Utilization of Emergency Medical Services by Culturally and Linguistically Diverse Patients: A Population-Based Retrospective Study.

OBJECTIVES: To compare emergency medical services (EMS) utilization between culturally and linguistically diverse (CALD) and non-CALD patients in Victoria, Australia. METHODS: A retrospective study of EMS attendances and transports in Victoria from January 2015 to June 2019, utilizing linked EMS, hospital emergency and admissions data. The CALD and non-CALD patients who received EMS care and transport to a Victorian public emergency department were included. The incidence of EMS use for CALD and non-CALD patients based on the 2016 Census population and expressed per 100,000 person-years. RESULTS: In 1,261,167 included patients, there were 272,100 (21.6%) CALD and 989,067 (78.4%) non-CALD patients. Before adjustment for age and sex, EMS utilization for CALD patients was 13% lower than non-CALD patients (incidence rate ratio [IRR] 0.87, 95% CI: 0.87-0.87). When stratified by age groups, CALD patients aged under 70 years had significantly lower rates of EMS utilization than non-CALD patients, while CALD patients aged 75 years or older were more likely than non-CALD patients to use EMS (IRR 1.08, 95% CI: 1.07-1.09). The CALD patients were less likely to utilize EMS for trauma/external injury (IRR = 0.67, 95% CI: 0.66-0.68) and mental health/alcohol/drug problems (IRR = 0.39, 95% CI: 0.38-0.40). After adjustment for differences in the age and sex distribution of CALD and non-CALD populations, CALD patients were 51% less likely to utilize EMS than non-CALD patients (IRR 0.49, 95% CI: 0.42-0.56). CONCLUSIONS: The CALD patients used EMS less frequently than non-CALD patients with significant variation observed across age groups, countries of birth, and clinical presentation. Further research is needed to understand the factors that may be contributing to these disparities.

Characteristics and Outcomes of Patients Referred to a General Practitioner by Victorian Paramedics.

OBJECTIVE: Many patients who are attended by paramedics do not require conveyance to an emergency department (ED). Our study focuses on comparing the characteristics and outcomes of patients who were advised to follow up with a general practitioner (GP) by an attending paramedic with those of patients who were discharged at scene or transported to hospital. METHODS: This was a retrospective data linkage cohort study of ambulance, ED, hospital admission, and death records for all adults attended by paramedics in Victoria, Australia between the 1st of January 2015 and 30th of June 2019. Patients were excluded if they presented in cardiac arrest, resided in a residential aged care facility, or were receiving palliative care services. Outcomes of interest included reattendance by ambulance, ED presentation; and, a high acuity outcome which we defined as a patient who (1) presented to ED and received an Australasian Triage Scale of category 1 (Resuscitation) or 2 (Emergency) AND was admitted to a ward OR (2) was admitted to an Intensive Care Unit, Coronary Care Unit or Catheter laboratory (regardless of triage category) OR (3) died. Outcomes of interest were considered within 48-h of initial EMS attendance. RESULTS: A total of 1,777,950 cases were included in the study of which 3.1% were referred to a GP, 9.0% were discharged at scene without a follow-up recommendation, and 87.9% were transported to hospital. Patients referred to a GP were more likely than those discharged at scene to subsequently present to an ED within 48 h of their attendance (5.3% vs 3.8%). However, GP referral was not associated with any change to high acuity outcome (0.3% vs 0.2%) or ambulance reattendance (6.0% vs 6.0%) compared to discharge at scene. The only factors that were associated with ambulance reattendance, ED presentation, and a high acuity outcome were male gender and elevated temperature. CONCLUSIONS: Despite increasing low and medium-acuity casework in this EMS system, paramedic referral to a GP is not common practice. Referring a patient to a GP did not reduce the likelihood of patients experiencing a high acuity outcome or recalling an ambulance within 48 h, suggesting opportunity exists to refine paramedic to GP referral practices.

Outcomes of adult patients discharged at scene by emergency medical services.

