In his response to your issue, Dr. Rajab Abu Mleeh stated:
“If a physician, due to his ignorance or carelessness, was the cause of patient’s death, he has to pay blood money (Diyyah) and make expiation of fasting two months, since this is considered an accidental and unintentional killing.
However, if he is experienced in the field of performing operations and the case of the patient can bear it, in addition to that, there was no any negligence or carelessness; he does not have any responsibility and he is not obliged to pay blood compensation or make any expiation.
The issue is the same if he causes any damage to a patient’s organ and he has to tell him about what happened. If the patient’s relatives forgive him, he has to ask for Allah’s forgiveness and make expiation, since it is the right of Allah. Thus, he will not insha’Allah be punished in the Day of Judgment.”