Predictive powers of the Modified Early Warning Score and the National Early Warning Score in general ward patients who activated the medical emergency team

Indicators of patient deterioration in poorly resourced private hospitals: Which vital sign to watch? A retrospective case-control study

BACKGROUND

Patient vital signs are a measure of wellness if monitored regularly and accurately. Staff shortages in poorly resourced regional hospitals often result in inadequate patient monitoring, putting patients at risk of undetected deterioration.

OBJECTIVE

This study aims to explore the pattern and completeness of vital sign monitoring and the contribution of each vital sign in predicting clinical deterioration events in resource-poor regional/rural hospitals.

METHOD

Using a retrospective case-control study design, we compared 24 h of vital sign data from deteriorating and nondeteriorating patients from two poorly-resourced regional hospitals. Descriptive statistics, t-tests, and analysis of variance are used to compare patient-monitoring frequency and completeness. The contribution of each vital sign in predicting patient deterioration was determined using the Area Under the Receiver Operator Characteristic curve and binary logistical regression analysis.

RESULTS

Deteriorating patients were monitored more frequently (9.58 [7.02] times) in the 24-h period than nondeteriorating patients (4.93 [2.66] times). However, the completeness of vital sign documentation was higher in nondeteriorating (85.2%) than in deteriorating patients (57.7%). Body temperature was the most frequently omitted vital sign. Patient deterioration was positively linked to the frequency of abnormal vital signs and the number of abnormal vital signs per set (Area Under the Receiver Operator Characteristic curve: 0.872 and 0.867, respectively). No single vital sign strongly predicts patient outcomes. However, a supplementary oxygen value of >3 L/min and a heart rate of >139 beats/min were the best predictors of patient deterioration.

CONCLUSION

Given the poor resourcing and often geographical remoteness of small regional hospitals, it is prudent that the nursing staff are made aware of the vital signs that best indicate deterioration for the cohort of patients in their care. Tachycardic patients on supplementary oxygen are at high risk of deterioration.

Patient outcomes following medical emergency team review on general wards: Development of predictive models

AIM

To develop and internally validate risk prediction models for subsequent clinical deterioration, unplanned ICU admission and death among ward patients following medical emergency team (MET) review.

DESIGN

A retrospective cohort study of 1500 patients who remained on a general ward following MET review at an Australian quaternary hospital.

METHOD

Logistic regression was used to model (1) subsequent MET review within 48 h, (2) unplanned ICU admission within 48 h and (3) hospital mortality. Models included demographic, clinical and illness severity variables. Model performance was evaluated using discrimination and calibration with optimism-corrected bootstrapped estimates. Findings are reported using the TRIPOD guideline for multivariable prediction models for prognosis or diagnosis. There was no patient or public involvement in the development and conduct of this study.

RESULTS

Within 48 h of index MET review, 8.3% (n = 125) of patients had a subsequent MET review, 7.2% (n = 108) had an unplanned ICU admission and in-hospital mortality was 16% (n = 240). From clinically preselected predictors, models retained age, sex, comorbidity, resuscitation limitation, acuity-dependency profile, MET activation triggers and whether the patient was within 24 h of hospital admission, ICU discharge or surgery. Models for subsequent MET review, unplanned ICU admission, and death had adequate accuracy in development and bootstrapped validation samples.

CONCLUSION

Patients requiring MET review demonstrate complex clinical characteristics and the majority remain on the ward after review for deterioration. A risk score could be used to identify patients at risk of poor outcomes after MET review and support general ward clinical decision-making.

RELEVANCE TO CLINICAL PRACTICE

Our risk calculator estimates risk for patient outcomes following MET review using clinical data available at the bedside. Future validation and implementation could support evidence-informed team communication and patient placement decisions.

