Biomedical subjects

P Nohama

Publications and source records attributed to P Nohama.

4 recordsLinked to original sources

PubMed2000

Comparison of two knowledge bases on the detection of drug-drug interactions.

This paper describes a drug ordering decision support system that helps with the prevention of adverse drug events by detecting drug-drug interactions in drug orders. The architecture of the system was devised in order to facilitate its use attached to physician order entry systems. The described model focuses in issues related to knowledge base maintenance and integration with external systems. Finally, a retrospective study was performed. Two knowledge bases, developed by different academic centers, were used to detect drug-drug interactions in a dataset with 37,237 drug prescriptions. The study concludes that the proposed knowledge base architecture enables content from other knowledge sources to be easily transferred and adapted to its structure. The study also suggests a method that can be used on the evaluation and refinement of the content of drug knowledge bases.

Artificial Intelligence↗

PubMed2000

Design, implementation and evaluation of a clinical decision support system to prevent adverse drug events.

Adverse drug events are known to be a major health problem worldwide. It is estimated that the annual costs related to these events in the United States are greater than the total costs with cardiovascular disease care. Decision support systems that assist drug ordering have demonstrated to be a powerful tool to prevent prescription errors and adverse drug events. On the other hand, some issues related to the development, implementation, configuration, and evaluation of these decision support systems still need further research. This paper presents the development and evaluation of a decision support system prototype that helps with the prevention of adverse drug events by detecting drug-drug interactions in drug orders. The structure of the system tries to solve some of the problems described by the literature, such as integration with hospital information systems, adaptability to local needs, and knowledge base maintenance. The proposed model has shown to be an effective method for representing drug-drug interactions. The prototype was evaluated by a retrospective study using a dataset with 37.237 prescriptions. The system was able to detect 10.044 (27.0%) orders containing one or more drug-drug interactions. Among these interactions, 6.4% had high severity. In a future study, it is intended to apply the developed system in a real-time on-line environment, evaluating the benefits achieved in terms of improvement in medical practice and patient outcomes.

Adverse Drug Reaction Reporting Systems↗

PubMed1996

A solution for linearity, stability and frequency bandwidth in PAM electrocutaneous stimulators' isolation interface.

This paper introduces a novel method to isolate low-level from high-voltage circuits and/or channels of PAM electrocutaneous stimulators in neuromuscular electrical stimulation (NMES). The method avoids problems of linearity and polarization stability of optocouplers and narrow bandwidth of isolation amplifiers. Its main parameters are: carrier frequency of rectangular pulses up to 1 MHz and maximum modulating signal (elliptical or triangular envelopes) of 50 kHz. The circuit has low drift, high-voltage isolation, low-power consumption, requires few components, is battery-operated and ideal for microcomputer interface-based applications.

Analog-Digital Conversion↗

PubMed1995

Electrotactile stimulator for artificial proprioception.

With the goal of investigating artificial proprioception elicited by electrical stimulation, we have developed a tactile phi phenomenon-based stimulator. This two-channel microprocessed pulse amplitude modulation system generates two different envelope waveforms (triangular and elliptical) and allows programming and visualizing of its main parameters: pulse with (0.1-10 ms), pulse frequency (0.1-10 kHz), modulation frequency (0.3-10 Hz), current intensity (up to 20 mA), and the amplitude modulation index (0-100%). In vivo experiments with 5 normal persons have shown that it is possible to elicit a moving fused phantom image with good resolution. A triangular envelope is good for straight line sensations while the elliptical one is more comfortable and has better resolution for all kinds of moving images.

Biofeedback, Psychology↗