https://orcid.org/0000-0001-8966-5858
Abstract
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.
Background
Ambulance non-conveyance is an increasingly investigated topic, particularly regarding adverse event rates, effectiveness at reducing further health service contacts, patient satisfaction, and paramedic decision-making (Citation1–9). Ebben et al completed a systematic review in 2017 which included 67 studies examining the safety of non-conveyance and found highly variable non-conveyance rates for general patient populations, ranging from 3.7 to 93.7% (Citation2). They also reported that within 24–48 h after non-conveyance, 2.5–6.1% of the patients were re-attended by ambulance, and 4.6–19.0% self-presented to the ED (Citation2). However, the term non-conveyance (or similar terms such as non-transport or attend-no-transport) is an umbrella term for a group of heterogenous care pathways (Citation10).
A specific subset of non-conveyed patients includes those who are referred by paramedics to receive follow-up from their general family practitioner (GP) as well as those discharged at scene with self-care advice. Paramedics are increasingly seen by the public as a guiding service to provide advice for the most appropriate place of care. Simultaneously, they hold a professional obligation to “ensure the services you provide are appropriate, necessary and likely to benefit the patient” (Citation11). As ambulance presentations continue to grow disproportionately to population growth (Citation12), it is increasingly important to meaningfully differentiate between the safety profiles of the various on-scene discharge pathways that paramedics utilize. Studies have evaluated patients referred to a GP compared to patients transported to ED, or non-conveyed patients compared to conveyed patients (Citation4, Citation6, Citation13, Citation14). However, to our knowledge there have been no studies comparing the outcomes of adult patients referred to their GP versus those discharged at scene with self-care advice alone.
Effective communication of a follow-up care plan is known to improve patients’ experiences of non-conveyance, and therefore it is plausible that it also decreases ambulance re-attendance or unplanned ED attendance rates (Citation7). Understanding the prevalence and factors associated with GP referrals, together with any associated negative patient outcomes will help to inform evidence-based, clinically appropriate guidelines for paramedics.
This study aims to describe the prevalence, characteristics, and outcomes of patients who were not conveyed to hospital by ambulance and were instead advised to follow up with a GP. We also sought to identify factors associated with ambulance reattendance, ED presentation, and a high acuity outcome within 48 h.
Methods
Study Design
This was a retrospective linked-data cohort study of adult patients attended by Ambulance Victoria paramedics between the 1st of January 2015 and 30th of June 2019, which was the most recent linked-data available at the time of submission. Case selection criteria included adult patients who were either transported to ED, referred to a GP for follow up, or discharged at scene with self-care advice. Patients who resided in a nursing-staffed residential aged care facility, were enrolled in a palliative care program or over the age of 109 years were excluded as this patient cohort have high rates of ‘not for resuscitation’ orders and goals of care that differ significantly from the general adult population. Cases were also excluded if the patient was deceased, declined ambulance conveyance to ED, or was recommended to attend ED via private transport. The research protocol was approved by the Monash University Human Research Ethics Committee (Project ID: 11681).
Setting
Victoria, Australia has a population of approximately 6.5 million people across 227,000 km2 (Citation15). This population is serviced by a single state-based ambulance provider, Ambulance Victoria, which employs approximately 4,500 full-time equivalent operational staff responding to over 600,000 emergency incidents per year (Citation16). Victoria also has more than 7,600 full-time equivalent GPs employed in a range of settings, including private and public practice (Citation17). In the Australian context, the role of a GP is to provide comprehensive person-centered care with a focus on continuity of care for the individual (Citation18). They serve as gatekeepers within the Australian medical rebate system, coordinating and approving referral to specialists medical practitioners where necessary (Citation19). According to the Australian Institute of Health and Welfare, approximately 90% of Victorians will visit a GP each year and 10–20% of those visits will occur after-hours, although approximately a quarter of patients report that they waited longer than acceptable for a GP appointment (Citation20).
To request an ambulance in Victoria, any member of the public can call Triple Zero (000), the national emergency number. Here, non-clinical staff use the Medical Priority Dispatch System to conduct telephone triage. This triage may result in either dispatch of an emergency ambulance or, for calls identified as low-acuity, transfer of the call for secondary triage by an experienced paramedic or nurse (Citation21). Secondary triage may result in the provision of self-care advice or referral of the patient to an alternative health service that can meet their clinical need (Citation22).
For those cases where an ambulance is dispatched, attending paramedics may choose to convey the patient to hospital, refer the patient on to another provider such as their GP, or discharge the patient at scene with self-care advice. In Victoria, there are no minimum standards dictating the components of a referral to GP. As such a patient listed as ‘referred to GP’ may have been exposed to paramedic referral practices ranging from a statement of advice that the patient should follow-up with their GP if they have further concerns, to a more direct handover where the paramedic phones the GP and discusses ongoing patient care (Citation23).