Illness severity characteristics and outcomes of patients remaining on an acute ward following medical emergency team review: a latent profile analysis

BACKGROUND

Patients requiring medical emergency team (MET) review have complex clinical needs, and most remain on the ward after review. Current detection instruments cannot identify post-MET patient requirements, meaning patients remain undistinguished, potentially resulting in missed management opportunities. We propose that deteriorating patients will cluster along dimensions of illness severity and that these clusters may be used to strengthen patient risk management practices.

OBJECTIVE

To identify and define the number of illness severity clusters and report outcomes among ward patients following MET review.

STUDY DESIGN AND SETTING

This retrospective cohort study examined the clinical records of 1500 adult ward patients following MET review at an Australian quaternary hospital. Three-step latent profile analysis methods were used to determine clusters using Sequential Organ Failure Assessment (SOFA) and Nursing Activities Score (NAS) as illness severity indicators. Study outcomes were (1) hospital mortality, (2) unplanned intensive care unit (ICU) admission and (3) subsequent MET review.

RESULTS

Patients were unplanned (73.9%) and medical (57.5%) admissions with at least one comorbidity (51.4%), and complex combinations of acuity (SOFA range 1-17) and dependency (NAS range 22.4%-148.5%). Five clusters are reported. Patients in cluster 1 were equivalent to clinically stable general ward patients. Organ failure and complexity increased with cluster progression-clusters 2 and 3 were equivalent to subspecialty/higher-dependency wards, and clusters 4 and 5 were equivalent to ICUs. Patients in cluster 5 had the greatest odds for death (OR 26.2, 95% CI 23.3 to 31.3), unplanned ICU admission (OR 3.1, 95% CI 3.0 to 3.1) and subsequent MET review (OR 2.4, 95% CI 2.4 to 2.6).

CONCLUSION

The five illness severity clusters may be used to define patients at risk of poorer outcomes who may benefit from enhanced levels of monitoring and targeted care.

Use of the National Early Warning Score for predicting deterioration of patients with acute pulmonary embolism: a post-hoc analysis of the YEARS Study

BACKGROUND

The Pulmonary Embolism Severity Index (PESI) and the simplified PESI (sPESI) are validated scores for mortality prediction in patients with pulmonary embolism (PE). National Early Warning Score (NEWS) is a general prognostic risk score for multiple clinical settings. We investigated whether the NEWS had a comparable performance with the PESI and sPESI, for predicting intensive care unit (ICU) admission and death in patients with acute PE.

METHODS

In haemodynamically stable patients with confirmed PE from the YEARS Study (2013-2015), we evaluated the performance of the NEWS, PESI and sPESI for predicting 7-day ICU admission and 30-day mortality. Receiver operating characteristic curves were plotted and the area under the curve (AUC) was calculated.

RESULTS

Of 352 patients, 12 (3.4%) were admitted to the ICU and 5 (1.4%) died. The AUC of the NEWS for ICU admission was 0.80 (95% CI 0.66 to 0.94) and 0.92 (95% CI 0.82 to 1.00) for 30-day mortality. At a threshold of 3 points, NEWS yielded a sensitivity and specificity of 92% and 53% for ICU admission and 100% and 52% for 30-day mortality. The AUC of the PESI was 0.64 (95% CI 0.48 to 0.79) for ICU admission and 0.94 (95% CI 0.87 to 1.00) for mortality. At a threshold of 66 points, PESI yielded a sensitivity of 75% and a specificity of 38% for ICU admission. For mortality, these were 100% and 37%, respectively. The performance of the sPESI was similar to that of PESI.

CONCLUSION

In comparison with PESI and sPESI, NEWS adequately predicted 7-day ICU admission as well as 30-day mortality, supporting its potential relevance for clinical practice.

Indications and measures of medical emergency teams: a retrospective evaluation of in-hospital emergency operations of the German Resuscitation Register

BACKGROUND

The present study examines characteristics and interventions of medical emergency teams (MET) in in-hospital emergency care.

