Prehospital care of acute myocardial infarction

Gender Disparities in Common Sense Models of Illness Among Myocardial Infarction Victims

Symptom attributions were contrasted between male and female myocardial infarction victims (N = 157) who were comparable on age, cardiac risk status, medical history, symptom presentation, and other variables. Women were less likely than men to attribute their prehospital symptoms to cardiac causes. In the context of hearing symptom attributions or advice from support persons, women were less likely than men to report receiving a cardiac attribution or advice to seek medical attention. Results have implications for how victim gender influences the lay interpretation of cardiac symptoms.

The structure of emotions during acute myocardial infarction: a model of coping

The present state of medical care for heart attacks, or acute myocardial infarction (AMI), clearly indicates that rapidly and expeditiously seeking definitive medical care will reduce morbidity and prevent mortality. Despite the clearly established advantages of rapid AMI treatment, the time from the onset of acute symptoms of AMI to definitive medical care is often prolonged and individuals with a prior history of AMI and/or coronary artery disease (CAD) extend care-seeking. Behaviors and actions surrounding acute care-seeking are often fraught with complex social, psychological and emotional processes. The purpose of the present paper is to bring together a theoretical and an applied understanding of the interval of time from acute symptom onset to definitive medical care during AMI; and to understand the role of emotions in the care-seeking process. This task is especially important among individuals with a prior history of AMI and/or CHD. These individuals can be seen as experiencing a "spectrum of posttraumatic disturbances", ranging from anxiety to posttraumatic stress disorder and alexithymia. These disturbances contribute to extended care-seeking thereby placing the individuals at greater risk for AMI and sudden cardiac death. Effective intervention requires three elements. First, knowledge is necessary so that individual and lay others can correctly label symptoms and signs of an AMI. Second, it is necessary to provide feasible behaviors that individuals and lay others can use to access definitive medical care. Third, and perhaps most importantly, it is necessary to provide understanding of and skills to cope with the emotional arousal surrounding both the primary traumatic experience of symptoms and signs, potential secondary traumatic consequences of AMI care-seeking and tertiary trauma from the long-term consequences of CHD.

Complications from i.v. therapy: results from field-started and emergency department-started i.v.'s compared

Because the complications resulting from IV therapy started outside the hospital seem inordinately higher than those resulting from IV therapy started in the emergency department, we undertook a comparative two-month study of the complications resulting from both sources. We found the number and severity of complications from IV therapy started in the field significantly greater than complications from that started in the ED. The phlebitis rate in the prehospital group was 4.65 times that in the ED group (P less than .001). The percentage of patients with unexplained fever in the prehospital group was 5.58 times that in the ED group (P less than .01). Means for reducing the complications and areas for further research are suggested.

The impact of the family and lay others on care-seeking during life-threatening episodes of suspected coronary artery disease

To understand the impact of the family on care-seeking during a suspected episode of acute coronary artery disease (CAD) interviews were conducted with 1102 individuals hospitalized for a suspected myocardial infarction. Analyzing the care-seeking behavior of these individuals within life threatening illness behavior and situational perspectives, bivariate and multivariate analyses revealed that family members, especially a spouse, had both positive and negative influences on the duration of time between acute symptom onset and arrival at a hospital emergency room. To reduce both the morbid and mortal consequences of acute CAD it is recommended that we direct our intervention efforts toward warning the public of situational circumstances which contribute to extended self treatment and evaluation during acute episodes of CAD.

Cardiovascular responses to early exercise in inferior wall ST acute myocardial infarction

The heart rate and blood pressure responses to standardized exercise tests were studied in a group of patients with electrocardiographic evidence of inferior wall acute myocardial infarction (AMI). The tests were done on a bicycle ergometer at 8 to 10 days and 10 to 12 weeks after AMI. At 8 to 10 days after AMI, those with ST AMI (n = 12) had a significantly reduced heart rate response to exercise compared with patients with Q-wave AMI (n = 25). This difference was not evident at 10 to 12 weeks. The systolic blood pressure response in patients with ST AMI was lower than that of Q-wave AMI patients during the first exercise test, although the difference did not attain statistical significance but was significantly lower than the responses of both groups at the second test. The patients with ST AMI had smaller amounts of myocardial damage than those with Q-wave AMI as indicated by plasma creatine kinase values (p less than 0.01). These differences in the heart rate responses appeared to result from the preferential activation of nonmyelinated afferent fibers in the subepicardial region of the inferior wall of the myocardium.

