| 主权项 |
1. An improved cannula assembly, comprising:
cannula having a first length and first inner diameter, the first cannula having at least a flexible distal portion; a trochar having a second length and second diameter, the trochar having a sharp distal position capable of puncturing through skin and into a blood vessel of a patient and sized such that the trochar may be inserted within the first cannula and extend beyond the distal portion thereof; and at least one flexible second cannula for insertion in the first cannula, the second flexible cannula sized to extend beyond the distal portion of the first cannula for a predetermined length within the blood vessel of the patient. |
