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Beale R, Rosendo JB, Bergeles C, Beverly A, Camporota L, Castrejón-Pita AA, Crockett DC, Cronin JN, Denison T, East S, Edwardes C, Farmery AD, Fele F, Fisk J, Fuenteslópez CV, Garstka M, Goulart P, Heaysman C, Hussain A, Jha P, Kempf I, Kumar AS, Möslein A, Orr ACJ, Ourselin S, Salisbury D, Seneci C, Staruch R, Steel H, Thompson M, Tran MC, Vitiello V, Xochicale M, Zhou F, Formenti F, Kirk T. OxVent: Design and evaluation of a rapidly-manufactured Covid-19 ventilator. EBioMedicine 2022; 76:103868. [PMID: 35172957 PMCID: PMC8842095 DOI: 10.1016/j.ebiom.2022.103868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/08/2021] [Accepted: 01/21/2022] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND The manufacturing of any standard mechanical ventilator cannot rapidly be upscaled to several thousand units per week, largely due to supply chain limitations. The aim of this study was to design, verify and perform a pre-clinical evaluation of a mechanical ventilator based on components not required for standard ventilators, and that met the specifications provided by the Medicines and Healthcare Products Regulatory Agency (MHRA) for rapidly-manufactured ventilator systems (RMVS). METHODS The design utilises closed-loop negative feedback control, with real-time monitoring and alarms. Using a standard test lung, we determined the difference between delivered and target tidal volume (VT) at respiratory rates between 20 and 29 breaths per minute, and the ventilator's ability to deliver consistent VT during continuous operation for >14 days (RMVS specification). Additionally, four anaesthetised domestic pigs (3 male-1 female) were studied before and after lung injury to provide evidence of the ventilator's functionality, and ability to support spontaneous breathing. FINDINGS Continuous operation lasted 23 days, when the greatest difference between delivered and target VT was 10% at inspiratory flow rates >825 mL/s. In the pre-clinical evaluation, the VT difference was -1 (-90 to 88) mL [mean (LoA)], and positive end-expiratory pressure (PEEP) difference was -2 (-8 to 4) cmH2O. VT delivery being triggered by pressures below PEEP demonstrated spontaneous ventilation support. INTERPRETATION The mechanical ventilator presented meets the MHRA therapy standards for RMVS and, being based on largely available components, can be manufactured at scale. FUNDING Work supported by Wellcome/EPSRC Centre for Medical Engineering,King's Together Fund and Oxford University.
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Affiliation(s)
- Richard Beale
- Centre for Human and Applied Physiological Sciences, King's College London, UK; Intensive Care Unit, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | | | - Christos Bergeles
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Anair Beverly
- Department of Engineering Science, University of Oxford, UK
| | - Luigi Camporota
- Centre for Human and Applied Physiological Sciences, King's College London, UK; Intensive Care Unit, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | | | - Douglas C Crockett
- Nuffield Department of Clinical Neurosciences, University of Oxford, UK; Milton Keynes University Hospital NHS Foundation Trust, Milton Keynes, UK
| | - John N Cronin
- Centre for Human and Applied Physiological Sciences, King's College London, UK; Department of Anaesthesia, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Timothy Denison
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, UK
| | - Sebastian East
- Department of Engineering Science, University of Oxford, UK
| | | | - Andrew D Farmery
- Nuffield Department of Clinical Neurosciences, University of Oxford, UK
| | - Filiberto Fele
- Department of Engineering Science, University of Oxford, UK
| | - James Fisk
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, UK
| | - Carla V Fuenteslópez
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, UK
| | | | - Paul Goulart
- Department of Engineering Science, University of Oxford, UK
| | - Clare Heaysman
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | | | - Prashant Jha
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Idris Kempf
- Department of Engineering Science, University of Oxford, UK
| | | | - Annika Möslein
- Department of Engineering Science, University of Oxford, UK
| | - Andrew C J Orr
- Department of Engineering Science, University of Oxford, UK
| | - Sebastien Ourselin
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - David Salisbury
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, UK
| | - Carlo Seneci
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Robert Staruch
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, UK; Nuffield Department of Orthopaedic, Rheumatology and Musculoskeletal Sciences, University of Oxford, UK; The Academic Department of Military Surgery and Trauma, Birmingham, UK
| | - Harrison Steel
- Department of Engineering Science, University of Oxford, UK
| | - Mark Thompson
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, UK
| | - Minh C Tran
- Department of Engineering Science, University of Oxford, UK; Nuffield Department of Clinical Neurosciences, University of Oxford, UK
| | - Valentina Vitiello
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Miguel Xochicale
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Feibiao Zhou
- Department of Engineering Science, University of Oxford, UK
| | - Federico Formenti
- Centre for Human and Applied Physiological Sciences, King's College London, UK; Nuffield Department of Clinical Neurosciences, University of Oxford, UK; Department of Biomechanics, University of Nebraska Omaha, Omaha, NE, USA.
| | - Thomas Kirk
- Nuffield Department of Clinical Neurosciences, University of Oxford, UK; Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, UK.
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