title: New prototype of femoral arterial SmartCannula with anterograde and retrograde flow.
abstract: OBJECTIVE
  Femoral artery cannulation is routinely used in circulatory support scenarios for cardiorespiratory support in patients with acute cardiac and/or pulmonary decompensation. During prolonged perfusion, this may cause acute ischemia of the leg and, in the worst case, even amputation. The aim of this experimental study was to test a newly designed arterial cannula allowing proximal and distal blood flow.
  
  
  METHODS
  Veno-arterial cardiopulmonary bypass was established in three calves (67.6 ± 5.1 kg). The venous line was secured by cannulation of the external jugular vein. The arterial line of each animal was secured by cannulation of iliac arteries on both legs. On one side, we used a modified SmartCannula (SmartCannula 18Fr 130 mm) and, on the other side, a standard rectilinear BioMedicus cannula system was used, 19 Fr for retrograde and an 8 Fr BioMedicus shunt for anterograde flow toward the leg. An ultrasonic flow probe was used to quantify the perfusion of the distal leg.
  
  
  RESULTS
  At 0.5, 1.0, 1.5, and 2.0 l/min, the anterograde leg blood flow increased steadily for each cannula, but remained higher in the self-expanding cannula. That is, the 8 F rectilinear cannula achieved a blood flow of 0.02 ± 0.01, 0.1 ± 0.04, 0.22 ± 0.09, and 0.21 ± 0.02 l/min, respectively, and the 18 F self-expanding cannula achieved 0.06 ± 0.02, 0.15 ± 0.03, 0.24 ± 0.07 and 0.36 ± 0.04 l/min.
  
  
  CONCLUSIONS
  The modified self-expanding cannula exhibited superior distal arterial flow compared to the routinely used rectilinear shunt system. This has a potential to reduce ischemic events of the inferior extremity in prolonged perfusion.
authors.affiliation: Department of Cardiovascular Surgery, Centre Hospitalier Universitaire Vaudois, Rue du Bugnon 46, Lausanne, Switzerland. denis.berdajs@chuv.ch
authors.forename: Denis
authors.initials: D
authors.lastname: Berdajs
authors.forename: Enrico
authors.initials: E
authors.lastname: Ferrari
authors.forename: Alexandre
authors.initials: A
authors.lastname: Michalis
authors.forename: Marco
authors.initials: M
authors.lastname: Burki
authors.forename: Christian W
authors.initials: CW
authors.lastname: Pieterse
authors.forename: Judith
authors.initials: J
authors.lastname: Horisberger
authors.forename: Ludwig K
authors.initials: LK
authors.lastname: von Segesser
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D002315:Cardiopulmonary Bypass / Q000295:instrumentation* / Q000379:methods*; D002404:Catheterization / Q000295:instrumentation* / Q000379:methods; D057785:Catheters; D002417:Cattle; D005263:Femoral Artery; D007601:Jugular Veins