Because the goal of the procedure is to place a plastic catheter into the vein. If you insert the needle/catheter vertically you will go through the vein. If you angle on insertion once placement in the vein is confirmed you can slide the hollow catheter off of the needle into the vein. The veins used for most IV's normally lie just under the skin. For this reason a shallow angle of insertion is used.
25 degrees
15-30 degrees
45 degrees
90- degree
90 degree angle
angle of pull is the angle between muscle insertion and the bone on which the muscle inserts
Bend the cable to a 45 degree angle after partial insertion into the terminal
The needle should form a 15 to 30 degree angle with the surface of the arm.
90 degree
About a right angle (90 degrees) to the chest, intercostal, into the pleural lining and not into the lung.
Inserts a needle at the wrong angle or uses a large-bore needle
3/8
usually the veinipuncture is using a 21 or 22 gauge needle at about a 30 degree or less angle.