Advice
The technology
The technology
The National Early Warning Score (NEWS2) is a system for scoring the physiological measurements that are routinely recorded at the patient's bedside. Its purpose is to identify acutely ill patients, including those with sepsis, in hospitals in England. The NEWS2 scoring system measures 6 physiological parameters:
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respiration rate
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oxygen saturation
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systolic blood pressure
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pulse rate
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level of consciousness or new-onset confusion
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temperature.
A score of 0, 1, 2 or 3 is allocated to each parameter. A higher score means the parameter is further from the normal range. Appropriate clinical responses are given for threshold (trigger) levels, with a recommendation to review and agree these locally:
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Low risk (aggregate score 1 to 4) – prompt assessment by ward nurse to decide on change to frequency of monitoring or escalation of clinical care.
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Low to medium risk (score of 3 in any single parameter) – urgent review by ward-based doctor to determine cause and to decide on change to frequency of monitoring or escalation of clinical care.
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Medium risk (aggregate score 5 to 6) – urgent review by ward-based doctor or acute team nurse to decide on escalation to critical care team.
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High risk (aggregate score of 7 or over) – emergency assessment by critical care team, usually leading to patient transfer to higher-dependency care area.
The recommendation for a NEWS2 aggregate score of 0 (that is, no change to any parameter) is a minimum 12‑hourly review and to continue routine monitoring.
This briefing focuses on 5 early warning score (EWS) 'track and trigger' systems that can be configured to the NEWS2 specifications. They integrate with electronic health record (EHR) systems to remotely monitor manually entered or automatically captured physiological parameter data directly from bedside patient monitors. They are designed to calculate aggregated scores and automatically generate NEWS2 alerts. This is so that patients in acute and general inpatient wards whose condition is deteriorating are identified and get the appropriate clinical response.
Other, similar technologies may be available but are not included in this briefing (for example, if they were not identified or the company chose not to participate).
The EWS technologies typically consist of a single or modular licensed software application, which integrates with a hospital's existing IT infrastructure. The EWS technologies interface with the hospital's EHR system via electronic health information standards (for example, Health Level 7 [HL7]) to store, access and monitor patient physiological parameter data. They also include hardware, including servers (for example, for the EWS application and database) and desktop or mobile computers, tablets, smartphones, pagers or digital enhanced cordless technology (DECT) phones. These are normally supplied at additional cost by the local hospital's IT services, which use Local Area Networks (LAN) or Wi-Fi to alert clinical staff to deteriorating patients, based on the calculated NEWS2 scores.
Standalone patient bedside monitoring systems with EWS functionality and standalone online or mobile app EWS calculators are out of the scope of this briefing.
The EWS technologies identified and their key features are summarised in table 1.
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EWS system and the company that makes it |
EHR integration |
Data capture |
Mobile alert device types |
CE marking |
|---|---|---|---|---|
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KEWS300 (Syncrophi Systems Ltd) |
Yes, via HL7 and web services API |
Automatic or manual |
Windows and web-based devices |
Class IIb |
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Med eTrax (Med eTrax) |
Yes, via HL7 and web services API |
Automatic (via Bluetooth or Wi-Fi) or manual |
Apple iOS or Windows-based mobile devices |
Self-certification to Class I in progress |
|
Patientrack (Patientrack [UK] Ltd) |
Yes, via HL7 and web services API |
Automatic or manual |
Android, Apple iOS or Windows-based mobile devices; pagers and DECT phones |
Class I |
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SEND (Sensyne Health) |
Yes, via HL7 |
Manual via bedside tablet on roll stand |
Tablet, PC or laptop devices |
Class I |
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CareFlow Vitals (formerly Vitalpac & The Learning Clinic, now produced by System C Healthcare) |
Yes, via HL7 and web services API |
Automatic or manual |
Apple iOS-based mobile devices |
Class I |
Abbreviations: API, application programming interface; DECT, digital enhanced cordless technology; EHR, electronic health record; EWS, Early Warning Score; HL7, health level 7 standard; SEND, System for Electronic Notification and Documentation.
Innovations
Automatic capture of physiological measurements could lead to fewer data input errors to the NEWS2 algorithm than manual recording and fewer calculation errors, giving a more accurate NEWS2 alert. The technology can address issues such as illegible written observations on paper charts.
The potential for greater availability of the NEWS2 alert through the hospital's EHR system and automated alerting could also trigger an earlier clinical response, such as escalation to intensive care and improved recognition of sepsis in hospital-acquired infections.
Such interventions have the potential to benefit patients by reducing avoidable harm, and also benefit the healthcare system, for example by reducing length of hospital stay.
Current care pathway
The NICE guideline on acutely ill adults in hospital: recognising and responding to deterioration recommends that adult patients in acute hospitals should have physiological observations recorded at initial assessment or admission. Physiological observations should then be monitored at least every 12 hours, unless a decision has been made at a senior level to increase or decrease the frequency of monitoring for an individual patient. NICE recommends that 'physiological track and trigger systems' should be used to monitor all adult patients in acute hospitals, with multiple-parameter or aggregated weighted scoring systems used to set trigger thresholds locally. NEWS2 is recommended in the NICE guideline's section on choice of physiological track and trigger system as the system endorsed by NHS England.
