Colin BP-S510, Руководство по эксплуатации

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General
The monitor uses pulse oximetry to measure functional oxygen saturation in the blood.
Because a measurement of SpO
2
is dependent upon light from the SpO
2
sensor,
excessive ambient light can interfere with this measurement. SpO
2
and Pulse rate is
updated every second. This monitor measures functional saturation - oxygenated
hemoglobin expressed as a percentage of the hemoglobin that can transport oxygen. It
does not detect significant amounts of dysfunctional hemoglobin, such as
carboxyhemoglobin or mehtemoglobin.
Functional versus Fractional Saturation
This monitor measures functional saturation — oxygenated hemoglobin expressed as a
percentage of the hemoglobin that can transport oxygen. It does not detect significant
amounts of dysfunctional hemoglobin, such as carboxyhemoglobin or methemoglobin. In
contrast, hemoximeters such as the IL482 report fractional saturation — oxygenated
hemoglobin expressed as a percentage of all measured hemoglobin, including measured
dysfunctional hemoglobin. To compare functional saturation measurements to those from
an instrument that measures fractional saturation, fractional measurements must be
converted as follows:
functional saturation = fractional saturation
100 – (%carboxyhemo %methemoglobin)
Measured versus Calculated Saturation
When saturation is calculated from a blood gas partial pressure of oxygen (PO2), the
calculated value may differ from the SpO
2
measurement of the monitor. This usually
occurs because the calculated saturation was not appropriately corrected for the effects of
variables that shift the relationship between PO2 and pH, temperature, the partial
pressure of carbon dioxide (PCO
2
), 2, 3-DPG, and fetal hemoglobin.
Automatic Calibration
Because light absorption by hemoglobin is wavelength dependent and because the mean
wavelength of LEDs varies, an oximeter must know the mean wavelength of the
OXIMAX
sensor’s red LED to accurately measure SpO
2
. The wavelength range of the light emitted
are near 660 nm and 890 nm with the energy not exceeding 15 mW. During monitoring,
the instrument’s software selects coefficients that are appropriate for the wavelength of
that individual sensor’s red LED; these coefficients are then used to determine SpO
2
.
Additionally, to compensate for differences in tissue thickness, the light intensity of the
sensor’s LEDs is adjusted automatically.
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