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Superior vena cava drainage improves upper body oxygenation during veno-arterial extracorporeal membrane oxygenation in sheep.

Hou X, Yang X, Du Z, Xing J, Li H, Jiang C, Wang J, Xing Z, Li S, Li X, Yang F, Wang H, Zeng H - Crit Care (2015)

Bottom Line: SVC-FA achieved oxygen-rich blood return from the IVC to the RA without shifting the arterial cannulation.Subsequently, SO₂ of the SVC and the pulmonary artery increased (70.4 ± 1.0% and 73.4 ± 1.1%, respectively).With knowledge of this mechanism, we can apply better cannula configurations in clinical practice.

View Article: PubMed Central - PubMed

Affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. xt.hou@ccmu.edu.cn.

ABSTRACT

Introduction: Differential hypoxia is a pivotal problem in patients with femoral veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) support. Despite recognition of differential hypoxia and attempts to deliver more oxygenated blood to the upper body, the mechanism of differential hypoxia as well as prevention strategies have not been well investigated.

Methods: We used a sheep model of acute respiratory failure that was supported with femoral VA ECMO from the inferior vena cava to the femoral artery (IVC-FA), ECMO from the superior vena cava to the FA (SVC-FA), ECMO from the IVC to the carotid artery (IVC-CA) and ECMO with an additional return cannula to the internal jugular vein based on the femoral VA ECMO (FA-IJV). Angiography and blood gas analyses were performed.

Results: With IVC-FA, blood oxygen saturation (SO₂) of the IVC (83.6 ± 0.8%) was higher than that of the SVC (40.3 ± 1.0%). Oxygen-rich blood was drained back to the ECMO circuit and poorly oxygenated blood in the SVC entered the right atrium (RA). SVC-FA achieved oxygen-rich blood return from the IVC to the RA without shifting the arterial cannulation. Subsequently, SO₂ of the SVC and the pulmonary artery increased (70.4 ± 1.0% and 73.4 ± 1.1%, respectively). Compared with IVC-FA, a lesser difference in venous oxygen return and attenuated differential hypoxia were observed with IVC-CA and FA-IJV.

Conclusions: Differential venous oxygen return is a key factor in the etiology of differential hypoxia in VA ECMO. With knowledge of this mechanism, we can apply better cannula configurations in clinical practice.

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SO2in the ARF sheep model with different cannulations of VA ECMO. (A) The cannulation of IVC-FA in normal sheep did not affect the SO2 of the SVC, PA, aorta and IVC. After establishing ARF in these sheep, the SO2 of the SVC, PA and aorta decreased; the SO2 of the IVC remained high. (B) The SO2 in the ARF sheep model with SVC-FA, IVC-CA, and FA-IJV. ‘before’ indicates the SO2 value of IVC-FA. ‘after’ indicates the SO2 value after cannulation shifting. *Indicates P <0.01 between IVC-FA and mechanical ventilation or between IVC-FA and cannula-shifted sheep. ARF: acute respiratory failure; FA-IJV: an additional return cannula was added into the internal jugular vein on the basis of femoral veno-arterial extracorporeal membrane oxygenation; IVC-CA: a drainage cannula was inserted into the inferior vena cava and a return cannula was inserted into the carotid artery; IVC-FA: a drainage cannula was placed into the inferior vena cava through the femoral vein and a return cannula was inserted into the femoral artery; PA: pulmonary artery; SO2: oxygen saturation; SVC-FA: a drainage cannula was placed into the superior vena cava through the femoral vein and a return cannula was placed into the femoral artery; VA ECMO: veno-arterial extracorporeal membrane oxygenation.
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Fig2: SO2in the ARF sheep model with different cannulations of VA ECMO. (A) The cannulation of IVC-FA in normal sheep did not affect the SO2 of the SVC, PA, aorta and IVC. After establishing ARF in these sheep, the SO2 of the SVC, PA and aorta decreased; the SO2 of the IVC remained high. (B) The SO2 in the ARF sheep model with SVC-FA, IVC-CA, and FA-IJV. ‘before’ indicates the SO2 value of IVC-FA. ‘after’ indicates the SO2 value after cannulation shifting. *Indicates P <0.01 between IVC-FA and mechanical ventilation or between IVC-FA and cannula-shifted sheep. ARF: acute respiratory failure; FA-IJV: an additional return cannula was added into the internal jugular vein on the basis of femoral veno-arterial extracorporeal membrane oxygenation; IVC-CA: a drainage cannula was inserted into the inferior vena cava and a return cannula was inserted into the carotid artery; IVC-FA: a drainage cannula was placed into the inferior vena cava through the femoral vein and a return cannula was inserted into the femoral artery; PA: pulmonary artery; SO2: oxygen saturation; SVC-FA: a drainage cannula was placed into the superior vena cava through the femoral vein and a return cannula was placed into the femoral artery; VA ECMO: veno-arterial extracorporeal membrane oxygenation.

Mentions: Hemodynamic parameters, including HR and mean arterial pressure (MAP), were stable in each group of animals throughout the experiment and no significant differences were present among groups (see Additional files 1, 2, 3 and 4). Fifteen minutes after ARF, we observed that the SO2 of the SVC, PA and aorta were dramatically decreased (SVC: 85.3 ± 1.0% to 40.3 ± 1.0%, P <0.01; PA: 84.2 ± 1.1% to 33.9 ± 0.9%, P <0.01; aorta, 99.5 ± 0.2% to 35.3 ± 1.0%, P <0.01), whereas the SO2 of the IVC remained stable (83.7 ± 1.2% to 83.6 ± 0.8%, P = 0.83). Thus, similar to the clinical cases, upper body hypoxia occurred in the sheep model with ARF supported with IVC-FA (Figure 2A).Figure 2


Superior vena cava drainage improves upper body oxygenation during veno-arterial extracorporeal membrane oxygenation in sheep.

