Background

In Sweden with about 10 million inhabitants, there are about one million primary ambulance missions every year. Among them, around 10% are assessed by Emergency Medical Service (EMS) clinicians with the primary symptom of dyspnoea. The risk of death among these patients has been reported to be remarkably high, at 11,1% and 13,2%. The aim was to develop a Machine Learning (ML) model to provide support in assessing patients in pre-hospital settings and to compare them with established triage tools.

Methods

This was a retrospective observational study including 6,354 patients who called the Swedish emergency telephone number (112) between January and December 2017. Patients presenting with the main symptom of dyspnoea were included which were recruited from two EMS organisations in Göteborg and Södra Älvsborg. Serious Adverse Event (SAE) was used as outcome, defined as any of the following:1) death within 30 days after call for an ambulance, 2) a final diagnosis defined as time-sensitive, 3) admitted to intensive care unit, or 4) readmission within 72 h and admitted to hospital receiving a final time-sensitive diagnosis. Logistic regression, LASSO logistic regression and gradient boosting were compared to the Rapid Emergency Triage and Treatment System for Adults (RETTS-A) and National Early Warning Score2 (NEWS2) with respect to discrimination and calibration of predictions. Eighty percent (80%) of the data was used for model development and 20% for model validation.

Results

All ML models showed better performance than RETTS-A and NEWS2 with respect to all evaluated performance metrics. The gradient boosting algorithm had the overall best performance, with excellent calibration of the predictions, and consistently showed higher sensitivity to detect SAE than the other methods. The ROC AUC on test data increased from 0.73 (95% CI 0.70–0.76) with RETTS-A to 0.81 (95% CI 0.78–0.84) using gradient boosting.

Conclusions

Among 6,354 ambulance missions caused by patients suffering from dyspnoea, an ML method using gradient boosting demonstrated excellent performance for predicting SAE, with substantial improvement over the more established methods RETTS-A and NEWS2.

1 miljon ambulansuppdrag utförs årligen i Sverige, och behovet av nationell kvalitetssäkring är stort.

Ambureg samlar in data från alla 21 regioner som belyser vården på larmcentralen och i ambulanssjukvården.

Belastningen på ambulanssjukvården har skapat ett behov av hänvisning till egenvård, primärvård och mobila team, vilket ökar kraven på förmågan att bedöma redan på plats.

Snabbspår med direktinläggningar för snabb utredning och behandling är en annan process som ställer ökade krav på ambulanssjukvården.

Morgondagens kvalitetssäkring kommer att omfatta den akuta prehospitala bedömningen och följsamheten till gällande riktlinjer med målet att optimera patientsäkerheten.

Background

The emergency medical service (EMS) addresses all chief complaints across all ages in various contexts. Children in EMS present a particular challenge due to their unique anatomical and physical properties, which require specific training that EMS clinicians often report lacking. This combination exposes children to incidents threatening patient safety. The most common method to highlight incidents is the incident reporting system. Studies have shown underreporting of such incidents, highlighting the need for multiple methods to measure and enhance patient safety in EMS for children. Thus, the aim of this study was to modify and adapt the current Ambulance TT for road-based EMS (ATT) to a pediatric version (pATT) with a guide containing definitions of triggers.

Methods

The adaption of the ambulance trigger tool to a version suitable for children followed a stepwise manner, including (1) a review of previous literature to pinpoint areas of risk regarding patient safety among children in EMS. (2) Three sessions of expert panel discussions via video meetings were held to evaluate each trigger of the ATT in terms of clinical relevance, comprehensibility, language and areas of risk regarding patient safety among children in EMS. (3) Clinical use of the pATT along with Retrospective Record Review (RRR). (4) Calculation of Item-level validity index and positive predictive value (PPV) for each trigger. (5) calculate inter-rater reliability between two independent record reviewers.

