Development and inter-rater reliability of a simple prehospital mobility score for use in emergency patients

BACKGROUND

Mobility assessment enhances the ability of vital sign-based early warning scores to predict risk. Currently mobility is not routinely assessed in a standardized manner in Denmark during the ambulance transfer of unselected emergency patients. The aim of this study was to develop and test the inter-rater reliability of a simple prehospital mobility score for pre-hospital use in ambulances and to test its inter-rater reliability.

METHOD

Following a pilot study, we developed a 4-level prehospital mobility score based of the question"How much help did the patient need to be mobilized to the ambulance trolley". Possible scores were no-, a little-, moderate-, and a lot of help. A cross-sectional study of inter-rater agreement among ambulance personnel was then carried out. Paramedics on ambulance runs in the North- and Central Denmark Region, as well as The Fareoe Islands, were included as a convenience sample between July 2020-May 2021. The simple prehospital mobility score was tested, both by the paramedics in the ambulance and by an additional observer. The study outcomes were inter-rater agreements by weighted kappa between the paramedics and between observers and paramedics.

RESULTS

We included 251 mobility assessments where the patient mobility was scored. Paramedics agreed on the mobility score for 202 patients (80,5%). For 47 (18.7%), there was a deviation of one between scores, in two (< 1%) there was a deviation of two and none had a deviation of three (Table 1). Inter-rater agreement between paramedics in all three regions showed a kappa-coefficient of 0.84 (CI 95%: 0.79;0.88). Between observers and paramedics in North Denmark Region and Faroe Islands the kappa-coefficient was 0.82 (CI 95%: 0.77;0.86).

CONCLUSION

We developed a simple prehospital mobility score, which was feasible in a prehospital setting and with a high inter-rater agreement between paramedics and observers.

A classification system for identifying patients dead on ambulance arrival: a prehospital medical record review

BACKGROUND

Patients dead before arrival of the ambulance or before arrival at hospital may be in- or excluded in mortality analyses, making comparison of mortality difficult. Often only physicians are allowed to declare death, thereby impeding uniform registration of prehospital death. Many studies do not report detailed definitions of prehospital mortality. Our aim was to define criteria to identify and categorize prehospital patients' vital status, and to estimate the proportion of these groups, primarily the proportion of patients dead on ambulance arrival.

METHODS

Prehospital medical records review for patients receiving an ambulance in the North Denmark Region from 2019 to 2021 and registered dead on the same or the following day. We defined three vital status categories: (1) Dead on Ambulance Arrival (DOAA), (2) Out-of-Hospital Cardiac Arrest (OHCA) divided into OHCA Basic Life Support (OHCA BLS) and OHCA Advanced treatment, and 3) Alive on Ambulance Arrival.

RESULTS

Among 3 174 dead patients, DOAA constituted 28.8%, OHCA BLS 13.4%, OHCA Advanced treatment 31.3%, and Alive on Ambulance Arrival 26.6%.

CONCLUSION

We defined exhaustive and mutually exclusive criteria to define vital status, DOAA, OHCA, and Alive on Ambulance Arrival based on prehospital medical records. More than one out of four patients receiving an ambulance and registered dead on the same or the following day were dead already at ambulance arrival. Adding OHCA BLS where resuscitation was terminated without defibrillation or other treatment, increased the proportion of patients dead on ambulance arrival to 42%. We recommend reporting similar categories of vital status to improve valid comparisons of prehospital mortality rates.

Critically deviating vital signs among patients with non-specific diagnoses-A register-based historic cohort study

BACKGROUND

One third of ambulance patients receive non-specific diagnoses in hospital. Mortality is 3-4%, however due to the high patient volume this group accounts for 20% of all deaths at day 30. Non-specific diagnoses do not provide much information on causes for death. Vital signs at first contact with ambulance personnel can act as a proxy for the patient's condition. Thus, we aimed to describe the prevalence of abnormal vital signs, as determined by a modified NEWS2, in ambulance patients who received a non-specific hospital diagnosis. Secondly, we examined the association between vital signs, NEWS2 scores, type of non-specific diagnosis, and mortality among these patients.

METHODS

Register-based historic cohort study of ambulance patients aged 16+ in the North Denmark Region during 2012-2016, who received a non-specific diagnosis (ICD-10 chapters R or Z) at hospital. We used NEWS2 scores to determine if first vital signs were normal or deviating (including critical). Mortality was estimated with the Kaplan-Meier estimator. Association between vital signs and mortality was evaluated by logistic regression.

