title: The influence of a one-step reamer-irrigator-aspirator technique on the intramedullary pressure in the pig femur.
abstract: BACKGROUND
  Increased intramedullary pressure in the femoral cavity causes intravasation of bone marrow content to the circulation which may lead to occlusion of pulmonary vessels and cardiorespiratory dysfunction. A one-step reamer-irrigator-aspirator (RIA) technique has been developed to reduce the intramedullary pressure (IMP) during the reaming procedure. This study was design to compare IMP with a standard reaming technique with IMP during reaming with the RIA system with a hypothesis that the RIA system would involve lower pressures.
  
  
  METHODS
  In a randomised study in 19 Norwegian landrace pigs reamed intramedullary nailing was performed with two different reamer devices. Nine animals were operated with a traditional reamer and 10 animals with RIA. One animal in the RIA group was excluded due to a perioperative femoral fracture, and three animals in the traditional group were excluded due to a perforation of the distal medial femoral cortex. The intramedullary pressure was registrated with a transducer-tipped pressure monitoring catheter during reaming.
  
  
  RESULTS
  There was a significantly higher intramedullary pressure (P<0.05) during reaming in the traditional reamer group (mean 188+/-38 mmHg) than in the RIA group (mean 33+/-8 mmHg). Intramedullary pressures recorded before surgery, at the opening of the femoral cavity with an awl, by insertion of a guide wire, at insertion of the intramedullary nail, and 10 min after nail insertion showed no significant differences between the groups.
  
  
  CONCLUSIONS
  The use of a one-step reamer-irrigator-aspirator technique in the pig femur induced less intramedullary pressure increase than the use of a traditional reamer.
authors.affiliation: Orthopedic Center, Ullevaal University Hospital, Kirkeveien 166, 0407 Oslo, Norway. i.e.ellingsen@medisin.uio.no
authors.forename: Elisabeth Ellingsen
authors.initials: EE
authors.lastname: Husebye
authors.forename: Torstein
authors.initials: T
authors.lastname: Lyberg
authors.forename: Jan Erik
authors.initials: JE
authors.lastname: Madsen
authors.forename: Morten
authors.initials: M
authors.lastname: Eriksen
authors.forename: Olav
authors.initials: O
authors.lastname: Røise
mesh_terms: D000818:Animals; D001853:Bone Marrow; D004195:Disease Models, Animal; D004620:Embolism, Fat / Q000517:prevention & control*; D004867:Equipment Design; D005269:Femur / Q000503:physiopathology / Q000601:surgery*; D005594:Fracture Fixation, Intramedullary / Q000295:instrumentation* / Q000379:methods; D011312:Pressure; D011897:Random Allocation; D013396:Suction; D013552:Swine; D007507:Therapeutic Irrigation