Cardiovascular cannula

A venous drainage cannula assembly for insertion into the superior and inferior vena cavae through a single incision in the right atrium, comprising:

• an elongated resilient tube including a hollow body leading from an open outward end along a longitudinal axis, inwardly to an integral bifurcated tube end, the bifurcations forming two branches joining integrally with the hollow body at a crotch section of the tube;
• wherein the branches extend from the crotch to free open ends, with the length of the branches from the crotch to the free ends being sufficient to allow positioning of the free open ends within the superior and inferior vena cavae with the crotch situated within the right atrium and the incision edges engaging the hollow body toward the open outward tube end from the crotch;
• wherein the branches normally diverge from the crotch to the free tube ends, forming a "Y" configuration with the hollow tube body;
• and
• rigid obturator means having an elongated shaft slidably receivable within the length of the resilient tube and with straight extensions integral and coextensive with the shaft having a rounded end to be (a) received within the tube branches so the tube branches may be straightened by the rounded extension ends to extend parallel to the axis of the tube body as the obturator is inserted and moved relative to the tube toward the bifurcated end, and (b) allow the tube branches to spread back against the rounded extension ends to their normal diverging positions, all within the right atrium, thereby avoiding trauma to tissues at the incision upon insertion and withdrawal of the cannula.