RESULTS

We included 41,539 patients, 20.9% (N = 8,691) had normal vital signs, 16.3% (N = 6,766) had incomplete vital sign registration, 62.8% (N = 26,082) had deviating vital signs, and of these 6.8% (N = 1,779) were critical. If vital signs were incompletely registered or deviating, mortality was higher compared to normal vital signs. Patients with critical vital signs displayed the highest crude 48-hour and 30-day mortality (7.0% (5.9-8.3) and 13.4% (11.9-15.1)). Adjusting for age, sex, and comorbidity did not change that pattern. Across all vital sign groups, despite severity, the most frequent diagnosis assigned was Z039 observation for suspected disease or condition unspecified.

CONCLUSIONS

Most ambulance patients with non-specific diagnoses had normal or non-critical deviating vital signs and low mortality. Around 4% had critical vital signs and high mortality, not explained by age or comorbidity.

Prehospital Early Warning Scores to Predict Mortality in Patients Using Ambulances

IMPORTANCE

Early warning scores (EWSs) are designed for in-hospital use but are widely used in the prehospital field, especially in select groups of patients potentially at high risk. To be useful for paramedics in daily prehospital clinical practice, evaluations are needed of the predictive value of EWSs based on first measured vital signs on scene in large cohorts covering unselected patients using ambulance services.

OBJECTIVE

To validate EWSs' ability to predict mortality and intensive care unit (ICU) stay in an unselected cohort of adult patients who used ambulances.

DESIGN, SETTING, AND PARTICIPANTS

This prognostic study conducted a validation based on a cohort of adult patients (aged ≥18 years) who used ambulances in the North Denmark Region from July 1, 2016, to December 31, 2020. EWSs (National Early Warning Score 2 [NEWS2], modified NEWS score without temperature [mNEWS], Quick Sepsis Related Organ Failure Assessment [qSOFA], Rapid Emergency Triage and Treatment System [RETTS], and Danish Emergency Process Triage [DEPT]) were calculated using first vital signs measured by ambulance personnel. Data were analyzed from September 2022 through May 2023.

MAIN OUTCOMES AND MEASURES

The primary outcome was 30-day-mortality. Secondary outcomes were 1-day-mortality and ICU admission. Discrimination was assessed using area under the receiver operating characteristic curve (AUROC) and area under the precision recall curve (AUPRC).

RESULTS

There were 107 569 unique patients (52 650 females [48.9%]; median [IQR] age, 65 [45-77] years) from the entire cohort of 219 323 patients who used ambulance services, among whom 119 992 patients (54.7%) had called the Danish national emergency number. NEWS2, mNEWS, RETTS, and DEPT performed similarly concerning 30-day mortality (AUROC range, 0.67 [95% CI, 0.66-0.68] for DEPT to 0.68 [95% CI, 0.68-0.69] for mNEWS), while qSOFA had lower performance (AUROC, 0.59 [95% CI, 0.59-0.60]; P vs other scores < .001). All EWSs had low AUPRCs, ranging from 0.09 (95% CI, 0.09-0.09) for qSOFA to 0.14 (95% CI, 0.13-0.14) for mNEWS.. Concerning 1-day mortality and ICU admission NEWS2, mNEWS, RETTS, and DEPT performed similarly, with AUROCs ranging from 0.72 (95% CI, 0.71-0.73) for RETTS to 0.75 (95% CI, 0.74-0.76) for DEPT in 1-day mortality and 0.66 (95% CI, 0.65-0.67) for RETTS to 0.68 (95% CI, 0.67-0.69) for mNEWS in ICU admission, and all EWSs had low AUPRCs. These ranged from 0.02 (95% CI, 0.02-0.03) for qSOFA to 0.04 (95% CI, 0.04-0.04) for DEPT in 1-day mortality and 0.03 (95% CI, 0.03-0.03) for qSOFA to 0.05 (95% CI, 0.04-0.05) for DEPT in ICU admission.

CONCLUSIONS AND RELEVANCE

This study found that EWSs in daily clinical use in emergency medical settings performed moderately in the prehospital field among unselected patients who used ambulances when assessed based on initial measurements of vital signs. These findings suggest the need of appropriate triage and early identification of patients at low and high risk with new and better EWSs also suitable for prehospital use.

Decision on non-conveyance of patients suspected of COVID-19 in a novel arrangement with assessment visits by paramedics at home

BACKGROUND

During the first weeks of the outbreak of the coronavirus disease 2019 (COVID-19), the North Denmark emergency medical services authorised paramedics to assess patients suspected of COVID-19 at home, and then decide if conveyance to a hospital was required. The aim of this study was to describe the cohort of patients who were assessed at home and their outcomes in terms of subsequent hospital visits and short-term mortality.

