How much monetary compensation should I request for a faulty medical device?

This is not an easy question to answer because the amount that you pick is going to release the company from all liability.  You need to know what the full extent of the damages are before you pick a number so to speak.  I suggest that you consult with a doctor to determine the effects- long term and short term before and the need for future medical treatment before settling.  if you settle and some comes up in the future you will be barred as a matter of law from seeking additional compensation from this company.  I also suggest talking to a lawyer and a showing him all the medical records to help come up with a proper figure that reflects the injuries cause by the device.