A common complication of venipuncture is pain. This is usually mild, but occasionally the needle will strike a nerve, causing severe pain. Permanent nerve injury can result. Nerve injury occurs most often when blood is drawn from antecubital veins or veins in the bend of the arm on the inside of the elbow. This type of injury is rare but can cause significant discomfort for patients. On rare occasions, the needle can hit a small sensory nerve that runs close to the vein when it enters the arm. If this happens, the patient experiences an electric shock-like pain. While that may be the extent of the damage, it can linger for up to several weeks with a tingling feeling, but eventually it heals. Nerve injury does not affect the function of the hand or arm, although the patient may experience shooting pains in the affected arm. To avoid hitting this nerve, deep needle sticks should be avoided.

PHLEBOTOMIST RESPONSE
Do not draw blood on the side where lymph nodes have been removed (mastectomy).
These patients have significantly reduced fluid balance in the respective limb.  Aggravation of the limb, even by something as seemingly minor as a needle puncture, can result in lingering, even permanent pain. 

The patient may experience sudden extreme pain during venipuncture if a nerve is touched which may radiate above and below the puncture site to the fingertips and the shoulder, sometimes all the way to the chest.  Pain may last for several hours or even days.                                      

Avoid excessive, deep or blind probing with needle.  When this pain presents itself, terminate the puncture rather than to continue probing with the needle.  Refer patient to medical provider for further evaluation and follow-up.