METHODS

This was a historical cohort study in the North Denmark Region with consecutive inclusion of patients suspected of COVID-19 who were referred to a paramedic's assessment visit by their general practitioner or an out-of-hours general practitioner. The study was conducted from 16 March to 20 May 2020. The outcomes were the proportion of non-conveyed patients who subsequently visited a hospital within 72 hours of the paramedic's assessment visit and mortality at 3, 7 and 30 days. Mortality was estimated using a Poisson regression model with robust variance estimation.

RESULTS

During the study period, 587 patients with a median age of 75 (IQR 59-84) years were referred to a paramedic's assessment visit. Three of four patients (76.5%, 95% CI 72.8;79.9) were non-conveyed, and 13.1% (95% CI 10.2;16.6) of the non-conveyed patients were subsequently referred to a hospital within 72 hours of the paramedic's assessment visit. Within 30 days from the paramedic's assessment visit, mortality was 11.1% [95% CI 6.9;17.9] among patients directly conveyed to a hospital and 5.8% [95% CI 4.0;8.5] among non-conveyed patients. Medical record review revealed that deaths in the non-conveyed group had happened among patients with 'do-not-resuscitate' orders, palliative care plans, severe comorbidities, age ≥ 90 years or nursing home residents.

CONCLUSIONS

The majority (87%) of the non-conveyed patients did not visit a hospital for the following three days after a paramedic's assessment visit. The study implies that this newly established prehospital arrangement served as a kind of gatekeeper for the region's hospitals in regard to patients suspected of COVID-19. The study also demonstrates that implementation of non-conveyance protocols should be accompanied by careful and regular evaluation to ensure patient safety.

More emergency patients presenting with chest pain

INTRODUCTION

Throughout recent years the demand for prehospital emergency care has increased significantly. Non-traumatic chest pain is one of the most frequent complaints. Our aim was to investigate the trend in frequency of the most urgent ambulance patients with chest pain, subsequent acute myocardial infarction (AMI) diagnoses, and 48-hour and 30-day mortality of both groups.

METHODS

Population-based historic cohort study in the North Denmark Region during 2012-2018 including chest pain patients transported to hospital by highest urgency level ambulance following a 1-1-2 emergency call. Primary diagnoses (ICD-10) were retrieved from the regional Patient Administrative System, and descriptive statistics (distribution, frequency) performed. We evaluated time trends using linear regression, and mortality (48 hours and 30 days) was assessed by the Kaplan Meier estimator.

RESULTS

We included 18,971 chest pain patients, 33.9% (n = 6,430) were diagnosed with"Diseases of the circulatory system" followed by the non-specific R- (n = 5,288, 27.8%) and Z-diagnoses (n = 3,634; 19.2%). AMI was diagnosed in 1,967 patients (10.4%), most were non-ST-elevation AMI (39.7%). Frequency of chest pain patients and AMI increased 255 and 22 patients per year respectively, whereas the AMI proportion remained statistically stable, with a tendency towards a decrease in the last years. Mortality at 48 hours and day 30 in chest pain patients was 0.7% (95% CI 0.5% to 0.8%) and 2.4% (95% CI 2.1% to 2.6%).

CONCLUSIONS

The frequency of chest pain patients brought to hospital during 2012-2018 increased. One-tenth were diagnosed with AMI, and the proportion of AMI patients was stable. Almost 1 in of 4 high urgency level ambulances was sent to chest pain patients. Only 1 of 10 patients with chest pain had AMI, and overall mortality was low. Thus, monitoring the number of chest pain patients and AMI diagnoses should be considered to evaluate ambulance utilisation and triage.

Prevalence and mortality among patients with COPD hospitalised by ambulance in the 2007-2018 period

INTRODUCTION

Severe exacerbations in chronic obstructive pulmonary disease (COPD) may require acute medical attention by calling the emergency medical services (EMS) for an ambulance. The 30-day mortality for EMS patients with respiratory diseases appears to have stagnated, which may be due to changes in age, comorbidity or disease severity. We examined trends of occurrence, severity and mortality for EMS patients with COPD.

METHODS

A historical population-based cohort study was conducted encompassing patients with COPD who requested an ambulance in the North Denmark Region in the 2007-2018 period. We described acute severity by oxygen saturation and respiratory rate at the arrival of the ambulance along with comorbidity and duration of hospitalisation.

