Circulation measurement with Finapres®: How does it work?
Your circulation is a dynamic system: With pressure blood flows from the heart via your arteries into the body and via your veins back to the heart. Your blood vessels have to oppose the blood flow: the vascular resistance.
Vascular resistance depends on your blood pressure and blood flow. If you compare this hydraulic system with a bellows, then the blood pressure is the tension in the bellows and the blood flow is the air coming out the front. Both of these parameters are important for assessing vascular resistance and thus the condition of your circulatory system. The vascular resistance regulates both the pressure control circuit, which is important for a balanced blood distribution in the body, and the temperature control circuit, which ensures a stable heat distribution in the body.
In current practice, only blood pressure is measured almost exclusively, for example in the evaluation of high blood pressure. This results in an incomplete picture of a person’s cardiovascular system, which can often lead to incorrect treatment and side effects. An optimal therapy setting is only possible if both parameters – blood pressure and blood flow – have been completely recorded and understood beforehand.
Blood flow can be measured, for example, during a cardiac catheter examination, which, however, is associated with an invasive procedure. For some years now, however, there has been a non-invasive and therefore bloodless method which is considered a scientifically validated gold standard: Finapres®. With this so-called photoplethysmographic procedure, a plastic ring (cuff) is placed around your middle finger. While pressure is exerted on this cuff, a light sensor measures how much blood flows through your finger. The device uses this information to determine your blood pressure and blood flow.
In addition, further values are measured that are important for assessing the circulatory system: the baroreceptor sensitivity and the heart rate variability (HRV). The examination can be performed standing, sitting or lying with you, which allows us a very detailed analysis. Even under stress, in combination with a stress echocardiography, we can perform the holistic circulation measurement. It is completed by an obligatory simple temperature measurement.
For a modern and individual interpretation of the circulation, 20-25 individual measured values must be considered and evaluated integratively. This requires a lot of experience and good scientific basic knowledge of the treating physician. On the basis of our extensive experience in intensive care units and cardiac catheterisation laboratories, we have been carrying out over 2,400 measurements annually in Cardiopraxis since 2011 using the Finapres® method. It is also impressive for us again and again how many health-relevant findings we can gain for the individual through the consistent use of this method.