The Journal of ExtraCorporeal Technology No 58-1 | Page 32

26 T. Rath et al.: J Extra Corpor Technol 2026, 58, 19 – 31

Figure

5. Box plot of post-oxygenator / filter( Arterial) GME count data. Box plot showing the total number of GME measured for 3 min( 180 s) by the“ arterial” sensor for suction flow rate and reservoir levels, including all reservoir types( Medtronic Affinity Fusion, Liva Nova SORIN Inspire 8F, and Terumo CAPIOX FX25 Advance). Roller pump suction flow rate: 25 RPM( 0.32 L / min), 50 RPM( 0.65 L / min), 75 RPM( 0.99 L / min), and 100 RPM( 1.32 L / min), and reservoir level( mL) is on the x-axis, and total bubble number is on the y-axis. The lines in each boxplot represent the median values, and the black circles represent the averages.

Table 4. Statistical analysis for the“ arterial” GME sensor for all test reservoirs combined. This shows post-hoc comparisons of the average difference in GME number by suction speed 25 RPM( 0.32 L / min), 50 RPM( 0.65 L / min), 75 RPM( 0.99 L / min), and 100 RPM( 1.32 L / min). Statistically significant differences are p <. 05, shown in bold, and adjusted using the Tukey HSD method.

the transmission of GME. This interaction effect was not evident with measurements from the arterial sensor.

The suction / vent flow rate should be continuously monitored and adjusted as needed during CPB. It must be high enough to prevent the surgical field from being flooded with blood, but low enough to minimize the admixture of air with blood. The reservoir level during CPB is influenced by several variables, including the patient’ s blood volume, circuit prime volume, and venous return. A minimum operating reservoir level is designated by the reservoir manufacturer( Table 1) and depends on the arterial flow rate and the desired reaction time to emptying.

This study demonstrated that more bubbles were detected at the venous( post-reservoir) sensor as suction speed increased. The integrated cardiotomy reservoir was unable to capture all the aerated blood from the sucker, and some of it passed out of the reservoir and into the centrifugal pump. At all three tested levels( 200 mL, 500 mL, and 1,000 mL), no statistically significant change in post-cardiotomy bubble count was detected when suction speed was maintained between 25 and 50 RPMs. This corresponds with a flow rate of less than 0.65 L / min( Table 2). Increasing the suction flow to 75 RPMs( approximately 1.0 L / min) significantly changed the bubble count at 200 mL and 500 mL levels. At the maximum suction speed evaluated( 100 RPM or 1.32 L / min), significant changes in bubble count were found at all three levels. Interestingly, even with 1 L of blood in the reservoir, bubbles bypassed the venous sensor at the maximum suction flow.

Table 4 displays the results from the arterial sensor( postoxygenator / filter). As expected, most bubbles measured as they exited the reservoir were either trapped by the integrated arterial filter or diffused across the hollow fiber membrane. Hence, the