METHODS

Analysis of all in-hospital emergencies in patients ≥18 years at 62 hospitals with established MET from the database of the German Resuscitation Registry between 2014-2019. The evaluation covered indications for activation using the ABCDE-scheme, time intervals of arrival and patient care as well as the performed invasive/medical interventions.

RESULTS

Out of 62 hospitals 14,166 in-hospital emergencies (male: 8033 [56.7%]; mean age: 64±18 years) were included. Causes of activation were circulation (5760 [40.7%]), disability (4076 [28.8%]), breathing (3649 [25.8%]) and airway-problems (1589 [11.2%]). Average arrival time at the emergency scene was 4±3 minutes, supply time of MET was 24±23 minutes. Endotracheal intubation was required in 1757 (12.4%) and difficult intubation occurred in 201 (11.4%) patients with the necessity for cricothyroidotomy in eight cases (3.9%). Invasive blood-pressure-measurement was indicated in 1074 (7.6%) patients. Catecholamines were required for hemodynamic stabilization in 2421 (17.1%) patients (norepinephrine: 1520 [10.7%], epinephrine: 430 [3.0%], dobutamine: 26 [0.2%]).

CONCLUSIONS

Current in-hospital emergency care requires special skills in invasive hemodynamic and airway interventions. Recommendations from professional societies are necessary to optimize equipment (e.g. videolaryngoscopy, invasive blood pressure management), training, care algorithms and staff composition against the background of an increasing shortage of resources in the healthcare system.

Characteristics and outcomes of medical emergency team calls in a Swiss tertiary centre - a retrospective observational study

AIMS OF THE STUDY

To describe reasons for medical emergency team (MET) activation over time, to analyse outcomes, and to describe the circadian distribution of MET calls and Intensive Care Unit (ICU) admissions following MET activation.

METHODS

Monocentric retrospective observational study of prospectively collected data on all MET calls between 1^st of January 2012 until 31^st of May 2019. We analysed data on baselines, referring wards, and disposition of all MET patients. In addition, we allocated all MET calls to the hourly intervals over the 24-hour cycle of the day in order to identify peak times of team activation.

RESULTS

A total of 4068 calls in 3277 patients (37% female, n = 1210) were analysed. The mean age was 65.9 years (± 15.7). The MET dose (defined as MET calls/1000 hospital admissions) remained relatively stable over the years with a median of 8.0 calls/1000 hospitalisations (interquartile range [IQR] 7.0-10.0). A total of 2526 calls (62%) occurred out of hours (17:00 to 8:00). The hourly rate of MET activations was greatest during the evening shift (33.8% of calls in seven hours), followed by the day shift (35.8% calls in nine hours) and night shift (30.4% in eight hours). Over the years, staff concern was the main reason for a MET call (n = 1192, 34%), followed by low peripheral oxygen saturation (SpO₂) not responding to oxygen therapy (n = 776, 22%). Abnormal respiratory rate was a trigger to call the MET in 44 cases (1.3%), and was not documented prior to 2017. Overall, in-hospital mortality was 22%.

CONCLUSION

While most common reasons for MET calls over the years were staff concern and low SpO₂, abnormal respiratory rate was the least frequent, but increased after the introduction of the quick sequential organ failure assessment (qSOFA) in 2016. Most MET calls occurred out of hours with peak hours during the evening shift, highlighting the importance of resource allocation during this shift when planning to introduce a MET system in a hospital. In-hospital mortality after a MET call was 22%.

Quick Sequential Organ Failure Assessment Score and the Modified Early Warning Score for Predicting Clinical Deterioration in General Ward Patients Regardless of Suspected Infection

BACKGROUND

The quick sequential organ failure assessment (qSOFA) score is suggested to use for screening patients with a high risk of clinical deterioration in the general wards, which could simply be regarded as a general early warning score. However, comparison of unselected admissions to highlight the benefits of introducing qSOFA in hospitals already using Modified Early Warning Score (MEWS) remains unclear. We sought to compare qSOFA with MEWS for predicting clinical deterioration in general ward patients regardless of suspected infection.

