Forearm tattoo removal and previous keloid scarring on shoulders/chest safety?

If you didn't keloid during from the tattoo placement then you aren't likely to keloid from laser removal. The easiest way to find out is to start with a test spot. I would also recommend using lower energy settings to help reduce the risk. It will take a bit longer to remove but it will be worth it.

We have treated many patients that have keloid scars that have not had the issue with tattoo removal. You have not stated your skin type or color. That being said be sure you go to a well experienced medical center. advise them of your condition. make sure they go slowly at first with less energy than they would normally use to see the effect. blisters dont usually have issue with scarring.  depending on many factors that your physician will have to evaluate they will be able to better answer your specific needs.
good luck

Compared to a patient with no history of keloids, you would be at increased risk.  Typically, the chest/shoulders is a region predisposed to poor healing and keloid formation due to higher wound tension.  The forearms would be at lower risk.  Consult with an experienced and board-certified cosmetic physician.  Laser tattoo treatments does not always result in blister formation.  Conservative parameters can be used to try to minimize adverse effects.