Just stay in the USA sweetie, engineering salaries are low in poland. Your only hope is to find an American company in poland that does biomedical engineering...
I wouldn't give up. I would search around on the internet, find some university's in PL that specialize in this area, and see we what info they can offer you. Research your field, and see how many companies you can come up with, and send them your resume, or ask them for internships. Are you done with school? Bachelor's? Master's?
Having studied engineering myself and having visited poland many times (family) i can tell you that there are engineering jobs in poland, but they do not pay very well. What's worst, the polish workplace is a much stressful (employees treated like garbage and laid off freely - doesn't always happen, but its quite common) environment then the one i'm used to here in canada.
As i've mentioned before on these forums, it's best to find a foreign company in poland to work for, since quite often they tend to pay better and treat their employees much better as well.