Progress Report - Automatic Neonate Oxygen Control Project
Robert Farrenkopf
August 30, 2003
Robert Farrenkopf
August 30, 2003
This update includes three supporting photographs. A quick overview of the project will precede the discussion of its present status.
The oxygen concentration delivered to a premature neonate is, at present, manually set by a knob on a ventilator, and is adjusted by a pulmonary therapist in response to the reading on a pulse oximeter measuring the baby’s blood oxygen level. The therapist is an essential part of this activity, but automating this oxygen control should considerably ease the workload of these specialists. Under automatic control, a computer, set by the therapist to the desired blood oxygen level, is tasked to compare that level to the oximeter’s measurement, and to then properly adjust the knob on the ventilator that controls the oxygen concentration.
Deriving a suitable control algorithm, to be imbedded in the computer, is a fairly straightforward software task. By far the greatest implementation challenge involves the communication and interfaces between the computer and the two other necessary hardware items, namely the pulse oximeter and the ventilator. Fortunately, the Masimo pulse oximeter provides, at one-second intervals, an ASCII output field at its serial port; a field that includes the subject’s blood oxygen level. This can then be recovered by connecting a cable to the computer’s serial port, requiring only that appropriate software be written to effect this recovery. While the code developed for this task remains to be verified, this is not regarded as a major problem, as no additional hardware is required.
