Blood flow/pump rotation ratio as an artificial lung performance monitoring tool during extracorporeal respiratory support using centrifugal pumps.
OBJECTIVE
To analyze the correlations of the blood flow/pump rotation ratio and the transmembrane pressure, CO2 and O2 transfer during the extracorporeal respiratory support.


METHODS
Five animals were instrumented and submitted to extracorporeal membrane oxygenation in a five-step protocol, including abdominal sepsis and lung injury.


RESULTS
This 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).


CONCLUSIONS
Blood 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.
Departamento de Emergências Clínicas, Unidade de Terapia Intensiva, Hospital das Clínicas de São Paulo, São Paulo, SP, Brasil.
Marcelo
M
Park
Departamento de Emergências Clínicas, Unidade de Terapia Intensiva, Hospital das Clínicas de São Paulo, São Paulo, SP, Brasil.
Pedro Vitale
PV
Mendes
Departamento de Emergências Clínicas, Unidade de Terapia Intensiva, Hospital das Clínicas de São Paulo, São Paulo, SP, Brasil.
Adriana Sayuri
AS
Hirota
Departamento de Emergências Clínicas, Unidade de Terapia Intensiva, Hospital das Clínicas de São Paulo, São Paulo, SP, Brasil.
Edzangela Vasconcelos
EV
dos Santos
Unidade de Terapia Intensiva Respiratória, Hospital das Clínicas de São Paulo, São Paulo, SP, Brasil.
Eduardo Leite Vieira
EL
Costa
Departamento de Emergências Clínicas, Unidade de Terapia Intensiva, Hospital das Clínicas de São Paulo, São Paulo, SP, Brasil.
Luciano Cesar Pontes
LC
Azevedo
D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology; D002245:Carbon Dioxide / Q000378:metabolism*; D004195:Disease Models, Animal; D015199:Extracorporeal Membrane Oxygenation / Q000379:methods*; D005260:Female; D055370:Lung Injury / Q000503:physiopathology / Q000628:therapy*; D010100:Oxygen / Q000378:metabolism*; D012129:Respiratory Function Tests; D018805:Sepsis / Q000628:therapy; D013552:Swine
D002245:Carbon Dioxide; D010100:Oxygen