FAQ's for Digital Sphygmomanometer (NIBP)

Presently, there are only two technologies available in order to access the patient's arterial blood pressure. Patients may apply automatic devices, which are based on the so-called " Oscillometric" technology or choose the devices, which derive from a so-called "Auscultatoric" technology.

The Auscultatoric technology, which is also referred as the "Riva-Rocci" method, bases on the pick-up of arterial sound bursts, which do occur, when blood samples flow under a cuff, which is wrapped around the patient's upper arm.

Most Auscultatoric devices are manual devices. That means, we try to detect the associated pulse sounds with a stethoscope and subsequently conclude on the Systolic and Diastolic blood pressures out of the sound pattern.

Since about 10 years, the Oscillometric technology has been introduced into the market.
The technology also bases on cuff wrapped around the limb, preferably on the upper arm of a patient. Upper arm devices turn out to deliver more precise measurement results.

All cuffs cover a bladder, which detects pulse related pressure changes. They derive from blood samples, which are streaming right under the cuff. These pressure changes are recorded in the course of a patient's measurement.

Basically only some specific conditions have to be met; the measurements have to be taken in rest condition, movements have to be avoided during the measurement process and the cuff position should be at heart level. There's no further skill necessary in order to perform these blood pressure measurements.

Most commonly patient's who are attempting to do a blood pressure measurement are not sufficiently in rest condition. Thus, sequential blood pressure results differ from each other. This limitation does not derive from a technological error, but from an imperfectly stable blood pressure itself.

Since any patient's arterial blood pressure may be changing dynamically, singular measurements should not be taken. It is advisable to do a series of repetition measurements, in order to define an actual blood pressure value.

The Oscillometric blood pressure measurement technology is sufficiently reliable to assess the blood pressure levels of patients who suffer from either hypotension or hypertension.

This is the most frequent reason for improper use in self-administered blood pressure measurement. If circulation has not yet adjusted to a steady resting state, the systolic and diastolic blood pressure and pulse rate will deviate relative to the resting value. The user will register inaccurate readings while these variations occur! A resting time of at least 5 minutes should therefore be chosen before commencing blood pressure measurement.

Deliberate movements , muscle activities , coughing , sneezing and psychological demands such as speaking, listening and watching (e.g. TV) may lead to false readings when measuring blood pressure. Measurements should therefore be carried out under conditions of complete rest and without any distraction.

Cardiac rhythm disorders can cause inaccurate readings or may result in measurement failure. These cardiac rhythm disorders may occur without the self-user being aware of them.

Repeat measurements should be taken whenever Self- administered blood pressure measurements are carried out, since single readings may vary due to a broad number of reasons. For this reason, clinical blood pressure measurements are usually carried out with repeat measurements. The mean value of artifact-free results represents a very reliable estimation of the patient's arterial blood pressure.