DNase I Treatment for Cardiac Surgery

This study was approved by the local authority LANUV (Landesamt für Natur, Umwelt und Verbraucherschutz NRW; AZ84-02.04.2014.A103) and carried out in accordance with German and European guidelines of laboratory animal care. 24 male Wistar rats weighing between 510 and 525 g (Janvier Breeding Center, France) were randomly assigned to three experimental groups: one control group undergoing CPB with DHCA (group 1), one group undergoing CPB with DHCA that received an i.v. bolus of DNase I (Pulmozyme®, Roche, 5 mg/kg body weight) before CPB (group 2), and one group undergoing CPB with DHCA that received DNase I before CPB and a second bolus after rewarming/before reperfusion, respectively (group 3). This DNase I dose was previously found to effectively degrade plasma cfDNA/NETs^{18 (link),36 (link)}. Two animals with low haemoglobin concentration during the procedure (Hb < 5.0 mg/dL) caused by a diffuse bleeding at the insertion site of the arterial cannula developed a catecholamine-refractory hypotension and were subsequently excluded from the study. The study was conducted with 7 animals in groups 1 and 2 respectively, and 8 animals in group 3.