Computerized medical reasoning in diagnosis and treatment of acid-base disorders.

A system is described for aiding the clinician in the management of acid-base disorders. The medical knowledge required for interpretation of blood gas measurements, etiologic diagnosis, and treatment selection for acid-base disorders is structured into decision pathways consisting of a series of inferences. Each inference is defined by a medical logic module which specifies the different combinations of criteria, patient data and/or previously confirmed inferences, sufficient for confirming or rejecting the inference. A method is provided for converting numerical observations to the appropriate logical statement used in the modules. Patient data are compared to the medical logic and a status report lists the input data, acid-base diagnosis, and the suggested therapy. After initial testing on patient data, the medical logic was updated to express the medical policy of our clinical specialists. The system was applied to 54 patients and the system's conclusions were in full agreement with our staff in 93% of the cases, and in partial agreement in the other cases. The modular structure of the system's medical knowledge allows full expression of all the nuances of medical policy in our unit and facilitates updating to encompass the latest developments in acid-base management. The system can be integrated readily into existing computerized patient monitoring systems.