Effectiveness of Early Warning Scores for Early Severity Assessment in Outpatient Emergency Care: A Systematic Review

Long-term effects of a prehospital telemedicine system on structural and process quality indicators of an emergency medical service

The benefits of a telemedical support system for prehospital emergency medical services include high-level emergency medical support at the push of a button: delegation of drug administration, diagnostic assistance, initiation of therapeutic measures, or choice of hospital destination. At various European EMS sites telemedical routine systems are shortly before implementation. The aim of this study was to investigate the long-term effects of implementing a tele-EMS system on the structural and procedural quality indicators and therefore performance of an entire EMS system. This retrospective study included all EMS missions in Aachen city between 2015 and 2021. Regarding structural indicators of the EMS system, we investigated the overall number of emergency missions with tele-EMS and onsite EMS physicians. Furthermore, we analyzed the distribution of tracer diagnosis and process quality with respect to the time spans on the scene, time until teleconsultation, duration of teleconsultation, prehospital engagement time, and number of simultaneous teleconsultations. During the 7-year study period, 229,384 EMS missions were completed. From 2015 to 2021, the total number of EMS missions increased by 8.5%. A tele-EMS physician was consulted on 23,172 (10.1%) missions. The proportion of telemedicine missions increased from 8.6% in 2015 to 12.9% in 2021. Teleconsultations for missions with tracer diagnoses decreased during from 43.7% to 30.7%, and the proportion of non-tracer diagnoses increased from 56.3% to 69.3%. The call duration for teleconsultation decreased from 12.07 min in 2015 to 9.42 min in 2021. For every fourth mission, one or more simultaneous teleconsultations were conducted by the tele-EMS physician on duty. The implementation and routine use of a tele-EMS system increased the availability of onsite EMS physicians and enabled immediate onsite support for paramedics. Parallel teleconsultations, reduction in call duration, and increase in ambulatory onsite treatments over the years demonstrate the increasing experience of paramedics and tele-EMS physicians with the system in place. A prehospital tele-EMS system is important for mitigating the current challenges in the prehospital emergency care sector.

Diagnostic accuracy of early warning system scores in the prehospital setting

The utilisation of pre-hospital early warning scores in ambulance services is widely endorsed to promptly identify patients at risk of clinical deterioration. Early warning scores enable clinicians to estimate risk based on clinical observations and vital signs, with higher scores indicating an elevated risk of adverse outcomes. Local healthcare systems establish threshold values for these scores to guide clinical decision-making, triage, and response, necessitating a careful balance between identifying critically unwell patients and managing the challenge of prioritisation. Given the limited evidence for optimal early warning scores in emergency department and pre-hospital care settings, a systematic review by Guan et al. (2022) was undertaken to assess the diagnostic accuracy of early warning scores for predicting in-hospital deterioration when applied in the emergency department or pre-hospital setting. This commentary aims to critically appraise the methods used within the review Guan et al (2022) and expand upon the findings in the context of clinical practice.

Development and validation of the early warning system scores ontology

BACKGROUND

Clinical early warning scoring systems, have improved patient outcomes in a range of specializations and global contexts. These systems are used to predict patient deterioration. A multitude of patient-level physiological decompensation data has been made available through the widespread integration of early warning scoring systems within EHRs across national and international health care organizations. These data can be used to promote secondary research. The diversity of early warning scoring systems and various EHR systems is one barrier to secondary analysis of early warning score data. Given that early warning score parameters are varied, this makes it difficult to query across providers and EHR systems. Moreover, mapping and merging the parameters is challenging. We develop and validate the Early Warning System Scores Ontology (EWSSO), representing three commonly used early warning scores: the National Early Warning Score (NEWS), the six-item modified Early Warning Score (MEWS), and the quick Sequential Organ Failure Assessment (qSOFA) to overcome these problems.

METHODS

We apply the Software Development Lifecycle Framework-conceived by Winston Boyce in 1970-to model the activities involved in organizing, producing, and evaluating the EWSSO. We also follow OBO Foundry Principles and the principles of best practice for domain ontology design, terms, definitions, and classifications to meet BFO requirements for ontology building.

RESULTS

We developed twenty-nine new classes, reused four classes and four object properties to create the EWSSO. When we queried the data our ontology-based process could differentiate between necessary and unnecessary features for score calculation 100% of the time. Further, our process applied the proper temperature conversions for the early warning score calculator 100% of the time.

CONCLUSIONS

Using synthetic datasets, we demonstrate the EWSSO can be used to generate and query health system data on vital signs and provide input to calculate the NEWS, six-item MEWS, and qSOFA. Future work includes extending the EWSSO by introducing additional early warning scores for adult and pediatric patient populations and creating patient profiles that contain clinical, demographic, and outcomes data regarding the patient.

Modified Sequential Organ Failure Assessment Score vs. Early Warning Scores in Prehospital Care to Predict Major Adverse Cardiac Events in Acute Cardiovascular Disease

(1) Background: The Modified Sequential Organ Failure Assessment (mSOFA) is an Early Warning Score (EWS) that has proven to be useful in identifying patients at high risk of mortality in prehospital care. The main objective of this study was to evaluate the predictive validity of prehospital mSOFA in estimating 2- and 90-day mortality (all-cause) in patients with acute cardiovascular diseases (ACVD), and to compare this validity to that of four other widely-used EWS. (2) Methods: We conducted a prospective, observational, multicentric, ambulance-based study in adults with suspected ACVD who were transferred by ambulance to Emergency Departments (ED). The primary outcome was 2- and 90-day mortality (all-cause in- and out-hospital). The discriminative power of the predictive variable was assessed and evaluated by the area under the curve (AUC) of the receiver operating characteristic (ROC). (3) Results: A total of 1540 patients met the inclusion criteria. The 2- and 90-day mortality rates were 5.3% and 12.7%, respectively. The mSOFA showed the highest AUC of all the evaluated scores for both 2- and 90-day mortality, AUC = 0.943 (0.917-0.968) and AUC = 0.874 (0.847-0.902), respectively. (4) Conclusions: The mSOFA is a quick and easy-to-use EWS with an excellent ability to predict mortality at both 2 and 90 days in patients treated for ACVD, and has proved to be superior to the other EWS evaluated in this study.