Data Sources
Data was collected from prehospital electronic patient care records and linked with several datasets where presentation occurred within 48 h of index ambulance presentation, as previously described (Citation24). These datasets included ED presentations recorded within the Victorian Emergency Minimum Dataset, hospital admissions recorded within the Victorian Admitted Episodes Dataset, and deaths recorded within the Victorian Death Index.
Definitions
The three outcomes of interest within this paper included ambulance reattendance, ED attendance, and a high acuity outcome, each within 48 h of index ambulance attendance. We defined a high acuity outcome as a patient who:.
presented to ED and received an Australasian Triage Scale of category 1 (Resuscitation) or 2 (Emergency) (Citation25) AND was admitted to a ward: OR
was admitted to an Intensive Care Unit, Coronary Care Unit or Catheter laboratory regardless of triage category: OR
died.
Rurality was described as metropolitan or non-metropolitan according to the Australian Statistical Geography Standard – Remoteness Area (Citation26), and socio-economic status was defined using the Index of Relative Socio-economic Advantage and Disadvantage (IRSAD), and reported in quintiles (Citation27). Comorbidities were calculated using the age-adjusted Charlson Comorbidity Index (ACCI), which is assumed to be zero where paramedics have not recorded any preexisting conditions (Citation28).
Paramedics also record a prehospital diagnosis in their patient care record. For this study, these diagnoses were grouped by bodily system where appropriate, as per Appendix: Classification of paramedic diagnoses by body system. Paramedics were also able to select ‘no problem identified’ or ‘unknown problem’ in the case of an unspecified complaint. Call type was defined as high acuity if the patient received a lights-and-sirens ambulance dispatch, or low acuity if the ambulance was not dispatched lights-and-sirens.
Statistical Analysis
Categorical variables are presented as number and percentage, and continuous variables are presented as median and interquartile range (IQR). Due to the large sample size included in this study, minor differences that lack clinical significance were likely to attain statistical significance. Therefore, univariate, and bivariate statistical analyses were not conducted, and statistical significance testing was reserved for multivariable modeling.
We constructed three multivariable logistic regression models to understand the factors independently associated with patient outcomes. The outcomes of interest were 1) a high acuity outcome, 2) reattendance by ambulance, 3) ED presentation. Variables were considered for inclusion in these models based on clinical relevance and known confounding, as per previous literature and all covariates are listed in the model output (Citation29). The bivariate associations between numerical variables and outcomes of interest were visually plotted. Variables that demonstrated a monotonic relationship with severity of presentation, such as ACCI, patient temperature, oxygen saturation percentage, numerical pain score rating, and socioeconomic status quintile are described as discrete numerical variables. Variables that demonstrated a non-monotonic relationship such as patient heart rate, respiratory rate, and systolic blood pressure were categorized accordingly. The relationships within the models were described using adjusted odds ratio (AOR) and 95% confidence intervals (CI). The performance of the logistic regression models was assessed by calculating the area under a receiver operating characteristic curve. Analyses were performed using STATA version 16 (Citation30).
Results
A total of 2,360,991 prehospital patient care records were retrieved, of which 1,777,950 cases were included as shown in . In total, 54,449 (3.1%) patients were referred to their GP, 160,651 (9.0%) were discharged at scene with self-care advice, and 1,562,850 (87.9%) were transported to hospital.
Figure 1. Flowchart of patients considered for study inclusion.
Baseline Characteristics
The demographic characteristics of included patients are described in . The median age was 60 years (IQR 40–78), and 46.7% were male. Patients referred to their GP were less likely to have preexisting comorbid conditions compared to transported patients.
Table 1. Demographic characteristics of included patients attended to ambulance between 2015 and 2019.
Paramedic Findings
Patients presenting with a paramedic diagnosis of ‘pain’ constituted the highest group of patients referred to a GP (18.7%). In comparison, patients with ‘no problem identified’ constituted the largest group of patients discharged at scene (29.3%) as seen in . There were no conditions where the most common outcome was referral to GP, however sub-analysis of non-transported patients demonstrated that patients who presented with complaints of ‘other infection’ and ‘genitourinary complaints’ were more commonly referred to a GP than discharged at scene without referral. Overall, a high proportion of cases were dispatched lights-and-sirens, including most patients who went on to be referred to a GP.
Table 2. Paramedic findings as recorded on patient care record between 2015 and 2019.
