a patient was admitted several weeks ago with an acute myocardial infarction and subsequently underwent coronary artery bypass grafting surgery. since a cardiac arrest 5 days ago, the patient has been unresponsive. an electroencephalogram shows no meaningful brain activity. after a family conference, the practitioner orders a do-not-resuscitate (dnr) order, and palliative care is begun. how does this affect the patient's treatment?