My Mother has Respiratory problems and sometimes her breathing rate goes to 40 and stays there awhile then it comes back down. She is on oxygen 24 hrs. a day. Her beats per minute range from 38 to 80, she is A Fib. Was told to give her 1/4 cc of liquid Morphine when her respiration was high for 20 minutes. Concerned about what the Morphine will do to her being her beats per minutes is up and down. So how safe is it for her to take the Morphine.