title: Temporary caval stenting improves venous drainage during cardiopulmonary bypass.
abstract: OBJECTIVE
  Assess the benefit of temporary caval stenting for remote venous drainage during cardiopulmonary bypass (CPB).
  
  
  METHODS
  Temporary caval stenting was realized in bovine experiments (65+/-6 kg) by the means of self-expanding (18F for insertion, 36F in situ) venous cannulas (Smartcanula LLC, Lausanne, Switzerland) with various lengths: 43 cm, 53 cm, 63 cm vs. a standard 28F wire armed cannula in trans-jugular fashion. Maximal blood flows were assessed for 20, 25 and 30 mmHg of driving pressure with a motorized table height adjustment system. In addition, the inferior caval diameters (just above its bifurcation) were measured in real time with intra-vascular ultrasound (IVUS).
  
  
  RESULTS
  Venous drainage (flow in l/min) at 20 mmHg, 25 mmHg, and 30 mmHg drainage load was 3.5+/-0.5, 3.7+/-0.7 and 4.0+/-0.6 for the 28F standard vs. 4.1+/-0.7, 4.0+/-1.3 and 3.9+/-1.1 for the 36F smart 43 cm, vs. 5.0+/-0.7, 5.3+/-1.3 and 5.4+/-1.4 for the 36F smart 53 cm, vs. 5.2+/-0.5*, 5.6+/-1.1* and 5.8+/-1.0* for the 36F smart 63 cm. The inferior vena caval diameters at 30 mmHg were 13.5+/-4.8 mm for 28F standard, 11.1+/-3.6 for 36F smart 43 cm, 11.3+/-3.2 for 36F 53 cm, and 17.0+/-0.1* for 36F 63 cm (*P<0.05 for 28F standard vs. 36F smart 63 cm long)
  
  
  CONCLUSIONS
  The 43 cm self-expanding 36F smartcanula outperforms the 28F standard wire armed cannula at low drainage pressures and without augmentation. Temporary caval stenting with long self-expanding venous cannulas provides even better drainage (+51%).
authors.affiliation: Department of Cardio-Vascular Surgery, Centre Hospitalier Universitaire Vaudois, CHUV, Lausanne, Lausanne, Switzerland. Ludwig.von-segesser@chuv.ch
authors.forename: Ludwig K
authors.initials: LK
authors.lastname: von Segesser
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Siniscalchi
authors.forename: Kwang
authors.initials: K
authors.lastname: Kang
authors.forename: Olaf
authors.initials: O
authors.lastname: Maunz
authors.forename: Judith
authors.initials: J
authors.lastname: Horisberger
authors.forename: Enrico
authors.initials: E
authors.lastname: Ferrari
authors.forename: Dominique
authors.initials: D
authors.lastname: Delay
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Tozzi
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D002315:Cardiopulmonary Bypass; D002405:Catheterization, Central Venous / Q000295:instrumentation*; D002417:Cattle; D002496:Central Venous Pressure; D004867:Equipment Design; D006112:Gravitation; D011474:Prosthesis Design; D012039:Regional Blood Flow; D015607:Stents; D018084:Ultrasonography, Interventional; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging / Q000503:physiopathology*