Extracorporeal pumpless interventional lung assist in clinical practice: determinants of efficacy

Abstract

Respiratory acidosis can become a serious problem during protective ventilation of severe lung failure. A pumpless arteriovenous interventional lung assist (iLA) for extracorporeal carbon dioxide removal has been used increasingly to control critical respiratory situations. The present study sought to evaluate the factors determining the efficacy of iLA and calculate its contribution to gas exchange.In a cohort of 96 patients with severe acute respiratory distress syndrome, haemodynamic parameters, oxygen consumption and carbon dioxide production as well as gas transfer through the iLA were analysed.The measurements demonstrated a significant dependency of blood flowviathe iLA device on cannula size (mean±sd1.59±0.52 L·min−1for 15 French (Fr), 1.94±0.35 L·min−1for 17 Fr, and 2.22 ±0.45 L·min−1for 19 Fr) and on mean arterial pressure. Oxygen transfer capacity averaged 41.7±20.8 mL·min−1, carbon dioxide removal was 148.0±63.4 mL·min−1. Within two hours of iLA treatment, arterial oxygen partial pressure/inspired oxygen fraction ratio increased significantly and a fast improvement in arterial carbon dioxide partial pressure and pH was observed.Interventional lung assist eliminates ∼50% of calculated total carbon dioxide production with rapid normalisation of respiratory acidosis. Despite limited contribution to oxygen transfer it may allow a more protective ventilation in severe respiratory failure.

Interventional Lung Assist Application in a Patient with Acute Respiratory Distress Syndrome: Case Report

“…10 Yine bu çalışmada, ILA'dan geçen kan akımının önemli olduğu, kalp debisinin, ortalama arter basıncının korunması gerektiği vurgulanmış-tır. Kopp ve ark.…”

Extracorporeal Pulmonary Support in Severe Pulmonary Failure in Adults

“…The system's oxygen transfer capacity is physically limited and achieves no more than 10% to 15% of total oxygen consumption (14). Severe hypoxemia is therefore a contraindication for iLA; ECMO is indicated instead.…”

Extracorporeal Carbon Dioxide Removal (ECCO2R) in Respiratory Failure: An Overview, and where Next?

“…The flow rate of oxygen is increased in a stepwise fashion up to a maximum of 12 L/min. The shunt is usually created between the femoral 6 demonstrated that: • The primary determinants of blood flow through the system are: the dimensions of the cannulae (in accordance with the Hagen-Poisseuille equation), the arteriovenous pressure gradient (rather than cardiac output), and the resistance of the membrane.…”

“…The previously mentioned study by Muller et al looked specifically at the O 2 and CO 2 transfer that occurred via the Novalung iLA ® (AV-ECCO 2 R) in 96 patients with ARDS. 6 Blood samples were taken before and after the AV-ECCO 2 R device in order to calculate the O 2 and CO 2 content of blood at these points. The flow of blood through the device was also measured and hence the rate of gas transfer could be calculated using Fick' s principle.…”