Early warning scores: unravelling detection and escalation

Prevalence and characteristics of medical emergency teams in Switzerland: a nationwide survey of intensive care units

BACKGROUND

Medical Emergency Teams (METs) have been implemented in many hospitals worldwide and are considered an integral part of the hospital patient safety system. However, data on prevalence, staffing and activation criteria of METs are scarce. Such data are important as they may help to identify areas of quality improvement and barriers to implementation of rapid response systems (RRS). This survey aimed to analyze current characteristics, prevalence, and organization of METs in Switzerland.

METHODS

We conducted a cross-sectional nationwide online survey, inviting physicians' and nurses' representatives from all registered adult intensive care units (ICU) in Switzerland.

RESULTS

Of the 74 hospitals invited to participate in the survey, 57 responded (response rate 77%). We obtained 82 individual responses (from 50 physicians and 32 nurses). Twenty-five hospitals (44%) have a MET in place. In most Swiss hospitals, METs are composed of ICU consultants (64%) and ICU nurses (40%) and are activated by phone, with a usual response time of less than 10 minutes. The most common triggers are single abnormal vital signs (80%), while multiple-parameter warning scores are less commonly used (28%). While more than half of the nurses have regular trainings for their MET members (57%), most MET physicians (63%) do not. Systematic data collection of MET calls occurs in only 43% of institutions. Finally, the most common reasons for not having a MET are staff shortage (44%) and lack of funding (19%).

CONCLUSIONS

Less than 50% of Swiss hospitals with an adult ICU have a MET in place. METs in Switzerland typically include an ICU doctor and an ICU nurse and are available 24/7. Major barriers to MET introduction are staff shortage and lack of funding.

Use of illness severity scores to predict mortality in interstitial lung disease patients hospitalised with acute respiratory deterioration

INTRODUCTION

Hospitalisations relating to acute respiratory deteriorations (ARD) in Interstitial Lung Disease (ILD) have poor outcomes. Factors predicting adverse outcomes are not fully understood and data addressing the use of illness severity scores in prognostication are limited.

OBJECTIVE

To investigate the use of CURB-65 and NEWS-2 severity scores in the prediction of mortality following ARD-ILD hospitalisation, using prospective methodology and to validate previously determined cut-offs, derived from a retrospective study cohort.

METHODS

A dual-centre prospective observational cohort study of all adults (≥18y) hospitalised with ARD-ILD in Bristol, UK (n = 179). Gender-Age-Physiology (GAP), CURB-65 and NEWS-2 scores were calculated for each eligible admission. Receiver operating characteristics (ROC) curve analysis was used to quantify the strength of discrimination for NEWS-2 and CURB-65 scores. Univariable and multivariable logistic regression analyses were performed to explore the relationship between baseline severity scores and mortality.

RESULTS

GAP showed some merit at predicting 30-day mortality (AUC = 0.64, P = 0.015); whereas CURB-65 showed modest predictive value for in-hospital (AUC = 0.72, P < 0.001) and 90-day mortality (AUC = 0.67, P < 0.001). NEWS-2 showed higher predictive value for in-hospital (AUC = 0.80, P < 0.001) and 90-day mortality (AUC = 0.75, P < 0.001), with an optimal derived cut-off ≥6.5 found to be sensitive and specific for predicting in-hospital (83% and 63%) and 90-day (73% and 72%) mortality. In exploratory analyses, GAP score addition improved the predictive ability of NEWS-2 against 30-day mortality and CURB-65 across all time-periods.

CONCLUSION

NEWS-2 has good discriminatory value for predicting in-hospital mortality and moderate discriminatory value for predicting 90-day mortality. The optimal NEWS-2 cut-off value determined was the same as in a previous retrospective cohort, confirming the NEWS-2 score shows promise in predicting mortality following ARD-ILD hospitalisation.

Implementation of a digital early warning score (NEWS2) in a cardiac specialist and general hospital settings in the COVID-19 pandemic: a qualitative study

OBJECTIVES

To evaluate implementation of digital National Early Warning Score 2 (NEWS2) in a cardiac care setting and a general hospital setting in the COVID-19 pandemic.

DESIGN

Thematic analysis of qualitative semistructured interviews using the non-adoption, abandonment, scale-up, spread, sustainability framework with purposefully sampled nurses and managers, as well as online surveys from March to December 2021.

SETTINGS

Specialist cardiac hospital (St Bartholomew's Hospital) and general teaching hospital (University College London Hospital, UCLH).

