Accuracy in identifying patients with loss of consciousness in a police-operated emergency call centre - first step in the chain of survival

Acute internal medicine physicians' clinical intuition based on acute care telephone referral: A prospective study

INTRODUCTION

In the Netherlands, most emergency department (ED) patients are referred by a general practitioner (GP) or a hospital specialist. Early risk stratification during telephone referral could allow the physician to assess the severity of the patients' illness in the prehospital setting. We aim to assess the discriminatory value of the acute internal medicine (AIM) physicians' clinical intuition based on telephone referral of ED patients to predict short-term adverse outcomes, and to investigate on which information their predictions are based.

METHODS

In this prospective study, we included adult ED patients who were referred for internal medicine by a GP or a hospital specialist. Primary outcomes were hospital admission and triage category according to the Manchester Triage System (MTS). Secondary outcome was 31-day mortality. The discriminatory performance of the clinical intuition was assessed using an area under the receiver operating characteristics curve (AUC). To identify which information is important to predict adverse outcomes, we performed univariate regression analysis. Agreement between predicted and observed MTS triage category was assessed using intraclass and Spearman's correlation.

RESULTS

We included 333 patients, of whom 172 (51.7%) were referred by a GP, 146 (43.8%) by a hospital specialist, and 12 (3.6%) by another health professional. The AIM physician's clinical intuition showed good discriminatory performance regarding hospital admission (AUC 0.72, 95% CI: 0.66-0.78) and 31-day mortality (AUC 0.73, 95% CI: 0.64-0.81). Univariate regression analysis showed that age ≥65 years and a sense of alarm were significant predictors. The predicted and observed triage category were similar in 45.2%, but in 92.5% the prediction did not deviate by more than one category. Intraclass and Spearman's correlation showed fair agreement between predicted and observed triage category (ICC 0.48, Spearman's 0.29).

CONCLUSION

Clinical intuition based on relevant information during a telephone referral can be used to accurately predict short-term outcomes, allowing for early risk stratification in the prehospital setting and managing ED patient flow more effectively.

Symptom-Based Dispatching in an Emergency Medical Communication Centre: Sensitivity, Specificity, and the Area under the ROC Curve

Measuring the performance of emergency medical dispatch tools used in paramedic-staffed emergency medical communication centres (EMCCs) is rarely performed. The objectives of our study were, therefore, to measure the performance and accuracy of Geneva's dispatch system based on symptom assessment, in particular, the performance of ambulance dispatching with lights and sirens (L&S) and to measure the effect of adding specific protocols for each symptom. Methods: We performed a prospective observational study including all emergency calls received at Geneva's EMCC (Switzerland) from 1 January 2014 to 1 July 2019. The risk levels selected during the emergency calls were compared to a reference standard, based on the National Advisory Committee for Aeronautics (NACA) scale, dichotomized to severe patient condition (NACA ≥ 4) or stable patient condition (NACA < 4) in the field. The symptom-based dispatch performance was assessed using a receiver operating characteristic (ROC) curve. Contingency tables and a Fagan nomogram were used to measure the performance of the dispatch with or without L&S. Measurements were carried out by symptom, and a group of symptoms with specific protocols was compared to a group without specific protocols. Results: We found an acceptable area under the ROC curve of 0.7474, 95%CI (0.7448-0.7503) for the 148,979 assessments included in the study. Where the severity prevalence was 21%, 95%CI (20.8-21.2). The sensitivity of the L&S dispatch was 87.5%, 95%CI (87.1-87.8); and the specificity was 47.3%, 95%CI (47.0-47.6). When symptom-specific assessment protocols were used, the accuracy of the assessments was slightly improved. Conclusions: Performance measurement of Geneva's symptom-based dispatch system using standard diagnostic test performance measurement tools was possible. The performance was found to be comparable to other emergency medical dispatch systems using the same reference standard. However, the implementation of specific assessment protocols for each symptom may improve the accuracy of symptom-based dispatch systems.

Data quality of Glasgow Coma Scale and Systolic Blood Pressure in scientific studies involving physician-staffed emergency medical services: Systematic review

BACKGROUND

Emergency physicians on-scene provide highly specialized care to severely sick or injured patients. High-quality research relies on the quality of data, but no commonly accepted definition of EMS data quality exits. Glasgow Coma Score (GCS) and Systolic Blood Pressure (SBP) are core physiological variables, but little is known about the quality of these data when reported in p-EMS research. This systematic review aims to describe the quality of pre-hospital reporting of GCS and SBP data in studies where emergency physicians are present on-scene.

