Determination and comparison of heat exchange efficiency of four commercially available blood cardioplegia sets

Abstract

An in vitro comparison of the heat exchange properties of the Electromedics D1081A, Sarns MP-4 'Conducer Coil' 165720, Bentley HE-1 00 and the Shiley BCD Plus 4:1 blood cardioplegia sets was performed. The efficiency was calculated for each heat exchanger and post-heat exchange blood path temperatures were compared. The calculated efficiency for each heat exchanger is as follows: Electromedics D1081A at 18 I/minute coil water flow (0.95); Sarns MP-4 165720 at 9 I/minute coil water flow (0.93); Bentley HE-100 at 10 I/minute coil water flow (0.91); Shiley BCD Plus at 15 I/minute coil water flow (0.90). Blood path, precoil temperatures for each unit were compared statistically with no differences found ( p > 0.05). Blood side, postcoil temperatures were then compared. The average postcoil blood path temperature of the Electromedics D1081A was 1.6° ± 0.1 °C, of the Sarns MP-4 165720 it was 2.1 ± 0.1°C, of the Bentley HE-100 it was 2.7° ± 0.3°C, and the Shiley BCD Plus 3.0° ± 0.4°C. The results of this experiment indicate that the average postcoil temperature of the Electromedics D1081 A was lower than the Sarns MP-4 165720 ( p < 0.05) which was lower than that of the Bentley HE-100 ( p < 0.05) and Shiley BCD Plus ( p < 0.05). No statistical difference was found between the average postcoil temperature of the Bentley HE-1 00 and the Shiley BDC Plus.