Perfusion Index i ndicator

1 What Perfusion Index indicator is A pulse oximeter is a device that analyzes the rate between oxygenated hemoglobin and reduced hemoglobin as arterial oxygen saturation(SpO2). This difference is measured by the amount of light absorbed through the pulse of when light is transmitted through the finger. On the basis of the measurement principle, a pulse oximeter may show unstable SpO2 value and become unable to make measurement because of the following reasons; Excess noise caused by body movement or outside light ( sunlight).

2 (An indication of such would be that the pulse bar display will fluctuate.) Reduction of peripheral blood current due to arterial constriction or artery blockage With low Perfusion , the amount of light which PD (photo diode) receives may become excessively high or low. The larger the difference of light received by PD, the more accurate the measurement become. On the contrary, when the peripheral Perfusion is low, the mesasurement value becomes unstable (SD becomes large). Also, the peripheral Perfusion could indicate low value due to compression of the part of the finger being measured, incorrect installation of a sensor probe, or body temperature decrease.

3 PIi indicates fluctuation rate of received light with an indicator (PIi ). Especially when measurement time is short, in order to measure SpO2 Perfusion under the appropriate conditions, please observe the PIi. The state of low Perfusion : Perfusion becomes low with peripheral vascular constriction under the following condition; cardiac arrest, shock, arteriosclerosis, temperature decrease of fingers, compression of fingers (non invasive blood pressure measurement etc.), arteriosclerosis obliterans, Buerger's disease(inflammation), Raynaud's disease(vascular constriction), etc.

4 UBIX diplays Perfusion by an easy to understand four step indicator Index (PIi ). P I(%) Formula of Perfusion Index indicator and PIi Perfusion Index i ndicator display 100 difference of amount of light Total amount of light received Perfusion Index indicator (%) = Vasoconstriction The light received increases because it is easy to transmit light. The relationship between pulse beat and light received by PD Time Light received by PD Vascular dilation The light received decreases because it is difficult to transmit light.

5 Difference of the amount of light receivProbe and the measurement point LED PD Measurement point (finger) Perfusion Index i ndicator Relationship between difference of amount of light and PIi display Time Light received by PD Difference(Moderate) 2 4 Time Light received by PD Difference (small) 2 Total amount of light received 100 Time Difference(sufficient) more than 4% Light received by PD Total amount of light received 100 Total amount of light received 100