Operator's Manual

Rad-97 Chapter 1: Technology Overview
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(blood with oxidized hemoglobin) and blood plasma constituents differ in their
absorption of visible and infrared light (using spectrophotometry).
2. The amount of arterial blood in tissue changes with pulse
(photoplethysmography). Therefore, the amount of light absorbed by the varying
quantities of arterial blood changes as well.
The Rad-97 uses a multi-wavelength sensor to distinguish between oxygenated blood,
deoxygenated blood, blood with carbon monoxide, oxidized blood and blood plasma.
The Rad-97 utilizes a sensor with various light-emitting diodes (LEDs) that pass light through
the site to a diode (detector). Signal data is obtained by passing various visible and infrared
lights (LEDs, 500 to 1400nm) through a capillary bed (for example, a fingertip, a hand, a foot)
and measuring changes in light absorption during the blood pulsatile cycle. This information
may be useful to clinicians. The maximum radiant power of the strongest light is rated at ≤ 25
mW. The detector receives the light, converts it into an electronic signal and sends it to the
Rad-97 for calculation.
1. Light Emitting Diodes (LEDs)
(7 + wavelengths)
2. Detector
Once Rad-97 receives the signal from the sensor, it utilizes proprietary algorithms to
calculate the patient’s functional oxygen saturation (SpO
2
[%]), blood levels of
carboxyhemoglobin saturation (SpCO [%]), methemoglobin saturation (SpMet [%]), total
hemoglobin concentration (SpHb [g/dL]) and pulse rate (PR). The SpCO, SpMet and SpHb
measurements rely on a multi-wavelength calibration equation to quantify the percentage of
carbon monoxide and methemoglobin and the concentration of total hemoglobin in arterial
blood. Maximum skin-sensor interface temperature was tested to be less than 41º C (106º F)