RESULTS

A total of 5,969 EMS patients with COPD were identified and the figure nearly doubled from 2007 to 2018. Age and comorbidity were higher in the last part of the period. Furthermore, the initial respiratory rate was higher, oxygen saturation was lower and the duration of hospitalisation was lower in the last part of the period. The 30-day mortality rose from 12.6% to 15.4%, but the odds ratio was not statistically higher and decreased after adjustment.

CONCLUSIONS

COPD constituted increasing proportions of those admitted to hospital after calling the EMS. The mortality among EMS patients with COPD may be due to patients being older, having more comorbidities or being more severely acutely ill. The mortality suggests that COPD patients requesting an ambulance should be considered severely ill.

FUNDING

none.

TRIAL REGISTRATION

not relevant.

Prehospital Release of Patients After Treatment in an Anesthesiologist-Staffed Mobile Emergency Care Unit

IMPORTANCE

Prehospital treatment and release of patients may reduce unnecessary transports to the hospital and may improve patient satisfaction. However, the safety of patients should be paramount.

OBJECTIVE

To determine the extent of unplanned emergency department (ED) contacts, short-term mortality, and diagnostic patterns in patients treated and released by a prehospital anesthesiologist supervising a mobile emergency care unit (MECU).

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used a manual review of prehospital and in-hospital medical records to investigate all living patients who were treated and released by an MECU in Odense, Denmark, between January 1, 2011, and December 31, 2020. Patients were followed up for 30 days after initial contact with the prehospital service.

MAIN OUTCOMES AND MEASURES

Primary outcome measures included unplanned contacts with the emergency department less than 48 hours after prehospital treatment and prehospital assigned diagnosis. Secondary outcomes consisted of mortality at 48 hours and 7 and 30 days.

RESULTS

A total of 3141 patients were identified; 384 were excluded and 2757 were included in the analysis. The median patient age was 40 (IQR, 14-66) years; 1296 (47.0%) were female and 1461 (53.0%) were male. Two hundred thirty-nine patients (8.7% [95% CI, 7.6%-9.8%]) had unplanned contact with the ED within 48 hours; this rate was doubled for patients with respiratory diseases (37 of 248 [14.9% (95% CI, 10.7%-20.0%)]). Fifty-nine of 60 patients who died within 48 hours of release had terminal illness. Excluding these patients, the mortality rates were 0.04% at 48 hours, 0.8% at 7 days, and 2.4% at 30 days. Two thousand sixty-one patients (74.8%) had primarily nondefinitive observational diagnoses.

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that prehospital treatment and subsequent release at the scene is safe. One patient in 12 attended the ED within the ensuing 48 hours. However, for patients with respiratory diseases, this rate was doubled. Hospital admission could be avoided for some patients in the end stage of a terminal illness.

How Patients Who Are Transported by Ambulance Experience Dyspnea and the Use of a Dyspnea Scale: A Qualitative Study

Approximately 7% of all dispatched ambulances in Denmark are for patients for whom breathing difficulties are the main cause for using ambulance services. Objective measurements are routinely carried out in the ambulances, but little is known of the patients’ subjective experience of dyspnea. The purpose of this study was to investigate how patients with acute dyspnea, transported to hospital by ambulance, experience their situation, along with their experience of the use of a dyspnea scale. The study was carried out in the North Denmark Region. Transcribed patient interviews and field notes were analyzed and interpreted with inspiration from Paul Ricoeur. For interviews, we included 12 patients with dyspnea who were transported to the hospital by ambulance: six women and six men all aged 60 years or above. Observations were made over six ambulance transports related to dyspnea. Three themes emerged: “anxiety”, “reassurance in the ambulance” and “acceptance of the dyspnea measurements in the ambulance”. Several patients expressed anxiety due to their dyspnea, which was substantiated by observations in the ambulance. The patients expressed different perspectives on what improved the situation (treatment, reassurance by ambulance professionals). The patients and the ambulance personnel were, in general, in favor of the dyspnea scale.

Nationwide study on trends in unplanned hospital attendance and deaths during the 7 weeks after the onset of the COVID-19 pandemic in Denmark

BACKGROUND

The impact of a pandemic on unplanned hospital attendance has not been extensively examined. The aim of this study is to report the nationwide consequences of the COVID-19 pandemic on unplanned hospital attendances in Denmark for 7 weeks after a 'shelter at home' order was issued.

