Detecting Abnormalities On Displays Of Patient Information

This project tested a new physiological information display that aims to improve a clinician’s ability to detect vital sign abnormalities before those abnormalities trigger an alarm. The configural display integrates information about heart rate, blood pressure, and blood oxygen saturation into a visual representation of the patient’s current state relative to alarm and “pre-alarm” thresholds. Eight participants were asked to monitor patient displays for six different types of emergency events under three display configurations (numerical, configural, and both) and two levels of cognitive load. The numerical display showed color-coded numerical values of each of the three patient parameters. Emergency events involved abnormal values of heart rate, blood pressure, and blood oxygen saturation that occurred approximately every thirty seconds during six ten-minute patient monitoring blocks. Cognitive load was manipulated using an N-back task with two levels (N = 1 and N = 2). Emergency event detection was faster when both the configural display and numerical display were present than when only the numerical display was present. Furthermore, a combined display showing both the numerical and configural information required the fewest number of alarms to facilitate correct detection of emergency events. In addition, reaction times to emergency events were slower in the high cognitive load condition than in the low cognitive load condition. These results suggest that the combination of numerical and configural displays has the potential to reduce the number of threshold alarms and reduce the time it takes clinicians to respond to emergency events.