METHODS

The predictive performance of qSOFA and MEWS for in-hospital cardiac arrest (IHCA) or unexpected intensive care unit (ICU) transfer was compared with the areas under the receiver operating characteristic curve (AUC) analysis using the databases of vital signs collected from consecutive hospitalized adult patients over 12 months in five participating hospitals in Korea.

RESULTS

Of 173,057 hospitalized patients included for analysis, 668 (0.39%) experienced the composite outcome. The discrimination for the composite outcome for MEWS (AUC, 0.777; 95% confidence interval [CI], 0.770-0.781) was higher than that for qSOFA (AUC, 0.684; 95% CI, 0.676-0.686; P < 0.001). In addition, MEWS was better for prediction of IHCA (AUC, 0.792; 95% CI, 0.781-0.795 vs. AUC, 0.640; 95% CI, 0.625-0.645; P < 0.001) and unexpected ICU transfer (AUC, 0.767; 95% CI, 0.760-0.773 vs. AUC, 0.716; 95% CI, 0.707-0.718; P < 0.001) than qSOFA. Using the MEWS at a cutoff of ≥ 5 would correctly reclassify 3.7% of patients from qSOFA score ≥ 2. Most patients met MEWS ≥ 5 criteria 13 hours before the composite outcome compared with 11 hours for qSOFA score ≥ 2.

CONCLUSION

MEWS is more accurate that qSOFA score for predicting IHCA or unexpected ICU transfer in patients outside the ICU. Our study suggests that qSOFA should not replace MEWS for identifying patients in the general wards at risk of poor outcome.

Patient Deterioration on General Care Units: A Concept Analysis

Patient deterioration is a phenomenon that occurs from the inability to recognize it or respond to a change in condition. Despite the published reports on recognizing a deteriorating patient on general care floors, a gap remains in the ability of nurses to describe the concept, affecting patient outcomes. Walker and Avant's approach was applied to analyze patient deterioration. The aim of this article was to explore and clarify the meaning of patient deterioration and identify attributes, antecedents, and consequences. The defining attributes were compared to early warning scores. An operational definition was developed and its value to nurses established.

Comparison of the National Early Warning Scores and Rapid Emergency Medicine Scores with the APACHE II Scores as a Prediction of Mortality in Patients with Medical Emergency Team Activation: a Single-centre Retrospective Cohort Study

Introduction

The medical emergency team enables the limitation of patients’ progression to critical illness in the general ward. The early warning scoring system (EWS) is one of the criteria for medical emergency team activation; however, it is not a valid criterion to predict the prognosis of patients with MET activation.

Aim

In this study, the National Early Warning Score (NEWS) and Rapid Emergency Medicine Score (REMS) was compared with that of the Acute Physiology and Chronic Health Evaluation II (APACHE II) score in predicting the prognosis of patients who had been treated a medical emergency team.

Material and Methods

In this single-centre retrospective cohort study, patients treated by a medical emergency team between April 2013 and March 2019 and the 28-day prognosis of MET-activated patients were assessed using APACHE II, NEWS, and REMS.

Results

Of the 196 patients enrolled, 152 (77.5%) were men, and 44 (22.5%) were women. Their median age was 68 years (interquartile range: 57-76 years). The most common cause of medical emergency team activation was respiratory failure (43.4%). Univariate analysis showed that APACHE II score, NEWS, and REMS were associated with 28-day prognostic mortality. There was no significant difference in the area under the receiver operating characteristic curve of APACHE II (0.76), NEWS (0.67), and REMS (0.70); however, the sensitivity of NEWS (0.70) was superior to that of REMS (0.47).

Conclusion

NEWS is a more sensitive screening tool like APACHE II than REMS for predicting the prognosis of patients with medical emergency team activation. However, because the accuracy of NEWS was not sufficient compared with that of APACHE II score, it is necessary to develop a screening tool with higher sensitivity and accuracy that can be easily calculated at the bedside in the general ward.

