title: Improved oxygenation with reduced recirculation during venovenous ECMO: comparison of two catheters.
abstract: OBJECTIVE
  To determine whether the new double-lumen catheter made by OriGen Biomedical (Austin, TX) for venovenous (VV) extracorporeal membrane oxygenation (ECMO) would reduce recirculation and improve oxygenation during VV ECMO when compared with the Kendall double-lumen catheter (Kendall Healthcare Products, Mansfield, MA).
  
  
  METHODS
  Prospective intervention study.
  
  
  METHODS
  The animal research laboratory at Children's National Medical Center, Washington, DC.
  
  
  METHODS
  Nine newborn lambs one to seven days old and weighing 4.4 +/- 0.8 kg.
  
  
  METHODS
  Animals were anesthetized, intubated, and ventilated. The ductus arteriosus was ligated. Femoral arterial and venous, cephalic jugular vein, and pulmonary artery catheters were placed. After systemic heparinization, the catheter to be tested, an OriGen catheter, was placed in the right internal jugular vein and advanced into the right atrium. The animal was placed on ECMO and stabilized, with the ventilator settings decreased to a peak inspiratory pressure of 15-20 cmH2O, peak end-expiratory pressure of 5 cmH2O, rate of 15-25 breaths/min, and a fractional inspired oxygen concentration of 0.21-0.30. ECMO flows were increased in 100-ml increments from 200 to 600 ml/min with measurements taken 15 min after each change. The OriGen catheter was removed, the Kendall catheter was placed, and the studies were repeated.
  
  
  RESULTS
  Heart rate, mean blood pressure, PaO2, jugular cerebral oxygen saturation, pulmonary artery oxygen saturation, pump venous oxygen saturation, and postmembrane circuit pressures were measured at each study period. The OriGen catheter improved oxygenation, with higher systemic PaO2, higher pulmonary artery and cerebral oxygen saturations, and lower pump venous oxygen saturations (indicating less recirculation). With the OriGen catheter, PaO2 levels ranged from 69 +/- 18 mmHg [9.2 +/- 2.4 kPa] to 114 +/- 45 mmHg [15.2 +/- 6.0 kPa], compared range from 61 +/- 15 mmHg [8.1 +/- 2.0 kPa] to 87 +/- 34 mmHg [11.5+/-4.5 kPa] for the Kendall catheter. These findings indicate that, at all flow rates studied, less recirculation occurred with the OriGen catheter than with the Kendall catheter. The postmembrane pressures were significantly lower for the OriGen catheter at any given flow (from 30 +/- 5 to 122 +/- 18 mmHg) when compared with the Kendall catheter (from 77+/- 16 to 330+/-78 mmHg).
  
  
  CONCLUSIONS
  These findings indicate that the OriGen catheter resulted in a reduction of recirculation, thereby resulting in an improvement in oxygenation while on VV ECMO. The lower postmembrane pressure potentially could reduce the risk of ECMO circuit complications such as tubing rupture, bleeding complications, as well as hemolysis. This new catheter makes VV ECMO more effective and represents a design that could be used for neonatal and/or pediatric ECMO.
authors.affiliation: Department of Neonatology, Children's National Medical Center, Washington, District of Columbia 20010, USA.
authors.forename: Khodayar
authors.initials: K
authors.lastname: Rais-Bahrami
authors.forename: Dawn M
authors.initials: DM
authors.lastname: Walton
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Sell
authors.forename: Oswaldo
authors.initials: O
authors.lastname: Rivera
authors.forename: Gerald T
authors.initials: GT
authors.lastname: Mikesell
authors.forename: Billie L
authors.initials: BL
authors.lastname: Short
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002404:Catheterization; D002536:Cerebral Arteries; D004867:Equipment Design; D015199:Extracorporeal Membrane Oxygenation / Q000295:instrumentation* / Q000379:methods; D010100:Oxygen / Q000097:blood*; D010313:Partial Pressure; D011651:Pulmonary Artery; D012756:Sheep
chemical_list: D010100:Oxygen