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Patient-Maintained Sedation: The anxiety of undergoing surgery while conscious

Unit(s) of assessment: Psychology, Psychiatry and Neuroscience

Research theme: Medical Technologies and Advanced Materials

School: School of Science and Technology


The anxiety of undergoing surgery while conscious

Large numbers of patients undergo surgery or other medical procedures while awake, both in the UK and around the world. This can understandably cause high levels of anxiety. However, a substantial body of evidence shows patient-maintained sedation to be superior to traditional physician-controlled regimes.

Addressing the Challenge

Empowering patients to safely control their own sedation within the operating theatre

Researchers at Nottingham Trent University (NTU) are developing an advanced prototype patient-maintained sedation device (PMSD) for clinical trial. Designed to administer an infusion of propofol, it is hoped the device will meet clinical needs and be adopted into sedation practice.

The project requires multidisciplinary medical research, including the design and testing of medical devices, hardware, software, and user interfaces. This project was funded by the NIHR Invention for Innovation Programme (i4i). The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.


Combining public and private expertise

The project is led by external partners from Nottingham University Hospitals NHS Trust. These include Dr Nigel Bedforth, Consultant Anaesthetist and project lead; Dr David Hewson, Clinical Assistant Professor; and Dr Jonathan Hardman, Professor and Consultant in Anaesthesia.

Professor Philip Breedon leads on the project for NTU, focusing on user interface development with support from Dr James Sprinks, the lead software developer. Frank Worcester heads the hardware development and the technical file coordination of the clinical trial system. The sedation pump will be manufactured by B. Braun Medical Ltd.

"The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health, UK. We are grateful to the anaesthetists of Nottingham University Hospitals NHS Trust that took part in and contributed to the design process".

Making a Difference

An improved experience - putting patients in control

The study aims to design a PMSD consisting of an existing infusion pump, a computer-linked control, a newly designed trigger, and a graphical interface. The team needs to develop software to integrate an existing target-controlled infusion (TCI) software algorithm for propofol delivery with a control system that allows patients to change the depth of their own sedation.

The team will have to obtain regulatory approval for the subsequent commercialisation of this new medical device. This requires completing a clinical study to demonstrate the PMSD’s safety and its effectiveness in patients undergoing orthopaedic surgery under regional anaesthesia. The patient-led outcome measures will inform the development of the device, and generate data to drive adoption of the technology. They will also be used to develop a commercialisation strategy for the device.

This technology could benefit a huge number of patients attending hospital for operations or medical investigations. The patient being in control of the device themselves should result in an improved, more patientcentred, overall experience. Key benefits to patients may include faster recovery from surgical and medical procedures and therefore an earlier discharge from hospital.