Low prevalence of abnormal cervical cytology in an institutionalized population with intellectual disability

BACKGROUND

The present study was designed to determine the prevalence of abnormal cervical cytology in an institutionalized population with intellectual disability.

METHOD

A retrospective review of charts for 162 women at a large state-owned facility was performed. Slides from 310 cervical Papanicolau smears were re-screened by a cytotechnologist and then reviewed by a pathologist.

RESULTS

The prevalence of abnormal cytology (three out of 162 participants) and biopsy confirmed that the prevalence cervical dysplasia (one out of 310 smears) was low.

CONCLUSION

The present preliminary study suggests that further investigation of the optimal interval for cervical cancer screening is warranted in this population.

Out-of-hospital cardiac arrest in men and women

BACKGROUND

The incidence of sudden cardiac death is roughly 3 times greater in men than in women. However, in patients treated for out-of-hospital cardiac arrest, the relationships between sex and survival after adjustment for age and cardiac rhythm are unclear.

METHODS AND RESULTS

In this retrospective cohort study, we examined 7069 men and 2582 women who were treated for out-of-hospital cardiac arrest in Seattle and suburban King County between 1990 and 1998. We compared successful prehospital resuscitation (hospital admission) and survival from event to discharge in men and women. Women had markedly reduced rates of ventricular fibrillation (VF), slightly older age, fewer witnessed arrests, and fewer arrests in public locations than men. Although their unadjusted resuscitation rate was lower (29% versus 32%, P<0.0001), women had a greater likelihood of resuscitation than men after adjustment for VF (odds ratio [OR] 1.13; 95% confidence interval [CI], 1.03 to 1.25) and after adjustment for VF plus additional factors (OR, 1.27; 95% CI, 1.14 to 1.41). The difference in resuscitation rates between men and women decreased as they aged (test for trend, P<0.0001). Unadjusted survival rates were also lower in women than in men (11% versus 15%, P<0.0001). Women had similar survival after adjustment for VF (OR, 0.97; 95% CI, 0.85 to 1.11) and after adjustment for VF plus additional factors (OR, 1.09; 95% CI, 0.93 to 1.27).

CONCLUSIONS

The lower unadjusted resuscitation and survival rates observed in women were primarily due to women's lower incidence of VF, a relatively favorable cardiac rhythm. After adjustment for VF and other factors, women had higher resuscitation rates than men, but similar rates of survival from event to discharge.

Dispatcher-assisted cardiopulmonary resuscitation and survival in cardiac arrest

BACKGROUND

Early cardiopulmonary resuscitation (CPR) improves survival in out-of-hospital cardiac arrest, and dispatcher-delivered instruction in CPR can increase the proportion of arrest victims who receive bystander CPR before emergency medical service (EMS) arrival. However, little is known about the survival effectiveness of dispatcher-delivered telephone CPR instruction.

METHODS AND RESULTS

We evaluated a population-based cohort of EMS-attended adult cardiac arrests (n=7265) from 1983 through 2000 in King County, Washington, to assess the association between survival to hospital discharge and 3 distinct CPR groups: no bystander CPR before EMS arrival (no bystander CPR), bystander CPR before EMS arrival requiring dispatcher instruction (dispatcher-assisted bystander CPR), and bystander CPR before EMS arrival not requiring dispatcher instruction (bystander CPR without dispatcher assistance). In this cohort, 44.1% received no bystander CPR before EMS arrival, 25.7% received dispatcher-assisted bystander CPR, and 30.2% received bystander CPR without dispatcher assistance. Overall survival was 15.3%. Using no bystander CPR as the reference group, the multivariate adjusted odds ratio of survival was 1.45 (95% confidence interval [CI], 1.21, 1.73) for dispatcher-assisted bystander CPR and 1.69 (95% CI, 1.42, 2.01) for bystander CPR without dispatcher assistance.

CONCLUSION

Dispatcher-assisted bystander CPR seems to increase survival in cardiac arrest.

Dispatcher assistance and automated external defibrillator performance among elders

OBJECTIVES

Automated external defibrillators (AEDs) provide an opportunity to improve survival in out-of-hospital, ventricular fibrillation (VF) cardiac arrest by enabling laypersons not trained in rhythm recognition to deliver lifesaving therapy. The potential role of emergency dispatchers in the layperson use of AEDs is uncertain. This study was performed to examine whether dispatcher telephone assistance affected AED skill performance during a simulated VF cardiac arrest among a cohort of older adults. The hypothesis was that dispatcher assistance would increase the proportion who were able to correctly deliver a shock, but might require additional time.

METHODS

One hundred fifty community-dwelling persons aged 58-84 years were recruited from eight senior centers in King County, Washington. All participants had received AED training approximately six months previously. For this study, the participants were randomized to AED operation with or without dispatcher assistance during a simulated VF cardiac arrest. The proportions who successfully delivered a shock and the time intervals from collapse to shock were compared between the two groups.

RESULTS

The participants who received dispatcher assistance were more likely to correctly deliver a shock with the AED during the simulated VF cardiac arrest (91% vs 68%, p = 0.001). Among those who were able to deliver a shock, the participants who received dispatcher assistance required a longer time interval from collapse to shock [median (25th, 75th percentile) = 193 seconds (165, 225) for dispatcher assistance, and 148 seconds (138, 166) for no dispatcher assistance, p = 0.001].

CONCLUSIONS

Among older laypersons previously trained in AED operation, dispatcher assistance may increase the proportion who can successfully deliver a shock during a VF cardiac arrest.

