatology, São Paulo, SP, Brazil, Department of Orthopedics and Traumatology, Hospital Santa Marcelina, São Paulo, SP, Brazil.
authors.forename: Luiz Claudio Lacerda
authors.initials: LC
authors.lastname: Rodrigues
authors.affiliation: Hospital Santa Marcelina, Department of Orthopedics and Traumatology, São Paulo, SP, Brazil, Department of Orthopedics and Traumatology, Hospital Santa Marcelina, São Paulo, SP, Brazil.
authors.forename: Luiz Gustavo da Silva
authors.initials: LG
authors.lastname: Batalini
authors.affiliation: Hospital Santa Marcelina, Department of Orthopedics and Traumatology, São Paulo, SP, Brazil, Department of Orthopedics and Traumatology, Hospital Santa Marcelina, São Paulo, SP, Brazil.
authors.forename: Thales Arcanjo
authors.initials: TA
authors.lastname: Fonteles
authors.affiliation: Hospital Santa Marcelina, Department of Orthopedics and Traumatology, São Paulo, SP, Brazil, Department of Orthopedics and Traumatology, Hospital Santa Marcelina, São Paulo, SP, Brazil.
authors.forename: Adalberto
authors.initials: A
authors.lastname: Bortoletto
keywords: Blood coagulation disorders; Orthopedics; Spine; Thrombosis