BACKGROUND: The outcomes of patients who call an ambulance but are discharged at scene reflect the safety and quality of emergency medical service (EMS) care. While previous studies have examined the outcomes of patients discharged at scene, none have specifically focused on paramedic-initiated discharge. This study aims to describe the outcomes of adult patients discharged at scene by paramedics and identify factors associated with 72-hour outcomes. METHODS: This was a retrospective data linkage study on consecutive adult EMS patients discharged at scene by paramedics in Victoria, Australia, between 1 January 2015 and 30 June 2019. Multivariable logistic regression was used to investigate factors associated with EMS recontact, ED presentation, hospital admission and serious adverse events (death, cardiac arrest, category 1 triage or intensive care unit admission) within 72 hours of the initial emergency call. RESULTS: There were 375 758 cases of adults discharged at scene following EMS attendance, of which 222 571 (59.2%) were paramedic-initiated decisions. Of these, 6.8% recontacted EMS, 5.0% presented to ED, 2.4% were admitted to hospital and 0.3% had a serious adverse event in the following 72 hours. The odds of EMS recontact were increased in cases related to mental health (adjusted OR (AOR) 1.41 (95% CI 1.33 to 1.49)), among low-income government concession holders (AOR 1.61 (95% CI 1.55 to 1.67)) and in areas of low socioeconomic advantage (AOR 1.19 (95% CI 1.13 to 1.25)). The odds of hospital admission were increased in cases related to infection (AOR 3.14 (95% CI 2.80 to 3.52)) and pain (AOR 1.93 (95% CI 1.75 to 2.14)). The strongest driver of serious adverse events was an abnormal vital sign (AOR 4.81 (95% CI 3.87 to 5.98)). CONCLUSION: The occurrence of hospital admission and adverse events is rare in those discharged at scene, suggesting generally safe decision-making. However, increased attention to elderly, multimorbid patients or patients with infection and pain is recommended, as is further research examining the use of tools to aid paramedic recognition of potential for deterioration.

Outcomes of paediatric patients who are not transported to hospital by Emergency Medical Services: a data linkage study.

BACKGROUND: Data on the safety of non-transport decisions for paediatric patients attended by Emergency Medical Services (EMS) are lacking. We describe the characteristics and outcomes of paediatric non-transported patients in Victoria, Australia. METHODS: A retrospective data linkage study of consecutive paediatric (aged <18 years) non-transported patients between January 2015 and June 2019. Patients were linked to ED, hospital admission and death records. Multivariable logistic regression analyses were used to determine factors associated with EMS recontact, ED presentation, hospital admission and an adverse event (death/cardiac arrest, intensive care unit admission or highest ED triage category) within 48 hours of the initial emergency call. RESULTS: In total, 62 975 non-transported patients were included. The mean age was 7.1 (SD 6.0) years and 48.9% were male. Overall, 2.2% recontacted the EMS within 48 hours, 13.7% self-presented to a public ED, 2.4% were admitted to hospital and 0.1% had an adverse event, including two deaths. Among patients with paramedic-initiated non-transport (excluding transport refusals and transport via other means), 5.6% presented to a public ED, 1.1% were admitted to hospital and 0.05% had an adverse event. In the overall population, an abnormal vital sign on initial assessment increased the odds of hospital admission and an adverse event. Among paramedic-initiated non-transports, cases occurring in the early hours of the morning (04:00-08:00 hours) were associated with increased odds of subsequent hospital admission, while the odds of ED presentation and hospital admission also increased with increasing prior exposure to non-transported cases. CONCLUSION: Adverse events were rare among paramedic-initiated non-transport cases. Vital sign derangements and attendance by paramedics with higher prior exposure to non-transports were associated with poorer outcomes and may be used to improve safety.

Healthcare cost burden of acute chest pain presentations.

BACKGROUND: This study aimed to estimate the direct healthcare cost burden of acute chest pain attendances presenting to ambulance in Victoria, Australia, and to identify key cost drivers especially among low-risk patients. METHODS: State-wide population-based cohort study of consecutive adult patients attended by ambulance for acute chest pain with individual linkage to emergency and hospital admission data in Victoria, Australia (1 January 2015-30 June 2019). Direct healthcare costs, adjusted for inflation to 2020-2021 ($A), were estimated for each component of care using a casemix funding method. RESULTS: From 241 627 ambulance attendances for chest pain during the study period, mean chest pain episode cost was $6284, and total annual costs were estimated at $337.4 million ($68 per capita per annum). Total annual costs increased across the period ($310.5 million in 2015 vs $384.5 million in 2019), while mean episode costs remained stable. Cardiovascular conditions (25% of presentations) were the most expensive (mean $11 523, total annual $148.7 million), while a non-specific pain diagnosis (49% of presentations) was the least expensive (mean $3836, total annual $93.4 million). Patients classified as being at low risk of myocardial infarction, mortality or hospital admission (Early Chest pain Admission, Myocardial infarction, and Mortality (ECAMM) score) represented 31%-57% of the cohort, with total annual costs estimated at $60.6 million-$135.4 million, depending on the score cut-off used. CONCLUSIONS: Total annual costs for acute chest pain presentations are increasing, and a significant proportion of the cost burden relates to low-risk patients and non-specific pain. These data highlight the need to improve the cost-efficiency of chest pain care pathways.