The state of school heart health education: a review of the literature

The evidence and presence of modifiable risk factors associated with heart disease has heightened interest among health educators in developing prevention oriented programs. In an attempt to assist in planning future curriculum efforts and research in this area a literature review was conducted. It is presented and organized within the following three major categories: 1. incidence of cardiovascular risk factors (in the school age population); 2. need for health education (the status of adolescent health and problems of motivation); and 3. evaluations of current heart projects (knowledge, attitudes and behavioral outcomes). A few classic articles were included: the primary literature reviewed was that of the past 10 years. The following conclusions were drawn: 1. there is a need to be concerned about the cardiovascular health of young people; 2. the need for educational programs about proven methods of prevention is well documented; 3. studies have found that adolescents do not have sufficient knowledge upon which to make healthful decisions related to preventing cardiovascular disease; 4. research has demonstrated that well designed programs can be effective in increasing health knowledge and promoting positive attitudes; 5. some programs have encouraged behavioral change; 6. most programs have proven too expensive to become integral components of the curricula; and 7. further educational research must be conducted so that health education might by the end of this decade play a significant role in the reduction of the morbidity and mortality inflicted by cardiovascular disease.

Follow-up of 514 consecutive patients with cardiopulmonary arrest outside the hospital

During the years 1974 of 1976, 514 patients with prehospital cardiopulmonary arrest were brought to the Hennepin County Medical Center (HCMC) Emergency Department. Of these, 344 patients (67%) were either dead on arrival or died in the emergency department despite efforts at resuscitation. The remaining 170 patients were admitted to the coronary care unit. Eighty-seven patients (51%) died in the coronary care unit, primarily from uncontrolled rhythm disturbances and/or cardiogenic shock. The remaining 83 patients (16% of the total group, 49% of those admitted to the hospital) were discharged alive from HCMC. In this group, 49 patients of the 83 long-term survivors were ambulatory with full mental function when discharged. The remaining 34 patients were trnasferred to chronic care facilities for medical treatment of on-going problems. Of the 49 ambulatory patients, satisfactory data for follow-up was obtained on 47. Their mortality rate was 15% in the first year and 50% in the second, primarily from sudden death syndrome.

Atropine-induced ventricular fibrillation: case report and review of the literature

A bradycardic and mildly hypotensive acute myocardial infarction patient developed sinus tachycardia, ventricular tachycardia, flutter, and fibrillation following intravenous atropine. Previous case reports are reviewed and the literature regarding the advisability of this mode of therapy is discussed. In the light of conflicting opinion as to the necessity of atropine in the mildly hypotensive and bradycardic acute myocardial infarction patient, and in view of its potentially deliterious effects on ischemic myocardium, a cautious and selective application of this drug is advised.

Prehospital and hospital coronary care

This article reviews the current state of services for coronary care. Since the majority of deaths from coronary heart disease occur early and outside the hospital, the importance of the prehospital phase is emphasized. The delay in this period, which is very dangerous for the patient, should be reduced and mobile coronary care units (MCCU's) are one possibility to reduce the rate of sudden coronary death. Different systems of MCCU's are discussed: (1) those based on a hospital coronary care unit, usually accompanied by a nurse and/or a doctor and (2) those integrated into an already existing decentralized emergency system (e.g. fire department) run by paramedics. Although long-term survival of patients resuscitated from ventricular fibrillation is not so good, the results of many of these units are remarkable.

Factors in successful resuscitation by paramedics

The out-of-hospital reports of 2152 consecutive paramedic fire rescue responses were reviewed. Examination of emergency department records and outcome was conducted in all cardiopulmonary arrests (120), major trauma (59) or nontraumatic hemorrhage (9) and one half (95 of 199 patients) with chest pain or possible myocardial infarction. Predominant age was 50 to 70 (66%) and men outnumbered women by four to one. At the scene arrival was under five minutes in over 70% of the cases. Thirty of the 120 patients with cardiopulmonary arrest (12 occurred after paramedic arrival) responded to initial cardiopulmonary resuscitation, 24 patients entered the coronary care unit, and 16 were discharged alive. Ventricular fibrillation (50) and asystole (40) were the documented rhythms. All survivors had ventricular fibrillation. Evaluation of the trauma and nontraumatic blood loss victims indicated that, after the paramedic places an intravenous line, the paramedic role is less well defined. Mean transportation time was 36 (trauma) and 38 (hemorrhage) minutes to the hospital.