METHODS

We merged data from national registries (Civil Registration System and Patient Registry) to conduct a study of unplanned (excluding outpatient visits and elective surgery) hospital-based healthcare and mortality of all Danes. Using data for 7 weeks after the 'shelter at home' order, the incidence rate of unplanned hospital attendances per week in 2020 was compared with corresponding weeks in 2017-2019. The main outcome was hospital attendances per week as incidence rate ratios. Secondary outcomes were general population mortality and risk of death in-hospital, reported as weekly mortality rate ratios (MRRs).

RESULTS

From 2 438 286 attendances in the study period, overall unplanned attendances decreased by up to 21%; attendances excluding COVID-19 were reduced by 31%; non-psychiatric by 31% and psychiatric by 30%. Out of the five most common diagnoses expected to remain stable, only schizophrenia and myocardial infarction remained stable, while chronic obstructive pulmonary disease exacerbation, hip fracture and urinary tract infection fell significantly. The nationwide general population MRR rose in six of the recorded weeks, while MRR excluding patients who were COVID-19 positive only increased in two.

CONCLUSION

The COVID-19 pandemic and a governmental national 'shelter at home' order was associated with a marked reduction in unplanned hospital attendances with an increase in MRR for the general population in two of 7 weeks, despite exclusion of patients with COVID-19. The findings should be taken into consideration when planning for public information campaigns.

Which symptoms pose the highest risk in patients calling for an ambulance? A population-based cohort study from Denmark

BACKGROUND

Emergency medical service patients are a vulnerable population and the risk of mortality is considerable. In Denmark, healthcare professionals receive 112-emergency calls and assess the main reason for calling. The main aim was to investigate which of these reasons, i.e. which symptoms or mechanism of injury, contributed to short-term risk of death. Secondary aim was to study 1-30 day-mortality for each symptom/ injury.

METHODS

Historic population-based cohort study of emergency medical service patients calling 112 in the North Denmark Region between 01.01.2016-31.12.2018. We defined 1-day mortality as death on the same or the following day. The frequency of each symptom and cumulative number of deaths on day 1 and 30 together with 1- and 30-day mortality for each symptom/mechanism of injury is presented in proportions. Poisson regression with robust variance estimation was used to estimate incident rates (IR) of mortality with 95% confidence intervals (CI), crude and age and sex adjusted, mortality rates on day 1 per 100,000 person-year in the population.

RESULTS

The five most frequent reasons for calling 112 were "chest pain" (15.9%), "unclear problem" (11.9%), "accidents" (11.2%), "possible stroke" (10.9%), and "breathing difficulties" (8.3%). Four of these contributed to the highest numbers of deaths: "breathing difficulties" (17.2%), "unclear problem" (13.2%), "possible stroke" (8.7%), and "chest pain" (4.7%), all exceeded by "unconscious adult - possible cardiac arrest" (25.3%). Age and sex adjusted IR of mortality per 100,000 person-year was 3.65 (CI 3.01-4.44) for "unconscious adult - possible cardiac arrest" followed by "breathing difficulties" (0.45, CI 0.37-0.54), "unclear problem"(0.30, CI 0.11-0.17), "possible stroke"(0.13, CI 0.11-0.17) and "chest pain"(0.07, CI 0.05-0.09).

CONCLUSION

In terms of risk of death on the same day and the day after the 112-call, "unconscious adult/possible cardiac arrest" was the most deadly symptom, about eight times more deadly than "breathing difficulties", 12 times more deadly than "unclear problem", 28 times more deadly than "possible stroke", and 52 times more deadly than "chest pain". "Breathing difficulties" and "unclear problem" as presented when calling 112 are among the top three contributing to short term deaths when calling 112, exceeding both stroke symptoms and chest pain.

Understanding the Effect of Electronic Prehospital Medical Records in Ambulances: A Qualitative Observational Study in a Prehospital Setting

Little is known of ambulance professionals’ work practices regarding the use of medical records, their communication with patients, before and during hand over to Emergency Departments (ED). An electronic Prehospital Medical Record (ePMR) has been implemented in all Danish ambulances since 2015. Our aim was to investigate the use of ePMR and whether it affected the ambulance professionals’ clinical practice. We performed a qualitative study with observations of ePMR use in ambulance runs in the North Denmark Region. Furthermore, informal interviews with ambulance professionals was performed. Analysis was accomplished with inspiration from grounded theory. Our main findings were: (1) the ePMR is an essential work tool which aided ambulance professionals with overview of data collection and facilitated a checklist for ED hand overs, (2) mobility and flexibility of the ePMR facilitated conversations and relations with the patients, and (3) in acute severe situations, the ePMR could not stand alone in hand over or communication with the ED. The ePMR affected the ambulance professionals’ work practice in various ways and utilization of ePMR while simultaneously treating patients in ambulances does not obstruct the relation with the patient. To this end, the ePMR appears feasible in collaboration across the prehospital setting.