Training seniors in the operation of an automated external defibrillator: a randomized trial comparing two training methods

STUDY OBJECTIVE

This study evaluated the differences in efficacy of 2 methods for training seniors in the use of an automated external defibrillator (AED). We tested the hypothesis that each training method (face-to-face instruction compared with video-based instruction) would result in similar AED performance on a manikin.

METHODS

Two hundred ten seniors from various senior centers were randomized to receive face-to-face or video-based instruction on AED skills. Seniors were assessed individually and tested on the speed and quality of AED performance. We retested 177 of these initial trainees 3 months after initial training. Similar performance measures were assessed.

RESULTS

Although there were statistically significant differences between the 2 training methods in terms of average time to shock at both evaluations, the results in general demonstrate that there were no clinically meaningful distinctions (time differences of <20 seconds) between the AED performance of seniors trained with a video and seniors trained in a face-to-face setting at the initial training or at the retention assessment. At the initial evaluation, overall performance was satisfactory, with greater than 98% trained with either method delivering a shock. However, at the 3-month follow-up, almost one fourth of trainees were not able to deliver a shock, and almost half were not able to correctly place the pads on the manikin.

CONCLUSION

We believe that seniors can be trained equally well in AED performance with video-based self-instruction or face-to-face instruction. How to maintain acceptable AED performance skills over time remains a challenge.

Elevated plasma tissue plasminogen activator and anti-THP-1 antibodies are independently associated with decreased graft survival in cardiac transplant recipients

Hemostatic and immunologic factors have been implicated in future cardiac events in patients with coronary artery disease. The role of these factors and their interaction is less established in cardiac transplant recipients. We sought to characterize the role of these factors in these patients. Cardiac transplant patients who presented for surveillance coronary angiography and/or endomyocardial biopsy were eligible for enrollment. Ninety-nine consecutive patients were enrolled. Plasma levels of tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1, von Willebrand factor, fibrin D-dimer, and anti-t-PA antibody were determined by enzyme-linked immunosorbent assays. Anti-THP-1 cell antibodies directed against a monocytic leukemia cell line were detected by incubating patient plasma with THP-1 cells. Bound antibody was detected using goat peroxidase-labeled immunoglobulin G directed against human immunoglobulins. Lipids were measured by enzymatic methods. Multivariate analysis identified the presence of anti-THP-1 cell antibodies (risk ratio 4.41, p = 0.002), t-PA antigen (risk ratio 1.10, p = 0.033), donor age 20 to 26 years (risk ratio 8.83, p = 0.042), and donor age >36 years (risk ratio 15.53, p = 0.009) as predictors of allograft failure. Altered hemostatic function, as demonstrated by elevated plasma t-PA antigen levels, is predictive of subsequent allograft failure in cardiac transplant recipients. In addition, the presence of anti-THP-1 cell antibodies in these patients is predictive of allograft failure.

Barriers and facilitators to the prescription of automated external defibrillators for home use in patients with heart disease: a survey of cardiologists

OBJECTIVE

Because the majority of cardiac arrests occur at home, the use of automated external defibrillators (AEDs) in the home could potentially improve survival of out-of-hospital cardiac arrest. Currently, physicians must prescribe AEDs for home use by patients. The purpose of this study was to investigate the barriers and facilitators to prescription of home use of AEDs.

DESIGN

Telephone interviews were conducted with 85 cardiologists and paper and pencil surveys (via fax) with 59 additional cardiologists in Washington State.

OUTCOME MEASURES

Cardiologists were asked about their current practices and their perceived barriers and facilitators to prescription of AEDs for home use.

RESULTS

Eighty-five percent of the sample believed that AEDs could be effective in preventing death, although only 7% of the cardiologists had ever prescribed an AED. Reasons for nonprescription included the use of implantable cardioverter defibrillators, perceived lack of a clear patient niche, and lack of knowledge about the device. The majority of respondents reported that they would be more likely to prescribe AEDs if they were the standard of care (71%), were covered by insurance (67%), and came with comprehensive training (58%).

CONCLUSION

The results showed that cardiologists believe that home use of AEDs can be effective but that many issues regarding the prescription of AEDs remain.

Out-of-hospital cardiac arrest in octogenarians and nonagenarians

BACKGROUND

Studies of elderly patients who have out-of-hospital cardiac arrest have contradictory results. The studies usually define elderly patients as those older than 70 years, and include relatively few octogenarians and nonagenarians.

OBJECTIVES

To compare the survival after out-of-hospital cardiac arrest of octogenarians, nonagenarians, and younger patients and to determine the influence of age on survival after adjusting for factors known to influence out-of-hospital cardiac arrest outcome.

METHODS

We conducted a retrospective cohort study in suburban King County, Washington, on 5882 patients who had out-of-hospital cardiac arrest from presumed cardiovascular disease between January 1, 1987, and December 31, 1998, and who received cardiopulmonary resuscitation from bystanders, emergency medical technicians, or both. The main outcome measure was survival to hospital discharge.

RESULTS

In patients who had out-of-hospital cardiac arrest due to a cardiac cause, younger patients had higher hospital discharge rates than octogenarians, who in turn had higher hospital discharge rates than nonagenarians (19.4% vs 9.4% vs 4.4%; P<.001). However, survival to hospital discharge improved significantly for younger patients, octogenarians, and nonagenarians who had ventricular fibrillation or pulseless ventricular tachycardia (36% vs 24% vs 17%; P<.001). After multiple logistic regression analysis controlling for other factors, increased age was weakly associated with decreased survival to hospital discharge (odds ratio, 0.92; 95% confidence interval, 0. 85-0.99).

