Cannula having reverse flow tip

DETAILED DESCRIPTION The cannula according to the invention overcomes the problems of the prior art by providing a multi-lumen cannula with independently reinforced lumens so that dramatically different fluid pressures can be accommodated in the same multi-lumen cannula.
In addition, the cannula according to the invention achieves some of the desirable goals of cardiac surgery by minimizing the number of incisions which must be created in the heart and vessels leading to and from the heart as well as by reducing trauma to the body through redirection of the fluid flow as it exits the cannula.
In accordance with one embodiment of the invention, a cannula for conducting fluid to a body is provided.
The cannula includes a cannula body and a cannula tip.
The cannula body has proximal and distal ends, and a lumen extending therebetween.
The lumen is adapted to receive the fluid flowing therethrough.
The cannula tip is coupled to the distal end of the cannula body and includes a side wall having a plurality of fluid outlets formed therein.
Each fluid outlet is directed toward the proximal end of the cannula body to reverse the flow of fluid exiting the cannula by an obtuse angle from the original direction of flow.
In another embodiment of the invention, a multi-lumen cannula assembly includes first and second sub-cannulas.
Each sub-cannula has proximal and distal ends, and a lumen extending therebetween.
The second sub-cannula is adhered to a portion of the first sub-cannula to create a septum separating the lumens of the first and second sub-cannulas.
The first sub-cannula also includes a reinforcement to resist radial deflection of the lumen, and a cannula tip, located at the distal end.
The cannula tip has a plurality of fluid apertures formed therein.
The reinforcement of the first sub-cannula resists deflection of the septum as a result of differing fluid pressure levels inside the lumens.
The second sub-cannula, which is adhered to a portion of the first sub-cannula, includes a cannula tip located at a distal end