Clinical and biomaterial evaluation of a new condensed dual-function extracorporeal circuit in reoperation for coronary artery bypass surgery

Abstract

Purpose: This prospective, randomized study compared the clinical performance of three types of circuits: a newly introduced, fully-coated, interchangeable open-closed circuit with a dual configuration (hard shell with a bypass shunt), reduced length, and reduced prime of less than 800 cc (CondEC); a completely coated circuit (EC); and a similar uncoated, open circuit with standard length and prime (CONT). Methods: 75 patients undergoing reoperation for coronary revascularization were randomly allocated into three groups (N=25): Group 1: CondEC with shortened tubing, components and an open-closed configuration of low priming volume with a centrifugal pump and a shunt which bypassed the reservoir for closed configuration; Group 2: EC with a roller pump and hard-shell reservoir; Group 3: CONT. Blood samples for CBC, inflammatory mediators [Interleukin-2 (IL-2), Complement-3a (C3a)] and flow cytometry (CD11b/CD18) were collected after induction (T1) and heparin administration (T2), 15 min after cardiopulmonary bypass (CPB) (T3), before cessation of CPB (T4), 15 min after reversal (T5), and the first postoperative day (T6). Results: Leukocyte counts demonstrated significant increases at T4, T5 in CONT but remained stable in EC and CondEC (p<0.05). Platelets were preserved better at T4, T5 in both EC and CondEC study groups (p<0.05). IL-2 and C3a levels were significantly lower at T3, T4, T5 in CondEC and T4, T5 in EC (p<0.05). Blood protein adsorption analysis demonstrated increased amount of microalbumin on CONT fibers (p<0.05). Conclusions: The CondEC is a flexible, dual-function, open/closed configuration system that was easy to use, safe and achieved better biocompatibility when compared to coated and uncoated conventional circuits. (Int J Artif Organs 2009; 32: 802-10)