Comparative Study on the Noninvasive Blood Pressure and Invasive Blood Pressure in Hypertensive Patients

Objective To explore the error and causes of measurements of blood pressure by mercyry sphygmomanometer in the patients with hypertension. Methods The arterial blood pressure of 20 hypertensive patients and 20 normal persons were measured by mercyry sphygmomanometer and invasive monitoring simultaneously at 7:00～8:00 am, 6 times each measurement for every person under fasting status. Results In hypertensive patients, the systolic pressure was lower by about 10 mmHg by sphygmomanometer method than by invasive monitoring ( P 0.01), but no difference in diastolic pressure was found between two methods. In normal persons, systolic pressure was lower by about 6 mmHg ( P 0.01 ) and diastolic pressure was higher by about 9 mmHg ( P 0.05). Conclusion There are some errors in measuring blood pressure by sphygmomanometer method. Apparent error is found in systolic pressure in patients with hypertension, but not in diastolic pressure.