Envirolieve final phase development, regulatory approval and clinical evaluation: reducing the carbon impact of Entonox through patient-centred innovation.

This application will support the final steps in the regulatory process and successful adoption into practice of a novel medical device, which has the potential to be the single most impactful intervention supporting the NHS's commitment to reaching NetZero carbon emissions by 2045. Background Anaesthetic gases are the largest contributor to the NHS carbon impact of any single medical intervention - accounting for 5% of the total footprint. Nitrous oxide (N2O) is the most harmful single agent in current use: it has 298 times the carbon impact of carbon-dioxide and remains in the atmosphere for over 100 years. Occupational exposure is also a risk to staff safety. In the NHS N2O is predominantly used to provide pain and anxiety relief in the form of a pre-mixed 50/50 combination of N2O and oxygen, known as Entonox® or "gas and air". Entonox® is used in over 1million patient episodes annually in the NHS alone. Particularly in maternity care, there are no reasonable alternatives; therefore a technological solution to N2O emissions is required. We have developed such a solution – Envirolieve® – a mechanical device which uses a reuse principle to recycle gas exhaled by patients, reducing both N2O emissions and occupational exposure risk. Working with clinicians and public, we have developed Envirolieve to Technology Readiness Level-7 (TRL7), with confirmation in preclinical tests that it is safe and reduces Entonox® emissions by 50%. Over the next six months (pre-award) we will complete Phase I clinical testing, using the final prototype of the inner mechanical workings of the device. The remaining steps for product development are design of the outer housing and patient-specific disposables, which require co-design with patient and clinician engagement. The proposed research programme will complete the final design process, complete the steps required to gain regulatory approval, demonstrate Envirolieve s effectiveness and cost-effectiveness in real-world settings, and develop and implement a commercialisation plan. Aims To complete pre-CA testing and regulatory submissions To facilitate rapid adoption of the CA-marked Envirolieve® device into clinical practice in the NHS Methods Aim 1: Using usability engineering principles, we will iteratively co-design the outer housing and disposables, user interface and supporting materials with patients, public and clinicians. We will then batch manufacture a limited number of these components to complete the final prototype devices. We will then undertake summative human factors/usability testing according to MHRA requirements and the designated standards. Following this, we will submit our application for regulatory approval for a UKCA mark. Aim 2: We will deliver a post-CA Phase II clinical study to evaluate patient acceptability and satisfaction, and staff occupational exposure and satisfaction, across three different use cases (maternity, emergency department and endoscopy). We will undertake health economic and environmental benefit evaluations. Finally, we will develop and implement a commercialisation plan in conjunction with commercial, NHS, professional and public stakeholders. Timelines and Impact: 3-year programme of work; by the end, we will have reached TRL9, and have the data and infrastructure required to support rapid adoption into the NHS.