User's Manual

Rad-87 Pulse CO-Oximeter Operator’s Manual
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Overview
Signal Processing
The digital signal produced by the acquisition system is converted into a measurement that
corresponds to the respiratory parameter of interest. As shown in the figure on the previous page,
this can be performed by, for example, determining the digital signal envelope or outline which in
turn may be utilized to determine the respiratory rate. In this way, a real-time, continuous breath
rate parameter can be obtained and displayed on a monitor which, in many cases, may be real-
time and continuous.
The respiratory cycle envelope signal processing principle is similar to methods that sample
airway gases and subsequently determine a respiratory rate.
[1] A.R.A. Sovijärvi, F. Dalmasso, J. Vanderschool, L.P. Malmberg, G. Righini, S.A.T. Stoneman. Definition of terms for
applications of respiratory sounds. Eur Respir Rev 2000; 10:77, 597-610.
[2] Z. Moussavi. Fundamentals of respiratory sounds analysis. Synthesis lectures on biomedical engineering #8. Morgan
& Claypool Publishers, 2006.
[3] Olsen, et al. Mechanisms of lung sound generation. Semin Respir Med 1985; 6: 171-179.
[4] Pastercamp H, Kraman SS, Wodicka GR. Respiratory sounds – Advances beyond the stethoscope. Am J Respir Crit
Care Med 1977; 156: 974-987.
[5] Gavriely N, Cugell DW. Airflow effects on amplitude and spectral content of normal breath sounds. J Appl Physiol
1996; 80: 5-13.
[6] Gavrieli N, Palti Y, Alroy G. Spectral characteristics of normal breath sounds. J Appl Physiol 1981; 50: 307-314.
FastSat
FastSat enables rapid tracking of arterial oxygen saturation changes. Arterial oxygen saturation
data is averaged using pulse oximeter averaging algorithms to smooth the trend. When the Rad-
87 is set to FastSat “On”, the averaging algorithm evaluates all the saturation values providing
an averaged saturation value that is a better representation of the patient’s current oxygenation
status. With FastSat, the averaging time is dependent on the input signal.