CONCLUSIONS

Octogenarians and nonagenarians have lower survival to hospital discharge than younger patients, but age is a much weaker predictor of survival than other factors such as initial cardiac rhythm. Decisions regarding resuscitation should not be based on age alone. Arch Intern Med. 2000;160:3439-3443.

Elevated levels of plasma C-reactive protein are associated with decreased graft survival in cardiac transplant recipients

BACKGROUND

Inflammation may be involved in the origin of transplant coronary artery disease. We hypothesized that plasma levels of C-reactive protein (CRP) and interleukin-6 (IL-6), markers for systemic inflammation, would correlate with cardiac transplant graft survival.

METHODS AND RESULTS

We studied 99 consecutive cardiac transplant recipients who were referred for routine endomyocardial biopsy and/or surveillance coronary angiography. Plasma levels of CRP and IL-6 were measured by their respective ELISAs. Patients were divided into 2 groups: those who died or required retransplantation and those who survived without the need for retransplantation. During the follow-up period of 5.0+/-2.7 years (range, 0.2 to 15.1 years) after transplant, 20 patients died and 9 required retransplantation. There was no significant difference in age, race, sex, cause of native myopathy, presence of diabetes, or use of aspirin, statins, or calcium channel blockers between the 2 groups. Although IL-6 did not relate to graft failure, CRP level was predictive of allograft failure (P:=0.003). The risk of allograft failure increased 36% for every 2-fold increase in CRP level. Moreover, CRP levels also correlated significantly with the frequency of grade 3 rejection (P:=0.02). In multivariate analysis, when combined with other significant predictors such as donor age and sex mismatching of the graft, CRP still significantly predicted graft failure (P:=0.025) with a 32% increase in the risk of graft failure for every 2-fold increase in CRP level.

CONCLUSIONS

These findings suggest that elevated plasma levels of CRP are associated with subsequent allograft failure in cardiac transplant recipients.

Impact of community intervention to reduce patient delay time on use of reperfusion therapy for acute myocardial infarction: rapid early action for coronary treatment (REACT) trial. REACT Study Group

BACKGROUND

Reperfusion therapy for acute myocardial infarction (AMI) is a time-dependent intervention that can reduce infarct-related morbidity and mortality. Out-of-hospital patient delay from symptom onset until emergency department (ED) presentation may reduce the expected benefit of reperfusion therapy.

OBJECTIVE

To determine the impact of a community educational intervention to reduce patient delay time on the use of reperfusion therapy for AMI.

METHODS

This was a randomized, controlled community-based trial to enhance patient recognition of AMI symptoms and encourage early ED presentation with resultant increased reperfusion therapy rates for AMI. The study took place in 44 hospitals in 20 pair-matched communities in five U.S. geographic regions. Eligible study subjects were non-institutionalized patients without chest injury (aged > or =30 years) who were admitted to participating hospitals and who received a hospital discharge diagnosis of AMI (ICD 410); n = 4,885. For outcome assessment, patients were excluded if they were without survival data (n = 402), enrolled in thrombolytic trials (n = 61), receiving reperfusion therapy >12 hours after ED arrival (n = 628), or missing symptom onset or reperfusion times (n = 781). The applied intervention was an educational program targeting community organizations and the general public, high-risk patients, and health professionals in target communities. The primary outcome was a change in the proportion of AMI patients receiving early reperfusion therapy (i.e., within one hour of ED arrival or within six hours of symptom onset). Trends in reperfusion therapy rates were determined after adjustment for patient demographics, presenting blood pressure, cardiac history, and insurance status. Four-month baseline was compared with the 18-month intervention period.

RESULTS

Of 3,013 selected AMI patients, 40% received reperfusion therapy. Eighteen percent received therapy within one hour of ED arrival (46% of treated patients), and 32% within six hours of symptom onset (80% of treated patients). No significant difference in the trends in reperfusion therapy rates was attributable to the intervention, although increases in early reperfusion therapy rates were noted during the first six months of the intervention. A significant association of early reperfusion therapy use with ambulance use was identified.

CONCLUSIONS

Community-wide educational efforts to enhance patient response to AMI symptoms may not translate into sustained changes in reperfusion practices. However, an increased odds for early reperfusion therapy use during the initiation of the intervention and the association of early therapy with ambulance use suggest that reperfusion therapy rates can be enhanced.

Effect of a community intervention on patient delay and emergency medical service use in acute coronary heart disease: The Rapid Early Action for Coronary Treatment (REACT) Trial

CONTEXT

Delayed access to medical care in patients with acute myocardial infarction (AMI) is common and increases myocardial damage and mortality.

OBJECTIVE

To evaluate a community intervention to reduce patient delay from symptom onset to hospital presentation and increase emergency medical service (EMS) use.

DESIGN AND SETTING

The Rapid Early Action for Coronary Treatment Trial, a randomized trial conducted from 1995 to 1997 in 20 US cities (10 matched pairs; population range, 55,777-238,912) in 10 states.

PARTICIPANTS

A total of 59,944 adults aged 30 years or older presenting to hospital emergency departments (EDs) with chest pain, of whom 20,364 met the primary population criteria of suspected acute coronary heart disease on admission and were discharged with a coronary heart disease-related diagnosis.

INTERVENTION

One city in each pair was randomly assigned to an 18-month intervention that targeted mass media, community organizations, and professional, public, and patient education to increase appropriate patient actions for AMI symptoms (primary population, n=10,563). The other city in each pair was randomly assigned to reference status (primary population, n=9801).

