Prehospital Cardiac Care Research Articles

AI Algorithm to Predict Acute Coronary Syndrome in Prehospital Cardiac Care: Retrospective Cohort Study

Background Overcrowding of hospitals and emergency departments (EDs) is a growing problem. However, not all ED consultations are necessary. For example, 80% of patients in the ED with chest pain do not have an acute coronary syndrome (ACS). Artificial intelligence (AI) is useful in analyzing (medical) data, and might aid health care workers in prehospital clinical decision-making before patients are presented to the hospital. Objective The aim of this study was to develop an AI model which would be able to predict ACS before patients visit the ED. The model retrospectively analyzed prehospital data acquired by emergency medical services' nurse paramedics. Methods Patients presenting to the emergency medical services with symptoms suggestive of ACS between September 2018 and September 2020 were included. An AI model using a supervised text classification algorithm was developed to analyze data. Data were analyzed for all 7458 patients (mean 68, SD 15 years, 54% men). Specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for control and intervention groups. At first, a machine learning (ML) algorithm (or model) was chosen; afterward, the features needed were selected and then the model was tested and improved using iterative evaluation and in a further step through hyperparameter tuning. Finally, a method was selected to explain the final AI model. Results The AI model had a specificity of 11% and a sensitivity of 99.5% whereas usual care had a specificity of 1% and a sensitivity of 99.5%. The PPV of the AI model was 15% and the NPV was 99%. The PPV of usual care was 13% and the NPV was 94%. Conclusions The AI model was able to predict ACS based on retrospective data from the prehospital setting. It led to an increase in specificity (from 1% to 11%) and NPV (from 94% to 99%) when compared to usual care, with a similar sensitivity. Due to the retrospective nature of this study and the singular focus on ACS it should be seen as a proof-of-concept. Other (possibly life-threatening) diagnoses were not analyzed. Future prospective validation is necessary before implementation.

Paramedic perspectives on sex and gender equity in prehospital electrocardiogram acquisition

Acute coronary syndrome (ACS) makes up a substantial healthcare burden. Previous research has demonstrated that women fare worse than men across a range of hospital-based ACS processes and outcomes. In the prehospital setting, the 12-lead electrocardiogram (ECG) can identify critical ACS cases and speed access to definitive treatment. However, studies on rates of ECG acquisition among patients at risk of ACS in the prehospital setting have shown that women receive the test less frequently than men. The purpose of this study was to investigate the reasons for observed gender differences in rates of ECG acquisition in the prehospital setting. This is a cross-sectional study of paramedics in an urban emergency medical service agency. An experienced qualitative researcher conducted 26 semi-structured interviews. Using a subjectivist inductive approach, the study team analyzed interview transcripts following the six-step process described by Braun and Clarke (2006). Qualitative rigor was maintained through consistent review, discussion, and revision at each stage. Four themes were identified among diverse views around the 12-lead acquisition. (1) Safety (feelings of physical comfort and psychological safety related to administering a 12-lead). (2) Knowledge (subject-matter knowledge involving the protocols and procedures as well as self-knowledge of participants’ own practice). (3) Training and learning (perceptions of foundational training and on-the-job learning, and how those have influenced their perceptions of how to care for patients experiencing ACS). (4) Professionalism (perceptions of behavior and attitudes and how they influence patient care). These four interrelated themes were integrated to represent a model of prehospital cardiac care. This study addressed a gap in the literature by documenting prehospital providers’ attitudes and beliefs around cardiac care. The resulting model of prehospital cardiac care offers both a template for evaluating the equity of current treatment and a road map for improvement.

Barriers to the implementation of prehospital thrombolysis in the treatment of ST-segment elevation myocardial infarction in South Africa: An exploratory inquiry.

