A cannula assembly for insertion in a blood vessel includes a cannula and a dilator. The cannula has a proximal end, a distal end, and a lumen extending therebetween. The dilator, which is telescopically received in the lumen of the cannula, includes proximal and distal ends, a passage extending between...http://www.google.fr/patents/US6120494?utm_source=gb-gplus-shareBrevet US6120494 - Method of placing a cannula
