A health care decision by another is authorized under this chapter for an adult person who is incapable of giving informed consent to health care. A person is incapable of giving informed consent to health care if:
A determination by the attending physician that a person is incapable of giving informed consent is effective until there is a subsequent determination, either by the attending physician, or by the circuit court, that the person is either capable of giving informed consent or that the diagnosis upon which the determination of incapacity was based is no longer valid. The attending physician may decline to make a determination as to either a person's capacity or incapacity to give informed consent and a health care provider may, but need not, rely on any such determination.
Any determination by an attending physician shall be in writing, shall be signed by the attending physician and shall be made a part of the person's medical record.
SDCL 34-12C-2