a catheter comprising a unitary tube formed solely of a single material, the unitary tube having a length and a wall thickness made from the single material throughout a proximal tube portion, a distal tube portion, and a transition region, which is disposed therebetween;

the proximal tube portion comprising an exterior surface defining an outside diameter, an interior surface defining an inside diameter of the catheter, and a length;

the distal tube portion comprising an exterior surface that defines an outside diameter, an interior surface that defines an inside diameter of the catheter, a length, a closed catheter tip formed by an end cap and at least one lateral opening defined radially on the distal tube portion near the closed catheter tip for passing a fluid therethrough; and

a cannula comprising a tip having a bend at a distal end for non-coring made, at least in part, from a metal material, the catheter configured such that when the catheter is positioned within the cannula the distal tube portion of the catheter extends beyond the tip of the cannula;

wherein the outside diameter, the inside diameter, and the length of the distal tube portion are made less than said corresponding outside diameter, inside diameter, and length of the proximal tube portion by stretching the distal tube portion, wherein the transition region is singularly formed between the proximal and distal tube portions and has a wall thickness adjacent the proximal tube portion that is greater than a wall thickness that is adjacent the distal tube portion; and wherein the interior surface of the proximal tube portion and the interior surface of the distal tube portion of the catheter are exposed to a common lumen.