Characteristics of and outcome for patients with chest pain in relation to transport by the emergency medical services in a 20-year perspective

Technological development roles and needs in pre-hospital emergency care from the advanced level paramedics' perspective

INTRODUCTION

The work environment of paramedics is rapidly becoming more technology-oriented, and new innovations are constantly being introduced. The aim of this study was to determine the roles Finnish advanced level paramedics identify for themselves within technological development processes in their experience and what kinds of technological development in pre-hospital emergency care are needed.

METHODS

This qualitative study utilised essay material written by experienced advanced level paramedics (n = 20), which was analysed using inductive content analysis.

RESULTS

The paramedics identified direct and indirect roles and clear obstacles. The roles were related to expertise, their own professional skills, supporting development and implementation. The obstacles to participation in technological developed were perceived as the employer's unwillingness to involve grassroots level paramedics, lack of training or expertise, and overall unrecognised role. Technological development was seen to be needed regarding information and communication technology, treatment tools, and equipment. Further, nationally homogenous technological development that supports the quality and safety of nursing work and the integration of digitalization into education were also seen as needed.

CONCLUSIONS

Paramedics can be innovative and active technology developers with extensive expertise in the technology of their field. Employers and technology developers should be encouraged to enable user-oriented product development and to involve paramedics in development work.

Clinical presentation in EMS patients with acute chest pain in relation to sex, age and medical history: prospective cohort study

OBJECTIVE

To assess symptom presentation related to age, sex and previous medical history in patients with chest pain.

DESIGN

Prospective observational cohort study.

SETTING

Two-centre study in a Swedish county emergency medical service (EMS) organisation.

PARTICIPANTS

Unselected inclusion of 2917 patients with chest pain cared for by the EMS during 2018.

DATA ANALYSIS

Multivariate analysis on the association between symptom characteristics, patients' sex, age, previous acute coronary syndrome (ACS) or diabetes and the final outcome of acute myocardial infarction (AMI).

RESULTS

Symptomology in patients assessed by the EMS due to acute chest pain varied with sex and age and also with previous ACS or diabetes. Women suffered more often from nausea (OR 1.6) and pain in throat (OR 2.1) or back (OR 2.1). Their pain was more often affected by palpation (1.7) or movement (OR 1.4). Older patients more often described pain onset while sleeping (OR 1.5) and that the onset of symptoms was slow, over hours rather than minutes (OR 1.4). They were less likely to report pain in other parts of their body than their chest (OR 1.4). They were to a lesser extent clammy (OR 0.6) or nauseous (OR 0.6). These differences were present regardless of whether the symptoms were caused by AMI or not.

CONCLUSIONS

A number of aspects of the symptom of chest pain appear to differ in unselected prehospital patients with chest pain in relation to age, sex and medical history, regardless of whether the chest pain was caused by a myocardial infarction or not. This complicates the possibility in prehospital care of using symptoms to predict the underlying aetiology of acute chest pain.

Prehospital triage of patients with suspected non-ST-segment elevation acute coronary syndrome: Rationale and design of the TRIAGE-ACS study

BACKGROUND

Patients with suspected non-ST-segment elevation acute coronary syndrome (NSTE-ACS) are currently transported and admitted to the nearest emergency department (ED) for risk stratification, diagnostic workup and treatment. Although such patients with NSTE-ACS can benefit from direct transfer to a PCI center for early invasive treatment, no reliable prehospital triage tools are available. Recently, the PreHEART score has been validated in the PreHEART study for prehospital triage of patients with suspected NSTE-ACS.

METHODS

The primary objective of the TRIAGE-ACS study, a prospective cohort study, is to determine whether prehospital triage using the PreHEART score can significantly reduce time from first medical contact to final diagnostics and revascularization in patients in need of coronary revascularization. The first cohort (control cohort; n = 500) is observatory and is used as a reference group for the second cohort. In the second cohort (interventional cohort; n = 500) patients are stratified in the ambulance for direct transfer to either a PCI or a non-PCI center, based on the PreHEART score. These two cohorts will be compared with each other. In total, 1000 patients will be included. Follow-up for endpoints will be performed by reviewing the medical record after 30 days, 1 year, and 2 years.

CONCLUSION

The TRIAGE-ACS study is the first prospective study to investigate the impact of prehospital triage using the PreHEART score on time to final invasive diagnostics and treatment in patients with NSTE-ACS in need of revascularization by transferring high risk patients directly to a PCI center and patients at a low risk of having an NSTE-ACS to a non-PCI center. Such triage strategy could potentially result in optimization of regional care for all ACS patients.

