The technology

RespiraSense (PMD Solutions) is a motion-tolerant digital technology for continuously monitoring respiratory rate. It is intended to be used by people admitted to hospital who are at risk of respiratory compromise and are having over 4 litres per minute of oxygen or are on high flow or non-invasive ventilation treatment. It can be used across multiple indications, such as pneumonia, sepsis, chronic obstructive pulmonary disease, heart failure and COVID-19.

RespiraSense is a wearable sensor that is made up of 2 parts: a single-use adhesive sensor and a rechargeable plastic lobe, which are joined together and attached to the chest. It continuously records respiratory data when a person is moving or walking. People can wear the device continuously from admission to discharge from hospital. RespiraSense measures the repetitive mechanical movement of breathing by analysing the movements of the chest and abdomen using piezoelectric film sensors. The device processes the breathing signals and uses an algorithm to remove background noise not associated with breathing.

Data collected by the device is transmitted by a Bluetooth connection to a smart device, such as an iPad or smartphone, where it can be viewed by healthcare professionals using the RespiraSense app. The app also allows healthcare professionals to monitor multiple RespiraSense devices at once. Both the device and the smart device will alarm if the respiratory rate changes and is outside of preset limits. RespiraSense can integrate with any electronic health record system or can be used as a stand-alone respiratory monitor.


RespiraSense continuously monitors respiratory rate while a person is walking or changing body position. It processes breathing signals depending on how much motion has been observed and combines 2 respiratory rates (1 from the chest data and 1 from the abdominal data). The company claims that motion tolerance and comparing multiple respiratory signals improves respiratory rate measurement accuracy. The company claims that this could lead to earlier identification of respiratory deterioration and improve patient outcomes.

Current care pathway

RespiraSense is intended to be used for people admitted to hospital who are at risk of respiratory compromise. It can be used across multiple indications to continuously monitor respiratory rate.

Adults in acute hospital settings have physiological measurements taken during their initial assessment or on admission. A clear written monitoring plan should be created that specifies which physiological observations should be recorded and how often. As a minimum, this should include respiratory rate, heart rate, systolic blood pressure, level of consciousness, oxygen saturation and temperature. This should be at least every 12 hours unless decided otherwise based on the person's needs. Respiratory rate should be recorded and acted on by staff who have been trained to do the procedure and understand its clinical relevance.

Early warning score 'track and trigger' systems should be used to monitor all adults in acute hospital settings to alert healthcare professionals to any deterioration in a person's health. The National Early Warning Score (NEWS) 2 uses 6 routinely recorded physiological parameters, including respiratory rate, and is endorsed by NHS England. Changes in respiratory rate should be considered as part of the escalation of treatment for people in an acute care setting.

Respiratory rate is currently measured by manually counting the number of breaths per minute. It can also be measured using impedance pneumography, electrocardiography and capnography (a measurement of carbon dioxide in a person's exhaled breath). Capnography is considered the 'gold standard' for measuring respiratory rate but is rarely used in a ward setting.

The following publications have been identified as relevant to this care pathway:

Population, setting and intended user

RespiraSense is intended to be used by people admitted to hospital who are at risk of respiratory compromise and are having over 4 litres per minute of oxygen or are on high flow or non-invasive ventilation treatment. It can be used across multiple indications, including pneumonia, sepsis, chronic obstructive pulmonary disease, heart failure and COVID-19. RespiraSense should not be used during defibrillation, MRI, X‑ray or other medical imaging procedures. The technology should not be used for newborn or baby monitoring.

RespiraSense can be used to measure respiratory rate in an acute hospital setting. The company notes that it could also be used in a person's home as part of monitoring in virtual wards.

The technology can be used by different healthcare professionals, including nurses, physiotherapists and healthcare assistants. Clinical users are trained in device set up, collecting continuous respiratory rate, and reviewing and reporting on the monitoring. They are also trained to select people for monitoring according to local protocols and guidance. The company states that they provide free initial and refresher training, which typically takes 20 to 30 minutes to complete.


Technology costs

The company states that the average cost of RespiraSense per person is approximately £76 (based on an estimated average number of people who would use the device for 1 acute care ward).

A RespiraSense kit (including 6 reusable and rechargeable plastic lobes, charging station, and iPad) costs £5,000 per unit (excluding VAT). The disposable wearable sensor costs £35 per unit. The company claims that the rechargeable plastic lobes have a minimum lifespan of 5 years, and the disposable sensors have a lifespan of 168 hours before needing replacement. The company states that there is an initial installation and test cost per hospital of £4,800, and a local Bluetooth network and server connection cost per hospital of £7,200. The company states that 1 kit is needed per hospital ward, and further wards can be added with no increase in IT infrastructure costs. Device costs, installation and data connectivity costs may vary depending on local factors that will be assessed at the design stage of adoption.

Costs of standard care

National 'track and trigger' systems can be automated or paper based. Paper-based early warning score charts are free to download from the Royal College of Physicians website. Wong et al. (2017) reported that it takes 3 minutes 35 seconds of nursing time to do manual observations and early warning score calculations. Based on the agenda for change NHS pay scales 2022/23 band 5 nursing salary, the cost of recording and calculating the early warning score manually is £0.78 per person.

The cost of handheld and bedside capnograph monitors listed on NHS Supply Chain range from around £1,200 to over £2,000. There may be additional costs for replacement accessories. Locally agreed prices may differ.

Resource consequences

The company states that the technology is currently used in 1 NHS trust across 3 acute respiratory wards.

RespiraSense is intended to be used alongside intermittent nurse-led monitoring and so will initially cost more than current standard care alone. The company claims that the technology could lead to cost savings by identifying people at risk of respiratory deterioration earlier and allowing for earlier interventions, such as ventilatory support or antibiotics. It could also lead to reducing the length of hospital stay, reducing hospital re-admission rates and improving long-term health outcomes.

The company states that typical requirements for technology adoption include additional network and mains power points if none are available. The company claims that no additional personnel are needed to run the system, but a collaborative team approach with hospital IT security and risk assessment departments are needed for successful implementation of the RespiraSense system.