Results

MethodsThe adaption of the ambulance trigger tool to a version suitable for children followed a stepwise manner, including (1) a review of previous literature to pinpoint areas of risk regarding patient safety among children in EMS. (2) Three sessions of expert panel discussions via video meetings were held to evaluate each trigger of the ATT in terms of clinical relevance, comprehensibility, language and areas of risk regarding patient safety among children in EMS. (3) Clinical use of the pATT along with Retrospective Record Review (RRR). (4) Calculation of Item-level validity index and positive predictive value (PPV) for each trigger. (5) calculate inter-rater reliability between two independent record reviewers.

Conclusion

This study demonstrates the adaptation of an existing trigger tool (ATT) to one suitable for children. It also shows that the trigger tool, along with retrospective record review, is a feasible method to evaluate patient safety in EMS, thus complementing existing methods. 

Background

Emergency medical services (EMS) personnel must rapidly assess and transport patients with time-sensitive conditions to optimise patient outcomes. Serum lactate, a valuable in-hospital biomarker, has become more accessible in EMS settings through point-of-care (POC) testing. Although POC lactate levels are valuable in specific patient groups, its broader application in EMS remains unclear. This study assessed the additional predictive value of POC lactate levels in a general adult EMS population.

Methods

This prospective observational study (March 2018 to September 2019) involved two EMS organisations in Västra Götaland, Sweden. Patients were triaged using the Rapid Triage and Treatment System (RETTS). POC lactate levels were measured using StatStrip Xpress devices. Non-consecutive patients who received EMS and were aged 18 years and above were available for inclusion if triaged into RETTS levels: red, orange, yellow, or green if respiratory rate of ≥ 22 breaths/min. Outcomes were adverse outcomes, including a time-sensitive diagnosis, sequential organ failure assessment (SOFA) score ≥ 2, and 30-day mortality. Statistical analyses included descriptive statistics, imputation, and regression models to assess the impact of the addition of POC lactate levels to a base model (comprising patient age, sex, presence of past medical conditions, vital signs, pain, EMS response time, assessed triage condition, and triage level) and a RETTS triage model.

Results

Of 4,546 patients (median age 75 [57, 84] years; 49% male), 32.4% had time-sensitive conditions, 12.5% met the SOFA criteria, and 7.4% experienced 30-day mortality. The median POC lactate level was 1.7 (1.2, 2.5) mmol/L. Patients with time-sensitive conditions had higher lactate levels (1.9 mmol/L) than those with non-time-sensitive conditions (1.6 mmol/L). The probability of a time-sensitive condition increased with increasing lactate level. The addition of POC lactate marginally enhanced the predictive models, with a 1.5% and 4% increase for the base and RETTS triage models, respectively. POC lactate level as a sole predictor showed chance-only level predictive performance.

Conclusions

Prehospital POC lactate assessment provided limited additional predictive value in a general adult EMS population. However, it may be beneficial in specific patient subgroups, emphasizing the need for its judicious use in prehospital settings.

Clinical reasoning and decision-making in prehospital contexts are complex, and patient assessments may be influenced by stress or biases, thus potentially risking patient safety. Previous research has shown mixed results regarding cognitive interventions designed to counteract biases and improve decision-making. In educational settings, there are no tools that assess clinical reasoning while also measuring important decision-making outcomes. This study employed a mixed-methods design and a novel assessment model to evaluate clinical reasoning and decision-making among Swedish prehospital nurse specialists. Additionally, the effect of the metacognitive TWED mnemonic was investigated. Thirteen participants were randomly assigned to two groups and assessed patients in simulation settings, with groups switching cases after brief training on the TWED mnemonic. The primary outcomes included point-based scoring on decision-making, grading of potential risks of patient harm, and analysis of clinical reasoning through reflections. The results showed large variation, without overall differences between groups or demographics. A complex case presentation resulted in lower scores and greater risks of potential patient harm. Qualitative analysis highlighted participants’ ability to handle conflicting data, which correlated with better outcomes. The use of the TWED mnemonic may have increased commission bias. Further research is needed to validate and understand these findings.