Barriers associated with emergency medical service activation in patients with ST-segment elevation acute coronary syndromes

Many ST-segment elevation acute coronary syndrome (STEACS) patients fail to activate the Emergency Medical System (EMS), with possible dramatic consequences. Prior studies focusing on barriers to EMS activation included patients with any acute coronary syndrome (ACS) without representation of southern European populations. We aimed to investigate the barriers to EMS call for patients diagnosed for STEACS in Italy. A prospective, single-center, survey administered to all patients treated with primary percutaneous coronary intervention for STEACS in a tertiary hospital in northern Italy from 01/06/2018 to 31/05/2020. The questionnaire was filled out by 293 patients. Of these, 191 (65.2%) activated the EMS after symptoms onset. The main reasons for failing to contact EMS were the perception that the symptoms were unrelated to an important health problem (45.5%) and that a private vehicle is faster than EMS to reach the hospital (34.7%). Patients who called a private doctor after symptoms onset did not call EMS more frequently than those who did not and 30% of the patients who did not call the EMS would still act in the same way if a new episode occurred. Previous history of cardiovascular disease was the only predictor of EMS call. Information campaigns are urgently needed to increase EMS activation in case of suspected STEACS and should be primary focused on patients without cardiovascular history, on the misperception that a private vehicle is faster than EMS activation, and on the fact that cardiac arrest occurs early and may be prevented by EMS activation.

The potential of new prediction models for emergency medical dispatch prioritisation of patients with chest pain: a cohort study

Objectives

To develop emergency medical dispatch (EMD) centre prediction models with high sensitivity and satisfying specificity to identify high-priority patients and patients suitable for non-emergency care respectively, when assessing patients with chest pain.

Methods

Observational cohort study of 2917 unselected patients with chest pain who contacted an EMD centre in Sweden due to chest pain during 2018. Multivariate logistic regression was applied to develop models predicting low-risk or high-risk condition, that is, occurrence of time-sensitive diagnosis on hospital discharge.

Results

Prediction models were developed for the identification of patients suitable for high- and low-priority dispatch, using 11 and 10 variables respectively. The area under the receiver-operating characteristic curve (AUROC) for the high-risk prediction model was 0.79 and for the low-risk model it was 0.74. When applying the high-risk prediction model, 56% of the EMS missions were given highest priority, compared with 65% with the current standard. When applying the low-risk model, 7% were given the lowest priority compared to 1% for the current standard. The new prediction models outperformed today’s dispatch priority accuracy in terms of sensitivity as well as positive and negative predictive value in both high- and low-risk prediction. The low-risk model predicted almost six times as many patients as having low-risk conditions compared with today’s standard. This was done without increasing the number of high-risk patients wrongly assessed as low-risk.

Conclusions

By introducing prediction models, based on logistic regression analyses, using variables obtained by standard EMD-questions on age, sex, medical history and symptomology, EMD prioritisation can be improved compared with using current criteria index-based ones. This will allow a more efficient emergency medical services resource allocation.

Incidence, diagnoses and outcomes of ambulance attendances for chest pain: A population-based cohort study

AIMS

Non-traumatic chest pain is one of the most common reasons for calls for emergency assistance and places a significant burden on health services. This study aimed to determine age- and sex-specific incidences, diagnoses, and outcomes of patients with chest pain attended by paramedics using a large population-based sample.

METHODS

Consecutive emergency medical services (EMS) attendances for non-traumatic chest pain in Victoria, Australia from January 2015 to June 2019 were included. Data were individually linked to emergency, hospital admission and mortality records.

RESULTS

During the study period (representing 22,186,930 person-years), chest pain was the reason for contacting EMS in 257,017 of 2,736,570 attendances (9.4%). Overall incidence of chest pain attendances was 1,158 (per 100,000 person-years) with a higher incidence observed with increasing age, among females, among Aboriginal and Torres Strait Islanders, in regional settings, and in socially disadvantaged areas. The most common diagnoses were non-specific pain (46%; 30-day mortality 0.5%), non-ST elevation myocardial infarction (5.3%; mortality 1.3%), pneumonia (3.8%; mortality 3.9%), stable coronary syndromes (3.5%; mortality 0.8%), unstable angina (3.3%; mortality 1.3%), and ST-elevation myocardial infarction (2.8%; mortality 7.0%), while pulmonary embolism (0.7%; mortality 3.2%) and aortic pathologies (0.2%; mortality 22.2%) were rare.

CONCLUSIONS

Chest pain accounts for one in ten ambulance calls, and underlying causes are diverse, with substantial differences according to age and sex. Almost half of patients are discharged from hospital with a diagnosis of non-specific pain and low rates of mortality.

Prehospital risk assessment in patients suspected of non-ST-segment elevation acute coronary syndrome: a systematic review and meta-analysis

OBJECTIVE

To review, inventory and compare available diagnostic tools and investigate which tool has the best performance for prehospital risk assessment in patients suspected of non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

METHODS

Systematic review and meta-analysis. Medline and Embase were searched up till 1 April 2021. Prospective studies with patients, suspected of NSTE-ACS, presenting in the primary care setting or by emergency medical services (EMS) were included. The most important exclusion criteria were studies including only patients with ST-elevation myocardial infarction and studies before 1995, the pretroponin era. The primary end point was the final hospital discharge diagnosis of NSTE-ACS or major adverse cardiac events (MACE) within 6 weeks. Risk of bias was evaluated by the Quality Assessment of Diagnostic Accuracy Studies Criteria.