PARTICIPANTS

Eleven nurses and managers from cardiology, cardiac surgery, oncology and intensive care wards (St Bartholomew's) and medical, haematology and intensive care wards (UCLH) were interviewed and 67 were surveyed online.

RESULTS

Three main themes emerged: (1) implementing NEWS2 challenges and supports; (2) value of NEWS2 to alarm, escalate and during the pandemic; and (3) digitalisation: electronic health record (EHR) integration and automation. The value of NEWS2 was partly positive in escalation, yet there were concerns by nurses who undervalued NEWS2 particularly in cardiac care. Challenges, like clinicians' behaviours, lack of resources and training and the perception of NEWS2 value, limit the success of this implementation. Changes in guidelines in the pandemic have led to overlooking NEWS2. EHR integration and automated monitoring are improvement solutions that are not fully employed yet.

CONCLUSION

Whether in specialist or general medical settings, the health professionals implementing early warning score in healthcare face cultural and system-related challenges to adopting NEWS2 and digital solutions. The validity of NEWS2 in specialised settings and complex conditions is not yet apparent and requires comprehensive validation. EHR integration and automation are powerful tools to facilitate NEWS2 if its principles are reviewed and rectified, and resources and training are accessible. Further examination of implementation from the cultural and automation domains is needed.

Rapid response teams-how and who? A protocol for a randomised clinical trial evaluating the composition of the efferent limb of the rapid response system

BACKGROUND

Many patients experiencing deterioration have documented deviation of vital signs prior to the deterioration event. Increasing focus on these patients led to the rapid response systems and their configuration with afferent and efferent limbs. The two most prevalent team constellations in the efferent limb are the medical emergency team (MET), usually led by a doctor, and the critical care outreach team (CCOT), usually led by a nurse. The two constellations have not previously been examined in a comparative clinical trial.

METHODS

This is a single centre non-inferiority randomised controlled trial of MET vs CCOT. All patients will be randomised at the time of the call. The intervention group will be the critical care outreach team. The primary outcome is mortality at 30 days and the occurrence of serious adverse events. All patients will be followed for 90 days. We aim to detect or reject a change of 7% in mortality whilst accepting a type I error of 5 and type II error of 20, using a sample size of maximum of 2000 individual patients.

DISCUSSION

There is evidence supporting a benefit for the patient when using rapid response systems; however, earlier randomised studies are marked by cross-contamination and selection bias. Previous studies have primarily examined the effect of RRS on hospital cardiac arrests (IHCA) and mortality. Our study will be examining the effect on intensive care unit admissions as well as the ICHA and mortality.

CONCLUSION

This study may highlight potential benefits of specific configurations of rapid response systems and their impact on safety outcomes.

Utility of illness severity scores to predict mortality in patients hospitalized with respiratory deterioration of idiopathic pulmonary fibrosis

INTRODUCTION

In the context of idiopathic pulmonary fibrosis (IPF), respiratory-related admissions to hospital are associated with a high morbidity and short-term mortality with significant burden on secondary care services. It has yet to be determined how to accurately identify patients at risk of acute respiratory deterioration (ARD) or the prognosticating factors.

AIM

We sought to define the characteristics of hospitalized ARD-IPF patients in a real-world cohort and investigate factors associated with worse outcomes. Specifically, we wished to determine the association between baseline CURB-65 and NEWS-2 and mortality in IPF, given illness severity scores have not previously been validated in this cohort.

METHODS

Single-centre retrospective observational cohort study.

RESULTS

Of 172 first hospitalizations for ARD, 27 admissions (15.7%) were due to an acute exacerbation of IPF (AE-IPF), 28 (16.3%) secondary to cardiac failure/fluid overload and 17 due to pneumonia (9.9%). Other admissions related to lower respiratory tract infection, extra-parenchymal causes and those without a specific trigger. Baseline patient characteristics were comparable for all underlying aetiologies of ARD-IPF. Treatment pathways did not differ significantly between AE-IPF and other causes of ARD-IPF. Short-term mortality was high, with ∼22% patients dying within 30 days. Illness severity scores (NEWS-2 and CURB-65) were independent predictors of mortality in multivariable logistic regression modelling.

CONCLUSIONS

Our findings suggest significant mortality related to hospitalization with ARD-IPF of any underlying cause. Our data support the use of CURB-65 and NEWS-2 scores as illness severity scores that can provide a simple tool to help future prognostication in IPF. Research should be aimed at refining the management of these episodes, to try to reduce mortality, where possible, or to facilitate palliative care for those with adverse prognostic characteristics.

