Ex vivo evaluation of a new neonatal/infant oxygenator: comparison of the Terumo CAPIOX Baby RX with Dideco Lilliput 1 and Polystan Safe Micro in the piglet model

OBJECTIVE: A newly developed neonatal and infant oxygenator with a nonheparin biocompatible polymer coating, low priming volume (43 mL), high oxygen transfer, wide operating range (<1.5 L/min) and low pressure drop represents a promising solution for cardiac surgery in neonates and infants. We compared the new CAPIOX Baby RX, Terumo (BRX) with two commonly used neonatal oxygenators: Dideco Lilliput 1 (DL1) and Polystan Safe Micro (PSM) in a piglet model. METHODS: Fifteen piglets (5.6 +/- 1.3kg) were placed on standardized cardiopulmonary bypass (CPB) for 6 hours using one of the three oxygenators (n = 5 in each group). After 120 min, the system was cooled to 25 degrees C for 60 min and then returned to normothermia. Arterial and venous blood gas data and temperature were recorded continuously by a CDI500 System (Terumo). Pressure drop, FiO2 and gas flow were recorded. Blood samples were taken before CBP, after 10 min, before and after cooling, and at the end. Total blood counts, thrombin-antithrombin complex and plasma-free haemoglobin (PfHb) were measured. RESULTS: All oxygenators showed acceptable performance for the duration of CPB. The BRX had lower mean gas flow (0.33 +/- 0.05 L/min) and FiO2 (0.43 +/- 0.02%) throughout CPB than the DL1 (1.14 +/- 0.25 L/min, p = 0.006 and 0.60 +/- 0.02%, p = 0.009, respectively) or the PSM (1.47 +/- 0.87 L/min and 0.54 +/- 0.08%, p = ns). Pressure drop in the BRX group ranged from 12 to 22 mmHg. This was significantly lower than in the DL1 group (39-65 mmHg, p = 0.005). In the PSM group, values ranged between 24 and 33 mmHg (p = ns). The increase in PfHb at six hours was significantly lower in the BRX (11.3 +/- 4.2 ng/dL) versus the DL1 (42.2 +/- 6.1 ng/dL, p = 0.004) and the PSM (56.7 +/- 15.5 ng/dL, p = 0.045). CONCLUSIONS: The BRX is as safe as the DL1 and the PSM, with superior performance in pressure drop, efficient blood gas management and lower haemolysis. The BRX exhibited the lowest prime, hold-up volume and breakthrough time.