MAIN OUTCOME AND MEASURES

Sensitivity, specificity and likelihood ratio of findings for risk stratification in patients suspected of NSTE-ACS.

RESULTS

In total, 15 prospective studies were included; these studies reflected in total 26 083 patients. No specific variables related to symptoms, physical examination or risk factors were useful in risk stratification for NSTE-ACS diagnosis. The most useful electrocardiographic finding was ST-segment depression (LR+3.85 (95% CI 2.58 to 5.76)). Point-of-care troponin was found to be a strong predictor for NSTE-ACS in primary care (LR+14.16 (95% CI 4.28 to 46.90) and EMS setting (LR+6.16 (95% CI 5.02 to 7.57)). Combined risk scores were the best for risk assessment in an NSTE-ACS. From the combined risk scores that can be used immediately in a prehospital setting, the PreHEART score, a validated combined risk score for prehospital use, derived from the HEART score (History, ECG, Age, Risk factors, Troponin), was most useful for risk stratification in patients with NSTE-ACS (LR+8.19 (95% CI 5.47 to 12.26)) and for identifying patients without ACS (LR-0.05 (95% CI 0.02 to 0.15)).

DISCUSSION

Important study limitations were verification bias and heterogeneity between studies. In the prehospital setting, several diagnostic tools have been reported which could improve risk stratification, triage and early treatment in patients suspected for NSTE-ACS. On-site assessment of troponin and combined risk scores derived from the HEART score are strong predictors. These results support further studies to investigate the impact of these new tools on logistics and clinical outcome.

FUNDING

This study is funded by ZonMw, the Dutch Organisation for Health Research and Development.

TRIAL REGISTRATION NUMBER

This meta-analysis was published for registration in PROSPERO prior to starting (CRD York, CRD42021254122).

Development of a prehospital prediction model for risk stratification of patients with chest pain

INTRODUCTION

Chest pain is one of the most common reasons for contacting the emergency medical services (EMS). About 15% of these chest pain patients have a high-risk condition, while many of them have a low-risk condition with no need for acute hospital care. It is challenging to at an early stage distinguish whether patients have a low- or high-risk condition. The objective of this study has been to develop prediction models for optimising the identification of patients with low- respectively high-risk conditions in acute chest pain early in the EMS work flow.

METHODS

This prospective observational cohort study included 2578 EMS missions concerning patients who contacted the EMS in a Swedish region due to chest pain in 2018. All the patients were assessed as having a low-, intermediate- or high-risk condition, i.e. occurrence of a time-sensitive diagnosis at discharge from hospital. Multivariate regression analyses using data on symptoms and symptom onset, clinical findings including ECG, previous medical history and Troponin T were carried out to develop models for identification of patients with low- respectively high-risk conditions. Developed models where then tested hold-out data set for internal validation and assessing their accuracy.

RESULTS

Prediction models for risk-stratification based on variables mutual for both low- and high-risk prediction were developed. The variables included were: age, sex, previous medical history of kidney disease, atrial fibrillation or heart failure, Troponin T, ST-depression on ECG, paleness, pain debut during activity, constant pain, pain in right arm and pressuring pain quality. The high-risk model had an area under the receiving operating characteristic curve of 0.85 and the corresponding figure for the low-risk model was 0.78.

CONCLUSIONS

Models based on readily available information in the EMS setting can identify high- and low-risk conditions with acceptable accuracy. A clinical decision support tool based on developed models may provide valuable clinical guidance and facilitate referral to less resource-intensive venues.

Prehospital stratification in acute chest pain patient into high risk and low risk by emergency medical service: a prospective cohort study

OBJECTIVES

To describe contemporary characteristics and diagnoses in prehospital patients with chest pain and to identify factors suitable for the early recognition of high-risk and low-risk conditions.

DESIGN

Prospective observational cohort study.

SETTING

Two centre study in a Swedish county emergency medical services (EMS) organisation.

PARTICIPANTS

Unselected inclusion of 2917 patients with chest pain contacting the EMS due to chest pain during 2018.

PRIMARY OUTCOME MEASURES

Low-risk or high-risk condition, that is, occurrence of time-sensitive diagnosis on hospital discharge.

