Praise be to Allah.
It is not permissible to remove or withhold the respirator from a patient except in the case where it has been definitely established that he comes under the ruling of one who is dead, because all brain function has completely ceased, or his heart and breathing have completely stopped in such a way that the doctors have determined is irreversible.
It says in a statement of the Islamic Fiqh Council belonging to the Muslim World League, issued during its 10th session on 24/2/1408 AH:
In the case of a patient whose body has been hooked up to life support, it is permissible to remove it if all his brain functions have ceased completely, and a committee of three specialist, experienced doctors have determined that this cessation of function is irreversible, even if the heart and breathing are still working mechanically with the help of the machine. But he cannot be ruled dead according to sharee’ah until his breathing and heart stop completely, after the machine is removed. End quote.
It says in a statement of the Islamic Fiqh Council belonging to the Organisation of the Islamic Conference, that was held during its third conference in ‘Ammaan, the capital of Jordan, 8-13 Safar 1407 AH/11-16 October 1986 CE, after the presentation of all points of view on the topic of life support machines and listening to detailed explanations from specialist doctors: From a shar’i point of view, a person is considered to have died, and all the rulings that apply to death come into effect at that point, when one of the following signs appear:
1.When his heart and breathing stop completely and the doctors rule that this cannot be reversed
2.When all his brain functions cease completely and specialist, experienced doctors determine that this is irreversible and necrosis has begun to occur in the brain.
In this case it is justified to remove life support from the patient, even if some of these organs, such as the heart, are still working mechanically due to the action of the equipment. End quote.
So-called mercy killing is not permissible, whether it is done by withholding treatment from the patient or by any other means. It comes under the heading of haraam killing which the Prophet (blessings and peace of Allah be upon him) regarded as one of the major sins. There are no exceptions to that except what has been mentioned above concerning one who comes under the rulings of those who have died.
As for withholding treatment on which life depends on the basis of reducing the suffering of the patient and putting an end to his pain and suffering, it is not permissible and this comes under the heading of haraam killing.
Al-Bahooti (may Allah have mercy on him) said in Kashshaaf al-Qinaa’ (5/495): It is not permissible to kill it -- meaning the animal -- or to slaughter it for the sake of giving it relief, because it is wealth so long as it is alive, and slaughtering it is destroying it, and it is forbidden to destroy wealth, like the human who is suffering from painful disease, because his life is protected by sharee’ah so long as he is still alive. End quote.
We ask Allah to heal your mother and grant her well-being.
And Allah knows best.