Intracardial injections, commonly know as heart sticks, is a rather inhumane way to euthanize an animal that is not comatose(or nearly comatose) or heavily sedated. A needle and syringe containing sodium pentobarbital is passed through the chest wall and severely layers of muscle into the heart. However on an animal that isn't sedated or comatose this is hard to do because the body is in constant motion. It's not uncommon for the person administering the injection to miss and accidentally punctures the lungs and causes them to fill up with fluid. This is a VERY painful way to die. In a shelter there is no reason for this to be done!