Microprocessor-Based Blood Gas Analyzer

An automatic blood gas analyzer based on the Intel 8080 microprocessor has been designed, built, and is in use in a clinical laboratory. Commercially available blood gas electrodes and amplifiers serve as the input devices. The microprocessor system, utilizing less than 2 1/4K words of memory stored in PROM, consists of a set of subroutines and utility programs which utilize a floating point math package which contains, besides the four basic functions, log10 X and 10x functions. The subroutines enable the microprocessor to monitor the reaction in the electrode chamber, compensate the measured blood gas values for abnormal body temperature, and calculate three additional parameters: HCO-3 concentration, base excess, and percent O2 saturation of hemoglobin. The only steps left to the medical personnel are to clean and calibrate the electrodes, introduce the blood into the electrode chambers, and distribute the printed results.