The paper describes three types of artificial gas exchange techniques for respiratory failure; extracorporeal membrane oxygenation (ECMO) for acute respiratory failure address the problem of oxygenation and CO2 removal; arteriovenous carbon dioxide removal (AVCO 2) for acute and respiratory failure with residual function, achieve total CO2 removal supplement native lung apneic oxygenation; paracorporeal artificial lung (PAL) for bridging to lung transplantation, perform total gas exchange (oxygenation and CO2 removal)