Variation in Health Care Processes, Quality and Outcomes According to Day and Time of Chest Pain Presentation via Ambulance.

BACKGROUND: Previous studies examining temporal variations in cardiovascular care have largely been limited to assessing weekend and after-hours effects. We aimed to determine whether more complex temporal variation patterns might exist in chest pain care. METHODS: This was a population-based study of consecutive adult patients attended by emergency medical services (EMS) for non-traumatic chest pain without ST elevation in Victoria, Australia between 1 January 2015 and 30 June 2019. Multivariable models were used to assess whether time of day and week stratified into 168 hourly time periods was associated with care processes and outcomes. RESULTS: There were 196,365 EMS chest pain attendances; mean age 62.4 years (standard deviation [SD] 18.3) and 51% females. Presentations demonstrated a diurnal pattern, a Monday-Sunday gradient (Monday peak) and a reverse weekend effect (lower rates on weekends). Five temporal patterns were observed for care quality and process measures, including a diurnal pattern (longer emergency department [ED] length of stay), an after-hours pattern (lower angiography or transfer for myocardial infarction, pre-hospital aspirin administration), a weekend effect (shorter ED clinician review, shorter EMS off-load time), an afternoon/evening peak period pattern (longer ED clinician review, longer EMS off-load time) and a Monday-Sunday gradient (ED clinician review, EMS offload time). Risk of 30-day mortality was associated with weekend presentation (Odds ratio [OR] 1.15, p=0.001) and morning presentation (OR 1.17, p<0.001) while risk of 30-day EMS reattendance was associated with peak period (OR 1.16, p<0.001) and weekend presentation (OR 1.07, p<0.001). CONCLUSIONS: Chest pain care demonstrates complex temporal variation beyond the already established weekend and after-hours effect. Such relationships should be considered during resource allocation and quality improvement programs to improve care across all days and times of the week.

The influence of ambulance offload time on 30-day risks of death and re-presentation for patients with chest pain.

OBJECTIVE: To assess whether ambulance offload time influences the risks of death or ambulance re-attendance within 30 days of initial emergency department (ED) presentations by adults with non-traumatic chest pain. DESIGN, SETTING: Population-based observational cohort study of consecutive presentations by adults with non-traumatic chest pain transported by ambulance to Victorian EDs, 1 January 2015 - 30 June 2019. PARTICIPANTS: Adults (18 years or older) with non-traumatic chest pain, excluding patients with ST elevation myocardial infarction (pre-hospital electrocardiography) and those who were transferred between hospitals or not transported to hospital (eg, cardiac arrest or death prior to transport). MAIN OUTCOME MEASURES: Primary outcome: 30-day all-cause mortality (Victorian Death Index data). SECONDARY OUTCOME: Transport by ambulance with chest pain to ED within 30 days of initial ED presentation. RESULTS: We included 213 544 people with chest pain transported by ambulance to EDs (mean age, 62 [SD, 18] years; 109 027 women [51%]). The median offload time increased from 21 (IQR, 15-30) minutes in 2015 to 24 (IQR, 17-37) minutes during the first half of 2019. Three offload time tertiles were defined to include approximately equal patient numbers: tertile 1 (0-17 minutes), tertile 2 (18-28 minutes), and tertile 3 (more than 28 minutes). In multivariable models, 30-day risk of death was greater for patients in tertile 3 than those in tertile 1 (adjusted rates, 1.57% v 1.29%; adjusted risk difference, 0.28 [95% CI, 0.16-0.42] percentage points), as was that of a second ambulance attendance with chest pain (adjusted rates, 9.03% v 8.15%; adjusted risk difference, 0.87 [95% CI, 0.57-1.18] percentage points). CONCLUSIONS: Longer ambulance offload times are associated with greater 30-day risks of death and ambulance re-attendance for people presenting to EDs with chest pain. Improving the speed of ambulance-to-ED transfers is urgently required.