The performance of the National Early Warning Score and National Early Warning Score 2 in hospitalised patients infected by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)

INTRODUCTION

Since the introduction of the UK's National Early Warning Score (NEWS) and its modification, NEWS2, coronavirus disease 2019 (COVID-19), has caused a worldwide pandemic. NEWS and NEWS2 have good predictive abilities in patients with other infections and sepsis, however there is little evidence of their performance in COVID-19.

METHODS

Using receiver-operating characteristics analyses, we used the area under the receiver operating characteristic (AUROC) curve to evaluate the performance of NEWS or NEWS2 to discriminate the combined outcome of either death or intensive care unit (ICU) admission within 24 h of a vital sign set in five cohorts (COVID-19 POSITIVE, n = 405; COVID-19 NOT DETECTED, n = 1716; COVID-19 NOT TESTED, n = 2686; CONTROL 2018, n = 6273; CONTROL 2019, n = 6523).

RESULTS

The AUROC values for NEWS or NEWS2 for the combined outcome were: COVID-19 POSITIVE, 0.882 (0.868-0.895); COVID-19 NOT DETECTED, 0.875 (0.861-0.89); COVID-19 NOT TESTED, 0.876 (0.85-0.902); CONTROL 2018, 0.894 (0.884-0.904); CONTROL 2019, 0.842 (0.829-0.855).

CONCLUSIONS

The finding that NEWS or NEWS2 performance was good and similar in all five cohorts (range = 0.842-0.894) suggests that amendments to NEWS or NEWS2, such as the addition of new covariates or the need to change the weighting of existing parameters, are unnecessary when evaluating patients with COVID-19. Our results support the national and international recommendations for the use of NEWS or NEWS2 for the assessment of acute-illness severity in patients with COVID-19.

The effectiveness of a national early warning score as a triage tool for activating a rapid response system in an outpatient setting: A retrospective cohort study

Rapid response system (RRS) efficacy and national early warning score (NEWS) performances have largely been reported in inpatient settings, with few such reports undertaken in outpatient settings.This study aimed to investigate NEWS validity in predicting poor clinical outcomes among outpatients who had activated the RRS using single-parameter criteria.A single-center retrospective cohort studyFrom April 1, 2014 to November 30, 2017 in an urban 350-bed referral hospital in JapanWe collected patient characteristics such as activation triggers, interventions, arrival times, dispositions, final diagnoses, and patient outcomes. Poor clinical outcomes were defined as unplanned intensive care unit transfers or deaths within 24 hours. Correlations between the NEWS and clinical outcomes at the time of deterioration and disposition were analyzed.Among 31 outpatients, the NEWS value decreased significantly after a medical emergency team intervention (median, 8 vs 4, P < .001). The difference in the NEWS at the time of deterioration and at disposition was significantly less in patients with poor clinical outcomes (median 3 vs 1.5, P = .03). The area under the curve (AUC) for the NEWS high-risk patient group at the time of deterioration for predicting hospital admission was 0.85 (95% confidence interval [CI], 0.67-1.0), while the AUC for the NEWS high-risk patient group at disposition for predicting poor clinical outcomes was 0.83 (95% CI, 0.62-1.0).The difference between the NEWS at the time of deterioration and at disposition might usefully predict admissions and poor clinical outcomes in RRS outpatient settings.

Limitations of track and trigger systems and the National Early Warning Score. Part 1: areas of contention

Evidence suggests that the identification and response to the deteriorating patient continues to be an ongoing concern, despite the widespread use of track and trigger score (TTS) systems. This article discusses the variations in the parameters included in the different TTS systems in use across the NHS and their sensitivity. Clinical guidelines and physiological theory are used to appraise the parameters allocated in the National Early Warning Score (NEWS 1 and 2), highlighting potential limitations of the tool. The findings lead to the conclusion that registered nurses should not rely solely on NEWS, but should use it to support their clinical judgement.

Use of National Early Warning Score for observation for increased risk for clinical deterioration during post-ICU care at a surgical ward

Purpose

Patients transferred from an intensive care unit (ICU) to a general ward are at risk for clinical deterioration. The aim of the study was to determine if an increase in National Early Warning Score (NEWS) value predicted worse outcomes in surgical ward patients previously treated in the ICU.

Patients and methods

A retrospective observational study was conducted in a cohort of gastrointestinal surgery patients after transfer from an ICU/high dependency unit (HDU). NEWS values were collected throughout the ward admission. Clinical deterioration was defined by ICU readmission or death. The ability of NEWS to predict clinical deterioration was determined using a linear mixed effect model.

