Patients with dementia often suffer from stress episodes that escalate to anxiety. This paper presents a feasibility study of using environmental smart microphones to detect anxiety in patients with dementia. It is based on the identified auditory manifestations of anxiety. To have a better understanding of the anxiety manifestations in patients with dementia, 70 diagnosed patients were observed in-situ and 4 caregivers were interviewed. The design of an environmental smart microphone called AnxiCare has been developed and it is introduced. Feasibility interviews regarding the use of AnxiCare were conducted with caregivers at a care residence in Spain. Results from the observations, interviews and a preliminary validation are presented.