ObjectiveTo analyze the correlations of the blood flow/pump rotation ratio and the
transmembrane pressure, CO2 and O2 transfer during the
extracorporeal respiratory support.MethodsFive animals were instrumented and submitted to extracorporeal membrane
oxygenation in a five-step protocol, including abdominal sepsis and lung
injury.ResultsThis study showed that blood flow/pump rotations ratio variations are dependent on
extracorporeal membrane oxygenation blood flow in a positive logarithmic fashion.
Blood flow/pump rotation ratio variations are negatively associated with
transmembrane pressure (R2 = 0.5 for blood flow = 1500mL/minute and
R2 = 0.4 for blood flow = 3500mL/minute, both with p < 0.001) and
positively associated with CO2 transfer variations (R2 = 0.2
for sweep gas flow ≤ 6L/minute, p < 0.001, and R2 = 0.1 for
sweep gas flow > 6L/minute, p = 0.006), and the blood flow/pump rotation ratio
is not associated with O2 transfer variations (R2 = 0.01 for
blood flow = 1500mL/minute, p = 0.19, and R2 = - 0.01 for blood flow =
3500 mL/minute, p = 0.46).ConclusionBlood flow/pump rotation ratio variation is negatively associated with
transmembrane pressure and positively associated with CO2 transfer in
this animal model. According to the clinical situation, a decrease in the blood
flow/pump rotation ratio can indicate artificial lung dysfunction without the
occurrence of hypoxemia.