Results

We included 124 patients, age 65.9±14.5, 60% males with an ICU Simplified Acute Physiology Score II 33.8±12.7. No patients died unexpectedly at the ward and 20 were readmitted to an ICU/HDU. The NEWS values increased by a mean of 0.15 points per hour (intercept 3.7, P<0.001) before ICU/HDU readmission according to the linear mixed effect model. NEWS at transfer from ICU was the only factor that predicted readmission (OR 1.32; 95% CI 1.01–1.72; P=0.04) at the time of admission to the ward.

Conclusion

Clinical deterioration of surgical patients was preceded by an increase in NEWS.

Prognostic accuracy of the Hamilton Early Warning Score (HEWS) and the National Early Warning Score 2 (NEWS2) among hospitalized patients assessed by a rapid response team

Background

Rapid response teams (RRTs) respond to hospitalized patients experiencing clinical deterioration and help determine subsequent management and disposition. We sought to evaluate and compare the prognostic accuracy of the Hamilton Early Warning Score (HEWS) and the National Early Warning Score 2 (NEWS2) for prediction of in-hospital mortality following RRT activation. We secondarily evaluated a subgroup of patients with suspected infection.

Methods

We retrospectively analyzed prospectively collected data (2012–2016) of consecutive RRT patients from two hospitals. The primary outcome was in-hospital mortality. We calculated the number needed to examine (NNE), which indicates the number of patients that need to be evaluated in order to detect one future death.

Results

Five thousand four hundred ninety-one patients were included, of whom 1837 (33.5%) died in-hospital. Mean age was 67.4 years, and 51.6% were male. A HEWS above the low-risk threshold (≥ 5) had a sensitivity of 75.9% (95% confidence interval (CI) 73.9–77.9) and specificity of 67.6% (95% CI 66.1–69.1) for mortality, with a NNE of 1.84. A NEWS2 above the low-risk threshold (≥ 5) had a sensitivity of 84.5% (95% CI 82.8–86.2), and specificity of 49.0% (95% CI: 47.4–50.7), with a NNE of 2.20. The area under the receiver operating characteristic curve (AUROC) was 0.76 (95% CI 0.75–0.77) for HEWS and 0.72 (95% CI: 0.71–0.74) for NEWS2. Among suspected infection patients (n = 1708), AUROC for HEWS was 0.79 (95% CI 0.76–0.81) and for NEWS2, 0.75 (95% CI 0.73–0.78).

Conclusions

The HEWS has comparable clinical accuracy to NEWS2 for prediction of in-hospital mortality among RRT patients.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2355-3) contains supplementary material, which is available to authorized users.

Bedside vital parameters that indicate early deterioration

Purpose

The purpose of this paper is to determine associations between initially recorded deviations in individual bedside vital parameters that contribute to total Modified Early Warning Score (MEWS) levels 2 or 3 and further clinical deterioration (MEWS level=4).

Design/methodology/approach

This was a prospective study in which 27,504 vital parameter values, corresponding to a total MEWS level⩾2, belonging to 1,315 adult medical and surgical inpatient patients admitted to a 90-bed study setting at a university hospital, were subjected to binary logistic and COX regression analyses to determine associations between vital parameter values initially corresponding to total MEWS levels 2 or 3 and later deterioration to total MEWS level ⩾4, and to evaluate corresponding time intervals.

Findings

Respiratory rate, heart rate and patient age were significantly (p=0.012, p<0.001 and p=0.028, respectively) associated with further deterioration from a total MEWS level 2, and the heart rate also (p=0.009) from a total MEWS level 3. Within 24 h from the initially recorded total MEWS levels 2 or 3, 8 and 17 percent of patients, respectively, deteriorated to a total MEWS level=4. Patients initially scoring MEWS 2 had a 27 percent 30-day mortality rate if they later scored MEWS level=4, and 8.7 percent if they did not.

Practical implications

It is important to observe all patients closely, but especially elderly patients, if total MEWS levels 2 or 3 are tachypnoea and/or tachycardia related.

Originality/value

Findings might contribute to patient safety by facilitating appropriate clinical and organizational decisions on adequate time spans for early warning scoring in general ward patients.

How do nurses use the early warning score in their practice? A case study from an acute medical unit

AIMS AND OBJECTIVES

This study aimed to describe how nurses use the early warning score (EWS) in an acute medical ward and their compliance with the EWS and explore their views and experiences of the EWS.

BACKGROUND

early warning score systems have been implemented in response to upward trends in mortality rates. Nurses play a central role in the use of EWS systems. However, barriers to their use have been identified and include behavioural, cultural and organisational approaches to adherence. Improvement strategies including education and training and electronic devices have assisted in compliance with the system.

