Final answer:
When a potential donor is unwilling to donate, respect their decision and seek alternative donors. Relatives are preferred for donation due to compatibility which reduces rejection, and immunosuppression is used to support transplant success.
Step-by-step explanation:
The scenario presented involves Mr. Liver, a 35-year-old man facing hepatic failure and urgently needing a liver transplant. His brother is a highly compatible HLA-matched donor but is unwilling to undergo the partial donation surgery. In such a medical and ethical situation, the appropriate action would be to respect the brother's autonomy and decision not to donate his liver. Consequently, other potential donors must be explored, and any possibility of organ donation must continue to be voluntary, adhering to ethical standards and the law. As tough as it is, it's crucial to communicate with the patient about his condition and prognosis without available transplantation honestly.
Blood relatives are often preferred as organ donors because they are more likely to be compatible, thus reducing the risk of tissue rejection. The role of immunosuppression is to prevent the immune system from attacking the transplanted organ, which is critical for the success of the transplant.