Masimo Pronto Pulse CO-Oximeter, Руководство оператора

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Pronto Chapter 1: Technology Overview
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Pulse CO-Oximetry vs. Drawn Whole Blood Measurements
When SpO2 and SpHb measurements obtained from Pronto (noninvasive) are compared to
drawn whole blood (invasive) measurements by blood gas and/or laboratory CO-Oximetry
methods, caution should be taken when evaluating and interpreting the results.
The blood gas and/or laboratory CO-Oximetry measurements may differ from the SpO2 and
SpHb measurements of Pronto. Any comparisons should be simultaneous, meaning the
measurement on the device should be noted at the exact time that blood is drawn.
In the case of SpO2, different results are usually obtained from the arterial blood gas sample
if the calculated measurement is not appropriately corrected for the effects of variables that
shift the relationship between the partial pressure of oxygen (pO2) and saturation, such as:
pH,temperature, the partial pressure of carbon dioxide (pCO2), 2,3-DPG, and fetal
hemoglobin.
In the case of SpHb, variation in hemoglobin measurements may be profound and may be
affected by sampling technique as well as the patient's physiological conditions. Any results
exhibiting inconsistency with the patient's clinical status should be repeated and/or
supplemented with additional test data. As with most hemoglobin tests, a laboratory blood
sample should be analyzed prior to clinical decision making.
High levels of bilirubin may cause erroneous SpO2 and SpHb readings. As blood samples are
usually taken over a period of 20 seconds (the time it takes to draw the blood), a meaningful
comparison can only be achieved if the oxygen saturation, carboxyhemoglobin, and
methemoglobin concentration of the patient are stable and not changing over the period of
time that the blood gas sample is taken. Subsequently, blood gas and laboratory CO-Oximetry
measurements of SpO2 and SpHb may vary with the rapid administration of fluids and in
procedures such as dialysis. Additionally, drawn whole blood testing can be affected by
sample handling methods and time elapsed between blood draw and sample testing.
Measurements with Low Signal IQ should not be compared to laboratory measurements.
General Description for Total Hemoglobin (SpHb)
Pulse CO-Oximetry is a continuous and noninvasive method of measuring the levels of total
hemoglobin (SpHb) in arterial blood. It relies on the same principles of pulse oximetry to
make its SpHb measurement. The measurement is taken by a sensor capable of measuring
SpHb, usually on the fingertip for adults and pediatric patients.
The sensor connects directly to the Pulse CO-Oximeter or with a patient cable. The sensor
collects signal data from the patient and sends it to the device. The device displays the
calculated data as measurement of total hemoglobin concentration.
Successful Monitoring for SpHb
A stable SpHb reading is associated with correct sensor placement, small physiological
changes during the measurement and acceptable levels of arterial perfusion at the
measurement site. Physiological changes at the measurement site are mainly caused by
fluctuations in the oxygen saturation, blood concentration, and perfusion. See Safety
Information, Warnings, and Cautions on page 9.