METHODS

A systematic literature search was performed using CINAHL, Cochrane, Embase, Medline, Norart, Scopus, SweMed + and Web of Science, in accordance with the PRISMA guidelines. Reported data on accuracy of reporting, completeness and capture were extracted to describe the quality of documentation of GCS and SBP. External and internal validity assessment was performed by extracting a set of predefined variables.

RESULTS

We included 137 articles describing data collection for GCS, SBP or both. Most studies (81%) were conducted in Europe and 59% of studies reported trauma cases. Reporting of GCS and SBP data were not uniform and may be improved to enable comparisons. Of the predefined external and internal validity data items, 26%-45% of data were possible to extract from the included papers.

CONCLUSIONS

Reporting of GCS and SBP is variable in scientific papers. We recommend standardized reporting to enable comparisons of p-EMS.

Preventable deaths following emergency medical dispatch--an audit study

Background

Call taker triage of calls to the 112 emergency number, can be error prone because rapid decisions must be made based on limited information. Here we investigated the preventability and common characteristics of same-day deaths among patients who called 112 and were not assigned an ambulance with lights and sirens by the Emergency Medical Communication Centre (EMCC).

Methods

An audit was performed by an external panel of experienced prehospital consultant anaesthesiologists. The panel focused exclusively on the role of the EMCC, assessing whether same-day deaths among 112 callers could have been prevented if the EMCC had assessed the situations as highly urgent. The panels’ assessments were based on review of patient charts and voice-log recordings of 112 calls. All patient related material was reviewed by the audit panel and all cases where then scored as preventable, potentially preventable or non-preventable during a two day meeting. The study setting was three of five regions in Denmark with a combined population of 4,182,613 inhabitants, which equals 75% of the Danish population. The study period was 18 months, from mid-2011 to the end of 2012.

Results

Linkage of prospectively collected EMCC data with population-based registries resulted in the identification of 94,488 non-high-acuity 112 callers. Among these callers, 152 (0.16% of all) died on the same day as the corresponding 112 call, and were included in this study. The mean age of included patients was 74.4 years (range, 31–100 years) and 45.4% were female. The audit panel found no definitively preventable deaths; however, 18 (11.8%) of the analysed same-day deaths (0.02% of all non-high-acuity callers) were found to be potentially preventable. In 13 of these 18 cases, the dispatch protocol was either not used or not used correctly.

Conclusion

Same-day death rarely occurred among 112 callers whose situations were assessed as not highly urgent. No same-day deaths were found to be definitively preventable by a different EMCC call assessment, but a minority of same-day deaths could potentially have been prevented with more accurate triage. Better adherence with dispatch protocol could improve the safety of the dispatch process.

Predictability of the Call Triage Protocol to Detect if Dispatchers Should Activate Community First Responders

INTRODUCTION

Shortening response time to an emergency call leads to the success of resuscitation by chest compression and defibrillation. However, response by ambulance or fire truck is not fast enough for resuscitation in Japan. In rural areas, response times can be more than 10 minutes. One possible way to shorten the response time is to establish a system of first responders (eg, police officers or firefighters) who are trained appropriately to perform resuscitation. Another possible way is to use a system of Community First Responders (CFRs) who are trained neighbors. At present, there are no call triage protocols to decide if dispatchers should activate CFRs.

OBJECTIVE

The aim of this study was to determine the predictability to detect if dispatchers should activate CFRs.

METHODS

Two CFR call triage protocols (CFR protocol Ver.0 and Ver.1) were established. The predictability of CFR protocols was examined by comparing the paramedic field reports. From the results of sensitivity of CFR protocol, the numbers of annual CFR activations were calculated. All data were collected, prospectively, for four months from October 1, 2012 through January 31, 2013.

RESULTS

The ROC-AUC values appear slightly higher in CFR protocol Ver.1 (0.857; 95% CI, 79.8-91.7) than in CFR protocol Ver.0 (0.847; 95% CI, 79.0-90.3). The number of annual CFR activations is higher in CFR protocol Ver.0 (7.47) than in CFR protocol Ver.1 (5.45).

CONCLUSION

Two call triage protocols have almost the same predictability as the Medical Priority Dispatch System (MPDS). The study indicates that CFR protocol Ver.1 is better than CFR protocol Ver.0 because of the higher predictability and low number of activations. Also, it indicates that CFRs who are not medical professionals can respond to a patient with cardiac arrest.

