68 S . Robertson and K . White : J Extra Corpor Technol 2024 , 56 , 65 – 70
Figure 3 . In Vitro setup for Experiments 3 and 6 simulating volume transfused from a pressurized bag of saline , through a pressure transducer , to an empty buretrol solution set with negative 50 mmHg of vacuum applied .
to an Edwards TruWave transducer monitored by a Terumo System One heart and lung machine ( Terumo Cardiovascular , Ann Arbor , MI , USA ). The vacuum regulator was turned on and the pressure inside the buretrol solution set was regulated to �50 mmHg . After 24 h the volume was removed and recorded .
Experiments 4 , 5 , and 6 were set up the same as experiments 1 , 2 , and 3 , respectively . In these trials , the Snap-Tab was pulled for 10 s and the expelled fluid volume was recorded .
Ten seconds was selected as a time that was reliably repeatable and provided a clearly measurable amount of volume to report . All experiments were repeated five times .
The TruWave pressure transducer with blue Snap-Tab displaces 3 mL ± 1 mL passively every hour across the internal flush device when connected to an IV bag pressurized to 300 mmHg [ 8 ]. Experiment 1 results confirm this claim ( Table 1 ). The findings from experiments 2 and 3 allow clinicians to extrapolate how much volume is passively transfused