Development of a novel Paediatric Continuous Early Warning (PaedCEW) monitor for children at risk of respiratory and cardiovascular collapse

Children are not small adults and their bodies respond differently when illness or trauma occur. Throughout childhood, the way the body responds to stresses put on it are dependent on the developmental stage of the child. For example, a 3 month old baby will respond very differently to a teenager during a significant infection such as pneumonia. In this example the breathing rate per minute of the baby could be about 60 but in the teenager just 20. The way the heart responds to illness also varies significantly depending on the age of the child. In children, unlike in adults, the body systems can compensate for illness right up until the time of death. For these reasons, it can be difficult to recognise when children are seriously unwell, as opposed to a simple fever relating to a cold, and this has been highlighted recently by 2 independent reviews of child deaths. Improving the recognition of seriously ill children would be an important step to reducing over and under treatment, reduce the length of hospital stay, reduce the long term health complications associated with advanced illness, and potentially reduce child deaths. With over 800,000 children admitted to hospital in England each year the clinical care of a large number of children could benefit from better monitoring.
There are over 17,000 children admitted to intensive care units each year in the UK with the majority requiring heart and breathing support. Bedside observations such has heart and breathing rate, oxygen levels and skin perfusion can be used to create an early warning score. These scores can identify children with worsening illness allowing timely treatment and prevent the need for intensive care and reduce the risk of death. Unfortunately, these systems can be labour intensive and are non-continuous so could delay urgent treatment if not performed frequently enough. Many emergency paediatric guidelines and early warning systems use capillary refill (a test where the skin is pressed and the time counted for it to return to its original colour once released) as a clinical indicator of cardiovascular status. Although capillary refill is widely used in clinical practice it is well known to have marked observer variability making it less reliable as a clinical guide.
Whilst technology exists to measure key variables such as heart rate, respiratory rate and oxygen saturation, no automated medical device has been developed to monitor capillary refill. Using our patented light technology, we aim to develop an innovative automated capillary refill device with an electronic bedside system to provide a paediatric continuous early warning (PaedCEW) monitoring system. Development of such system would provide a valuable clinical monitor for children that could allow the developmental age of the child to be taken into account. This system could aid the recognition of clinical deterioration in children thus allowing timely intervention.
The device will be non-invasive, require minimal training and operate in an automatic manner providing age specific alarms and alert thresholds. The PaedCEW system would complement and support current clinical practice and aim to address difficulties of recognising ill children. We expect that this device would improve outcomes, reduce healthcare costs via the earlier treatment of children and free up nursing/medical staff time.

There are over 17,000 children admitted to intensive care units annually in the UK with the majority requiring cardiovascular and respiratory support. Recent key reports have highlighted the need for better monitoring of children at risk of deterioration during critical illness. Although paediatric bedside early warning scores, generated via the clinical assessment of physiological observations, can identify these children early this approach is labour intensive, often incomplete, and since it is non-continuous could delay urgent treatment if not performed frequently enough. Many emergency paediatric guidelines and early warning systems use capillary refill as a clinical indicator of cardiovascular status which, although widely used in clinical practice, is known to have marked intra- and inter-observer variability so reducing its power as a clinical guide.
Whilst technology exists to measure key vital signs such as heart rate, respiratory rate and oxygen saturation, no automated medical device has been developed to monitor capillary refill. Using our patented reflectance photoplethysmography technology, we aim to develop an innovative automated capillary refill device and user interface to provide a paediatric continuous early warning (PaedCEW) monitoring system. Although the focus of this proposal is capillary refill assessment, we will develop in parallel an electronic early warning score incorporating key vital signs to aid with the recognition of clinical deterioration in children thus allowing timely intervention.
The device will be non-invasive, require minimal training and operate in a semi-autonomous manner providing age specific alarms and alert thresholds. The PaedCEW system would complement and support current clinical practice and aim to address difficulties of recognising ill children. We expect that this device would improve safety and outcomes in children, reduce healthcare costs via the earlier treatment and free up nursing/medical staff time.

The proposed project could have a real impact on a number of beneficiaries.

The greatest beneficiaries of this project will be children. If we are able to establish the potential for this device to aid the timely recognition of serious illness then both morbidity and mortality could be reduced. This device aims to improve the clinical monitoring and safety of children, especially young children in whom verbal communication is often not possible, for example a 1 year old with worsening infection cannot communicate this at 2am when nursing and medical cover is often minimal.

The academic impact could be significant with new knowledge relating to the interaction between the cardiovascular system and the skin. This will be of interest to physiologists and those interested in the pathophysiology of disease in children. The potential to non-invasively monitor and quantify tissue blood flow simultaneously in the peripheral and central areas will further the field of paediatric critical care. There is increasing recognition of the difficulties of non-invasive cardiovascular monitoring in children with attempts to identify better ways of achieving this. Our device could potentially be used to do that and provide a quantitative target for goal-directed therapy in sick children. Further work on the device could potentially allow it to be used in adults and extremely preterm babies.

The development of the graphical user interface and the user needs assessment will offer insight into the human factors and usability required for development of bedside devices. This will not only be of interest to researchers but will also benefit healthcare device manufacturers and healthcare professionals.

Our proposal also incorporates an electronic multi-parameter paediatric early warning system. This offers the potential to develop new and more powerful diagnostics for recognising ill patients. Additionally, it could free up more time for healthcare professionals to focus on patient satisfaction, quality and other aspects of medical care. The potential improvements to patient safety are also clear and go some way to addressing concerns raised about the recognition of ill children.

In the engineering domain, there will advancements in the signal processing and algorithms associated with cutaneous perfusion across a variety of skins types and patient age groups. With the use of a 530nm wavelength of light additional data will become available as this moves away from the more commonly used red or infra-red wavelengths. Furthermore, all too often technology is developed in adults for adults, this device is targeted at the paediatric population and will gain new insights into technological developments in this respect.

Our team is also keen to train the next generation of medical device engineers and clinical academics. By combing the engineer and clinical fellow on the project there will be a cross pollination of skills and knowledge that will benefit all involved.

Successful development of our device and warning system could allow engagement with a major healthcare device manufacturer or formation of spin-out company. This would offer economic benefits for the University, the UK and, if launched and taken up internationally, could strengthen UK's global standing in the development of new technologies. In addition, the University of Nottingham is gaining a reputation for fetal and paediatric device development and this device could attract further international funding by establishing industrial and corporate partnerships.

The recent VITAL trial (unpublished) has recently completed and early data suggests that the use of an electronic bedside early warning device in adults can reduce mortality and length of hospital stay. Beyond the potential safety benefits, our system could have a similar impact potentially reducing healthcare associated costs, this would be particularly important for the NHS and ultimately UK taxpayer.