Autopsies, or other post-mortem operations, including removal of tissue for transplanting, may be performed on the body of a deceased patient only by direction of the officer in charge and only if consented to in writing by a person authorized under the law of the State in which the station or hospital is located to permit an autopsy or such other post-mortem operation under the circumstances of the particular death involved. Restrictions or limitations imposed by the person consenting thereto on the extent of the autopsy or other post-mortem operation shall be observed. Documents embodying consent shall be made a part of the clinical record.