"I want to treat the patient, not the alarm": User image mismatch in Anesthesia alarm design.

Sammanfattning: Although the development of physiologic monitors has improved the safety of patients undergoing anesthesia, a growing body of literature suggests that alarms function sub-optimally in supporting the human operator. A principle of cognitive systems engineering is that there is an image of the user “built in” to the design of any machine used in a joint cognitive (man-machine) system. This study explored the existence of a mismatch between the image of the user built into the anesthesia monitor alarm (machine-embedded image) and the anesthesiologist’s own image of himself (user-described image) and whether any such user image mismatch contributed to coordination failure between anesthesiologist and alarm. The Participant Guide for the Carescape B850 Anesthesia monitor was analyzed to define machine-embedded images. Fourteen anesthesiologists were interviewed to explore user-described images and man-machine coordination. User image mismatch was observed in each of three alarm behaviours studied. Furthermore, user image mismatch was found to be related, as symptom of and contributor to the instances of coordination failure described by interviewees.