Blood pressure can be measured lying down, but the following points should be noted before measuring blood pressure: 1. Patients should be asked to rest quietly for more than 15-20 minutes. 2. A quiet environment should be chosen, and the environment should not be too noisy. 3. Patients should be asked to avoid emotional tension, eliminate nervousness, and not be too emotional. 4. The arm of the blood pressure measurement should be kept at the same level as the patient’s heart when measuring blood pressure. Whether you choose to lie down or choose a seat, make sure the patient’s arm is at the same level as the heart. 5. Whether the patient is hypertensive or not, the blood pressure of the two arms is different when measuring blood pressure, usually the blood pressure of the dominant arm is higher than the other arm, higher than 15-20 mmHg, which is a normal physiological phenomenon.