Descriptive Analysis Of Mental Health-Related Presentations To Emergency Medical Services.

OBJECTIVE: In many developed countries, a lack of community-based mental health services is driving increased utilization of emergency medical services (EMS). In this descriptive study, we sought to describe the demographic and clinical characteristics of mental health-related EMS presentations in Victoria, Australia. METHODS: A retrospective observational study of EMS presentations occurring between January and December 2015. Computer Aided Dispatch and electronic patient care record data were extracted from an electronic data warehouse. Characteristics of EMS-attended mental health presentations were described and compared to other EMS-attended patients using descriptive statistics. RESULTS: Of the total 504,676 EMS attendances, 48,041 (9.5%) were mental health presentations. In addition, 4,708 (6.6%) cases managed by a paramedic or nurse via the EMS secondary telephone triage service also involved mental health complaints. EMS-attended mental health patients were younger and more often female compared to other patients attended by EMS. Most mental health patients were transported to hospital (74.4%); however, paramedics provided treatment to significantly fewer mental health patients compared to other EMS-attended patients (12.4% vs. 50.3%, p < 0.001%). The majority of mental health patients (76.8%) had a documented mental health history. Social or emotional issues were the most common presentation in mental health patients aged ≤15 years (19.1%); whereas, for patients aged ≥65 years, anxiety was the most common clinical presentation (41.2%). For patients undergoing secondary triage, 52.5% were frequent callers or anxiety presentations. A total of 27.7% of triaged patients were referred to an alternative service, while 24.6% were managed under an existing care plan. CONCLUSION: Mental health-related cases represent one in ten EMS attendances in Victoria. A large proportion of mental health presentations receive little intervention by EMS, and could benefit from community-based services provided by mental health clinicians.

Prehospital Predictors of Traumatic Spinal Cord Injury in Victoria, Australia.

OBJECTIVES: To identify the predictors of traumatic spinal cord injury (TSCI) and describe the differences between confirmed and potential TSCI cases in the prehospital setting. METHODS: A retrospective cohort study including all adult patients over a six-year period (2007-12) with potential TSCI who were attended and transported by Ambulance Victoria (AV). We extracted potential TSCI cases from the AV data warehouse and linked with the Victorian State Trauma Registry to compare with final hospital diagnosis. RESULTS: We included a total of 106,059 patients with potential TSCI in the study, with 257 having a spinal cord injury confirmed at hospital (0.2%). The median [First and third Quartiles] age of confirmed TSCI cases was 49 [32-69] years, with males comprising 84.1%. Confirmed TSCI were mainly due to falls (44.8%) and traffic incidents (40.5%). AV spinal care guidelines had a sensitivity of 100% to detect confirmed TSCI. There were several factors associated with a diagnosis of TSCI. These were meeting AV Potential Major Trauma criteria, male gender, presence of neurological deficit, presence of an altered state of consciousness, high falls (> 3 meters), diving, or motorcycle or bicycle collisions. CONCLUSION: This study identified several predictors of TSCI including meeting AV Potential Major Trauma criteria, male gender, presence of neurological deficit, presence of an altered state of consciousness, high falls (> 3 meters), diving, or motorcycle or bicycle collisions. Most of these predictors are included in NEXUS and/or CCR criteria, however, Potential Major Trauma criteria have not previously been linked to the presence of TSCI. Therefore, Emergency Medical Systems are encouraged to integrate similar Potential Major Trauma criteria into their guidelines and protocols to further improve the provider's accuracy in identifying TSCI and to be more selective in their spinal immobilization, thereby reducing unwarranted adverse effects of this practice.

Refining ambulance clinical response models: The impact on ambulance response and emergency department presentations.

