Final answer:
If you feel a 'crunching' sensation as you compress the sternum during CPR, you should immediately stop compressing. The sensation could indicate broken ribs or a broken sternum, so it's crucial to avoid causing further harm to the patient.
Step-by-step explanation:
If you feel a 'crunching' sensation as you compress the sternum during CPR, you should immediately stop compressing. The 'crunching' sensation, also known as crepitus, may indicate the presence of broken ribs or a broken sternum. Continuing to compress in this case could inflict further damage on the patient. It is important to reassess the positioning of your hands and adjust accordingly to avoid causing harm.