Noninvasive monitoring and distant assessment of status of the critically injured using real-time analysis of telemetrically transmitted electrocardiogram may revolutionize medical care if devices utilizing new data analysis techniques can be validated that identify physiologic deterioration before changes in conventional vital signs.At present monitoring and diagnosis of critically injured are based on changes in time-averaged means of heart rate and blood pressure in context of visual assessment of the patient.However, changes in heart rate and blood pressure generally do not occur until compensatory mechanisms are exhausted.