OBJECTIVE: The ambulance service in Victoria, Australia implemented a revised clinical response model (CRM) in 2016 which was designed to increase the diversion of low-acuity Triple Zero (000) calls to secondary telephone triage and reduce emergency ambulance dispatches. The present study evaluates the influence of the revised CRM on emergency ambulance response times and ED presentations. METHODS: A retrospective study of emergency calls for ambulance between 1 January 2015 and 31 December 2018. Ambulance data were linked with ED presentations occurring up to 48 h after contact. Interrupted time series analyses were used to evaluate the impact of the revised CRM. RESULTS: A total of 2 365 529 calls were included. The proportion allocated a Code 1 (time-critical, lights/sirens) dispatch decreased from 56.6 to 41.0% after implementation of the revised CRM. The proportion of calls not receiving an emergency ambulance increased from 10.4 to 19.6%. Interrupted time series analyses demonstrated an improvement in Code 1 cases attended within 15 min (Key Performance Indicator). However, for patients with out-of-hospital cardiac arrest or requiring lights and sirens transport to hospital, there was no improvement in response time performance. By the end of the study period, there was also no difference in the proportion of callers presenting to ED when compared with the estimated proportion assuming the revised CRM had not been implemented. CONCLUSION: The revised CRM was associated with improved Code 1 response time performance. However, there was no improvement in response times for high acuity patients, and no change in the proportion of callers presenting to ED.

Association of socioeconomic status in the incidence, quality-of-care metrics, and outcomes for patients with cardiogenic shock in a pre-hospital setting.

AIMS: The relationship between lower socioeconomic status (SES) and poor cardiovascular outcomes is well described; however, there exists a paucity of data exploring this association in cardiogenic shock (CS). This study aimed to investigate whether any disparities exist between SES and the incidence, quality of care or outcomes of CS patients attended by emergency medical services (EMS). METHODS AND RESULTS: This population-based cohort study included consecutive patients transported by EMS with CS between 1 January 2015 and 30 June 2019 in Victoria, Australia. Data were collected from individually linked ambulance, hospital, and mortality datasets. Patients were stratified into SES quintiles using national census data produced by the Australian Bureau of Statistics.A total of 2628 patients were attended by EMS for CS. The age-standardized incidence of CS amongst all patients was 11.8 [95% confidence interval (95% CI), 11.4-12.3] per 100 000 person-years, with a stepwise increase from the highest to lowest SES quintile (lowest quintile 17.0 vs. highest quintile 9.7 per 100 000 person-years, P-trend < 0.001). Patients in lower SES quintiles were less likely to attend metropolitan hospitals and more likely to be received by inner regional and remote centres without revascularization capabilities. A greater proportion of the lower SES groups presented with CS due to non-ST elevation myocardial infarction (NSTEMI) or unstable angina pectoris (UAP), and overall were less likely to undergo coronary angiography. Multivariable analysis demonstrated an increased 30-day all-cause mortality rate in the lowest three SES quintiles when compared with the highest quintile. CONCLUSION: This population-based study demonstrated discrepancies between SES status in the incidence, care metrics, and mortality rates of patients presenting to EMS with CS. These findings outline the challenges in equitable healthcare delivery within this cohort.

Impact of socioeconomic status on presentation, care quality and outcomes of patients attended by emergency medical services for dyspnoea: a population-based cohort study.

BACKGROUND: Low socioeconomic status (SES) has been linked to poor outcomes in many conditions. It is unknown whether these disparities extend to individuals presenting with dyspnoea. We aimed to evaluate the relationship between SES and incidence, care quality and outcomes among patients attended by emergency medical services (EMS) for dyspnoea. METHODS: This population-based cohort study included consecutive patients attended by EMS for dyspnoea between 1 January 2015 and 30 June 2019 in Victoria, Australia. Data were obtained from individually linked ambulance, hospital and mortality datasets. Patients were stratified into SES quintiles using a composite census-derived index. RESULTS: A total of 262 412 patients were included. There was a stepwise increase in the age-adjusted incidence of EMS attendance for dyspnoea with increasing socioeconomic disadvantage (lowest SES quintile 2269 versus highest quintile 889 per 100 000 person years, ptrend<0.001). Patients of lower SES were younger and more comorbid, more likely to be from regional Victoria or of Aboriginal or Torres Strait Islander heritage and had higher rates of respiratory distress. Despite this, lower SES groups were less frequently assigned a high acuity EMS transport or emergency department (ED) triage category and less frequently transported to tertiary centres or hospitals with intensive care unit facilities. In multivariable models, lower SES was independently associated with lower acuity EMS and ED triage, ED length of stay>4 hours and increased 30-day EMS reattendance and mortality. CONCLUSION: Lower SES was associated with a higher incidence of EMS attendances for dyspnoea and disparities in several metrics of care and clinical outcomes.

Prehospital factors predicting mortality in patients with shock: state-wide linkage study.

