Extracorporeal lung assist (ECLA) is an established treatment of severe pulmonary failure. Since extracorporeal perfusion is applied in a long-term fashion in this setting, the negative impact on blood compounds is of tremendous importance. Pumpless arteriovenous ECLA (av-ECLA) is an alternatively introduced technique that focuses on reduced blood traumatization. However, due to determining technical and physiological aspects, its clinical application is limited to a highly selected group of patients. Membrane oxygenators with minimal pressure gradients, as well as stable patients' haemodynamics providing a sufficient cardiac output, are the most important prerequisites. With respect to recent reports, characteristic features of av-ECLA, with special emphasis on its physiological background, are reviewed. Accordingly, reasonable indications for its beneficial use are discussed. It is concluded that av-ECLA is a feasible technique when its limitations are accepted. For adequate clinical use, more data concerning indications, as well as time- and technique-related directions are required.

Pumpless arteriovenous extracorporeal lung assist: what is its role?

Pumpless arteriovenous extracorporeal membrane oxygenation: A novel mode of respiratory support in a lamb model of congenital diaphragmatic hernia.

In eight anesthetized mongrel dogs with thiopental, diazepam and pancuronium bromide, ECMO with arterio-venous shunt was performed under hypoventilation for 24 hours. The blood flow through the ECMO which was connected between the femoral artery and vein was approximately 40% of the cardiac output. Hypoventilation was induced to decrease PaO2 to around 40mmHg and increase PaCO2 to around 80 mmHg. The ECMO improved the abnormal parameters, which were induced by the hypoventilation, to almost normal range (PaO2 80mmHg, PaCO2 30mmHg) for 24 hours. Furthermore, there were no abnormalities in cardiovascular and other systems during ECMO.

[A simple method of extracorporeal membrane oxygenation (ECMO)--2: The effects of ECMO (arterio-venous shunt) on the arterial blood gases measured for 24 hours].

Y Iwasaki

Papers

[A simple method of extracorporeal membrane oxygenation (ECMO)--2: The effects of ECMO (arterio-venous shunt) on the arterial blood gases measured for 24 hours].