Take a piece of banana peel and tape it to the bruise yellow side out. Should clear it up.
Bruises are consistent with an accidental puncture of the vein by the trochar while being inserted. It's not the nicest thing, but they happen. Damage may be done to a vein by infused medications, that may be corrosive. This is why some meds have to be infused over long periods. If there is damage from running in such a medication too fast the primary symptom is inflammation, which is characterized by redness, extending the length of the vein, or at least in a line from the medication entry point. A bruise, in the other hand, usually represents blood leakage from a specific spot, usually no more than an half inch or two up from the trochar entry point. The bruise is not normal, but should heal, as will the vein.