NEWS score: Detecting clinical deterioration

The NEWS score is a clinical tool designed to assist clinicians in the early detection of clinical deterioration of patients.

It began life as the Early Warning Score, and rose in popularity in the 1990s as an effective way of improving patient safety. Initially the use case was prediction of cardiac arrest, before expanding more generally to clinical deterioration.

The basis of any Early Warning Score is the understanding that preceding any negative medical event there is increased variability and abnormality within physiological observations. It can be one of many useful tools in maintaining healthcare quality standards and safety for patients.

The evolution of Early Warning Scores

Wright MM et al presented “An early warning scoring system for detecting developing critical illness” at the United Kingdom Intensive Care Society Conference in 1997.

It was, and continues to be, a physiological point scoring system that efficiently identifies and should trigger an appropriate response to patients who present with or develop acute illness.

Why is this important?

As described by the UK Resus Council, ‘early recognition and response [to] deterioration improves patient safety and outcomes.’

This gives clinicians the ability to engage in risk stratification. That is, we are able to both identify and predict which patients are currently or becoming high risk. Therefore their management can be prioritised in contrast with other responsibilities to minimise deterioration and improve patient outcomes.

After initial implementation, it became clear that there were clinical situations and patient demographics that could benefit from a score amended for each purpose.

Common variations of the original Early Warning Score include:

The National Early Warning Score

Following on from widespread uptake of the EWS across the UK, The Royal College of Physicians designed the new National Early Warning Score.

It sought to remove regional variability of locally amended Early Warning Scores, and has come into both UK national and international use since 2012. This includes European, American and military applications.

A second, improved version of NEWS, dubbed NEWS2, was brought into use in 2017. This sought to strengthen weak areas of the original score.

Feedback from the original score mainly indicated weakness when reviewing COPD patients. It was updated with this inclusion, as well as refining identification of sepsis and the onset of delirium.

NEWS2 is due for review and update in 2023.

How NEWS works

The description that follows has been published by the Royal College of Physicians – the originators of NEWS and NEWS2.

The NEWS is based on a simple aggregate scoring system in which a score is allocated to physiological measurements, already recorded in routine practice, when patients present to, or are being monitored in hospital. Six simple physiological parameters form the basis of the scoring system:

1. respiration rate
2. oxygen saturation
3. systolic blood pressure
4. pulse rate
5. level of consciousness or new confusion*
6. temperature.

*The patient has new-onset confusion, disorientation and/or agitation, where previously their mental state was normal – this may be subtle. The patient may respond to questions coherently, but there is some confusion, disorientation and/or agitation. This would score 3 or 4 on the GCS (rather than the normal 5 for verbal response), and scores 3 on the NEWS system.

A score is allocated to each parameter as they are measured, with the magnitude of the score reflecting how extremely the parameter varies from the norm. The score is then aggregated and uplifted by 2 points for people requiring supplemental oxygen to maintain their recommended oxygen saturation.

The above score is used to track over time but also to alert clinicians to important thresholds. The Royal College of Physicians recommends the following four ‘trigger levels’:

1. LOW score: an aggregate NEW score of 1–4
2. A single red score: an extreme variation in an individual physiological parameter (a score of 3 in any one parameter, which is colour-coded red on the NEWS2 chart)
3. MEDIUM score: an aggregate NEW score of 5 or 6. A NEW score of 5 or more is a key threshold and is indicative of potential serious acute clinical deterioration and the need for an urgent clinical response
4. HIGH score: an aggregate NEW score of 7 or more

NEWS2 vs NEWS

There have been a number of updates from the original NEWS chart to the now common NEWS2 chart in use around the world. In the NEWS2 chart:

1. the recording of physiological parameters has been reordered to align with the Resuscitation Council (UK) ABCDE sequence
2. the ranges for the boundaries of each parameter score are now shown on the chart
3. the chart has a dedicated section (SpO 2 Scale 2) for use in patients with hypercapnic respiratory failure (usually due to COPD) who have clinically recommended oxygen saturation of 88–92%
4. the section of the chart for recording the rate of (L/min) and method/device for supplemental oxygen delivery has been improved
5. the importance of considering serious sepsis in patients with known or suspected infection, or at risk of infection, is emphasised. A NEW score of 5 or more is the key trigger threshold for urgent clinical review and action
6. the addition of ‘new confusion’ (which includes disorientation, delirium or any new alteration to mentation) to the AVPU score, which becomes ACVPU (where C represents confusion)
7. the chart has a new colour scheme, reflecting the fact that the original red–amber–green colours were not ideal for staff with red/green colour blindness

NEWS2 & Digital Healthcare Technologies

The NEWS is well positioned due to its simplicity to be translated into existing and incoming digital health platforms.

There has already been some development in this area, with starter attempts to integrate NEWS into Electronic Healthcare Records or stand-alone apps.

There is much scope in the future for improved integration of NEWS, with automated measurements, calculations and alerts for staff further expanding on the benefits of use.

Tracking acute illness severity

Tools are inert and useless until they are properly utilised by those who understand how to use said tool.

This means that NEWS scores or any variation need to:

• Be used with the correct, intended demographic
• Kept up to date
• Calculated correctly
• Interpreted correctly
• Inform appropriate staff in a time manner
• Acted upon

Using NEWS2 with COVID patients

The Royal College of Physicians have made a minor but important note surrounding use of the score with COVID patients. Whilst it still remains that the score will identify those deteriorating or at risk of deteriorating, it relies on a binary system for oxygen requirements.

That is, patients with increased oxygen needs should be escalated in line with this increase.

To directly quote the Royal College again:

In patients with COVID-19 infection, once hospitalised and treated with oxygen, their oxygen requirement might increase rapidly if their respiratory function deteriorates but this may not result in any additional significant increase in the NEWS2 score. 

Therefore, in patients with COVID 19, all staff should be aware that ANY increase in oxygen requirements should trigger an escalation call to a competent clinical decision maker. This should be accompanied by an initial increase in observations to at least hourly until a clinical review happens, if this has not already happened as a result of NEWS2.

Over Reliance on Early Warning Scoring Systems

While NEWS and its derivations have been an excellent tool for decreasing morbidity and mortality worldwide, as with any summary tool it has limitations.

A bracketed and static scoring system will never be able to replace the nuance and intuition that comes from a lifetime of clinical experience and work.

Perhaps at the forefront of this disparity are nurses. Nursing staff, caring for a limited number of patients, typically in a bay or similar, get to know and understand their patients on a deeper level.

This can result in ‘worry calls’. Worry calls are when the nurse, often rightly, through their day to day monitoring of the patient notices deterioration in a patient before anything overt can be seen on charts. Certainly before triggering a significant rise in the scoring system.

Doctors and other allied healthcare professionals would do well to not ignore these calls on the basis of an unchanging score.

While these nurses’ concerns are based on feelings rather than facts, systemic review has shown that nurses develop this important skill over time, allowing them to detect and pre-empt patients in need of attention, often prior to vital sign changes. 

Although there are a number of studies, their heterogeneity makes interpretation unclear. What is apparent however, is that ‘worry calls’ not dependent on physiological observations have the ability to improve patient outcomes and should therefore be taken seriously as would any other call regarding poor patient condition.

The Future of NEWS

By providing objective, standardised data on patient physiology over time, collection of NEWS data opens up numerous possibilities for research and predictive modelling.

This base framework of data also provides a control by which new institutions, teams and therapeutic interventions can all be measured against in terms of efficacy.

NEWS has created a significant shift in patient monitoring and clinician response, bringing important standardisation and scope for future research and development.