Elastic recoil pressure, pleural pressure and pressure pulsation of the heart (PHRT) control the expired flow from a small lung unit. Variability in each trait may affect the expirate. The same (SDPV) or different (DDPV) regional distribution of P-V characteristics, regional effects of PHRT-affected (O) and non-affected units (N) and regional differences in pleural pressure, were incorporated into a computer model. Output acceptability was judged by the alveolar slope of the N2 washout, cardiogenic oscillations (CO) and the phase shift between PHRT and CO. Can SDPV be in both O and N units? What causes CO and phase shift? With SDPV in O and N units, CO were negligibly small. The incorporation of the pleural pressure difference did not fulfill the three criteria, which were met when there was DDPV in the N and O units. We conclude that the distribution of P-V characteristics changes with the distance from a pulsating artery, and only DDPV, and not different time constants or pleural pressure difference, can explain CO.

Blood Pressure↗

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SMR (simulating medical reasoning): an expert shell for non-AI experts.

SMR is an expert system shell designed to put the tools for knowledge acquisition directly into the hands of the domain expert. Since the knowledge base is represented as free text within a simplified syntactic structure, it is intelligible to anyone familiar with medical terminology. The knowledge base includes the rules for inference making as well as data groupings and protocols to facilitate case recording. In this paper, SMR is presented from the expert's point of view, describing the rule syntax and procedures for formulating the required diagnostic or therapeutic knowledge in the chosen domain. Similarly, the end-user's application of the system to patient data and the provisions for exploring and explaining the system's conclusions and reasoning processes are detailed. Avoiding tedious and often inane dialog, the user enters all that is known about the patient and receives a report of the system's conclusions and recommendations followed by a list of observations to be made in patient follow-up. An expert system for evaluating the diabetic patient is used to illustrate system operations.

Computer Simulation↗

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A knowledge-based information system for advice in the crisis management of the patient with burns.

A knowledge-based information system that has been designed to be used as an electronic advisor to guide in fluid resuscitation and in the management of the most frequently occurring complications during the first 48 hours after burn injury is described. The system was also developed for training physicians and nurses and may eventually be used for peer review of the management of patients in the burn unit. Ten data screens are used for entry of the administrative data, the clinical background, and the monitored data. The latter include tables for recording fluid therapy and laboratory results. The knowledge base consists of a series of heuristic decision rules that were formulated by a burn care expert and that express the Uppsala fluid resuscitation program to prevent burn shock. The data recorded for a patient are compared with the data in the knowledge base, and the appropriate conclusions are generated. The system's conclusions, the fluid and ventilation prescription, and other required patient management measures are then displayed as a report. The underlying reasoning for each case may be explored by means of the system's explanation facility. The system has been successfully validated by 125 hypothetic cases that represent typical situations of patients with severe burns.

Adult↗

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A new method for differentiating simple intra-abdominal from strangulated small-intestinal obstruction.

We developed a model that aids in the differentiation of simple from strangulated intra-abdominal small-intestinal obstruction and reached an accuracy rate of 97 percent in predicting strangulated obstruction. Fifty-three criteria were analyzed from the records of 229 patients and by the Bayes statistical mode; five statistically significant criteria were identified. Using these, and another 16 criteria that indicated trends, we were able to predict strangulated obstruction with a 97 percent accuracy. Neither laboratory tests nor abdominal roentgenography aided in the diagnosis.

Aged↗

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[Histological and histochemical study of guinea pig adrenal glands treated with ascaridian extracts].

Explore the source record for details and available documents.

Acid Phosphatase↗

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Cardiovascular monitoring in the medical intensive care unit.

The need for and development of computer-based monitoring in medical intensive care are discussed. The critical care ward system at the University of Southern California's Center for the Critically Ill is described. Basic monitoring routines include measurement of heart rate; arterial, venous, and pulmonary pressures; core and peripheral temperature; and urine output. Other application programs handle cardiac output determinations, laboratory tests, narrative data entry, and process control. Data retrieval provides for tabular, textual, and graphic displays both at the bedside and in hard copy, as well as data printouts for research purposes. Computer control covers the vascular interface, automated pressure calibration, peristaltic pumps for fluid infusion and blood sampling, and urine collection and disposal. Using automated fluid challenge as a prototype, servo operations should be extended to mechanical ventilation and fluid therapy.

Blood Chemical Analysis↗