MAIN OUTCOME MEASURES

Time from symptom onset to ED arrival and EMS use, compared between intervention and reference city pairs.

RESULTS

General population surveys provided evidence of increased public awareness and knowledge of program messages. Patient delay from symptom onset to hospital arrival at baseline (median, 140 minutes) was identical in the intervention and reference communities. Delay time decreased in intervention communities by -4.7% per year (95% confidence interval [CI], -8.6% to -0.6%), but the change did not differ significantly from that observed in reference communities (-6. 8% per year; 95% CI, -14.5% to 1.6%; P=.54). EMS use by the primary study population increased significantly in intervention communities compared with reference communities, with a net effect of 20% (95% CI, 7%-34%; P<.005). Total numbers of ED presentations for chest pain and patients with chest pain discharged from the ED, as well as EMS use among patients with chest pain released from the ED, did not change significantly.

CONCLUSIONS

In this study, despite an 18-month intervention, time from symptom onset to hospital arrival for patients with chest pain did not change differentially between groups, although increased appropriate EMS use occurred in intervention communities. New strategies are needed if delay time from symptom onset to hospital presentation is to be decreased further in patients with suspected AMI. JAMA. 2000;284:60-67

Prevalence of aspirin use among patients calling 9-1-1 for chest pain

OBJECTIVE

Early aspirin administration during an acute myocardial infarction (AMI) decreases morbidity and mortality. This investigation examined the extent to which patients with a complaint of chest pain, the symptom most identified with AMI by the general population, self-administer aspirin before the arrival of emergency medical services (EMS) personnel.

METHODS

In this prospective, cross-sectional prevalence study, data were derived through the analysis of EMS incident reports for patients with a complaint of chest pain from June 1, 1997, to August 31, 1997.

RESULTS

The study included 694 subjects. One hundred two (15%) took aspirin for their chest pain before the arrival of EMS personnel. Of the 322 subjects who reported taking aspirin on a regular basis, 82 (26%) took additional aspirin for their acute chest pain. Only 20 (5%) of the 370 patients who were not using regular aspirin therapy self-administered aspirin acutely (p<0.001). In addition, patients with lower intensity of chest pain (p = 0.03) were more likely to take aspirin for their chest pain.

CONCLUSION

Only a relatively small fraction of individuals calling 9-1-1 with acute chest pain take aspirin prior to the arrival of EMS personnel. These individuals are more likely to self-administer aspirin if they are already taking it on a regular basis. It is also possible that they are less likely to take aspirin if their chest pain is more severe.

Rapid early action for coronary treatment: rationale, design, and baseline characteristics. REACT Research Group

OBJECTIVE

Early reperfusion for acute myocardial infarction (AMI) can reduce morbidity and mortality, yet there is often delay in accessing medical care after symptom onset. This report describes the design and baseline characteristics of the Rapid Early Action for Coronary Treatment (REACT) community trial, which is testing community intervention to reduce delay.

METHODS

Twenty U.S. communities were pair-matched and randomly assigned within pairs to intervention or comparison. Four months of baseline data collection was followed by an 18-month intervention of community organization and public, patient, and health professional education. Primary cases were community residents seen in the ED with chest pain, admitted with suspected acute cardiac ischemia, and discharged with a diagnosis related to coronary heart disease. The primary outcome was delay time from symptom onset to ED arrival. Secondary outcomes included delay time in patients with MI/unstable angina, hospital case-fatality rate and length of stay, receipt of reperfusion, and ED/emergency medical services utilization. Impact on public and patient knowledge, attitudes, and intentions was measured by telephone interviews. Characteristics of communities and cases and comparability of paired communities at baseline were assessed.

RESULTS

Baseline cases are 46% female, 14% minorities, and 73% aged > or =55 years, and paired communities have similar demographics characteristics. Median delay time (available for 72% of cases) is 2.3 hours and does not vary between treatment conditions (p > 0.86).

CONCLUSIONS

REACT communities approximate the demographic distribution of the United States and there is baseline comparability between the intervention and comparison groups. The REACT trial will provide valuable information for community educational programs to reduce patient delay for AMI symptoms.

Gender differences in reported symptoms for acute myocardial infarction: impact on prehospital delay time interval

A retrospective observational study using database registry of consecutive patients admitted to 16 King County hospital Coronary Care Units (CCU) was conducted to assess gender differences in symptom presentation for acute myocardial infarction (AMI) and investigate how symptom presentation relates to prehospital delay time interval from acute symptom onset to emergency department (ED) presentation. Between January 1991 and February 1993, 4,497 patients were admitted to the CCUs with diagnosed AMI. Accredited record technicians abstracted age, gender, race, transport method, symptom presentation (chest pain, sweating, nausea, shortness of breath, epigastric pain, and fainting), delay time interval between acute symptom onset and presentation to hospital ED, and discharge diagnosis from the patients' medical records. After adjusting for age and history of diabetes, no gender differences remained for frequencies of chest pain, fainting, or epigastric pain. Women reported more nausea and shortness of breath but less sweating than men as symptoms of AMI. Chest pain, sweating, and fainting were associated with decreasing delay time intervals. Age, gender, histories of AMI and diabetes, and transport choice were also significantly related to delay time interval. These results show that gender differences occur in AMI symptom experience. However, how symptoms relate to the gender gap in delay time interval is not clear. These findings suggest that health care professionals need to tailor information about possible symptoms of AMI to the patient's gender, age, and medical history.

