An evaluation of a vibro-tactile display prototype for physiological monitoring.

Visual displays and auditory alarms are used to convey information on physiological variables in an operating room. However, the exponential growth in the number of physiological variables and the high probability of false alarms has amplified demands on the clinician's attention. We have extended existing tactile technology to improve situational awareness and produce a practical clinical advisory device. A vibro-tactile display, using two vibrating motors applied to the volar surface of the forearm, was compared to an auditory alarm in a simulated clinical environment. Compared with auditory alarms, the vibro-tactile alarm was as easy to learn and had a better identification rate when used alone or combined with the auditory alarm. Most users preferred the vibro-tactile alarm although the prototype caused some discomfort. Furthermore, a combined vibro-tactile and auditory alarm had reduced accuracy when compared with the vibro-tactile alarm alone. The vibro-tactile modality shows considerable promise for clinical practice but will require further clinical testing and refinement, especially with regard to user comfort.