The third industrial revolution has radically impacted the transformation of hospitals. Through the adoption of key digital technologies, hospitals have become more accessible, flexible, organised, responsive and able to deliver more personalised care. The digitalisation of patient health records, one of the most remarkable achievements to date in healthcare management, has enabled new opportunities, including the idea of hospitals evolving to become artificially intelligent. In parallel, the adoption of electronic and mobile internet technologies in hospitals has introduced new structural concepts, seeing a variety of terms blossom such as 'smart', 'intelligent', 'green' and 'liquid'. Now in the early fourth industrial revolution, driven by AI and internet-of-things technologies, this article unveils a new concept adapted to the upcoming era.

As internet of things (IoT) technologies are increasingly adopted by healthcare and hospitals, new opportunities are emerging to transform patient pathways and achieve efficient delivery of care. This implemented project follows the drivers and requirements of industry 4.0, based on surgical process analysis and optimisation using IoT technology, with the goal of creating '4.0 hospitals'.Our study presents the implementation of a novel IoT application, aiming to give support to multidisciplinary surgical teams through the optimisation of patient pathways to facilitate the surgical process. The implemented solution is based on real-time location systems (RTLS) technology, a subgroup within IoT, and it originated through the hospital needing to address the sudden surge of surgical elective care demand. The solution also enhances patient safety, facilitates quality of care by increasing communication and reduces costs. This IoT tool has facilitated the increase of theatre utilisation from 70.02% to 82.5% in 2 years, which has translated into an increase of surgical activity capacity, with an impact on reducing the waiting list.

The energy consumed by surgery units constitutes a staggering part of the overall healthcare carbon footprint. Partly due to the demanding climate conditions necessitated by operating theatres (OTs), energy is also wasted because of poorly managed heating, ventilation and air-conditioning systems (HVACs) that consume up to 57% of the total energy used in a hospital. With their goal of optimising OTs' performance and reducing patient waiting lists, heads of surgery units worldwide do not dare to risk cancelling scheduled surgery because of problems with the OT environment conditions (ie temperature, humidity, pressure). Current solutions are monolithic, complex and completely disconnected from healthcare logic, failing to take into account the idiosyncrasy of hospitals. This article presents an innovation that uses real-time patient flow data to automate and optimise the OT's climate conditions.