BACKGROUND: Patients with shock treated by emergency medical services (EMS) have high morbidity and mortality. Knowledge of prehospital factors predicting outcomes in patients with shock remains limited. We aimed to describe the prehospital predictors of mortality in patients with non-traumatic shock transported to hospital by EMS. METHOD: This is a retrospective cohort study of consecutive ambulance attendances for non-traumatic shock in Victoria, Australia (January 2015-June 2019) linked with government-held administrative data (emergency, admissions and mortality records). Predictors of 30-day mortality were assessed using Cox proportional regressions. The primary outcome was 30-day all-cause mortality. RESULTS: Overall, 21 334 patients with non-traumatic shock (median age 69 years, 54.8% female) were successfully linked with state administrative records. Among this cohort, 9 149 (43%) patients died within 30-days. Compared with survivors, non-survivors had a longer median on-scene time: 60 (35-98) versus 30 (19-50), p <0.001. Non-survivors were more likely to be older (median age in years: 74 (61-84) vs 65 (47-78), p<0.001), had prehospital cardiac arrest requiring cardiopulmonary resuscitation (adjusted HR (aHR)=6.26, 95% CI 5.87, 6.69) and had prehospital intubation (aHR=1.07, CI 1.00, 1.14). Reduced 30-day mortality was associated with administration of epinephrine (aHR=0.66, CI 0.62, 0.71) and systolic blood pressures above 80 mm Hg in the prehospital setting. CONCLUSION: The 30-day mortality from non-traumatic shock is high at 43%. Independent predictors of mortality included age, prehospital cardiac arrest and endotracheal intubation. Interventions that target reversible causes of short-term mortality in patients with non-traumatic shock are a high priority.

Healthcare and economic cost burden of emergency medical services treated non-traumatic shock using a population-based cohort in Victoria, Australia.

OBJECTIVES: We aimed to assess the healthcare costs and impact on the economy at large arising from emergency medical services (EMS) treated non-traumatic shock. DESIGN: We conducted a population-based cohort study, where EMS-treated patients were individually linked to hospital-wide and state-wide administrative datasets. Direct healthcare costs (Australian dollars, AUD) were estimated for each element of care using a casemix funding method. The impact on productivity was assessed using a Markov state-transition model with a 3-year horizon. SETTING: Patients older than 18 years of age with shock not related to trauma who received care by EMS (1 January 2015-30 June 2019) in Victoria, Australia were included in the analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome assessed was the total healthcare expenditure. Secondary outcomes included healthcare expenditure stratified by shock aetiology, years of life lived (YLL), productivity-adjusted life-years (PALYs) and productivity losses. RESULTS: A total of 21 334 patients (mean age 65.9 (±19.1) years, and 9641 (45.2%) females were treated by EMS with non-traumatic shock with an average healthcare-related cost of $A11 031 per episode of care and total cost of $A280 million. Annual costs remained stable throughout the study period, but average costs per episode of care increased (Ptrend=0.05). Among patients who survived to hospital, the average cost per episode of care was stratified by aetiology with cardiogenic shock costing $A24 382, $A21 254 for septic shock, $A19 915 for hypovolaemic shock and $A28 057 for obstructive shock. Modelling demonstrated that over a 3-year horizon the cohort lost 24 355 YLLs and 5059 PALYs. Lost human capital due to premature mortality led to productivity-related losses of $A374 million. When extrapolated to the entire Australian population, productivity losses approached $A1.5 billion ($A326 million annually). CONCLUSION: The direct healthcare costs and indirect loss of productivity among patients with non-traumatic shock are high. Targeted public health measures that seek to reduce the incidence of shock and improve systems of care are needed to reduce the financial burden of this syndrome.

The development of a data-matching algorithm to define the 'case patient'.

OBJECTIVES: To describe a model that matches electronic patient care records within a given case to one or more patients within that case. METHOD: his retrospective study included data from all metropolitan Ambulance Victoria electronic patient care records (n=445576) for the time period 1 January 2009-31 May 2010. Data were captured via VACIS (Ambulance Victoria, Melbourne, Vic., Australia), an in-field electronic data capture system linked to an integrated data warehouse database. The case patient algorithm included 'Jaro-Winkler', 'Soundex' and 'weight matching' conditions. RESULTS: he case patient matching algorithm has a sensitivity of 99.98%, a specificity of 99.91% and an overall accuracy of 99.98%. CONCLUSIONS: The case patient algorithm provides Ambulance Victoria with a sophisticated, efficient and highly accurate method of matching patient records within a given case. This method has applicability to other emergency services where unique identifiers are case based rather than patient based.