Predicting outcome for ambulance patients with dyspnea: a prospective cohort study

OBJECTIVE

To validate the discrimination and classification accuracy of a novel acute dyspnea scale for identifying outcomes of out-of-hospital patients with acute dyspnea.

METHODS

Prospective observational population-based study in the North Denmark Region. We included patients from July 1, 2017 to September 24, 2019 assessed as having acute dyspnea by the emergency dispatcher or by emergency medical services (EMS) personnel. Patients rated dyspnea using the 11-point acute dyspnea scale. The primary outcomes were hospitalization >2 days, ICU admission within 48 hours of ambulance run, and 30-day mortality. We used 5-fold cross-validation and area under receiver operating curves (AUC) to assess predictive properties of the acute dyspnea scale score alone and combined with vital data, age, and sex.

RESULTS

We included 3144 EMS patients with reported dyspnea. Median acute dyspnea scale score was 7 (interquartile range 5 to 8). The outcomes were: 1966 (63%) hospitalized, 164 (5%) ICU stay, and 224 (9%) died within 30 days of calling the ambulance. The acute dyspnea scale score alone showed poor discrimination for hospitalization (AUC 0.56, 95% confidence intervals: 0.54-0.58), intensive care unit admission (0.58, 0.53-0.62), and mortality (0.46, 0.41-0.50). Vital signs (respiratory rate, blood oxygen saturation, blood pressure, and heart rate) showed similarly poor discrimination for all outcomes. The combination of [vital signs + acute dyspnea scale score] showed better discrimination for hospitalization, ICU admission, and mortality (AUC 0.71-0.72). Patients not able to report an acute dyspnea scale score worse outcomes on all parameters.

CONCLUSION

The dyspnea scale showed poor accuracy and discrimination when predicting hospitalization, stay at intensive care unit, and mortality on its own. However, the dyspnea scale may be beneficial as performance measure and indicator of out-of-hospital care.

Patient experience of severe acute dyspnoea and relief during treatment in ambulances: a prospective observational study

Background

Acute dyspnoea is common among ambulance patients, but little is known of the patients’ experience of symptom. We aimed to investigate ambulance patients initial perceived intensity of acute dyspnoea, and whether they experienced relief during prehospital treatment. Furthermore, to investigate the validity and feasibility of using a subjective dyspnoea score in the ambulance, and its association with objectively measured vital signs.

Methods

We performed a prospective observational study in the North Denmark Region from 1. July 2017 to 30. March 2019. We studied patients over the age of 18 to whom an ambulance was dispatched. Patients with acute dyspnoea assessed either at the emergency call or by ambulance professionals on scene were included. Patients were asked to assess dyspnoea on a 0 to 10 verbal numeric rating scale at the primary contact with the ambulance personnel and immediately before release at the scene or arrival at the hospital. Patients received usual prehospital medical treatment. We used visual inspection and Wilcoxon matched-pairs signed-ranks test, to assess dyspnoea scores and change hereof. Scatterplots and linear regression analyses were used to assess associations between the dyspnoea score and vital signs.

Results

We included 3199 patients with at least one dyspnoea score. Of these, 2219 (69%) had two registered dyspnoea scores. The initial median dyspnoea score for all patients was median 8 (interquartile range 6–10). In 1676 (76%) of patients with two scores, the first score decreased from 8 (6–9) to 4 (2–5) during prehospital treatment. The score was unchanged for 370 (17%) and increased for 51 (2%) patients. Higher respiratory rate, blood pressure, and heart rate was seen with higher dyspnoea scores whereas blood oxygen saturation lowered.

Conclusions

We found that acute dyspnoea scored by ambulance patients, was high on a verbal numerical rating scale but decreased before arrival at hospital, suggesting relief of symptoms. The acute dyspnoea score was statistically associated with vital signs, but of limited clinical relevance; this stresses the importance of patients’ experience of symptoms. To this end, the dyspnoea scale appears feasible in the prehospital setting.

Completeness in the recording of vital signs in ambulances increases over time

INTRODUCTION

In 2006, the North Denmark Region implemented the electronic prehospital patient medical record (PPR), amPHI, in the region's prehospital emergency medical service. In 2015, a new nationwide version was implemented. Our aim was to investigate the completeness and correctness of registrations of vital sign data in the PPR after the initial introduction and after the implementation of the new PPR version.