[In-hospital emergency care in the Federal Republic of Germany. A site survey of hospitals in the German Resuscitation Registry]

BACKGROUND

In contrast to prehospital care there is a lack of specifications for the organization and equipment of medical emergency teams for in-hospital emergency care.

OBJECTIVE

Evaluation of the organization, team composition, training, equipment and tasks of medical emergency teams in the Federal Republic of Germany.

MATERIAL AND METHODS

Evaluation of a web-based survey of all hospitals participating in the German Resuscitation Register between February and March2020. The participants were asked about team composition; emergency equipment; type, content and scope of special training or further training as well as other additional tasks in the everyday clinical routine when participating in the medical emergency team. Hospitals with ≤ or >600 beds were compared.

RESULTS

A total of 21 (>600 beds: 10, 48%; ≤600 beds: 11, 52%) hospitals participated in the survey. Team composition requirements were present at 76% (n = 16; ≤600 beds: 8, 72% vs. >600 beds: 8, 80%), training requirements for medical emergency teams at 38% (n = 16; ≤600 beds: 4, 36% vs. >600 beds: 4, 40%) of hospitals, with a focus on cardiac life support (n = 6, 28%; ≤600 beds: 3, 27% vs. >600 beds: 3, 30%) and airway management (n = 4, 19%; ≤600 beds: 3, 27% vs. >600 beds: 1, 10%). A 12-lead electrocardiogram (n = 7, 33%; ≤600 beds: 1, 9% vs. >600 beds: 6, 60%; p = 0.02), video laryngoscope (n = 7, 33%; ≤600 beds: 2, 18% vs. >600 beds: 5, 50%), ventilator without (n = 7, 33%; ≤600 beds: 2, 18% vs. >600 beds: 5, 50%) or with the possibility of non-invasive ventilation was part of the standard equipment in n = 4, 19% (≤600 beds: 1, 9% vs. >600 beds: 3, 30%). A total of 85% (n = 18; ≤600 beds: 10, 100% vs. >600 beds 8, 72%), had additional tasks in the daily clinical routine. While clinics with >600 beds staffed medical emergency teams 100% of the time from the intensive care units, in clinics ≤600 beds medical emergency teams were deployed significantly more often in the emergency department (n = 5, 45%) and in the normal wards (n = 5, 45%, p = 0.03).

CONCLUSION

Training and equipment of medical emergency teams in the Federal Republic of Germany is heterogeneous. They should at least meet the standards commonly used in prehospital emergency medicine and include the availability of a portable 12-lead electrocardiogram, a ventilator with the possibility of noninvasive ventilation and a video laryngoscope. Regardless of the size of the hospital, continuous availability of all members of the medical emergency teams should be ensured.

A physician-led medical emergency team increases the rate of medical interventions: A multicenter study in Korea

BACKGROUND

According to the rapid response system's team composition, responding teams were named as rapid response team (RRT), medical emergency team (MET), and critical care outreach. A RRT is often a nurse-led team, whereas a MET is a physician-led team that mainly plays the role of an efferent limb. As few multicenter studies have focused on physician-led METs, we comprehensively analyzed cases for which physician-led METs were activated.

METHODS

We retrospectively analyzed cases for which METs were activated. The study population consisted of subjects over 18 years of age who were admitted in the general ward from January 2016 to December 2017 in 9 tertiary teaching hospitals in Korea. The data on subjects' characteristics, activation causes, activation methods, performed interventions, in-hospital mortality, and intensive care unit (ICU) transfer after MET activation were collected and analyzed.

RESULTS

In this study, 12,767 cases were analyzed, excluding those without in-hospital mortality data. The subjects' median age was 67 years, and 70.4% of them were admitted to the medical department. The most common cause of MET activation was respiratory distress (35.1%), followed by shock (11.8%), and the most common underlying disease was solid cancer (39%). In 7,561 subjects (59.2%), the MET was activated using the screening system. The commonly performed procedures were arterial line insertion (17.9%), intubation (13.3%), and portable ultrasonography (13.0%). Subsequently, 29.4% of the subjects were transferred to the ICU, and 27.2% died during hospitalization.