NHS England and NHS Improvement mandated NEWS2 for use for adults in acute and ambulance trusts by publishing a Patient Safety Alert for NEWS2 in April 2018 (last updated 9 December 2019), which highlighted resources to support its safe adoption. NEWS2 should not be used in children under 16 or pregnant women. This is because the physiological changes of pregnancy can render the existing NEWS2 inappropriate because the physiological response to acute illness can be modified in children and by pregnancy. Baseline physiological parameters are different in these 2 populations to the non-pregnant, adult population. NHS England, NHS Improvement and the Royal College of Paediatrics and Child Health (RCPCH) are developing a Paediatric Early Warning score (PEWScore) and Paediatric Early Warning System (PEWSystem) as a standardised tool for England. The National PEWS Programme update indicates a pilot roll-out starting in April 2020 and national roll-out starting in November 2020.
The integrated electronic EWS systems in the scope of this briefing may be used in place of the manual recording of NEWS2 parameters on paper charts, and manual calculation, to trigger alerts for appropriate clinical response.
NICE has produced medtech innovation briefings on 3 EWS systems:
Visensia and EarlySense are not NEWS2 compatible and therefore not in the scope of this briefing. NICE's advice on Vitalpac has been updated and replaced by this briefing.
Population, setting and intended user
The EWS systems in the scope of this briefing are for adults in acute and general inpatient wards in secondary care. NEWS2 is used across the NHS in England. It's used by all ambulance trusts and 76% of acute trusts. Other early warning scores are used in other areas (NHS England National Early Warning Score, accessed 4 December 2019). The national clinical lead for deterioration and national clinical adviser for sepsis at NHS England and NHS Improvement said that, at the last count, 139 out of 140 acute trusts in England had either moved to NEWS2 or were in the process of doing so.
The intended users are primarily nursing staff on the wards. The systems could also potentially be used by multidisciplinary clinical teams, which would need to be trained in how to use them. Most companies offer training and ongoing support.
Costs
Technology costs
The costs of EWS systems are based on an assessment of the size of the trust (for example, the planned number of beds to be monitored) and the EWS system functionality required; there is no standard 'list price'. Pricing will also include initial installation, set up and configuration, a software licence, and ongoing support and maintenance. Typical prices range from £30,000 to £90,000 for initial system installation, configuration and set up over 6 to 9 months, with ongoing annual licence costs from £0.35 to £0.70 per acute bed, per day.
Costs of standard care
Standard care is manually recording physiological parameters on NEWS2 paper-based charts, and manual calculation to trigger alerts for the appropriate clinical response. A series of standardised NEWS2 charts can be downloaded for free from the Royal College of Physicians website, which includes:
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Chart 1 – the scoring system for each physiological parameter
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Chart 2 – thresholds and triggers
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Chart 3 – the NEWS2 observation chart
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Chart 4 – the standardised clinical response to NEWS2 trigger thresholds. This includes escalating and de-escalating frequency of monitoring.
Wong et al. (2017) found the mean time taken for nursing staff to capture and record the 6 physiological parameters on paper-based charts and manually calculate the EWS was 3 minutes, 35 seconds (95% confidence interval: 2 minutes 57 seconds to 4 minutes 22 seconds) for 577 nurse events across 3 wards in 1 NHS trust (in 2 university teaching hospitals).
The cost of a nurse on band 4 of the NHS payscale per working hour is £28 (Personal Social Services Research Unit, 2018). Assuming a time of 3 minutes, 35 seconds for a band 4 nurse to manually capture and record the 6 physiological parameters on the chart and calculate the NEWS2, this costs an estimated £1.67 per patient, per observation set (assuming the cost of printing a NEWS2 chart is negligible).
Resource consequences
Wong et al. (2017) found that the mean time taken for nursing staff to capture and record the 6 physiological parameters and calculate a NEWS2-based EWS using the technology reduced to 150 seconds (from 215 seconds with standard care).
Implementing the technology in an NHS trust could require changes to the IT infrastructure and significant upgrade costs during the lifetime of the system. There may be ongoing revenue costs from lost or damaged devices. Staff will need training alongside a phased roll-out of the technology, including an initial session to identify and validate staff as authorised system users. Local policies and procedures will also need to be revised. Also, specific staff training and feedback in managing deterioration is essential to the success of all early warning systems. However, an electronic system would allow feedback to be gathered in real time.
Assuming an average of 3 to 6 sets of observations per day for acute patients in a large trust (1,800 acute beds) then, after installation, the ongoing licence costs of an automated EWS system at £0.35 to £0.70 per acute bed, per day, equates to £229,950 to £459,900 per year. The costs of a band 4 nurse manually recording the same observations and calculating the NEWS2 score would be £3,291,570 to £6,583,140.
Installing automated EWS systems does not save money because the number of staff may not be reduced in practice. But it could release nursing resources. Reductions in reviewing clinician time (doctor availability) should also be considered in the out-of-hours time period.