The PR on a monitor usually refers to the pulse rate, or pulse rate for short, which is a value that reflects how fast or slow the human pulse is beating, with a normal range of 60-100 beats per minute. For most normal people, the pulse rate is the same as the heart rate, so some monitors may replace PR with HR (heart rate). cardiac monitor is a non-invasive instrument that continuously monitors the patient’s hemodynamic status, and is usually able to record most of the human vital signs parameters, including heart rate, pulse rate, blood pressure, oxygen saturation, ECG waveform, etc. Some monitors can also reflect the patient’s real-time body temperature changes. Pulse is usually expressed as PR, and the normal value is 60-100 beats/min. If it is >100 beats/min, it indicates that the patient may have tachycardia; if it is <60 beats/min, it indicates that the patient may have bradycardia. Blood pressure is usually non-invasive blood pressure measured by cuff; oxygen saturation is measured by the oxygen content in the fingertip blood, reflecting the oxygenation status of the body; ECG waveform helps to observe whether the patient has various types of arrhythmias. Patients with critical cardiovascular diseases, cerebrovascular diseases, perioperative patients or patients with potentially life-threatening conditions require continuous ECG monitoring during hospitalization. The nurse usually connects the ECG monitor, opens the instrument at one end, places a new patch on the patient's precordial area and abdomen at the other end, clamps the oxygen probe on the patient's finger, and starts the instrument with the cuff on the arm, and the ECG monitor screen will show various vital sign parameters, which can be recorded to the patient's vital signs.