The burden and prognostic significance of suspected sepsis in the prehospital setting: A state-wide population-based cohort study.

OBJECTIVE: Despite high in-hospital mortality, the epidemiology of prehospital suspected sepsis presentations is not well described. This retrospective cohort study aimed to quantify the burden of such presentations, and to determine whether such a diagnosis was independently associated with longer-term mortality. METHODS: Retrospective, observational population-based cohort study examining all adult prehospital presentations in Victoria, between January 2015 and June 2019, who required subsequent in-hospital assessment. Linked data were extracted from clinical and administrative datasets. Demographics, illness severity, prehospital treatment and mortality were compared between prehospital suspected sepsis and non-sepsis patients. Multivariable logistic regression was used to determine the adjusted association between prehospital assessment (suspected sepsis vs non-sepsis) and 6-month mortality. RESULTS: A total of 1 218 047 patients were included. The age-adjusted incidence rate of prehospital suspected sepsis was 65 cases per 100 000 person-years. Those with prehospital suspected sepsis were older (74 vs 62 years), more frequently male (55% vs 47%), with greater physiological derangement. Intravenous cannulas were more often inserted prehospital (60% vs 29%). Crude in-hospital mortality was 6.5-fold higher in the prehospital suspected sepsis group (11.8% vs 1.8%), and by 6 months, 22.6% had died. After adjustment for demographics, illness severity, comorbidity, treatment and hospital location, a diagnosis of prehospital suspected sepsis was associated with a 35% higher likelihood of 6-month mortality (OR 1.35, 95% CI 1.29-1.41). CONCLUSIONS: The burden of prehospital suspected sepsis in the Australian setting is significant, with paramedics identifying patients at high-risk of poor longer-term outcomes. This implies the need to consider improved care pathways for this highly vulnerable group.

Epidemiology, outcomes and predictors of mortality in patients transported by ambulance for dyspnoea: A population-based cohort study.

OBJECTIVES: There are currently limited data to inform the management of patients transported by emergency medical services (EMS) with dyspnoea. We aimed to describe the incidence, aetiology and outcomes of patients transported by EMS for dyspnoea using a large population-based sample and to identify factors associated with 30-day mortality. METHODS: Consecutive EMS attendances for dyspnoea in Victoria, Australia from January 2015 to June 2019 were included. Data were individually linked to hospital and mortality records to determine incidence, diagnoses, and outcomes. Factors associated with 30-day mortality were assessed using multivariable logistic regression. RESULTS: During the study period, there were 2 505 324 cases attended by EMS, of whom 346 228 (14%) met inclusion criteria for dyspnoea. The incidence of EMS attendances for dyspnoea was 1566 per 100 000 person-years, and was higher in females, older patients and socially disadvantaged areas. Of the 271 204 successfully linked cases (median age 76 years; 51% women), 79% required hospital admission with a 30-day mortality of 9%. The most common final diagnoses (and 30-day mortality rates) were lower respiratory tract infection (13%, mortality 11%), chronic obstructive pulmonary disease (13%, mortality 6.4%), heart failure (9.1%, mortality 9.8%), arrhythmias (3.9%, mortality 4.4%), acute coronary syndromes (3.9%, mortality 9.5%) and asthma (3.2%, mortality 0.5%). Predictors of mortality included older age, male sex, pre-existing chronic kidney disease, heart failure or cancer, abnormal respiratory status or vital signs and pre-hospital intubation. CONCLUSION: Dyspnoea is a common presentation with a broad range of causes and is associated with high rates of hospitalisation and death.

Age as a predictor of clinical outcomes and determinant of therapeutic measures for emergency medical services treated cardiogenic shock.

