Schiller Argus VCM Mode D'emploi page 51

ARGUS VCM
Functional versus Fractional Saturation Functional versus Fractional Saturation
This monitor measures functional saturation — oxygenated hemoglobin expressed as a This monitor measures functional saturation — oxygenated hemoglobin expressed as a
percentage of the hemoglobin that can transport oxygen. It does not detect significant percentage of the hemoglobin that can transport oxygen. It does not detect significant
amounts of dysfunctional hemoglobin, such as carboxyhemoglobin or methemoglobin. In amounts of dysfunctional hemoglobin, such as carboxyhemoglobin or methemoglobin. In
contrast, hemoximeters such as the IL482 report fractional saturation — oxygenated contrast, hemoximeters such as the IL482 report fractional saturation — oxygenated
hemoglobin expressed as a percentage of all measured hemoglobin, including measured hemoglobin expressed as a percentage of all measured hemoglobin, including measured
dysfunctional hemoglobin. To compare functional saturation measurements to those from an dysfunctional hemoglobin. To compare functional saturation measurements to those from an
instrument that measures fractional saturation, fractional measurements must be converted instrument that measures fractional saturation, fractional measurements must be converted
as follows: as follows:
functional saturation = functional saturation =
Measured versus Calculated Saturation Measured versus Calculated Saturation
When saturation is calculated from a blood gas partial pressure of oxygen (PO2), the When saturation is calculated from a blood gas partial pressure of oxygen (PO2), the
calculated value may differ from the SpO2 measurement of the monitor. This usually occurs calculated value may differ from the SpO2 measurement of the monitor. This usually occurs
because the calculated saturation was not appropriately corrected for the effects of variables 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 that shift the relationship between PO2 and pH, temperature, the partial pressure of carbon
dioxide (PCO2), 2, 3-DPG, and fetal hemoglobin. dioxide (PCO2), 2, 3-DPG, and fetal hemoglobin.
Automatic Calibration Automatic Calibration
Because light absorption by hemoglobin is wavelength dependent and because the mean 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 wavelength of LEDs varies, an oximeter must know the mean wavelength of the OXIMAX
sensor's red LED to accurately measure SpO2. The wavelength range of the light emitted are sensor's red LED to accurately measure SpO2. The wavelength range of the light emitted are
near 660 nm and 890 nm with the energy not exceeding 15 mW. During monitoring, the 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 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 SpO2. individual sensor's red LED; these coefficients are then used to determine SpO2.
Additionally, to compensate for differences in tissue thickness, the light intensity of the Additionally, to compensate for differences in tissue thickness, the light intensity of the
sensor's LEDs is adjusted automatically. sensor's LEDs is adjusted automatically.
Adjusting Pulse Tone Volume from SpO2 signal Adjusting Pulse Tone Volume from SpO2 signal
For the setting the pulse tone volume, you may refer to page 30, of this manual. For the setting the pulse tone volume, you may refer to page 30, of this manual.
1. Press the Mode button 4 times until the Pulse Tone Volume setting indicator and 1. Press the Mode button 4 times until the Pulse Tone Volume setting indicator and
current pulse tone volume are displayed. current pulse tone volume are displayed.
2. Select a level of pulse tone volume between 0 and 8, using the Up/Down (+/-) 2. Select a level of pulse tone volume between 0 and 8, using the Up/Down (+/-)
selection buttons. selection buttons.
fractional saturation fractional saturation
100 – (%carboxyhemoglobin + %methemoglobin) 100 – (%carboxyhemoglobin + %methemoglobin)
Operator's Manual
ARGUS VCM
SpO /Pulse Rate Monitoring
2
× 100
45