Real problems: a layered approach to constructing a patient simulation.

We propose and have implemented a program, called "Real Problems", for the authoring of simulated patient encounters. This program uses a layered database approach to separate the unchanging sections of the program from the more patient-specific sections, so as to increase the speed of authoring. The user's interest is maintained through the use of graphics, sound and extensive feedback.

Safety of dipyridamole-thallium imaging in high risk patients with known or suspected coronary artery disease.

The effects of an oral dipyridamole suspension were studied in 400 consecutive patients to determine if certain subsets of patients were at greater risk of suffering major complications. Most patients (69%) experienced at least one side effect. Severe chest pain, severe hypotension, and severe dyspnea occurred in 9%, 2.5%, and 0.3% of patients respectively. Two patients were hospitalized for persistent chest pain but none suffered a myocardial infarction, malignant ventricular arrhythmia, or death. The test was found to be safe for patients over 70 yr old. Severe dyspnea was rare even among patients with lung disease who were withdrawn from theophylline prior to testing. Patients with three-vessel coronary artery disease were more likely to experience severe chest pain and those with significant left ventricular dysfunction were more likely to develop severe hypotension. In 99.5% of patients, side effects were promptly reversed by aminophylline. Dipyridamole-thallium imaging has an acceptable safety profile for a wide variety of patients, including those with severe coronary disease and/or left ventricular dysfunction.