I started a peripheral IV saline lock in a relatively healthy patient in his mid forearm cephalic vein on the first attempt. I used a 20G, one inch BD Insyte catheter. Used 2ml of normal saline to flush. During catheter insertion, the patient reported pain. Approximately four to five minutes later, the patient continued to report pain, though his pain level had decreased. I removed the catheter and placed another in his left hand without incident. After the patient's procedure, I assessed the initial, troubling site and observed mild swelling. The patient reported mild pain to palpation adjacent to the insertion site. I applied an ice pack and the swelling diminished but did not disappear. The patient was discharged. The only infusate was the 2 ml flush. My rationale for the pain was nerve involvement. Would that explain the swelling?