Background

Accidental hypothermia is common in all trauma patients and contributes to the lethal diamond, increasing both morbidity and mortality. In hypotensive shock, fluid resuscitation is recommended using fluids with a temperature of 37–42°, as fluid temperature can decrease the patient’s body temperature. In Sweden, virtually all prehospital services use preheated fluids. The aim of the present study was to investigate how the temperature of preheated infusion fluids is affected by the ambient temperatures and flow rates relevant for prehospital emergency care.

Methods

In this experimental simulation study, temperature changes in crystalloids preheated to 39 °C were evaluated. The fluid temperature changes were measured both in the infusion bag and at the patient end of the infusion system. Measurements were conducted in conditions relevant to prehospital emergency care, with ambient temperatures varying between − 4 and 28 °C and flow rates of 1000 ml/h and 6000 ml/h, through an uninsulated infusion set at a length of 175 cm.

Results

The flow rate and ambient temperature affected the temperature in the infusion fluid both in the infusion bag and at the patient end of the system. A lower ambient temperature and lower flow rate were both associated with a greater temperature loss in the infusion fluid.

Conclusion

This study shows that both a high infusion rate and a high ambient temperature are needed if an infusion fluid preheated to 39 °C is to remain above 37 °C when it reaches the patient using a 175-cm-long uninsulated infusion set. It is apparent that the lower the ambient temperature, the higher the flow rate needs to be to limit temperature loss of the fluid.

Background

Emergency Medical Services (EMS) are a unique setting because care for the chief complaint is given across all ages in a complex and high-risk environment that may pose a threat to patient safety. Traditionally, a reporting system is commonly used to raise awareness of adverse events (AEs); however, it could fail to detect an AE. Several methods are needed to evaluate patient safety in EMS. In this light, this study was conducted to (1) develop a national ambulance trigger tool (ATT) with a guide containing descriptions of triggers, examples of use, and categorization of near misses (NMs), no harm incidents (NHIs), and harmful incidents (HIs) and (2) use the ATT on randomly selected ambulance records.

Methods

The ambulance trigger tool was developed in a stepwise manner through (1) a literature review; (2) three sessions of structured group discussions with an expert panel having knowledge of emergency medical service, patient safety, and development of trigger tools; (3) a retrospective record review of 900 randomly selected journals with three review teams from different geographical locations; and (4) inter-rater reliability testing between reviewers.

Results

From the literature review, 34 triggers were derived. After removing clinically irrelevant ones and combining others through three sessions of structured discussions, 19 remained. The most common triggers identified in the 900 randomly selected records were deviation from treatment guidelines (30.4%), the patient is non conveyed after EMS assessment (20.8%), and incomplete documentation (14.4%). The positive triggers were categorized as a near miss (40.9%), no harm (3.7%), and harmful incident (0.2%). Inter-rater reliability testing showed good agreement in both sessions.

Conclusion

This study shows that a trigger tool together with a retrospective record review can be used as a method to measure the frequency of harmful incidents, no harm incidents, and near misses in the EMS, thus complementing the traditional reporting system to realize increased patient safety.

Background

There is a lack of knowledge regarding the epidemiology of severe trauma assessed by Swedish emergency medical services (EMS).

Aim

To investigate the prevalence of trauma in Sweden assessed by EMS from a national perspective and describe patient demography, aetiology, trauma type, prehospital triage and clinical outcomes.

Methods

Data from two national quality registries, the Swedish Ambulance Registry and the Swedish Trauma Registry (SweTrau) were collected from January 1 to December 31, 2019. Inclusion criteria were an Emergency Symptoms and Signs code equivalent to trauma in the Swedish Ambulance Registry and criteria fulfilled for SweTrau inclusion. Exclusion criteria were patients < 18 years old, those not transported to a hospital and those without a personal identification number.