RESULTS

Of included EMS missions, 68% concerned patients with a low-risk condition without medical need of acute hospital treatment in hindsight. Sixteen per cent concerned patients with a high-risk condition in need of rapid transport to hospital care. Numerous variables with significant association with low-risk or high-risk conditions were found. In total high-risk and low-risk prediction models shared six predictive variables of which ST-depression on ECG and age were most important. Previously known risk factors such as history of acute coronary syndrome, diabetes and hypertension had no predictive value in the multivariate analyses. Some aspects of the symptoms such as pain intensity, pain in the right arm and paleness did on the other hand appear to be helpful. The area under the curve (AUC) for prediction of low-risk candidates was 0.786 and for high-risk candidates 0.796. The addition of troponin in a subset increased the AUC to >0.8 for both.

CONCLUSIONS

A majority of patients with chest pain cared for by the EMS suffer from a low-risk condition and have no prognostic reason for acute hospital care given their diagnosis on hospital discharge. A smaller proportion has a high-risk condition and is in need of prompt specialist care. Building models with good accuracy for prehospital identification of these groups is possible. The use of risk stratification models could make a more personalised care possible with increased patient safety.

Caring approach for patients with chest pain - Swedish registered nurses' lived experiences in Emergency Medical Services

Purpose: Encountering patients with chest pain iscommon for Registered Nurses (RNs) in Emergency Medical Services (EMS) who are responsible for the patient’s medical and nursing care . From a lifeworld perspective, bodily illness is related to existential suffering, requiring knowledge to asses the situation from a holistic perspective . The aim of this study is to describe the caring approach when RNs encounter patients with chest pain.

Methods: A phenomenological methodology to capture RNs’ lived experiences was chosen. Seven qualitative in-depth interviews were conducted at three ambulance stations in Sweden.

Results: The essence of the caring approach while encountering patients with chest pain comprises two constituents; “trust based on confidence and competence” and “the collegial striving towards the best possible care”. Trust is two-parted; trust in oneself, and striving towards gaining the patient’s trust . Competence and experience when combined, develop into confidence especially in stressful situations. The caring approach is nurtured in a well-functioning collegial team.

Conclusions: This study contributes to understanding the caring approach based on the specific patient’s lifeworld in holistic EMS care. By trusting oneself, the patient, and one’s colleague, RNs in EMS shift focus from medical-orientated care to a holistic lifeworld caring approach. . More research is needed on trust as a phenomenon in EMS, both from caregivers’ and patients’ perspectives.

The intensity of pain in the prehospital setting is most strongly reflected in the respiratory rate among physiological parameters

BACKGROUND

In order to treat pain optimally, the Emergency Medical Service (EMS) clinician needs to be able to make a reasonable estimation of the severity of the pain. It is hypothesised that various physiological parameters will change as a response to pain.

AIM

In a cohort of patients who were seen by EMS clinicians, to relate the patients' estimated intensity of pain to various physiological parameters.

METHODS

Patients who called for EMS due to pain in a part of western Sweden were included. The intensity of pain was assessed according to the visual analogue scale (VAS) or the Numerical Rating Scale (NRS). The following were assessed the same time as pain on EMS arrival: heart rate, systolic and diastolic blood pressure, respiratory rate, moist skin and paleness.

RESULTS

In all, 19,908 patients (≥18 years), were studied (51% women). There were significant associations between intensity of pain and the respiratory rate (r = 0.198; p < 0.0001), heart rate (r = 0.037; p < 0.0001), systolic blood pressure (r = -0.029; p < 0.0001), moist skin (r = 0.143; p < 0.0001) and paleness (r = 0.171; p < 0.0001). The strongest association was found with respiratory rate among patients aged 18-64 years (r = 0.258; p < 0.0001).

CONCLUSION

In the prehospital setting, there were significant but weak correlations between intensity of pain and physiological parameters. The most clinically relevant association was found with an increased respiratory rate and presence of pale and moist skin among patients aged < 65 years. Among younger patients, respiratory rate may support in the clinical evaluation of pain.

Association between the reported intensity of an acute symptom at first prehospital assessment and the subsequent outcome: a study on patients with acute chest pain and presumed acute coronary syndrome

BACKGROUND

To decrease the morbidity burden of cardiovascular disease and to avoid the development of potentially preventable complications, early assessment and treatment of acute coronary syndrome (ACS) are important. The aim of this study has therefore been to explore the possible association between patients' estimated intensity of chest pain when first seen by the ambulance crew in suspected ACS, and the subsequent outcome before and after arrival in hospital.

METHODS

Data was collected both prospectively and retrospectively. The inclusion criteria were chest pain raising suspicion of ACS and a reported intensity of pain ≥4 on the visual analogue scale.

RESULTS

All in all, 1603 patients were included in the study. Increased intensity of chest pain was related to: 1) more heart-related complications before hospital admission; 2) a higher proportion of heart failure, anxiety and chest pain after hospital admission; 3) a higher proportion of acute myocardial infarction and 4) a prolonged hospitalisation. However, there was no significant association with mortality neither in 30 days nor in three years. Adjustment for possible confounders including age, a history of smoking and heart failure showed similar results.