DESIGN

A holistic single descriptive case study design was used.

METHODS

Data triangulation was used including non-participant observation, semi-structured interviews with nurses and document analysis. Nurses were observed using EWS and were subsequently interviewed. Data analysis was guided by systematic text condensation (STC), an approach underpinned by Giorgi's phenomenological method, where meaning units and themes are identified. The study adhered to the consolidated criteria for reporting qualitative research (COREQ) guidelines.

RESULTS

Three themes with associated meaning units were found. Protocol Adherence vs. Clinical Judgement addresses nurses' knowledge, skill and experience and patient assessment. Parameter Adjustment and Escalation included parameters not being adjusted or reviewed, junior doctors not being authorised to set parameters and escalation. The final theme Culture highlighted a task-driven approach and deficient communication processes.

CONCLUSION

This study highlights the need for ongoing training, behavioural change and a cultural shift by healthcare professionals and organisations to ensure adherence with EWS escalation protocols.

RELEVANCE TO CLINICAL PRACTICE

Improvements in education and training into recognition, management and communication of a deteriorating patient are required. Also, a cultural shift is needed to improve compliance and adherence with EWS practice. The potential use of electronic data should be explored.

A comparison of the ability of the National Early Warning Score and the National Early Warning Score 2 to identify patients at risk of in-hospital mortality: A multi-centre database study

Aims

To compare the ability of the National Early Warning Score (NEWS) and the National Early Warning Score 2 (NEWS2) to identify patients at risk of in-hospital mortality and other adverse outcomes.

Methods

We undertook a multi-centre retrospective observational study at five acute hospitals from two UK NHS Trusts. Data were obtained from completed adult admissions who were not fit enough to be discharged alive on the day of admission. Diagnostic coding and oxygen prescriptions were used to identify patients with type II respiratory failure (T2RF). The primary outcome was in-hospital mortality within 24 h of a vital signs observation. Secondary outcomes included unanticipated intensive care unit admission or cardiac arrest within 24 h of a vital signs observation. Discrimination was assessed using the c-statistic.

Results

Among 251,266 adult admissions, 48,898 were identified to be at risk of T2RF by diagnostic coding. In this group, NEWS2 showed statistically significant lower discrimination (c-statistic, 95% CI) for identifying in-hospital mortality within 24 h (0.860, 0.857–0.864) than NEWS (0.881, 0.878-0.884). For 1394 admissions with documented T2RF, discrimination was similar for both systems: NEWS2 (0.841, 0.827-0.855), NEWS (0.862, 0.848–0.875). For all secondary endpoints, NEWS2 showed no improvements in discrimination.

Conclusions

NEWS2 modifications to NEWS do not improve discrimination of adverse outcomes in patients with documented T2RF and decrease discrimination in patients at risk of T2RF. Further evaluation of the relationship between SpO₂ values, oxygen therapy and risk should be investigated further before wide-scale adoption of NEWS2.

Clinical frailty adds to acute illness severity in predicting mortality in hospitalized older adults: An observational study

AIM

Frail individuals may be at higher risk of death from a given acute illness severity (AIS), but this relationship has not been studied in an English National Health Service (NHS) acute hospital setting.

METHODS

This was a retrospective observational study in a large university NHS hospital in England. We analyzed all first non-elective inpatient episodes of people aged ≥75years (all specialties) between October 2014 and October 2015. Pre-admission frailty was assessed with the Clinical Frailty Scale (CFS) of the Canadian Study on Health & Aging, and AIS in the Emergency Department was measured with a Modified Early Warning Score (ED-MEWS<4 was considered as low acuity, and ED-MEWS≥4 as high acuity). A survival analysis compared times to 30-day inpatient death between CFS categories (1-4: very fit to vulnerable, 5: mildly frail, 6: moderately frail, and 7-8: severely or very severely frail).

RESULTS

There were 12,282 non-elective patient episodes (8202 first episodes, of which complete data was available for 5505). In a Cox proportional hazards model controlling for age, gender, Charlson Comorbidity Index, history of dementia, current cognitive concern, and discharging specialty (medical versus surgical), ED-MEWS≥4 (HR=2.87, 95% CI: 2.27-3.62, p<0.001), and CFS 7-8 (compared to CFS 1-4, HR=2.10, 95% CI: 1.52-2.92, p<0.001) were independent predictors of survival time.

CONCLUSIONS

We found frailty and AIS independently associated with inpatient mortality after adjustment for confounders. Hospitals may find it informative to undertake large scale assessment of frailty (vulnerability), as well as AIS (stressor), in older patients admitted to hospital as emergencies.