title: Prophylaxis for deep venous thrombosis in craniotomy patients: a decision analysis.
abstract: OBJECTIVE
  We sought to determine the most efficient perioperative prophylactic strategy for deep venous thrombosis (DVT) in craniotomy patients by use of a decision analysis model.
  
  
  METHODS
  We conducted a structured review of the relevant literature and compiled the reported incidences of DVT, pulmonary embolism, and postoperative intracranial hemorrhage (ICH) in craniotomy patients. We also obtained from the literature estimates of the likelihood and the impact of various outcomes of these complications. Data from 810 craniotomies performed at our own institution were also examined. The decision analytic model was then used to compare the effectiveness of pneumatic compression boots with pneumatic compression boots combined with either unfractionated or low-molecular-weight heparin. The model dealt with variability by using both sensitivity analysis and Monte Carlo simulation.
  
  
  RESULTS
  As expected, the addition of heparin lowered the incidence of both DVT and pulmonary embolism, but at the cost of increasing ICH. Because the deleterious effects of ICH were so much greater than the benefits from heparinization, overall outcomes were best with mechanical prophylaxis alone. This was especially true for low-molecular-weight heparin, which is associated with a relatively high risk of ICH. Our own institutional data support the findings in the literature. Although the differences are modest, they reach statistical significance in the case of low-molecular-weight heparin.
  
  
  CONCLUSIONS
  Using decision analytic modeling, we have shown that mechanical prophylaxis yields outcomes in craniotomy patients superior to those of either unfractionated or low-molecular-weight heparin.
authors.affiliation: Department of Neurosurgery, The Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA. Shabbardanish@hotmail.com
authors.forename: Shabbar F
authors.initials: SF
authors.lastname: Danish
authors.forename: Mark G
authors.initials: MG
authors.lastname: Burnett
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Ong
authors.forename: Seema S
authors.initials: SS
authors.lastname: Sonnad
authors.forename: Eileen
authors.initials: E
authors.lastname: Maloney-Wilensky
authors.forename: Sherman C
authors.initials: SC
authors.lastname: Stein
mesh_terms: D000925:Anticoagulants / Q000008:administration & dosage*; D003399:Craniotomy / Q000009:adverse effects* / Q000379:methods; D003661:Decision Support Techniques; D006801:Humans; D020300:Intracranial Hemorrhages / Q000601:surgery; D020246:Venous Thrombosis / Q000209:etiology* / Q000517:prevention & control*
chemical_list: D000925:Anticoagulants