Fusion of dispatching centres into one entity: effects on performance

BACKGROUND

Dispatching centres were fused into one of the 112 entity, which caused concerns regarding whether the medical calls could be processed effectively also in the new centre. We evaluated the effects of the reform on key performance criteria in medical calls.

METHODS

This observational study in the Helsinki Dispatching Centre consisted of two periods: Period I 2 years before the reform and Period II 2 years after. The main outcome measures were answering and call processing times, accuracy of risk assessment and appropriate use of ambulances.

RESULTS

In Period I (n=574,276), 92.2% of all incoming phone calls were answered within 10 s and in Period II (n=758,022) 82.8% (P<0.0001). Time to dispatch a first responding fire unit increased from 98 to 113 s (P<0.0001) and an advanced life support unit in category A calls increased from 73 to 84 s (P<0.0001). In Period I 47.7%, 34.8% and 17.5% of phone calls were completed in <3, 3-5 and >5 min and in Period II 29.8%, 36.1% and 34.1% (P<0.0001). The number of three studied non-transportation call types and unnecessary lights-and-siren responses increased significantly (P<0.0001 and 0.0001, respectively). Neither the accuracy of risk assessment in the three studied call types nor the rate of telephone-guided cardiopulmonary resuscitation changed.

CONCLUSIONS

The reform increased the total number of ambulance dispatches, prolonged answering and call processing times and had a negative effect on the appropriate use of ambulances. The accuracy of risk assessment was not affected. Evidence-based data should be the basis for the future as dispatching centre processes are shown to be vulnerable during organisational reforms.

Fire fighters as basic life support responders: a study of successful implementation

BACKGROUND

First responders are recommended as a supplement to the Emergency Medical Services (EMS) in order to achieve early defibrillation. Practical and organisational aspects are essential when trying to implement new parts in the "Chain of Survival"; areas to address include minimizing dispatch time, ensuring efficient and quick communication, and choosing areas with appropriate driving distances. The aim of this study was to implement a system using Basic Life Support (BLS) responders equipped with an automatic external defibrillator in an area with relatively short emergency medical services' response times. Success criteria for implementation was defined as arrival of the BLS responders before the EMS, attachment (and use) of the AED, and successful defibrillation.

METHODS

This was a prospective observational study from September 1, 2005 to December 31, 2007 (28 months) in the city of Aarhus, Denmark. The BLS responder system was implemented in an area up to three kilometres (driving distance) from the central fire station, encompassing approximately 81,500 inhabitants. The team trained on each shift and response times were reduced by choice of area and by sending the alarm directly to the fire brigade dispatcher.

RESULTS

The BLS responders had 1076 patient contacts. The median response time was 3.5 minutes (25th percentile 2.75, 75th percentile 4.25). The BLS responders arrived before EMS in 789 of the 1076 patient contacts (73%). Cardiac arrest was diagnosed in 53 cases, the AED was attached in 29 cases, and a shockable rhythm was detected in nine cases. Eight were defibrillated using an AED. Seven of the eight obtained return of spontaneous circulation (ROSC). Six of the seven obtaining ROSC survived more than 30 days.

CONCLUSION

In this study, the implementation of BLS responders may have resulted in successful resuscitations. On basis of the close corporation between all participants in the chain of survival this project contributed to the first link: short response time and trained personnel to ensure early defibrillation.

Improved survival after an out-of-hospital cardiac arrest using new guidelines

BACKGROUND

An out-of-hospital cardiac arrest (OHCA) is associated with a poor prognosis. We hypothesized that the implementations of 2005 European Resuscitation Council resuscitation guidelines were associated with improved 30-day survival after OHCA.

METHODS

We prospectively recorded data on all patients with OHCA treated by the Mobile Emergency Care Unit of Copenhagen in two periods: 1 June 2004 until 31 August 2005 (before implementation) and 1 January 2006 until 31 March 2007 (after implementation), separated by a 4-month period in which the above-mentioned change took place.

RESULTS

We found that 30-day survival increased after the implementation from 31/372 (8.3%) to 67/419 (16%), P=0.001. ROSC at hospital admission, as well as survival to hospital discharge, were obtained in a significantly higher proportion from 23.4% to 39.1%, P<0.0001, and from 7.9% to 16.3%, P=0.0004, respectively. Treatment after implementation was confirmed as a significant predictor of better 30-day survival in a logistic regression analysis.

CONCLUSION

The implementation of new resuscitation guidelines was associated with improved 30-day survival after OHCA.