Hemodynamic stability during arteriovenous carbon dioxide removal for adult respiratory distress syndrome: A prospective randomized outcomes study inadult sheep

To evaluate the ability of arteriovenous carbon dioxide removal (AVCO(2)R) to maintain hemodynamic stability during treatment of adult respiratory dis tress syndrome (ARDS), we used our smoke/burn, LD40 sheep model of ARDS. Wi th onset of ARDS (PaO2/FiO(2) < 200) animals were randomized to AVCO(2)R (n = 20) or SHAM (n = 8). With AVCO(2)R, the carotid artery (10-14 F) and jug ular vein (14-16 F) were cannulated; SHAM received identical management, sp aring the vessels. AVCO(2)R maintained stable hemodynamics compared to SHAM at 48 hours; heart rate (114.8 +/- 6.1 vs. 110.1 +/- 11.0 beats/min.), mea n arterial pressure (112 +/- 5.1 vs. 107.0 +/- 8.5 mm Hg), cardiac output ( 7.4 +/- 0.5 vs. 7.5 +/- 0.9 L/min.), pulmonary arterial pressure (26 +/- 2. 4 vs.21 +/- 1.3 mm Hg), pulmonary arterial wedge pressure (14.1 +/- 1.8 vs. 14.0 +/- 1.2 mm Hg), and central venous pressure (7 +/- 1.6 vs. 8 +/- 0.9 mm Hg). At 48 hours, AVCO(2)R allowed significant reductions (p <0.05) in m inute ventilation (13.6 +/- 2.5 to 7.6 +/- 0.8 L/min); tidal volume (TV) (3 89.4 +/- 24.1 to 295.0 +/- 10.1 ml); peak inspiratory pressure (PIP) (25.4 +/- 9.2 to 18.8 +/- 2.5 cm H2O); RR (27.5 +/- 0.7 to 21.6 +/- 1.8 breaths/m in); and FiO(2) (0.96 +/- 0.00 to 0.48 +/- 0.2) while normocapnia was maint ained. AVCO(2)R is an effective method of CO2 removal during severe respira tory failure that is hemodynamically well tolerated.