CONCLUSIONS

This physician-led MET cohort showed relatively high rates of intervention, including arterial line insertion and portable ultrasonography, and low ICU transfer rates. We presume that MET detects deteriorating patients earlier using a screening system and begins ICU-level management at the patient's bedside without delay, eventually preventing the patient's condition from worsening and transfer to the ICU.

Technical considerations for evaluating clinical prediction indices: a case study for predicting code blue events with MEWS

Objective.There have been many efforts to develop tools predictive of health deterioration in hospitalized patients, but comprehensive evaluation of their predictive ability is often lacking to guide implementation in clinical practice. In this work, we propose new techniques and metrics for evaluating the performance of predictive alert algorithms and illustrate the advantage of capturing the timeliness and the clinical burden of alerts through the example of the modified early warning score (MEWS) applied to the prediction of in-hospital code blue events.Approach. Different implementations of MEWS were calculated from available physiological parameter measurements collected from the electronic health records of ICU adult patients. The performance of MEWS was evaluated using conventional and a set of non-conventional metrics and approaches that take into account the timeliness and practicality of alarms as well as the false alarm burden.Main results. MEWS calculated using the worst-case measurement (i.e. values scoring 3 points in the MEWS definition) over 2 h intervals significantly reduced the false alarm rate by over 50% (from 0.19/h to 0.08/h) while maintaining similar sensitivity levels as MEWS calculated from raw measurements (∼80%). By considering a prediction horizon of 12 h preceding a code blue event, a significant improvement in the specificity (∼60%), the precision (∼155%), and the work-up to detection ratio (∼50%) could be achieved, at the cost of a relatively marginal decrease in sensitivity (∼10%).Significance. Performance aspects pertaining to the timeliness and burden of alarms can aid in understanding the potential utility of a predictive alarm algorithm in clinical settings.

Impact of hospitalization duration before medical emergency team activation: A retrospective cohort study

BACKGROUND

The rapid response system has been implemented in many hospitals worldwide and, reportedly, the timing of medical emergency team (MET) attendance in relation to the duration of hospitalization is associated with the mortality of MET patients. We evaluated the relationship between duration of hospitalization before MET activation and patient mortality. We compared cases of MET activation for early, intermediate, and late deterioration to patient characteristics, activation characteristics, and patient outcomes. We also aimed to determine the relationship, after adjusting for confounders, between the duration of hospitalization before MET activation and patient mortality.

MATERIALS AND METHODS

We retrospectively evaluated patients who triggered MET activation in general wards from March 2009 to February 2015 at the Asan Medical Center in Seoul. Patients were categorized as those with early deterioration (less than 2 days after admission), intermediate deterioration (2-7 days after admission), and late deterioration (more than 7 days after admission) and compared them to patient characteristics, activation characteristics, and patient outcomes.

RESULTS

Overall, 7114 patients were included. Of these, 1793 (25.2%) showed early deterioration, 2113 (29.7%) showed intermediate deterioration, and 3208 (45.1%) showed late deterioration. Etiologies of MET activation were similar among these groups. The clinical outcomes significantly differed among the groups (intensive care unit transfer: 34.1%, 35.6%, and 40.4%; p < 0.001 and mortality: 26.3%, 31.5%, and 41.2%; p < 0.001 for early, intermediate, and late deterioration, respectively). Compared with early deterioration and adjusted for confounders, the odds ratio of mortality for late deterioration was 1.68 (1.46-1.93).

CONCLUSIONS

Nearly 50% of the acute clinically-deteriorating patients who activated the MET had been hospitalized for more than 7 days. Furthermore, they presented with higher rates of mortality and ICU transfer than patients admitted for less than 7 days before MET activation and had mortality as an independent risk factor.