IntroductionEvidence-based guidelines advocate percutaneous coronary intervention (PCI) as the mainstay reperfusion strategy for ST-segment elevation myocardial infarction (STEMI). However, the South African health system is not well positioned to provide PCI as a ‘mainstay strategy’. In response, the Health Professions Council of South Africa approved the use of prehospital thrombolysis (PHT) for emergency care practitioners in 2009. However, since its approval, prehospital thrombolysis has failed to reach a level of systematic uptake indicative of successful implementation. The current study aimed to explore, through a qualitative inquiry, barriers to PHT for the treatment of myocardial infarction within a South African context.MethodsA qualitative single-case study design was used where a series of semi-structured interviews were conducted involving purposefully selected participants. The case comprised a nationalised private emergency medical service, and participants were selected in view of relevant experience and knowledge. Requisite data was conceptualised through the consolidated framework for implementation research, and thematic analysis outlined the data coding procedures of the study.ResultsThe study identified potential barriers to the implementation of PHT. These comprised cost, logistics, inter-professional collaboration, leadership engagement, and beliefs or scepticism associated with PHT.ConclusionA lack of strategic implementation has resulted in a poor introduction of evidenced-based prehospital cardiac care, affecting vulnerable populations who may have otherwise benefited from receiving this level of care. Given the time-sensitive nature of STEMI management, and severely limited access to ‘primary reperfusion’, PHT resembles not only a logical but also appealing solution in the South African context.

Prehospital Cardiac Care: Diagnosis and Management of Acute Chest Pain and Dyspnea

Prehospital Cardiac Care: Diagnosis and Management of Acute Chest Pain and Dyspnea

Increases in survival from out-of-hospital cardiac arrest: A five year study

ObjectiveThis study reports improvements in survival from out-of-hospital cardiac arrest in London over a five year period from 2007 to 2012 and explores the potential reasons for the very striking increases observed. MethodsData from the London Ambulance Service's cardiac arrest registry from 2007 to 2012 were analysed retrospectively for all patients who met the Utstein comparator group criteria (an arrest of a presumed cardiac cause that was bystander witnessed with an initial rhythm of VF/VT). ResultsWe observed an increase in survival from out-of-hospital cardiac arrest during the five year period, with incremental improvements each year from 12% to 32% for the Utstein comparator group of patients. ConclusionWe suggest that a range of important changes made to pre-hospital cardiac care in London over the last five years have contributed to the observed increase in survival over the study period. In addition we advocate a range of further initiatives to continue improving survival from out-of-hospital cardiac arrest.

Ambulance 12-Lead Electrocardiography Transmission via Cell Phone Technology to Cardiologists

This study demonstrates transmission of 12-lead electrocardiography (ECG) in an ambulance to the cell phone of the attendant emergency medical technician and then to the hospital and to cell phones of off-site cardiologists. The emergency medical technician cell phone receives Extensible Markup Language files generated by a Phillips Extensible Markup Language ECG instrument via Wi-Fi-based wireless network and then sends them to an ECG-processing server at the hospital over the mobile telephone network. After reducing ECG noises and artifacts, the server converts files to Digital Imaging and Communications in Medicine-based ECG reports stored in Picture Archiving and Communication System. These reports are sent to the cell phones of off-site cardiologists. Consequently, on-site Emergency Department physicians and off-site cardiologists can discuss ECG reports via Picture Archiving and Communication System on their computers or cell phones to prepare for the most appropriate treatment while the patient is on the way to the hospital. In conclusion, this 12-lead ECG transmission e-technology expands the functions of a 12-lead ECG instrument and facilitates more efficient prehospital cardiac care.

The C. J. Shanaberger Lecture: The Evolution of Prehospital Cardiac Care: 1966–2006 andBeyond

Prehospital cardiac care began 40 year ago. This lecture reviews the origins andevolution of prehospital emergency care for cardiac arrest. Several national andinternational guidelines have defined an evolving standard of care. The most recent guidelines, published in 2005, argue for a return to the basics andemphasize the importance of CPR anddefibrillation. In 40 years we have learned much about the epidemiology of cardiac arrest andthe factors associated with successful resuscitation. Timely CPR anddefibrillation remain the cornerstones of successful therapy. A new role for EMS personnel may help identify at-risk patients andthus prevent future cardiac arrest. A pilot program, know as SPHERE (Supporting Public Health with Emergency Responders) is underway in King County, Washington. The goal is to identify patients with risk factors of high blood pressure or high blood glucose andmotivate the patient to seek follow-up care. Several intervention strategies are being tested. Since EMS providers see up to 10% of the population in any given year the chance to identify at-risk patients provides a public health opportunity.