Unadjusted Patient Outcomes
Patient outcomes are presented in . Overall, patients who were referred to a GP or discharged at scene experienced low rates of a high acuity outcome (0.3% and 0.2%, respectively), with death a rare occurrence. Additionally, the rate of reattendance by ambulance within 48 h was similar between patients who were discharged at scene or referred to their GP (6.0% for both), however patients who were transported to ED had lower rates of ambulance reattendance (2.9%). Overall, the proportion of patients who received an ED triage category of 1 or 2 (Resuscitation or Emergency) was 23.6%, and approximately half of the cohort required admission to hospital (48.7%).
Table 3. Patient outcomes within 48 h of ambulance attendance between 2015 and 2019.
Multivariable Analyses
Factors associated with increased adjusted odds of a high acuity outcome occurring within 48 h of ambulance non-conveyance included increasing age and comorbidities, male gender, decreased SPO2%, elevated temperature or respiratory rate, and a paramedic diagnosis that was respiratory or infective in nature, as shown in . When comparing the multivariable regression analyses for the three outcomes of interest, only male gender and elevated temperature were found to be universally predictive amongst the three outcomes of interest. While referral to a GP was linked to increased ED attendance (AOR 1.32; 95%CI 1.24–1.41), it did not correlate with a higher likelihood of a high acuity outcome occurring (AOR 1.29; 95%CI 0.99–1.69) or ambulance reattendance (AOR 1.00; 95%CI 0.95–1.06).
Table 4. Multivariable analyses predicting outcomes within 48 h of ambulance non-conveyance between 2015 and 2019.
Discussion
In our large data linkage study, only 3.1% of patients attended by paramedics were referred to a GP for ongoing follow-up, while 9.0% were discharged at scene with self-care advice alone. Importantly, a high acuity outcome was rare for non-transported patients, occurring in 0.3% of patients referred to a GP and 0.2% of patients discharged at scene. While referral to a GP was independently associated with a 32% increased likelihood of ED attendance compared to those discharged at scene, most predictors of subsequent ambulance attendance or ED presentation, including referral to a GP, did not correlate with increased risk of high acuity outcomes.
While subsequent ED presentation is often used as a proxy for inappropriate ambulance non-conveyance, our research showed significant variation between factors that were associated with a subsequent high acuity outcome and ambulance reattendance or ED presentation. Patients with lower socioeconomic status, initial low acuity ambulance dispatch, and previous mental health diagnoses were more likely to have ambulance reattendance without a corresponding increase in likelihood high acuity outcome occurrence. Similarly, paramedic diagnoses within our study associated with increased likelihood of ED presentation, such as traumatic injuries, and obstetric or gynecological issues, may be appropriate to present to the ED via private vehicle. While referral to a GP increased the likelihood of patients attending the ED compared to patients who were discharged at scene, these patients were not at an increased risk of serious illness. Almost half of the non-conveyed patients who presented to ED were triaged with a semi- or non-urgent attendance, and only 3.4% of the patients referred to a GP were subsequently admitted to hospital within 48 h. Emergency department attendance following ambulance referral to GP therefore may be related to other drivers of ED demand such as GP availability and cost, perceived urgency of the condition, and convenience of integrated radiology available in EDs (Citation31, Citation32). Ambulance re-attendance and/or ED presentation are therefore unlikely to be appropriate proxies for identifying clinically inappropriate ambulance non-conveyance.
Patients with a primary complaint of an infection, including genitourinary symptoms, were the only cohort of non-transported patients more likely to be referred to a GP than discharged at scene, likely reflecting the need for antimicrobial therapy. Given the low overall GP referral rate, there may be an opportunity to educate paramedics around the potential benefits of patient referral to GPs whose role it is to ensure “continuous, comprehensive, patient-centered and high-quality care” (Citation18). Existing evidence suggests that patients who follow-up the with a GP after hospital discharge are less likely to experience an unplanned readmission (Citation33, Citation34). In our study, referral to a GP was associated with an increased likelihood of subsequent ED attendance however we were not able to ascertain if the patients had attended their GP prior to this ED attendance. It is possible that patients with a GP referral may have instead attended the ED in lieu of the GP and so the GP had not yet had an opportunity to provide preventative care. Future research linking ambulance referrals with subsequent GP attendances would provide further insight into this knowledge gap.
In context of local protocols, all paramedics are eligible to refer patients to a GP however previous research indicates there is significant variation in paramedic referral practices. Approximately 10% of patients documented as ‘referred to GP’ reported they were unaware or unable to recall the paramedic referring them to a GP (Citation23). In the pediatric non-conveyed population, increasing paramedic exposure to non-conveyances was associated with increased odds of ED presentation or hospital admission (Citation35). Our dataset did not contain identifiers for individual paramedics and thus it was unable to be determined if similar associations existed in the adult population. Further research exploring how paramedic referral communication and behaviors impact on patient deterioration following non-conveyance are necessary to inform policy and guidelines on paramedic non-conveyance.