'Call fast, Call 911': a direct mail campaign to reduce patient delay in acute myocardial infarction

OBJECTIVES

A 10-month direct mail campaign was implemented to increase use of emergency medical services via 911 calls and to reduce prehospital delay for individuals experiencing acute myocardial infarction symptoms.

METHODS

This prospective, randomized, controlled trial involved three intervention groups (receiving brochures with informational, emotional, or social messages) and a control group.

RESULTS

Intervention effects were not observed except for individuals who had a history of acute myocardial infarction and who were discharged with a diagnosis of acute myocardial infarction; their 911 use was meaningfully higher in each intervention group than in the control group.

CONCLUSIONS

The mailings affected only the individuals at greatest risk.

Incidence of cardiac arrest during self-transport for chest pain

STUDY OBJECTIVE

To assess the incidence of cardiac arrest among patients who use self-transport to seek medical care for chest pain.

METHODS

This was a retrospective cohort study of patients admitted to a CCU for suspected acute myocardial infarction (AMI) and patients experiencing out-of-hospital cardiac arrest preceded by symptoms in King County, Washington, between January 1, 1992, and July 31, 1994. Participants were identified through use of the databases compiled by the Myocardial infarction Triage and intervention Trial, which reviewed medical records in all area hospitals, and the Cardiac Arrest Surveillance System, which tracks all incidences in which CPR is performed by EMS personnel in King County. Patients whose sudden cardiac arrests were not preceded by symptoms were excluded. Hospital records were abstracted to find the means of transport for patients admitted to CCUs. For cardiac arrest patients, the medical history, presence of symptoms, means of transport, and prehospital death information were abstracted from paramedic field reports. Outcome (admission, discharge, or in-hospital death) was obtained from hospital records. An event cause (cardiac or other) was determined from death certificates, hospital records, or consultation with private physicians.

RESULTS

During the 30-month study period, 13,187 patients sought help for cardiac symptoms and were either admitted to a CCU or died before admission after calling 911. A majority, 7,393 (59%), were transported by emergency medical services, and 5,182 (41%) used private transportation to obtain medical care; the means of transport could not be determined for 612 patients. Of the EMS group, 6,978 were admitted to the hospital without experiencing prehospital cardiac arrest, and 415 (5.6%) arrested before arriving at the hospital. Of the group using private transportation, 5,164 were admitted without arresting and 18 (.35%) arrested before arrival, after which 911 was called (P < .001).

CONCLUSION

The incidence of cardiac arrest among patients who attempted to reach the hospital by private transportation was very low compared with the incidence among those who chose the EMS system for transport. This suggests that patient self-selection occurs, with the more seriously ill patients more commonly calling 911 for transport.

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.

Reasons patients with chest pain delay or do not call 911

STUDY OBJECTIVE

To determine the reasons patients with suspected acute myocardial infarction (AMI) delay seeking medical care or do not call 911.

DESIGN

Telephone interview of patients hospitalized with suspected AMI.

SETTING

Nine hospitals in King County, Washington.

PARTICIPANTS

Patients admitted to a CCU or ICU between October 1, 1986, and December 31, 1987, with suspected AMI occurring out-of-hospital. Spouses of patients who met criteria but died during the hospitalization also participated.

INTERVENTIONS

Hospital records were reviewed, and a 20-minute telephone interview was conducted of patients who reside in King County but do not live in an extended care facility.

MEASUREMENTS

Patient demographics, cardiac history, symptoms, time of acute symptom onset, time of emergency department arrival, method of transportation, discharge diagnosis, and hospital outcome were abstracted from hospital records. Circumstances leading to the hospitalization, reasons for delay in seeking care, and reasons for not calling 911 were determined in the telephone interview.

RESULTS

In a 15-month period, 5,207 patients were hospitalized for suspected AMI in King County, Washington. Twenty-seven percent had AMI. Median patient delay between symptom onset and hospital arrival was 2 hours. Paramedics transported 45% of all patients. A representative subset of patients (2,316) were interviewed. The main reasons for delay were because the patient thought that the symptoms would go away, because the symptoms were not severe enough, and because the patient thought that the symptoms were caused by another illness. The main reasons for not calling 911 were because the symptoms were not severe enough, because the patient did not think of calling 911, and because the patient thought that self-transport would be faster because of his or her close location to the hospital.

CONCLUSION

Maximal benefit from thrombolytic therapy is not realized in a substantial proportion of patients with AMI because of delays in seeking medical care. Knowledge of the reasons patients delay or do not call 911 can help focus efforts on achieving more rapid treatment of patients with AMI.

Utilization of emergency medical services for symptoms of acute myocardial infarction

OBJECTIVE

To examine patient characteristics and situational and clinical factors that affect utilization of Emergency Medical Services (EMS) for symptoms of acute myocardial infarction (AMI).

DESIGN

Telephone interview of patients hospitalized with suspected AMI.

SETTING

Nine hospitals in King County, Washington.

PATIENTS

Patients admitted to a coronary or intensive care unit between October 1, 1986, and December 31, 1987, with suspected AMI occurring out of hospital. Spouses of patients who met criteria but died during the hospitalization also participated.

OUTCOME MEASURES

Patient demographics, coping strategies, situational factors, prior cardiac history, perceived symptom severity, belief about the nature of condition, and method of transportation.

RESULTS

Descriptive statistics showed that although few patients called EMS as a "first thing" in response to symptoms, almost half of all patients called EMS before being hospitalized. Stepwise logistic regression analyses revealed that being older, the belief that one was experiencing a heart attack, the presence of other people (including the spouse), and the lack of physical activity at time of symptom onset, were related to both greater and quicker utilization of EMS. Additionally, education, medical history of angina, and severity of symptoms also were related to utilization of EMS.

