LONG-TERM CARDIOPULMONARY BYPASS WITHOUT SYSTEMIC HEPARINIZATION

Cardiopulmonary bypass over 24 hours using heparin surface coated equipment, without systemic heparinization was analyzed in comparison to standard equipment with systemic heparinization in 8 open-chest canine experiments (37 ± 7 kg). Mean duration of perfusion was 21 ± 2 hours for the group perfused without versus 21 ± 6 hours with systemic heparinization. The group without systemic heparinization could be perfused for 13 ± 1 hours without transfusion of blood components whereas the pumpsucker was necessary during the whole procedure with systemic heparinization. Hematocrit dropped with systemic heparinization from 40 ± 7% to 18 ± 5% at 12 h versus a decrease from 38 ± 4% to 15 ± 1% without (with versus without: ns). Free plasma hemoglobin increased with systemic heparinization from 0.1 ± 0.0 g/l to 1.4 ± 1.2 g/l at 12 h compared with an increase 0.1 ± 0.0 g/l to 0.3 ± 0.1 g/l without (with versus without: p < 0.05). Platelet levels dropped with systemic heparinization from 100 ± 36% to 41 ± 17% at twelve hours versus from 100 ± 29% to 82 ± 14 without (with versus without: p < 0.05). Mean aortic pressure dropped with systemic heparinization from 73 ± 12 mmHg to 53 ± 4 mmHg at 22 hours whereas it remained at the same level without (83 ± 6 mmHg). Improved hemostasis during long term open-chest cardiopulmonary bypass without systemic heparinization resulted in superior hemodynamics.