Blind defibrillation outside the hospital

Blind defibrillation, defibrillation of an unconscious, pulseless adult without electrocardiographic verification of arrhythmia, allows early definitive treatment of cardiac arrest victims. Basic EMT-As have the ability to perform blind defibrillation in a prehospital setting, and place an esophageal obturator airway. When basic EMT-As are performing blind defibrillation, there should be a standard operating procedure involving diagnosis, defibrillation, CPR and re-evaluation.

New observations on the effects of atropine on the sinoatrial and atrioventricular nodes in man

Previous observations of slowing of the heart rate after administration of atropine in doses smaller than 0.4 mg and recent reports of development of rhythm disorders in patients with acute myocardial infarction given atropine prompted us to evaluate systematically the effects of various doses of atropine (0.1 to 0.8 mg) on the response of the sinoatrial (S-A) and atrioventricular (A-V) nodes in healthy volunteers. The response of the S-A node to atropine was characteristically bimodal, slowing at smaller doses and accelerating at larger doses. In contrast, the A-V node showed acceleration of conduction in response to all doses of atropine used. A hypothesis based on current understanding of the electrophysiologic parameters governing impulse formation and impulse conduction is advanced to explain the apparent paradox in the S-A and A-V nodal responses to small doses of atropine. The results suggest the need for caution and continuous rhythm monitoring when giving atropine to patients with acute myocardial infarction.

Reduction of prehospital, ambulance and community coronary death rates by the community-wide emergency cardiac care system

Initiation of quick prehospital cardiopulmonary resuscitation and emergency cardiac care completed the total system needed to provide emergency and convalescent coronary care for a community. Subsequently, annual community rates for coronary death during ambulance transport fell by 62 per cent and for prehospital coronary death by 26 per cent in people under 70 years of age. In cardiac arrest due to acute myocardial infarction, prompt successful prehospital correction of ventricular fibrillation and asystole yielded long-term survival in two thirds of cases. This 66 per cent success rate of prehospital cardiopulmonary resuscitation and emergency cardiac care is identical to contemporary international experience. Precordial thump-version with the fist and precordial fist pacing appeared logical additions to prehospital cardiopulmonary resuscitation and emergency cardiac care technics. Community lives saved yearly were 15.2/100,000 people aged 30 to 69 years and 6.4/100,000 total population. Simultaneously, annual community rates for coronary death as a cause of death and coronary death per 1,000 people fell significantly by 15 and 17 per cent, respectively. Unquantifiable influences included prehospital relief of ischemic chest pain; prehospital correction of acute dysautonomia; prehospital abolition of otherwise prefatal dysrhythmias; similar treatment for acute myocardial infarction in the emergency department, in the inhospital mobile coronary care unit and in the progressive intermediate coronary convalescent unit; and general community education through the media of newspapers, radio and television. The present frequency of coronary death during ambulance transport, 9 to 22 per cent of prehospital coronary deaths in this and other surveys, suggests that the prehospital cardiopulmonary resuscitation and emergency cardiac care component needs improvement in many communities. By reducing prehospital and ambulance coronary death rates, prehospital cardiopulmonary resuscitation and emergency cardiac care for acute myocardial infarction constitutes an essential component of the total system approach to emergency coronary care. Since prehospital cardiopulmonary resuscitation and emergency cardiac care have cheaply and effectively expedited and abbreviated hospitalization for acute myocardial infarction, and lowered community death rates from coronary artery disease, its adoption throughout the United States and the western world seems justified.

Autonomic disturbance at onset of acute myocardial infarction

Of 74 patients seen within 30 minutes of the onset of acute myocardial infarction 68 (92%) had signs of autonomic imbalance. Excessive vagal activity was evident in 41 (55%) and there was sympathetic overactivity in 27 (36%). The high incidence of sudden death in the acute phase of a coronary attack probably results from the electrical imbalance caused by autonomic disturbance. This disturbance must therefore be taken into account in any prophylactic regimen against the lethal early ventricular dysrhythmias.