Functionalised optical fibre multiparameter sensing platform for monitoring during artificial ventilation

Ventilator Associated Pneumonia (VAP) is a major health problem resulting in death, prolonged intensive care unit (ICU) stay and costs of >£nbn worldwide. Endotracheal tube colonization and biofilm formation play a key role in VAP. Maintenance of the respiratory function of mechanically ventilated patients requires adequate humidification, even in non-invasive ventilation in which inadequate humidification and heating of the inspired air has been associated with functional deterioration of nasal mucosa and can also lead to VAP. Thus, humidification and temperature are important factors of modern intensive care practice.

At the present, there is no technology available to conduct in situ measurement of biofilm growth on an ETT or humidity and temperature of the artificial air delivered to the lungs.

The project will exploit cutting edge sensing techniques based on an array of optical fibre long period gratings in order to produce a prototype multiparameter instrument for a clinical setting to reduce VAP risk, aid early diagnosis and guide treatment. Each sensing element of the optical fibre sensor array will be modified using an appropriate sensitive layer to achieve optimal response to the key parameters of the ETT, such as temperature, humidity and biofilm formation. Novel advanced materials such as molecular imprinting and mesoporous functional films will be utilised as sensitive layers. During the course of the project the device will be tested on clinical equipment, typically used in ICU, in a laboratory setting to demonstrate proof of concept to proceed to clinical studies.

The proposal combines technology push with clinical pull and matches the aspirations of the "Optimising Treatment" Grand Challenge identified by EPSRC to address the optimisation of care through effective diagnosis, patient-specific prediction and evidence-based intervention.

The proposal is multidisciplinary in nature combining expertise in photonics, chemistry and analytical science. The output and impact of the research will be maximised through the involvement of Dr Andy Norris at Nottingham University Hospitals Trust and the involvement of an ETT manufacturer (P3 Medical, a UK SME specialising in the manufacture of innovative, airway devices).

The major beneficiaries of this research will be patients and clinicians. Over 1 million endotracheal tubes (ETT) are placed in patients' tracheas during surgery to support artificial ventilation and/or protect the lungs from inhalation of blood or gastric contents. At any time, around 2000 patients on Intensive Care Units (ICUs) in the UK are receiving artificial ventilation via ETTs, and annually around 20,000 emergency patients require these devices in Emergency Departments. The presence of an ETT is associated with very significant problems such as ventilator associated pneumonia (VAP). The inclusion of a monitoring system within the ETT would enable clinicians to monitor more closely the development of VAP and to intervene at an earlier stage, potentially preventing the causes of VAP. This could facilitate personalised treatment, thus increasing the quality of healthcare. The developed instrument will also have significant impact on the development of hospital instruments and equipment that saves lives; cheap, ubiquitous and instant diagnostics in ICU to increase patient comfort and potentially to prevent the over prescription of antibiotics. This would reduce healthcare cost considerably, as VAP treatment is a >£nbn problem worldwide.

Crucially, this proposal will develop a sensing platform that is inherently adaptable to tackle a range of health care challenges such as early diagnostics, point-of-care sensors, improved patient treatments, antibacterial resistance and personalised medicine. It is anticipated that successful demonstration of its applicability within a clinical environment under this project will lead to the development of commercial instrumentation and clinical trials. Industry involvement via P3 Medical, UK based medical instrument/equipment manufacturing company will insure smooth transition into the market. The proposal will provide strong proof of concept to inform future applications to MRC DPFS/DCS, NIHR (i4i) or Innovate UK Biocatalyst streams to develop the prototype and test in larger clinical trials.

In ICU the developed sensing platform embedded into ETT will:

- Alert clinicians to the accumulation of a microbial reservoir and the presence of common dangerous pathogens, allowing early intervention.
- Help with the diagnosis of VAP, which is notoriously problematic.
- Enable targeted therapy, reducing the need for broad-spectrum antimicrobials, which encourages resistance.
- Provide a highly cost-effective device for reducing VAP incidence since the light source, fibres and electronics are inherently low cost.

The Healthcare Technologies Futures Forum recognised that, over the long term, the availability of low cost, robust, non-invasive technologies capable of providing early diagnosis will impact on the wellbeing of the population, which will have a positive impact on economic activity and productivity, and reduce health service spending. It has been recognised in the Maxwell report that "precision medicine will also become increasingly important in the future, providing tailored healthcare solutions to patients and clinical decision makers" with technology playing a "pivotal role in advances across the field, such as the power of sensors, smartphone technologies and big data computing analysis."