CONCLUSION

The estimated intensity of chest pain reported by the patients on admission by the ambulance team was associated with the risk of complications prior to hospital admission, heart failure, anxiety and chest pain after hospital admission, the final diagnosis and the number of days in hospital.

TRIAL REGISTRATION

ClinicalTrials.gov 151:2008/4564 Identifier: NCT00792181. Registred 17 November 2008 'retrospectively registered'.

Prehospital triage of patients diagnosed with perforated peptic ulcer or peptic ulcer bleeding: an observational study of patients calling 1-1-2

BACKGROUND

Triage systems are used in emergency medical services to systematically prioritize prehospital resources according to individual patient conditions. Previous studies have shown cases of preventable deaths in emergency medical services even when triage systems are used, indicating a potential undertriage among some conditions. The aim of this study was to investigate the triage level among patients diagnosed with perforated peptic ulcer (PPU) or peptic ulcer bleeding (PUB).

METHODS

In a three-year period in Central Denmark Region, all patients hospitalized within 24 h after a 1-1-2 emergency call and who subsequently received either a PPU or a PUB (hereinafter combined and referred to as PPU/PUB) or a First Hour Quintet (FHQ: respiratory failure, stroke, trauma, cardiac chest pain, and cardiac arrest) diagnosis were investigated. A modified Poisson regression was used to estimate the relative risk of receiving the highest and lowest prehospital response level. Also, a linear regression analysis was used to estimate the relative risk of 30-day mortality.

RESULTS

Of 8658 evaluated patients, 263 were diagnosed with PPU/PUB. After adjusting for relevant confounding variables, patients diagnosed with PPU/PUB were less likely to receive ambulance transportation compared to patients diagnosed with stroke, RR = 1.41 (CI: 1.28-1.56); trauma, RR = 1.28 (CI: 1.15-1.42); cardiac chest pain, RR = 1.47 (CI: 1.33-1.62); and cardiac arrest, RR = 1.44 (CI: 1.31-1.42). Among patients diagnosed with PPU/PUB, 6.5% (CI: 3.3-9.7) did not receive ambulance transportation. The proportion of patients not receiving ambulance transportation was higher among patients diagnosed with PPU/PUB compared to patients diagnosed with an FHQ diagnosis. The 30-day mortality rate among patients diagnosed with PPU/PUB was 7.8% (CI: 4.2-11.1). This was lower than the 30-day mortality rate among patients diagnosed with respiratory failure (P = 0.010), stroke (P = 0.001), and cardiac arrest (P < 0.001), but comparable to the 30-day mortality among patients diagnosed with cardiac chest pain (P = 0.080) and trauma (P = 0.281).

CONCLUSION

Among patients calling 1-1-2, fewer patients diagnosed with PPU/PUB received ambulance transportation than patients diagnosed with FHQ diagnoses, despite a high mortality among patients diagnosed with PPU/PUB.

Oxygen Therapy in Suspected Acute Myocardial Infarction

BACKGROUND

The clinical effect of routine oxygen therapy in patients with suspected acute myocardial infarction who do not have hypoxemia at baseline is uncertain.

METHODS

In this registry-based randomized clinical trial, we used nationwide Swedish registries for patient enrollment and data collection. Patients with suspected myocardial infarction and an oxygen saturation of 90% or higher were randomly assigned to receive either supplemental oxygen (6 liters per minute for 6 to 12 hours, delivered through an open face mask) or ambient air.

RESULTS

A total of 6629 patients were enrolled. The median duration of oxygen therapy was 11.6 hours, and the median oxygen saturation at the end of the treatment period was 99% among patients assigned to oxygen and 97% among patients assigned to ambient air. Hypoxemia developed in 62 patients (1.9%) in the oxygen group, as compared with 254 patients (7.7%) in the ambient-air group. The median of the highest troponin level during hospitalization was 946.5 ng per liter in the oxygen group and 983.0 ng per liter in the ambient-air group. The primary end point of death from any cause within 1 year after randomization occurred in 5.0% of patients (166 of 3311) assigned to oxygen and in 5.1% of patients (168 of 3318) assigned to ambient air (hazard ratio, 0.97; 95% confidence interval [CI], 0.79 to 1.21; P=0.80). Rehospitalization with myocardial infarction within 1 year occurred in 126 patients (3.8%) assigned to oxygen and in 111 patients (3.3%) assigned to ambient air (hazard ratio, 1.13; 95% CI, 0.88 to 1.46; P=0.33). The results were consistent across all predefined subgroups.

CONCLUSIONS

Routine use of supplemental oxygen in patients with suspected myocardial infarction who did not have hypoxemia was not found to reduce 1-year all-cause mortality. (Funded by the Swedish Heart-Lung Foundation and others; DETO2X-AMI ClinicalTrials.gov number, NCT01787110 .).

