title: Superior vena cava drainage improves upper body oxygenation during veno-arterial extracorporeal membrane oxygenation in sheep.
abstract: BACKGROUND
  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.
authors.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.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. xt.hou@ccmu.edu.cn.
authors.forename: Xiaotong
authors.initials: X
authors.lastname: Hou
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. yangxiaofang_1985@163.com.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. yangxiaofang_1985@163.com.
authors.forename: Xiaofang
authors.initials: X
authors.lastname: Yang
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. zhongtaodu@126.com.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. zhongtaodu@126.com.
authors.forename: Zhongtao
authors.initials: Z
authors.lastname: Du
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. xingjl@163.com.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. xingjl@163.com.
authors.forename: Jialin
authors.initials: J
authors.lastname: Xing
authors.affiliation: Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. 1737356020@qq.com.|Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. 1737356020@qq.com.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. jcj525259@126.com.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. jcj525259@126.com.
authors.forename: Chunjing
authors.initials: C
authors.lastname: Jiang
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. wangjinhong002@163.com.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. wangjinhong002@163.com.
authors.forename: Jinhong
authors.initials: J
authors.lastname: Wang
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. xingtc100@sohu.com.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. xingtc100@sohu.com.
authors.forename: Zhichen
authors.initials: Z
authors.lastname: Xing
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. 9300479@163.com.
authors.forename: Shuanglei
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Anaesthesia, Beijing New Century Women's and Children's Hospital, Wangjing North Road, Beijing, 100029, P.R. China. xiaokui.li@ncich.com.cn.
authors.forename: Xiaokui
authors.initials: X
authors.lastname: Li
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. 13581976632@163.com.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. 13581976632@163.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Yang
authors.affiliation: Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, 2 Anzhen Road, Beijing, 100029, P.R. China. wanghong224@gmail.com.|Beijing Institute of Heart Lung and Blood Vessel Diseases, 2 Anzhen Road, Beijing, 100029, P.R. China. wanghong224@gmail.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.affiliation: Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, 8 East Jing Shun Road, Beijing, 100015, P.R. China. zenghui@ccmu.edu.cn.|Beijing Key Laboratory of Emerging Infectious Diseases, Jingshundongjie 8, Beijing, 100015, P.R. China. zenghui@ccmu.edu.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Zeng
mesh_terms: D000818:Animals; D001027:Aortography; D002339:Carotid Arteries / Q000502:physiology; D002404:Catheterization / Q000379:methods; D004195:Disease Models, Animal; D015199:Extracorporeal Membrane Oxygenation / Q000379:methods*; D005263:Femoral Artery / Q000000981:diagnostic imaging / Q000502:physiology; D010100:Oxygen / Q000097:blood*; D012039:Regional Blood Flow / Q000502:physiology*; D012131:Respiratory Insufficiency / Q000628:therapy; D012756:Sheep; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging / Q000502:physiology; D014683:Vena Cava, Superior / Q000000981:diagnostic imaging / Q000502:physiology
chemical_list: D010100:Oxygen