title: Inferior vena cava filter migration during the prone position for spinal surgery: a case report.
abstract: OBJECTIVE
  Inferior vena cava (IVC) filters have been used as an alternative therapy for patients with a contraindication to anticoagulation. We present a case of an IVC filter migration to the right ventricle occurring while a trauma patient was undergoing spinal surgery in the prone position. The patient provided written consent to describe this case.
  
  
  METHODS
  A 54-yr-old multiple trauma male patient with an unstable fracture of the T6 vertebra and a stable fracture of the T10 vertebra developed a pulmonary embolism secondary to a left common femoral deep vein thrombosis. An IVC filter was placed so that an intravenous unfractionated heparin infusion could be stopped two days before scheduled spinal surgery. Intraoperatively, the patient was placed in the prone position on conventional convex support pads. At the end of the procedure, he developed ventricular trigeminy which lasted three minutes. During the next 48 hr, the patient developed a fever of 39°C. An echocardiogram was performed to rule out endocarditis, and results showed that the IVC filter had migrated into the right ventricle. After a failed attempt at percutaneous removal of the filter in the catheterization laboratory, the patient was transferred to the operating room and the IVC filter was extracted through a midline sternotomy under cardiopulmonary bypass.
  
  
  CONCLUSIONS
  The prone position during surgery can induce anatomic and hemodynamic changes in the IVC. This may contribute to the migration of IVC filters--especially flexible retrievable filters. Careful handling and positioning of patients with IVC filters is recommended to avoid a sudden increase in IVC pressure that may predispose to IVC filter migration.
authors.affiliation: Department of Anesthesiology and Intensive Care, Saint Joseph University Medical School Hotel Dieu de France Hospital, Boulevard Alfred Naccache, P.O. BOX 166830, Beirut, Lebanon, vivchalhoub@yahoo.com.
authors.forename: Viviane
authors.initials: V
authors.lastname: Chalhoub
authors.forename: Joanna
authors.initials: J
authors.lastname: Tohmé
authors.forename: Freda
authors.initials: F
authors.lastname: Richa
authors.forename: Christine
authors.initials: C
authors.lastname: Dagher
authors.forename: Patricia
authors.initials: P
authors.lastname: Yazbeck
mesh_terms: D005548:Foreign-Body Migration / Q000150:complications*; D006493:Heparin / Q000008:administration & dosage; D006801:Humans; D008297:Male; D008875:Middle Aged; D016684:Prone Position; D011655:Pulmonary Embolism / Q000517:prevention & control*; D016103:Spinal Fractures / Q000601:surgery*; D016306:Vena Cava Filters / Q000009:adverse effects*; D014682:Vena Cava, Inferior; D018879:Ventricular Premature Complexes / Q000209:etiology
chemical_list: D006493:Heparin