Long-Term Mortality of Emergency Medical Services Patients

STUDY OBJECTIVE

Emergency medical services (EMS) provides out-of-hospital care to patients with life-threatening conditions, but the long-term outcomes of EMS patients are unknown. We seek to determine the long-term mortality of EMS patients in Denmark.

METHODS

We analyzed linked EMS, hospital, and vital status data from 3 of 5 geographic regions in Denmark. We included events from July 1, 2011, to December 31, 2012. We classified EMS events according to primary dispatch category (unconsciousness/cardiac arrest, accidents/trauma, chest pain, dyspnea, neurologic symptoms, and other EMS patients). The primary outcome was 1-year mortality adjusted for age, sex, and Charlson comorbidity index.

RESULTS

Among 142,125 EMS events, primary dispatch categories were unconsciousness or cardiac arrest 5,563 (3.9%), accidents or trauma 40,784 (28.7%), chest pain 20,945 (14.7%), dyspnea 9,607 (6.8%), neurologic symptoms 17,804 (12.5%), and other EMS patients 47,422 (33.4%). One-year mortality rates were unconscious or cardiac arrest 54.7% (95% confidence interval [CI] 53.4% to 56.1%), accidents or trauma 7.8 (95% CI 7.5% to 8.1%), chest pain 8.5% (95% CI 8.1% to 9.0%), dyspnea 27.7% (95% CI 26.7% to 28.7%), neurologic symptoms 14.1% (95% CI 13.6% to 14.7%), and other EMS patients 11.1% (95% CI 10.8% to 11.4%). Compared with other EMS conditions, adjusted 1-year mortality was higher in unconsciousness or cardiac arrest (risk ratio [RR] 2.6; 95% CI 2.5 to 2.7), dyspnea (RR 1.5; 95% CI 1.4 to 1.5), and in neurologic symptoms (RR 1.1; 95% CI 1.0 to 1.1), but lower in chest pain (RR 0.6; 95% CI 0.6 to 0.7) and accidents or trauma (RR 0.8; 95% CI 0.8 to 0.8).

CONCLUSION

EMS patients with unconsciousness or cardiac arrest, dyspnea, and neurologic symptoms are at highest risk of long-term mortality. Our results suggest a potential for outcome improvement in these patients.

Possible effects of a course in cardiovascular nursing on prehospital care of patients experiencing suspected acute coronary syndrome: a cluster randomised controlled trial

BACKGROUND

Current research suggests that nurses can influence the outcome for patients with acute coronary syndrome (ACS). The aim of this study has been to evaluate whether a course in cardiovascular nursing (CVN) can improve ambulance nurses' (ANs') prehospital care of patients experiencing suspected ACS, related to pain intensity.

METHODS

This is a cluster randomised controlled trial that was conducted in the ambulance services. Patients were allocated to one of two groups: in the first group, patients were treated by ANs who had attended the CVN course and in the second group patients were treated by ANs without this qualification. Inclusion criteria were: 1/pain raising suspicion of ACS, and 2/pain score ≥4 on a visual analogue scale (VAS). The primary outcome was the estimated intensity of pain or discomfort according to VAS 15 min after randomisation. Secondary outcomes were estimated intensity of pain or discomfort on admission to hospital and further requirement of pain treatment, as well as symptoms such as paleness and/or cold sweat; nausea and/or vomiting; anxiety, dyspnea, degree of alertness, respiratory depression and aggressiveness. A further secondary outcome measured was survival to 30 days. Lastly, a final diagnosis was made. A total of 38 ANs attended the CVN course. There were 1,747 patients who fulfilled the inclusion criteria.

RESULTS

The pain score did not differ significantly between the two groups fifteen minutes after randomisation (median value of VAS was 4.0 in both groups). On admission to hospital the pain score was significantly lower for patients treated by an AN who had attended the CVN course (n = 332) compared with those treated by an AN who had not attended the course (n = 1,415) (median 2.5 and 3.0 respectively, p = 0.001). The ANs who had attended the course used higher doses of morphine.

CONCLUSIONS

An educational intervention with a CVN course did not relate significantly to more efficient pain relief in suspected ACS during the first 15 min. However, this intervention was associated with more effective pain relief later on in the prehospital setting. Thus, a CVN course for ANs appears to be associated with reduced pain intensity among patients experiencing suspected ACS. This result needs however to be confirmed in further trials.

TRIAL REGISTRATION

The ClinicalTrials.gov Protocol Registration System (registration number NCT00792181).

Could prioritisation by emergency medicine dispatchers be improved by using computer-based decision support? A cohort of patients with chest pain

BACKGROUND

To evaluate whether a computer-based decision support system could improve the allocation of patients with acute coronary syndrome (ACS) or a life-threatening condition (LTC). We hypothesised that a system of this kind would improve sensitivity without compromising specificity.