Hou X, Yang X, Du Z, Xing J, Li H, Jiang C, Wang J, Xing Z, Li S, Li X, Yang F, Wang H, Zeng H - Crit Care (2015)

SO2in the ARF sheep model with different cannulations of VA ECMO. (A) The cannulation of IVC-FA in normal sheep did not affect the SO2 of the SVC, PA, aorta and IVC. After establishing ARF in these sheep, the SO2 of the SVC, PA and aorta decreased; the SO2 of the IVC remained high. (B) The SO2 in the ARF sheep model with SVC-FA, IVC-CA, and FA-IJV. ‘before’ indicates the SO2 value of IVC-FA. ‘after’ indicates the SO2 value after cannulation shifting. *Indicates P <0.01 between IVC-FA and mechanical ventilation or between IVC-FA and cannula-shifted sheep. ARF: acute respiratory failure; FA-IJV: an additional return cannula was added into the internal jugular vein on the basis of femoral veno-arterial extracorporeal membrane oxygenation; IVC-CA: a drainage cannula was inserted into the inferior vena cava and a return cannula was inserted into the carotid artery; IVC-FA: a drainage cannula was placed into the inferior vena cava through the femoral vein and a return cannula was inserted into the femoral artery; PA: pulmonary artery; SO2: oxygen saturation; SVC-FA: a drainage cannula was placed into the superior vena cava through the femoral vein and a return cannula was placed into the femoral artery; VA ECMO: veno-arterial extracorporeal membrane oxygenation.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Fig2: SO2in the ARF sheep model with different cannulations of VA ECMO. (A) The cannulation of IVC-FA in normal sheep did not affect the SO2 of the SVC, PA, aorta and IVC. After establishing ARF in these sheep, the SO2 of the SVC, PA and aorta decreased; the SO2 of the IVC remained high. (B) The SO2 in the ARF sheep model with SVC-FA, IVC-CA, and FA-IJV. ‘before’ indicates the SO2 value of IVC-FA. ‘after’ indicates the SO2 value after cannulation shifting. *Indicates P <0.01 between IVC-FA and mechanical ventilation or between IVC-FA and cannula-shifted sheep. ARF: acute respiratory failure; FA-IJV: an additional return cannula was added into the internal jugular vein on the basis of femoral veno-arterial extracorporeal membrane oxygenation; IVC-CA: a drainage cannula was inserted into the inferior vena cava and a return cannula was inserted into the carotid artery; IVC-FA: a drainage cannula was placed into the inferior vena cava through the femoral vein and a return cannula was inserted into the femoral artery; PA: pulmonary artery; SO2: oxygen saturation; SVC-FA: a drainage cannula was placed into the superior vena cava through the femoral vein and a return cannula was placed into the femoral artery; VA ECMO: veno-arterial extracorporeal membrane oxygenation.
Mentions: Hemodynamic parameters, including HR and mean arterial pressure (MAP), were stable in each group of animals throughout the experiment and no significant differences were present among groups (see Additional files 1, 2, 3 and 4). Fifteen minutes after ARF, we observed that the SO2 of the SVC, PA and aorta were dramatically decreased (SVC: 85.3 ± 1.0% to 40.3 ± 1.0%, P <0.01; PA: 84.2 ± 1.1% to 33.9 ± 0.9%, P <0.01; aorta, 99.5 ± 0.2% to 35.3 ± 1.0%, P <0.01), whereas the SO2 of the IVC remained stable (83.7 ± 1.2% to 83.6 ± 0.8%, P = 0.83). Thus, similar to the clinical cases, upper body hypoxia occurred in the sheep model with ARF supported with IVC-FA (Figure 2A).Figure 2

Bottom Line: SVC-FA achieved oxygen-rich blood return from the IVC to the RA without shifting the arterial cannulation.Subsequently, SO₂ of the SVC and the pulmonary artery increased (70.4 ± 1.0% and 73.4 ± 1.1%, respectively).With knowledge of this mechanism, we can apply better cannula configurations in clinical practice.

View Article: PubMed Central - PubMed

Affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. xt.hou@ccmu.edu.cn.

ABSTRACT

Introduction: Differential hypoxia is a pivotal problem in patients with femoral veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) support. Despite recognition of differential hypoxia and attempts to deliver more oxygenated blood to the upper body, the mechanism of differential hypoxia as well as prevention strategies have not been well investigated.

Methods: We used a sheep model of acute respiratory failure that was supported with femoral VA ECMO from the inferior vena cava to the femoral artery (IVC-FA), ECMO from the superior vena cava to the FA (SVC-FA), ECMO from the IVC to the carotid artery (IVC-CA) and ECMO with an additional return cannula to the internal jugular vein based on the femoral VA ECMO (FA-IJV). Angiography and blood gas analyses were performed.

Results: With IVC-FA, blood oxygen saturation (SO₂) of the IVC (83.6 ± 0.8%) was higher than that of the SVC (40.3 ± 1.0%). Oxygen-rich blood was drained back to the ECMO circuit and poorly oxygenated blood in the SVC entered the right atrium (RA). SVC-FA achieved oxygen-rich blood return from the IVC to the RA without shifting the arterial cannulation. Subsequently, SO₂ of the SVC and the pulmonary artery increased (70.4 ± 1.0% and 73.4 ± 1.1%, respectively). Compared with IVC-FA, a lesser difference in venous oxygen return and attenuated differential hypoxia were observed with IVC-CA and FA-IJV.

Conclusions: Differential venous oxygen return is a key factor in the etiology of differential hypoxia in VA ECMO. With knowledge of this mechanism, we can apply better cannula configurations in clinical practice.

Show MeSH
Related in: MedlinePlus