METHODS

This was a descriptive registry-based study including patients to whom an ambulance was dispatched after an emergency call in the North Denmark Region in the periods 2007-2014 and 2016-2017. We examined vital sign data defined as blood pressure (BP), heart rate (HR), blood oxygen saturation (SpO2), respiratory rate (RR), Glasgow Coma Scale (GCS) score and numeric rating scale (NRS) for pain. 
We defined incorrect vital sign values according to clinical plausibility. We used a trend analysis and Pearson's χ2.

RESULTS

We included 253,169 PPRs. The proportion of PPR with registration of vital signs from 2007-2014 compared with 2016-2017 was BP: 73-86%, 81-82%; HR: 76-88%, 82-83%; SpO2: 72-85%, 82-83%; RR: 34-82%, 77-79%; GCS score: 54-92%, 81-84%; NRS for pain: 0-16%, 24-26%. The increase from 2007-2014 and 2016-2017 was significant as were the differences between 2014 and 2016. We found few defined outliers (0.5%).

CONCLUSIONS

The completeness of registration increased gradually but decreased slightly after implementation of the new version. A high completeness combined with few implausible outliers and concordance indicate correctness of the vital sign registrations.

FUNDING

none.

TRIAL REGISTRATION

Approval for the use of data was given by the medical director of the Emergency Medical Services, the North Denmark Region.

The Danish prehospital emergency healthcare system and research possibilities

The emergency medical healthcare system outside hospital varies greatly across the globe - even within the western world. Within the last ten years, the demand for emergency medical service systems has increased, and the Danish emergency medical service system has undergone major changes.Therefore, we aimed to provide an updated description of the current Danish prehospital medical healthcare system.Since 2007, Denmark has been divided into five regions each responsible for health services, including the prehospital services. Each region may contract their own ambulance service providers. The Danish emergency medical services in general include ambulances, rapid response vehicles, mobile emergency care units and helicopter emergency medical services. All calls to the national emergency number, 1-1-2, are answered by the police, or the Copenhagen fire brigade, and since 2011 forwarded to an Emergency Medical Coordination Centre when the call relates to medical issues. At the Emergency Medical Coordination Centre, healthcare personnel assess the situation guided by the Danish Index for Emergency Care and determine the level of urgency of the situation, while technical personnel dispatch the appropriate medical emergency vehicles. In Denmark, all healthcare services, including emergency medical services are publicly funded and free of charge. In addition to emergency calls, other medical services are available for less urgent health problems around the clock. Prehospital personnel have since 2015 utilized a nationwide electronic prehospital medical record. The use of this prehospital medical record combined with Denmark's extensive registries, linkable by the unique civil registration number, enables new and unique possibilities to do high quality prehospital research, with complete patient follow-up.

Symptom, diagnosis and mortality among respiratory emergency medical service patients

OBJECTIVE

Breathing difficulties and respiratory diseases have been under-reported in Emergency Medical Services research, despite these conditions being prevalent with substantial mortality. Our aim was two-fold; 1) to investigate the diagnostic pattern and mortality among EMS patients to whom an ambulance was dispatched due to difficulty breathing, and 2) to investigate the initial symptoms and mortality for EMS patients diagnosed with respiratory diseases in hospital.

METHODS

Population-based historic cohort study in the North Denmark Region 2012-2015. We included two patient groups; 1) patients calling the emergency number with breathing difficulty as main symptom, and 2) patients diagnosed with respiratory diseases in hospital following an emergency call. Main outcome was estimated 1- and 30-day mortality rates.

RESULTS

There were 3803 patients with the symptom breathing difficulty, nearly half were diagnosed with respiratory diseases 47.3%, followed by circulatory diseases 13.4%, and symptoms and signs 12.0%. The 1-day mortality rate was highest for circulatory diseases, then respiratory diseases and other factors. Over-all 30-day mortality was 13.2%, and the highest rate was for circulatory diseases (17.7%) then respiratory diseases and other factors. A total of 4014 patients were diagnosed with respiratory diseases, 44.8% had the symptom breathing difficulty, 13.4% unclear problems and 11.3%. chest pain/heart disease. 1-day mortality rates were highest for decreased consciousness, then breathing difficulties and unclear problem. Over-all 30-day mortality rates were 12.5%, the highest with symptoms of decreased consciousness (19.1%), then unclear problem and breathing difficulty. There was an overlap of 1797 patients between the two groups.

CONCLUSIONS

The over-all mortality rates alongside the distribution of symptoms and diagnoses, suggest the breathing difficulty patient group is complex and has severe health problems. These findings may be able to raise awareness towards the patient group, and thereby increase focus on diagnostics and treatment to improve the patient outcome.