From the Feds: Research, Programs, and Products

From the Feds: Research, Programs, and Products

The Revolution and Evolution of Prehospital Cardiac Care

Prehospital cardiac care, first established in Belfast, Northern Ireland, in 1966, may be called revolutionary in that it was a radical break from existing practices. The Belfast program "moved" the coronary care unit into the community by treating the early complications of acute myocardial infarcation. The program staffed a mobile coronary care unit with a physician and nurse and demonstrated that patients with out-of-hospital sudden cardiac arrest could be resuscitated. The idea of prehospital cardiac care spread to other countries after publication of the Belfast experience in the Lancet. The first program in the United States, stationed at St Vincent's Hospital in New York, NY, began in 1968 and was modeled after the Belfast program. The physician-staffed model, however, was not widely imitated in the United States. Rather, beginning in 1969, programs using specially trained personnel, know as paramedics, began in Miami, Fla, Seattle, Wash, Columbus, Ohio, Los Angeles, Calif, Portland, Ore, and Nassau County, New York. Paramedic-staffed programs were designed not only to treat early complications of acute myocardial infarction, but also to attempt resuscitation for primary cardiac arrest. Most of the early paramedic programs were based in fire departments. Other programs used private ambulance or police personnel. Prehospital cardiac care has evolved significantly in the past 3 decades. Some notable developments include the tiered response system, training of the general public in cardiopulmonary resuscitation, low-energy defibrillators, automatic external defibrillators, and 12-lead electrocardiographic telemetry. The basic lesson of prehospital cardiac care is that the timely provision of cardiopulmonary resuscitation and defibrillation saves lives.

The revolution and evolution of prehospital cardiac care

The revolution and evolution of prehospital cardiac care

The effect of telemetry on urban prehospital cardiac care

A three-year, controlled trial of the use of telemetry in the prehospital care of cardiac patients was conducted in a major metropolitan area. Five of the ten paramedic squads in the city used telemetry; the other five squads did not. We studied the effect of telemetry on the following: paramedics' abilities to recognize ECGs in a written test; paramedics' abilities to identify ECG arrhythmias in the field; length of time spent by paramedics in the field; survival rates of patients with ventricular fibrillation (VF) cared for by paramedics; abilities of base station physicians to interpret telemetered ECGs; and attitudes of paramedics toward using telemetry. Telemetry was not found to affect the abilities of paramedics to read ECGs in either test or field situations. Paramedics who used telemetry spent more time in the field with their patients than did paramedics who did not use telemetry (P less than .02). We found no statistically significant effect of telemetry on survival rates of VF patients. Using matched ECGs, readings by base station physicians were found to be more accurate than were those by paramedics (P less than .01). Paramedics overwhelmingly reported that telemetry did not help them to save patients' lives, but that it did help them to treat patients with certain arrhythmias. The results suggest that telemetry may not improve either paramedics' abilities to identify arrhythmias or prehospital care for all cardiac patients. The implications for emergency services researchers are discussed.

Effect of telemetry on urban prehospital cardiac care

Effect of telemetry on urban prehospital cardiac care

Prehospital cardiac care: Illusion of consensus

To judge standard practice for managing arrhythmias, what an EMT should be able to do in the field, drugs of choice, the success of EMT training, and the quality of EMT performance, clinical algorithms were developed. Branching logic, forcing yes/no decisions and delineating actions for all contingencies helped formalize and systematize EMT management of urgent and emergency cases. The algorithm set was sent to 19 consultants for review of content, sequence, drug dosage, and drug usage. The results indicated lack of consensus on appropriate prehospital cardiac care, but the approval of the algorithm approach.