METHODS

A total of 2285 consecutive patients who dialed 112 due to chest pain were asked 10 specific questions and a prediction model was constructed based on the answers. We compared the sensitivity of the dispatchers' decisions with that of the model-based decision support model.

RESULTS

A total of 2048 patients answered all 10 questions. Among the 235 patients with ACS, 194 were allocated the highest prioritisation by dispatchers (sensitivity 82.6%) and 41 patients were given a lower prioritisation (17.4% false negatives). The allocation suggested by the model used the highest prioritisation in 212 of the patients with ACS (sensitivity of 90.2%), while 23 patients were underprioritised (9.8% false negatives). The results were similar when the two systems were compared with regard to LTC and 30-day mortality. This indicates that computer-based decision support could be used either for increasing sensitivity or for saving resources. Three questions proved to be most important in terms of predicting ACS/LTC, [1] the intensity of pain, [2] the localisation of pain and [3] a history of ACS.

CONCLUSION

Among patients with acute chest pain, computer-based decision support with a model based on a few fundamental questions could improve sensitivity and reduce the number of cases with the highest prioritisation without endangering the patients.

Prehospital factors associated with an acute life-threatening condition in non-traumatic chest pain patients - A systematic review

BACKGROUND

Chest pain is a common symptom among patients contacting the emergency medical services (EMS). Risk stratification of these patients is warranted before arrival in hospital, regarding likelihood of an acute life-threatening condition (LTC).

AIM

To identify factors associated with an increased risk of acute LTC among patients who call the EMS due to non-traumatic chest pain.

METHODS

Several databases were searched for relevant articles. Identified articles were quality-assessed using the Scottish Intercollegiate Guidelines Network checklists. Extracted data was analysed using a semi-quantitative synthesis evaluating the level of evidence of each identified factor.

RESULTS

In total, 10 of 1245 identified studies were included. These studies provided strong evidence for an increased risk of an acute LTC with increasing age, male gender, elevated heart rate, low systolic blood pressure and ST elevation or ST depression on a 12-lead ECG. The level of evidence regarding the history of myocardial infarction, angina pectoris or presence of a Q wave or a Left Bundle Branch Block on the ECG was moderate. The evidence was inconclusive regarding dyspnoea, cold sweat/paleness, nausea/vomiting, history of chronic heart failure, smoking, Right Bundle Branch Block or T-inversions on the ECG.

CONCLUSIONS

Factors reflecting age, gender, myocardial ischemia and a compromised cardiovascular system predicted an increased risk of an acute life-threatening condition in the prehospital setting in cases of acute chest pain. These factors may form the basis for prehospital risk stratification in acute chest pain.

Chest pain prevalence, causes, and disposition in the emergency department of a regional hospital in Pretoria

Background

Chest pain is a common clinical syndrome. However, there is a paucity of African studies describing the causes, prevalence, aetiology, and disposition of patients with chest pain presenting in the emergency department (ED).

Aim

The aim of this retrospective descriptive study was to determine the prevalence, causes, demographics, and disposition of all adult patients with the main complaint of chest pain presenting at the ED of a regional hospital in South Africa.

Methods

Records of all patients 18 years and older presenting with the complaint of chest pain from 1 December 2011 through 10 April 2012 were assessed. A data collection sheet capturing patient demographics and disposition from the ED was used. The diagnosis was subdivided into groups: cardiovascular, respiratory, gastrointestinal, musculoskeletal, psychiatric/psychogenic, other, and unknown.

Results

Of the 312 patients presenting with chest pain, 210 patient files were retrieved. The prevalence of non-traumatic chest pain was 1.66%. Respiratory disease was the most common cause (36.19%), with pneumonia the most common diagnosis (24.40%). Logistic regression showed diagnoses of acute cardiovascular disease or respiratory disease, older age, and transport by ambulance as being associated with admission.

Conclusion

The main cause of acute chest pain was found to be respiratory disease, followed by musculoskeletal disorders. In the African context, the aetiology of acute chest pain differs from that in first world countries. Health workers should therefore pay special attention to respiratory conditions during diagnosis and management in African patients with acute chest pain.

[Acute pain in myocardial infarction: analysis of concept]

OBJECTIVE

To analyze the concept "sharp pain" in the context of acute myocardial infarction.

METHODS

Conceptual analysis method proposed by Walker and Avant. This makes it possible to clarify the concept of attributes. We conducted an integrative review to assist the search of studies published in 2006 and 2012, using the descriptors 'Acute Pain' and 'myocardial infarction', through consultation to Cumulative Index to Nursing and Allied Health Literature (CINAHL), Scopus and Public/Publish Medline (PubMed) data.

RESULTS

A sample of 29 studies was selected in which the background identified was: reduction of myocardial perfusion and/or death of myocardial tissue; attributes: quality, location, time, duration and irradiation; and consequent: report of pain, dyspnea, high heart rate, nausea, vomiting, high blood pressure, high respiratory rate, sleep disturbance, diaphoresis, fatigue, paleness, weakness, anxiety and fear.

