Can periorbital swelling post hair transplant (temporal, traction alopecia) cause permanent disfiguration/pigmentation issues?

I'm concerned about scarring hyper/hypopigmentation after hair transplant. After an unrelated surgery (abdominal lipo), my friend had swelling on her breast which resulted in swelling, and subsequently a ruptured blister and hyperpigmentation. Is this possible with hair transplant? If so what is the probability of this happening? I have seen terrible pictures of post-transplant facial/periorbital edema and i'm vey worried!!