CONCLUSION

The findings are discussed in a theoretical context, using Leventhal's self-regulatory model to suggest avenues for future research and interventions.

Impact of direct mail intervention on knowledge, attitudes, and behavioral intentions regarding use of emergency medical services for symptoms of acute myocardial infarction

This study evaluated a direct mail intervention called the "Call Fast, Call 911" campaign designed to increase use of emergency medical services for symptoms of acute myocardial infarction. The campaign was targeted at individuals over the age of 50. Persons over 50 years of age (N = 130,000) in King County, Washington, were randomly assigned to intervention or control groups. Individuals in the intervention groups received six direct mail pieces over a 1-year period encouraging them to call 911 quickly in response to chest pain. A postintervention telephone survey of a random sample of households (N = 434) assessed the impact of the campaign on knowledge, attitudes, and behavioral intentions regarding use of emergency medical services for symptoms of acute myocardial infarction. The results showed no significant differences between intervention and control groups in terms of knowledge of AMI. However, there were significant differences in beliefs and behavioral intentions to call 911 in a cardiac emergency.

Increasing the efficiency of emergency medical services by using criteria based dispatch

STUDY OBJECTIVES

To determine whether criteria based dispatch (CBD) improved the efficiency of the emergency medical services system.

DESIGN

A before and after design was used to measure effects of CBD. Data were reviewed from medical reports from January 1986 through June 1992.

SETTING

King County, Washington, excluding the city of Seattle.

PARTICIPANTS

Residents who called 911 to report a medical emergency.

INTERVENTIONS

Emergency medical dispatching (EMD), basic life support (BLS), and advanced life support (ALS).

RESULTS

Findings show a decrease in ALS responses for two tracer conditions that medical control physicians determined not require ALS intervention. The percentage of febrile seizures in which paramedics responded decreased from 41% to 21% (P < .001). The percentage of cerebrovascular accidents in which paramedics responded decreased from 41% to 28% (P < .001). CBD led to a decrease, from 4.7% to 3.8% (P < .001), in frequency of requests by BLS units for dispatch of ALS units. There was no increase in the time required to dispatch each call.

CONCLUSION

CBD increased the efficiency of the EMS system by significantly reducing ALS responses to incidents not requiring ALS intervention and reducing requests by BLS units for dispatch of ALS units while maintaining a consistent time from receipt of call to dispatch.

911 and emergency department use for chest pain: results of a media campaign

STUDY OBJECTIVE

We evaluated the effects of a community public education campaign that encouraged patients to quickly call 911 after the onset of acute myocardial infarction (AMI) symptoms.

SETTING AND PARTICIPANTS

The media campaign focused on residents 50 years of age or older in King County, Washington, which has a population of 1.5 million (1990 census).

DESIGN

We determined 911 responses for chest pain, emergency department visits for AMI symptoms, the number of patients admitted to a CCU with an admitting diagnosis of rule-out MI, and the number of confirmed AMIs before and after the campaign.

RESULTS

The number of emergency medical services (EMS) responses (911 runs) for patients 50 years of age or older experiencing AMI symptoms increased significantly during the media campaign. ED visits for chest pain also increased significantly during the campaign, as did the number of patients 50 years of age or older admitted to a King County CCU with an admitting diagnosis of rule-out MI. Each of the above increases tapered--with time after the media campaign but remained above baseline.

CONCLUSION

An intense public education campaign can significantly increase EMS use, ED visits, and CCU admissions for AMI symptoms. However, these effects taper off with time after the campaign.

Predicting survival from out-of-hospital cardiac arrest: a graphic model

STUDY OBJECTIVE

To develop a graphic model that describes survival from sudden out-of-hospital cardiac arrest as a function of time intervals to critical prehospital interventions.

PARTICIPANTS

From a cardiac arrest surveillance system in place since 1976 in King County, Washington, we selected 1,667 cardiac arrest patients with a high likelihood of survival: they had underlying heart disease, were in ventricular fibrillation, and had arrested before arrival of emergency medical services (EMS) personnel.

METHODS

For each patient, we obtained the time intervals from collapse to CPR, to first defibrillatory shock, and to initiation of advanced cardiac life support (ACLS).

RESULTS

A multiple linear regression model fitting the data gave the following equation: survival rate = 67%-2.3% per minute to CPR-1.1% per minute to defibrillation-2.1% per minute to ACLS, which was significant at P < .001. The first term, 67%, represents the survival rate if all three interventions were to occur immediately on collapse. Without treatment (CPR, defibrillatory shock, or definitive care), the decline in survival rate is the sum of the three coefficients, or 5.5% per minute. Survival rates predicted by the model for given EMS response times approximated published observed rates for EMS systems in which paramedics respond with or without emergency medical technicians.

CONCLUSION

The model is useful in planning community EMS programs, comparing EMS systems, and showing how different arrival times within a system affect survival rate.

Hospital mortality in acute myocardial infarction in the era of reperfusion therapy (the Myocardial Infarction Triage and Intervention Project)

This study was conducted in 19 hospitals in the metropolitan Seattle area and included 6,270 unselected patients who had acute myocardial infarction (AMI) between January 1988 and April 1991. Hospital mortality was determined and related to patient demographic and clinical characteristics, the use of reperfusion therapies, and to complications after AMI. Thrombolytic therapy or direct coronary angioplasty < 6 hours from symptom onset was used to treat 1,185 (19%) and 524 (9%) patients, respectively. There were 629 (10%) hospital deaths; most occurred during the first 3 days of hospitalization. Factors affecting mortality after admission included: recurrent chest pain, recurrent AMI, development of heart failure, and the occurrence of stroke. After adjustment for age, treatment with thrombolytic therapy or direct angioplasty had no independent effect on reducing the overall mortality rate. Hospital mortality rates for AMI have improved considerably since 1970, although recurrent myocardial ischemic events continue to have an adverse effect on outcome. The current use of reperfusion treatments has had minimal causal impact on overall mortality rates, principally because less than one third of patients, who are relatively "low risk," are eligible and receive these treatments.

