Use case: Silent Hospitals trial

The Silent Hospital concept is an emerging model of healthcare redesign that seeks to ensure hospital spaces such as wards are not just functional but therapeutic through the considered avoidance of and reduction in anthropogenic noise. Noise may be generated by technological and non-technological sources, for example medical equipment and nurse call alerts, and footsteps and conversations respectively. 

Despite globally recognised guidelines for noise exposure, studies have demonstrated that, within industrialised countries, noise pollution in hospitals now commonly exceeds recognised standards. To investigate this a trial at Linden Lodge to measure noise pollution levels and to evaluate the impact of this on staff.

For more details on the research, studies and World Health Organisation guidelines on noise pollution please see Appendix A 'Silent Hospital summary report' and Appendix B 'Silent Hospitals Project Overview' from the full report at Lessons Learned from IoT Implementation - Networks & Connectivity Transformation - Frontline Capabilities (FutureNHS login required).

To provide justification for these trials to go ahead the trust needed to gather evidence to demonstrate current noise levels. This was done by extracting log data from the nurse call system, to understand the frequency of these alarms, and a mobile application was used to assess noise levels during alarm calls.

For the trial the trust installed wireless noise sensors around Linden Lodge and over the course of six months found that the noise levels measured were never below the recommended WHO guidelines. Interrogation of the nurse calls demonstrated a direct correlation between the number of calls and noise levels recorded, in line with other work and research on alarm fatigue in nurses, including Alarm Fatigue - Making Healthcare Safer III: A Critical Analysis of Existing and Emerging Patient Safety Practices.

Network infrastructure

Linden Lodge uses Cisco infrastructure and architecture for its networking and Cisco Access Points. Using Bluetooth Low Energy (BLE), they act as the IoT gateways. Cisco Spaces is used to provide analytics and visibility of the network and IoT devices connected via the Wi-Fi Access Points (APs). 

Additional system implementations

To connect the room controllers to the Building Management System (BMS) the trust uses additional BMS devices, which connect to the access switches via cabling.

For room-based controls a segregated network was established that had its connectivity controlled by perimeter Firewalls. This ensured only very limited connectivity could be established between these devices and the internal trust network. Access was granted for Dynamic Host Configuration Protocol (DHCP) IP address and Domain Name System (DNS) access. All other access was blocked but could be modified to be allowed if and when required.

A lesson learned from this implementation is that segmentation of outbound addresses (separating PAT addresses from LAN ranges) for IoT range allows for separation of networks when a cyber threat is detected, allowing easier investigation and remediation.