CONCLUSION

The findings have clarified the attributes of the concept sharp pain in myocardial infarction.

Mass Media Campaigns' Influence on Prehospital Behavior for Acute Coronary Syndromes: An Evaluation of the Australian Heart Foundation's Warning Signs Campaign

Background

The aim of this study was to examine the awareness of a recent mass media campaign, and its influence on knowledge and prehospital times, in a cohort of acute coronary syndrome (ACS) patients admitted to an Australian hospital.

Methods and Results

We conducted 199 semistructured interviews with consecutive ACS patients who were aged 35 to 75 years, competent to provide consent, and English speaking. Questions addressed the factors known to predict prehospital delay, awareness of the campaign, and whether it increased knowledge and influenced actions. Multivariable logistic regression was used to examine the association between campaign awareness and a 1-hour delay in deciding to seek medical attention (patient delay) and a 2-hour delay in presenting to hospital (prehospital delay). The median age was 62 years (IQR=53 to 68 years), and 68% (n=136) were male. Awareness of the campaign was reported by 127 (64%) patients, with most of these patients stating the campaign (1) increased their understanding of what is a heart attack (63%), (2) increased their awareness of the signs and symptoms of heart attack (68%), and (3) influenced their actions in response to symptoms (43%). After adjustment for other predictors, awareness of the campaign was significantly associated with patient delay time of ≤1 hour (adjusted odds ratio [AOR]=2.25, 95% CI: 1.03 to 4.91, P=0.04) and prehospital delay time ≤2 hours (AOR=3.11, 95% CI: 1.36 to 7.08, P=0.007).

Conclusions

Our study showed reasonably high awareness of the warning signs campaign, which was significantly associated with shorter prehospital decision-making and faster presentation to hospital.

Characteristics and outcome among patients who dial for the EMS due to chest pain

OBJECTIVES

This study aims to describe patients who called for the emergency medical service (EMS) due to chest discomfort, in relation to gender and age.

METHODS

All patients who called the emergency dispatch centre of western Sweden due to chest discomfort, between May 2009 and February 2010, were included. Initial evaluation, aetiology and outcome are described as recorded in the databases at the dispatch centre, the EMS systems and hospitals. Patients were divided into the following age groups: ≤50, 51-64 and ≥65 years.

RESULTS

In all, 14,454 cases were enrolled. Equal proportions of men (64%) and women (63%) were given dispatch priority 1. The EMS clinicians gave priority 1 more frequently to men (16% versus 12%) and older individuals (10%, 15% and 14%, respective of age group). Men had a significantly higher frequency of central chest pain (83% versus 81%); circulatory compromise (34% versus 31%); ECG signs of ischaemia (17% versus 11%); a preliminary diagnosis of acute coronary syndrome (40% versus 34%); a final diagnosis of acute myocardial infarction (14% versus 9%) and any potentially life-threatening condition (18% versus 12%). Individuals aged ≥65 years were given a lower priority than individuals aged 51-64 years, despite poorer characteristics and outcome. In all, 78% of cases with a potentially life-threatening condition and 67% of cases that died within 30 days of enrolment received dispatch priority 1. Mortality at one year was 1%, 4% and 18% in each individual age group.

CONCLUSION

Men and the elderly were given a disproportionately low priority by the EMS.

DETermination of the role of OXygen in suspected Acute Myocardial Infarction trial

BACKGROUND

The use of supplemental oxygen in the setting of suspected acute myocardial infarction (AMI) is recommended in international treatment guidelines and established in prehospital and hospital clinical routine throughout the world. However, to date there is no conclusive evidence from adequately designed and powered trials supporting this practice. Existing data are conflicting and fail to clarify the role of supplemental oxygen in AMI.

METHODS

A total of 6,600 normoxemic (oxygen saturation [SpO2] ≥90%) patients with suspected AMI will be randomly assigned to either supplemental oxygen 6 L/min delivered by Oxymask (MedCore Sweden AB, Kista, Sweden) for 6 to 12 hours in the treatment group or room air in the control group. Patient inclusion and randomization will take place at first medical contact, either before hospital admission or at the emergency department. The Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies registry will be used for online randomization, allowing inclusion of a broad population of all-comers. Follow-up will be carried out in nationwide health registries and Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies. The primary objective is to evaluate whether oxygen reduces 1-year all-cause mortality. Secondary end points include 30-day mortality, major adverse cardiac events, and health economy. Prespecified subgroups include patients with confirmed AMI and certain risk groups. In a 3-month pilot study, the study concept was found to be safe and feasible.

CONCLUSION

The need to clarify the uncertainty of the role of supplemental oxygen therapy in the setting of suspected AMI is urgent. The DETO2X-AMI trial is designed and powered to address this important issue and may have a direct impact on future recommendations.