Prehospital delay interval for patients who use emergency medical services: the effect of heart-related medical conditions and demographic variables

STUDY OBJECTIVE

To investigate the effect of heart-related medical conditions and demographic variables on patients' tendency to delay contacting emergency medical services for symptoms of acute myocardial infarction.

TYPE OF PARTICIPANTS

A sample of 2,947 patients with acute myocardial infarction but no cardiac arrest, transported by paramedics to the coronary care units of 19 hospitals in King County, Washington, between January 1988 and April 1991.

MEASUREMENTS

Patient record abstracts contained information on medical history, age, gender, delay interval, and means of transportation.

RESULTS

Multiple regression analyses showed that prehospital delay interval was significantly greater for individuals who were older and female and who had a history of angina, congestive heart failure, or diabetes.

CONCLUSION

It is important to investigate further how people interpret and evaluate their symptoms in light of other medical conditions. It is also critical to find out why women delay longer than men and why older individuals delay longer than younger people before they contact emergency medical services. Interventions need to be developed that are targeted at populations at risk for delaying use of emergency medical services for acute myocardial infarction symptoms. These interventions must legitimize the use of emergency medical services and encourage patients to act quickly when confronted with acute myocardial infarction symptoms.

The association between on-site cardiac catheterization facilities and the use of coronary angiography after acute myocardial infarction. Myocardial Infarction Triage and Intervention Project Investigators

BACKGROUND

During the past decade the use of coronary angiography after acute myocardial infarction has substantially increased. Among the possible contributing factors, the increasing availability of cardiac catheterization facilities was the focus of our investigation.

METHODS

We investigated whether the availability of cardiac catheterization facilities at an admitting hospital was associated with the likelihood that a patient would undergo coronary angiography. After adjusting for age, sex, cardiac history, and cardiac complications during hospitalization, we evaluated this association in 5867 consecutive patients with acute myocardial infarction admitted to 19 Seattle-area hospitals. We also assessed the association between the presence of on-site cardiac catheterization facilities and in-hospital mortality.

RESULTS

Patients admitted to hospitals with on-site cardiac catheterization facilities were far more likely to undergo coronary angiography (odds ratio, 3.21; 95 percent confidence interval, 2.81 to 3.67) than patients admitted to hospitals where transfer to another institution would be required to perform cardiac catheterization. Admission to a hospital with on-site facilities was more strongly associated with the use of coronary angiography than any characteristic of the patient. Although our study had limited power to detect differences in mortality, the availability of coronary angiography had no discernible association with in-hospital mortality rates (odds ratio for mortality among patients admitted to hospitals with on-site facilities vs. patients admitted to hospitals without such facilities, 0.88; 95 percent confidence interval, 0.71 to 1.09).

CONCLUSIONS

In this community-wide study, the availability of on-site cardiac catheterization facilities was associated with a higher likelihood that a patient would undergo coronary angiography. However, admission to hospitals with these facilities did not appear to be associated with lower short-term mortality.

Thrombolytic therapy

All patients with symptoms and ECG findings suggestive of acute myocardial infarction (AMI) should be considered for treatment with thrombolytic agents. The decision to use thrombolytic therapy is a clinical judgment based upon a weighing of the potential benefits versus the possible risks. The physician must take into account relative contraindications, age of the patient, area of jeopardized myocardium, and duration of symptoms. Health professionals involved in the care of AMI patients should develop written plans and protocols addressing the following matters: identification of patients with chest pain in the prehospital setting (this applies to hospitals that receive patients from emergency medical services systems), triage of patients in the emergency department, obtaining the 12-lead electrocardiogram, determination of contraindications, authority for ordering thrombolytic therapy, and consultation for atypical cases. There also should be agreed standards for the time interval from arrival in the ED to administration of the thrombolytic agent, as well as a commitment to the prospective monitoring of procedures and times to assure continuous improvement. A time interval for treatment (arrival in ED to administration of drug) of 30 to 60 minutes should be achievable for patients who present with typical symptoms and ECG findings.

Incidence of agonal respirations in sudden cardiac arrest

STUDY OBJECTIVE

To discover the frequency of agonal respirations in cardiac arrest calls, the ways callers describe them, and discharge rates associated with agonal respirations.

DESIGN

We reviewed taped recordings of calls reporting cardiac arrests and emergency medical technician and paramedic incident reports for 1991. Arrests after arrival of emergency medical services were excluded.

SETTING

King County, Washington, excluding the city of Seattle.

PARTICIPANTS

Four hundred forty-five persons with out-of-hospital cardiac arrests receiving emergency medical services.

INTERVENTIONS

Telephone CPR, emergency medical technicians-defibrillation, and advanced life support by paramedics.

