The technique used by our group for the extraction of the canine autoperfused heart-lung block is described. This was used in 30 dogs, having a success rate of 24 total extractions and function times from 30 minutes to 13 hours." The complications observed were: arterial rupture upon cannulation, aortic rupture upon binding, ventricular fibrillation before completing extraction, and bleeding of the block with subsequent emptying of the reservoir. It is concluded that the technique described is adequate for the extraction of the canine block, although it is still necessary to know better its hemodynamic, biochemical and respiratory behavior.