BACKGROUND: The impact of age on outcomes in cardiogenic shock (CS) is poorly described in the pre-hospital setting. We assessed the impact of age on outcomes of patients treated by emergency medical services (EMS). METHODS: This population-based cohort study included consecutive adult patients with CS transported to hospital by EMS. Successfully linked patients were stratified into tertiles by age (18-63, 64-77, and > 77 years). Predictors of 30-day mortality were assessed through regression analyses. The primary outcome was 30-day all-cause mortality. RESULTS: A total of 3523 patients with CS were successfully linked to state health records. The average age was 68 ± 16 years and 1398 (40%) were female. Older patients were more likely to have comorbidities including pre-existing coronary artery disease, hypertension, dyslipidemia, diabetes mellitus, and cerebrovascular disease. The incidence of CS was significantly greater with increasing age (incidence rate per 100,000 person years 6.47 [95% CI: 6.1-6.8] in age 18-63 years, 34.34 [32.4-36.4] in age 64-77 years, 74.87 [70.6-79.3] in age > 77 years, P < 0.001). There was a step-wise increase in the rate of 30-day mortality with increasing age tertile. After adjustment, compared to the lowest age tertile, patients aged > 77 years had increased risk of 30-day mortality (adjusted hazard ratio = 2.26 [95% CI: 1.96-2.60]). Older patients were less likely to receive inpatient coronary angiography. CONCLUSION: Older patients with EMS-treated CS have significantly higher rates of short-term mortality. The reduced rates of invasive interventions in older patients underscore the need for further development of systems of care to improve outcomes for this patient group.

Chest pain epidemiology and care quality for Aboriginal and Torres Strait Islander peoples in Victoria, Australia: a population-based cohort study from 2015 to 2019.

Background: This study examined chest pain epidemiology and care quality for Aboriginal and Torres Strait Islander ('Indigenous') patients presenting to hospital via emergency medical services (EMS) with chest pain. Methods: State-wide population-based cohort study of consecutive patients attended by ambulance for acute chest pain with individual linkage to emergency, hospital admission and mortality data in the state of Victoria, Australia from January 2015 to June 2019. Multivariable models were used to assess for differences in pre-hospital and hospital adherence to care quality, process measures and clinical outcomes. Findings: From 204,969 EMS attendances for chest pain, 3890 attendances (1.9%) identified as Aboriginal or Torres Strait Islander. Age-standardized incidence rates were higher overall for Indigenous people (3128 vs. 1147 per 100,000 person-years, incidence rate ratio 2.73, 95% CI 2.72-2.74), this difference being particularly striking for younger patients, women, and those residing in outer regional areas. In multivariable models, adherence to care quality and process measures was lower for attendances involving Indigenous people. In the pre-hospital setting, Indigenous people were less likely to be provided intravenous access or analgesia. In the hospital setting, Indigenous people were less likely to be seen by emergency clinicians within target time and less likely to transferred following myocardial infarction to a revascularization capable centre. Interpretation: Incidence of acute chest pain presentations is high among Indigenous people in Victoria, Australia. Opportunities to improve the quality of care for Indigenous Australians presenting with acute chest pain are identified. Funding: National Health and Medical Research Council, National Heart Foundation.

Risk-standardized mortality metric to monitor hospital performance for chest pain presentations.

AIMS: Risk-standardized mortality rates (RSMR) have been used to monitor hospital performance in procedural and disease-based registries, but limitations include the potential to promote risk-averse clinician decisions and a lack of assessment of the whole patient journey. We aimed to determine whether it is feasible to use RSMR at the symptom-level to monitor hospital performance using routinely collected, linked, clinical and administrative data of chest pain presentations. METHODS AND RESULTS: We included 192 978 consecutive adult patients (mean age 62 years; 51% female) with acute chest pain without ST-elevation brought via emergency medical services (EMS) to 53 emergency departments in Victoria, Australia (1/1/2015-30/6/2019). From 32 candidate variables, a risk-adjusted logistic regression model for 30-day mortality (C-statistic 0.899) was developed, with excellent calibration in the full cohort and with optimism-adjusted bootstrap internal validation. Annual 30-day RSMR was calculated by dividing each hospital's observed mortality by the expected mortality rate and multiplying it by the annual mean 30-day mortality rate. Hospital performance according to annual 30-day RSMR was lower for outer regional or remote locations and at hospitals without revascularisation capabilities. Hospital rates of angiography or transfer for patients diagnosed with non-ST elevation myocardial infarction (NSTEMI) correlated with annual 30-day RSMR, but no correlations were observed with other existing key performance indicators. CONCLUSION: Annual hospital 30-day RSMR can be feasibly calculated at the symptom-level using routinely collected, linked clinical, and administrative data. This outcome-based metric appears to provide additional information for monitoring hospital performance in comparison with existing process of care key performance measures.