MEASUREMENTS AND MAIN RESULTS

Any attempts at breathing described by callers were identified, as well as whether agonal respirations could be heard by dispatcher, emergency medical technicians, or paramedics. Agonal respirations occurred in 40% of 445 out-of-hospital cardiac arrests. Callers described agonal breathing in a variety of ways. Agonal respirations were present in 46% of arrests caused by cardiac etiology compared with 32% in other etiologies (P < .01). Fifty-five percent of witnessed arrests had agonal activity compared with 16% of unwitnessed arrests (P < .001). Agonal respirations occurred in 56% of arrests with a rhythm of ventricular fibrillation compared with 34% of cases with a nonventricular fibrillation rhythm (P < .001). Twenty-seven percent of patients with agonal respirations were discharged alive compared with 9% without them (P < .001).

CONCLUSION

There is a high incidence of agonal activity associated with out-of-hospital cardiac arrest. Presence of agonal respirations is associated with increased survival. These findings have implications for public CPR training programs and emergency dispatcher telephone CPR programs.

The epidemiology of cardiac arrest in young adults

STUDY OBJECTIVE

To describe the epidemiology of cardiac arrest in young adults and to determine if there are characteristics unique to this group in terms of etiology, rhythm, and outcome.

DESIGN

Retrospective, case review.

SETTING

King County, Washington.

TYPE OF PARTICIPANTS

All out-of-hospital victims of cardiac arrest who received emergency aid.

MEASUREMENTS

The etiology, cardiac rhythm, and outcome were identified for each case.

MAIN RESULTS

During the 13-year period from 1976 to 1989, there were 8,054 cardiac arrests; 252 of these were among young adults 18 to 35 years of age. Of those 252 cases, 61 (24%) were caused by ischemic heart disease, and 60 (24%) were caused by overdose. Asystole was the most common rhythm (48%), followed by ventricular fibrillation or tachycardia (31%). Long-term survival following these rhythms was 4% and 28%, respectively. In terms of age, etiology, and rhythm, young adults appear to represent a transitional group between children and older adults. There were no unique characteristics specific to young adults. Long-term survival is dependent more on rhythm than on age.

CONCLUSION

In terms of age, etiology, and rhythm, young adults appear to represent a transitional group between children and older adults.

Multiple-dose sodium polystyrene sulfonate in lithium intoxication: an animal model

Previous work in our laboratory has demonstrated that sodium polystyrene sulfonate (SPS) significantly lowered serum lithium (Li) concentrations when administered in a single oral dose after an oral dose of lithium in a mouse model. The present study was designed to determine whether: 1) repetitive doses of SPS are effective in lowering serum lithium concentrations, 2) the effect of SPS on lithium concentration is dose related and 3) SPS enhances the elimination of lithium. Mice (N = 144) were given orogastric LiCl (250 mg/kg) and then divided into 4 groups: Controls received water 0, 30, 90, 180, and 360 min. after LiCl; the Full-Dose SPS Group received SPS (5 g/kg/dose) at equivalent times; the Half-Dose SPS Group received SPS (2.5 g/kg/dose) at the same times; and the Elimination Group received water at 0 and 30 min. after LiCl and SPS at 90, 180 and 360 min. after LiCl. Subgroups of each group were sacrificed at 1, 2, 4 and 8 hr post-treatment and serum analyzed for lithium concentrations. Statistical analyses revealed that, when compared to Controls: 1) SPS significantly lowered serum lithium concentrations; 2) this effect was dose-related; 3) repetitive dosing of SPS appears to enhance the elimination of lithium.

Numerators, denominators, and survival rates: reporting survival from out-of-hospital cardiac arrest

This study demonstrates the effect of different denominators on the survival rate from out-of-hospital cardiac arrest. We retrospectively analyzed data from a cardiac arrest surveillance system in King County, Washington during the years 1976 to 1988, and calculated survival rates using eight different definitions of denominators. The eight survival rates ranged from 16% to 49% discharge from hospital. The denominator for the lowest survival rate included all cases of cardiac arrest for whom emergency medical services personnel started cardiopulmonary resuscitation. The denominator for the highest survival rate included: all cases of presumed cardiac etiology; first recorded rhythm was ventricular fibrillation; collapse witnessed; cardiopulmonary resuscitation started by bystanders within 4 minutes; and definitive care provided within 8 minutes. The definition of cases included in the denominator can dramatically effect the resultant survival rate. There must be national and international agreement about definitions of denominators for valid cross community comparisons.

Effect of age on use of thrombolytic therapy and mortality in acute myocardial infarction. The MITI Project Group

The findings in 3,256 consecutive patients hospitalized for acute myocardial infarction were tabulated to assess the history, treatments and outcome in the elderly; 1,848 patients (56%) were greater than 65 years of age, including 28% who were aged greater than or equal to 75 years. The incidence of prior angina, hypertension and heart failure (only 3% of patients less than 55 years of age had a history of heart failure compared with 24% greater than or equal to 75 years old) was found to increase with age. Twenty-nine percent of patients less than 75 years of age were treated with a systemic thrombolytic drug compared with only 5% of patients older than 75 years. Mortality rates increased strikingly with advanced age (less than 2% in patients less than or equal to 55, 4.6% in those 55 to 64, 12.3% in those 65 to 74 and 17.8% in those greater than or equal to 75 years). Both the incidence of complicating illness and a nondiagnostic electrocardiogram (ECG) increased with age. In a multivariate analysis of outcome in older patients (greater than or equal to 65 years), adverse events were related to both prior history of heart failure (odds ratio 3.9) and increasing age (odds ratio 1.4 per each decade of age). Outcome was not improved by treatment with thrombolytic drugs, but these agents were prescribed to only 12% of patients greater than 65 years of age, thereby reducing the power for detecting such an effect.(ABSTRACT TRUNCATED AT 250 WORDS)