Overall, our results suggest that referral from paramedics to a GP in Victoria, Australia is a safe practice with only 0.3% of non-conveyed patients referred to a GP experiencing a high acuity outcome. Despite this, fear of adverse outcomes is a key barrier to decreasing conveyance rates (Citation1, Citation8). In the United Kingdom for example, higher levels of ambulance conveyance is associated with ambulance services where staff described senior management as ‘risk averse’ to non-conveyance (Citation36). Research involving Victoria, Australia has shown that ambulance demand continues to grow disproportionately to population growth, and many patients who are transported to hospital do not receive intervention from paramedics (Citation12). In our study, less than one quarter of patients who were initially conveyed to hospital via ambulance were triaged as category 1 or 2 (Resuscitation or Emergency), suggesting that a large proportion of conveyed patients may not require emergency care. Non-conveyed patients generally describe high levels of satisfaction with their ambulance experience, and report that they initially contacted ambulance for advice, referral, and reassurance (Citation9). Support from ambulance service management endorsing the evidence-based safety profile of GP referrals would likely decrease inappropriate ambulance conveyance and ease ED crowding, whilst better serving the patient’s needs.
Many EMS organizations are now incorporating specialist paramedic roles with an expanded primary healthcare skillset often referred to as a paramedic practitioner, community paramedic, or extended-care paramedic into their workforces to alleviate pressures on EDs and reduce unnecessary conveyances for minor complaints (Citation37). There were no community paramedicine models operating in Victoria, Australia during this study collection period, however these models have been shown to be both effective and financially viable. Improved integration between paramedics and GPs is likely beneficial and cost-effective for patients and the broader healthcare system, whilst noting that the important role that GPs fulfill as care coordinators helps ensure continuous and comprehensive care and cannot be solely provided by a paramedic workforce (Citation18). Further research exploring how integration of paramedic practitioners into the paramedic workforce impacts on paramedic to GP referral patterns will assist in continued workforce planning.
Limitations
Despite a comprehensive patient care record, there are complexities in quantifying patient wellness at the time of paramedic decision to convey, refer or discharge at scene that cannot be accounted for in this dataset. These include the paramedic’s impression of the patient’s ability to self-care, overall and condition-specific health literacy, access to transportation, patient or carer concern and access to a GP. Furthermore, the dataset used for analysis was collected prior to the COVID-19 pandemic. As the pandemic has significantly impacted the healthcare system and health-seeking behaviors (Citation38) caution should be taken when interpreting the results of this study considering the current healthcare context. Future research identifying differences in referral behaviors and outcome pre- and post- the COVID-19 pandemic will further enhance our understanding of ambulance non-conveyance.
The linked dataset utilized for this study linked an ED record to 74% of patients known to have been transported to a public ED (Citation24). Therefore, outcomes in this study may be underreported. It was not clear from the dataset if subsequent ambulance reattendance, ED presentation, hospital admission, or death was related to the initial ambulance attendance or an unrelated secondary event. A 48-h timeframe for follow-up was utilized to minimize the risk of unrelated secondary events compared to a longer 7- or 30- day follow-up period. Our definition of a high acuity outcome required patients to be admitted to hospital or die within 48 h of their EMS attendance. It therefore excluded patients triaged as Category 1 or 2 at ED who were not subsequently admitted to hospital, such as those with an ED diagnosis of non-concerning chest pain or simple intoxication of alcohol. A strength of our study lies in the use of a rich linked dataset to define a meaningful composite high acuity outcome.
Conclusion
Patients attended by paramedics in this EMS system and not conveyed to hospital rarely experience a high acuity outcome within 48 h. Referring a patient to a GP was not associated with a reduced likelihood of experiencing a high acuity outcome or ambulance reattendance within 48 h, however, was associated with increased odds of ED presentation. Paramedics should be aware of factors associated with an increased likelihood of a high acuity outcome occurring such as patient increasing age and comorbidities, male gender, decreased SPO2%, elevated temperature or respiratory rate, and a paramedic diagnosis that was respiratory or infective in nature, as these patients exhibiting these characteristics may benefit from additional safety-netting to prevent and recognize deterioration. Further opportunity exists to refine paramedic-GP referral practices, which may be generalizable to other EMS systems.
Acknowledgments
The authors would like to acknowledge the Victorian Department of Health as the source of VAED and VEMD data for this study, the Victorian Registry of Births, Deaths, and Marriages as the source of Victorian Death Index data and the Centre for Victorian Data Linkage (Victorian Department of Health) for the provision of data linkage.
Disclosure Statement
No potential conflict of interest was reported by the author(s).
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