All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
Medicine is one of the crucial professions. It is only those who are well-grounded in knowledge in medicine and who are trustworthy and competent, who are permitted to practice it. A practitioner who is not competent in his profession is responsible for any death or amputation of any limb he might cause due to his/her incompetence.
However, if he/she masters his/her profession and follows the correct methods in treatment and does not make any mistake, or cause any injury or pain, in this case, he/she is not sinful and is not responsible for what occurs.
However, if you knew that he/she did not master this, or did not know the health condition of the patient, and you agreed with him/her in what he/she did, and caused harm to the patient, then you are both sinful and both of you should repent.
Anyway, as long as there was a specialist, you should have sought his advice before acting.
We ask Allaah to forgive us and you and all the Muslims, and cure all Muslim patients as He is the Most Generous, Oft-Forgiving, and Most Merciful.
For more benefit, please refer to Fatwa 87930.
Allaah Knows best.