Results

In total, 53,120 patients with trauma were included (14% of primary EMS missions involving a personal identification number). Of those, 2,278 (4.3%) patients (median age: 45 years; 32% women) were reported in SweTrau to have severe or potentially severe trauma (penetrating: 7%, blunt: 93%). In terms of including all causes of trauma, the code for ‘trauma alert activation’ was most frequent (55%). The most frequent injury mechanism was an injury caused by a car (34%). Most (89%) cases were assigned Priority 1 (life-threatening condition) at the dispatch centre. 62% were regarded as potentially life threatening upon EMS arrival, whereas 29% were assessed as non-life-threatening. Overall, 25% of the patients had new injury severity scores > 15. 12% required invasive treatment, 11% were discharged with severe disability and the 30-day mortality rate was 3.6%.

Conclusion

In this cross-sectional study, 14% of the primary EMS missions for one year were caused by trauma. However, only a small proportion of these cases are severe injuries, and the risk of severe disabilities and death appears to be limited. The most frequent aetiology of a severe trauma is injury caused by a car, and most severe traumas are blunt. Severe traumas are given the highest priority at the dispatch centre in the vast majority of cases, but nearly one-third of these cases are considered a low priority by the EMS nurse. The latter leaves room for improvement.

Background

Globally, injuries are a major health problem, and in Sweden, injuries are the second most common reason for ambulance dispatch. However, there is a knowledge gap regarding the epidemiology of injuries requiring assessment by emergency medical services (EMS) in Sweden. The aim of the present study was to describe the prehospital population with injuries that have been assessed and treated by EMS.

Methods

A randomly selected retrospective sample was collected from 1 January through 31 December 2019 in a region in southwestern Sweden. Data were collected from ambulance and hospital medical records.

Results

Among 153,724 primary assignments, 26,697 (17.4%) were caused by injuries. The study cohort consisted of 5,235 patients, of whom 50.5% were men, and the median age was 63 years. The most common cause of injury was low-energy fall (51.4%), and this was the cause in 77.8% of those aged > 63 years and in 26.7% of those aged ≤ 63 years. The injury mechanism was a motor vehicle in 8.0%, a motorcycle in 2.1% and a bicycle in 4.0%. The most common trauma location was the residential area (55.5% overall; 77.9% in the elderly and 34.0% in the younger group). In the prehospital setting, the most frequent clinical sign was a wound (33.2%), a closed fracture were seen in 18.9% and an open fracture in 1.0%. Pain was reported in 74.9% and 42.9% reported severe pain. Medication was given to 42.4% of patients before arrival in the hospital. The most frequent triage colour according to the RETTS was orange (46.7%), whereas only 4.4% were triaged red. Among all patients, 83.6% were transported to the hospital, and 27.8% received fracture treatment after hospital admission. The overall 30-day mortality rate was 3.4%.

Conclusion

Among EMS assignments in southwestern Sweden, 17% were caused by injury equally distributed between women and men. More than half of these cases were caused by low-energy falls, and the most common trauma location was a residential area. The majority of the victims had pain upon arrival of the EMS, and a large proportion appeared to have severe pain.

Background

Breathlessness is a serious and distressing symptom and a common reason why patients require prehospital care by ambulance clinicians. However, little is known about how patients experience this care when they are in a state of breathlessness.

Aim

The aim of this study is to describe the lived experiences of being cared for by ambulance clinicians when experiencing breathlessness.

Methods

Fourteen lifeworld interviews were conducted with patients who experienced breathlessness and were cared for by ambulance clinicians. The interviews were analysed using a qualitative phenomenological approach.

Findings

The essential meaning of being cared for by ambulance clinicians when experiencing breathlessness is described in two ways: existential humanising care, in which the experience is that of being embraced by a genuine presence or existential dehumanising care, in which feeling exposed to an objectifying presence is the main experience. This meaning has four constituents: surrendering to and trusting in the care that will come; being exposed to an objectifying presence is violating; being embraced by a genuine presence is relieving; and knowing is dwelling.

Conclusion

The findings reveal that the ability of ambulance clinicians to provide existential humanising and trustful care, which is the foundation of professional judgement, was essential in how patients responded to and handled the overall situation when breathlessness.