Diagnosis and mortality of emergency department patients in the North Denmark region

Background

Emergency departments handle a large proportion of acute patients. In 2007, it was recommended centralizing the Danish healthcare system and establishing emergency departments as the main common entrance for emergency patients. Since this reorganization, few studies describing the emergency patient population in this new setting have been carried out and none describing diagnoses and mortality. Hence, we aimed to investigate diagnoses and 1- and 30-day mortality of patients in the emergency departments in the North Denmark Region during 2014–2016.

Methods

Population-based historic cohort study in the North Denmark Region (580,000 inhabitants) of patients with contact to emergency departments during 2014–2016. The study included patients who were referred by general practitioners (daytime and out-of-hours), by emergency medical services or who were self-referred.

Primary diagnoses (ICD-10) were retrieved from the regional Patient Administrative System. For non-specific diagnoses (ICD-10 chapter ‘Symptoms and signs’ and ‘Other factors’), we searched the same hospital stay for a specific diagnosis and used this, if one was given. We performed descriptive analysis reporting distribution and frequency of diagnoses. Moreover, 1- and 30-day mortality rate estimates were performed using the Kaplan-Meier estimator.

Results

We included 290,590 patient contacts corresponding to 166 ED visits per 1000 inhabitants per year. The three most frequent ICD-10 chapters used were ‘Injuries and poisoning’ (38.3% n = 111,274), ‘Symptoms and signs’ (16.1% n = 46,852) and ‘Other factors’ (14.52% n = 42,195). Mortality at day 30 (95% confidence intervals) for these chapters were 0.86% (0.81–0.92), 3.95% (3.78–4.13) and 2.84% (2.69–3.00), respectively.

The highest 30-day mortality were within chapters ‘Neoplasms’ (14.22% (12.07–16.72)), ‘Endocrine diseases’ (8.95% (8.21–9.75)) and ‘Respiratory diseases’ (8.44% (8.02–8.88)).

Conclusions

Patients in contact with the emergency department receive a wide range of diagnoses within all chapters of ICD-10, and one third of the diagnoses given are non-specific. Within the non-specific chapters, we found a 30-day mortality, surpassing several of the more organ specific ICD-10 chapters.

Trial registration

Observational study - no trial registration was performed.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3361-x) contains supplementary material, which is available to authorized users.

Trends in diagnostic patterns and mortality in emergency ambulance service patients in 2007-2014: a population-based cohort study from the North Denmark Region

OBJECTIVE

Demand for ambulances is growing. Nevertheless, knowledge is limited regarding diagnoses and outcomes in patients receiving emergency ambulances. This study aims to examine time trends in diagnoses and mortality among patients transported with emergency ambulance to hospital.

DESIGN

Population-based cohort study with linkage of Danish national registries.

SETTING

The North Denmark Region in 2007-2014.

PARTICIPANTS

Cohort of 148 757 patients transported to hospital by ambulance after calling emergency services.

MAIN OUTCOME MEASURES

The number of emergency ambulance service patients, distribution of their age, sex, hospital diagnoses, comorbidity, and 1-day and 30-day mortality were assessed by calendar year. Poisson regression with robust variance estimation was used to estimate both age-and sex-adjusted relative risk of death and prevalence ratios for Charlson Comorbidity Index (CCI) to allow comparison by year, with 2007 as reference year.

RESULTS

The annual number of emergency ambulance service patients increased from 24.3 in 2007 to 40.2 in 2014 per 1000 inhabitants. The proportions of women increased from 43.1% to 46.4% and of patients aged 60+ years from 39.9% to 48.6%, respectively. The proportion of injuries gradually declined, non-specific diagnoses increased, especially the last year. Proportion of patients with high comorbidity (CCI≥3) increased from 6.4% in 2007 to 9.4% in 2014, corresponding to an age- and sex-adjusted prevalence ratio of 1.27 (95% CI 1.16 to 1.39). The 1-day and 30 day mortality decreased from 2.40% to 1.21% and from 5.01% to 4.36%, respectively, from 2007 to 2014, corresponding to age-adjusted and sex-adjusted relative risk of 0.43 (95% CI 0.37 to 0.50) and 0.72 (95% CI 0.66 to 0.79), respectively.

CONCLUSION

During the 8-year period, the incidence of emergency ambulance service patients, the proportion of women, elderly, and non-specific diagnoses increased. The level of comorbidity increased substantially, whereas the 1-day and 30-day mortality decreased.