Biomedical subjects
Publications and source records attributed to Roger D White.
In this study of a unique cohort of out-of-hospital cardiac arrest survivors with ventricular fibrillation, the initial ejection fraction was predictive of increased long-term mortality. However, overall long-term quality-of-life was favorable and independent of the ejection fraction.
BACKGROUND: Survival following out-of-hospital cardiac arrest (OHCA) from ventricular fibrillation (VF) is poor and dependent on a rapid emergency response system. Improvements in emergent early response have resulted in a higher percentage of patients surviving to admission. However, the admission variables that predict both short- and long-term survival in a region with high discharge survival following OHCA require further study in order to identify survivors at subsequent highest risk. METHODS: All patients with OHCA arrest in Olmsted County Minnesota between 1990 and 2000 who received defibrillation of VF by emergency services were included in the population-based study. Baseline patient admission characteristics in survivor and nonsurvivor groups were compared. Survivors to hospital discharge were prospectively followed to determine long-term survival. RESULTS: Two hundred patients suffered a VF arrest. Of these patients, 145 (73%) survived to hospital admission (7 died within the emergency department) and 79 (40%) were subsequently discharged. Sixty-six (83%) were male, with an average age of 61.9 +/- 15.9 years. Univariate predictors of in-hospital mortality included call-to-shock time (6.6 vs. 5.5 min, p = 0.002), a nonwitnessed arrest (75.4 vs. 92.4%, p = 0.008), in-field use of epinephrine (27.8 vs. 93.4%, p < 0.001), age (68.1 vs. 61.9 years, p = 0.017), hypertension (36.1 vs. 14.1%, p = 0.005), ejection fraction (32.4 vs. 42.4, p = 0.012), and use of digoxin (34.9 vs. 12.7%, p = 0.002). Of all these variables, hypertension [hazard ratio (HR) 4.0, 95% CI 1.1-14.1, p = 0.03], digoxin use (HR 4.5, 95% CI 1.3-15.6, p = 0.02), and epinephrine requirement (HR 62.0, 95% CI 15.1-254.8, p < 0.001) were multivariate predictors of in-hospital mortality. Nineteen patients (24%) had died prior to the survey follow-up. Five patients experienced a cardiac death, resulting in a 5-year expected cardiac survival of 92%. Multivariate variables predictive of long-term mortality include digoxin use (HR 3.02, 95% CI 1.80-5.06, p < 0.001), hypertension (HR 2.06, 95% CI 2.12-3.45, p = 0.006), and call-to-shock time (HR 1.18, 95% CI 1.01-1.38, p = 0.038). CONCLUSION: A combined police/fire/EMS defibrillation program has resulted in an increase of patients surviving to hospital admission after OHCA. This study confirms the need to decrease call-to-shock times, which influence both in-hospital and long-term mortality. This study also identifies the novel demographic variables of digoxin and hypertension, which were also independent risk factors of increased in-hospital and long-term mortality. Identification of these variables may provide utility in identifying those at high-risk of subsequent mortality after resuscitation.
OBJECTIVES: The aims of this study were to describe the trends of ventricular fibrillation (VF) out-of-hospital cardiac arrest in Rochester, Minnesota, since 1985 and to determine coexistent trends in implantable cardioverter defibrillator (ICD) placement and termination of potentially lethal ventricular arrhythmias that might explain, at least in part, a declining incidence trend. BACKGROUND: The incidence of VF out-of-hospital cardiac arrest treated by emergency medical services (EMS) personnel has declined over the past decade. Because VF out-of-hospital cardiac arrest occurs primarily in the setting of severe coronary artery disease, primary and secondary prevention strategies may account in part for the decline. In particular, ICD use in large primary and secondary prevention clinical trials in patients at high risk of sudden death has demonstrated that these devices improve survival. METHODS: All residents of the City of Rochester, Minnesota, who presented with a VF out-of-hospital cardiac arrest from 1985 to 2002, identified and treated by EMS, were included in the study. In addition, residents of the City of Rochester who received their first ICD implant from 1989 to 2002 were identified. From the ICD records, general demographics, etiology of heart disease, comorbid medical disease, and indication for ICD placement were abstracted. Follow-up data obtained from this population included ICD shocks, the underlying rhythm disturbance, and death. RESULTS: The overall incidence of EMS-treated VF out-of-hospital cardiac arrest in Rochester during the study period was 17.1 per 100,000 [95% confidence interval (CI) 15.1-19.4]. The incidence has decreased significantly (P < 0.001) over the study period: 1985-1989: 26.3/100,000 (95% CI 21.0-32.6), 1990-1994: 18.2/100,000 (95% CI 14.1-23.1), 1995-1999: 13.8/100,000 (95% CI 10.4-17.9), 2000-2002: 7.7/100,000 (95% CI 4.7-11.9). One hundred ten patients received an ICD. The placement of ICDs also has increased dramatically over the past 10 years: 1990-1994: 5.0/100,000 to 2000-2002: 20.7/100,000 (P < 0.001). ICDs terminated VF or fast ventricular tachycardia (<270 ms) in 22 patients. Termination of these potentially fatal arrhythmias has shown a trend toward an increase over the study period: 1990-1994: 1.1/100,000 to 2000-2002: 3.5/100,000 (P = 0.06). CONCLUSIONS: The incidence of VF out-of-hospital cardiac arrest is declining. In contrast, the rates of ICD placement and ICD termination of ventricular tachycardia or VF are markedly increasing. Sudden death preventive strategies are multifactorial. These observations suggest that ICD termination of potentially lethal ventricular arrhythmias may contribute to the lower incidence of VF out-of-hospital cardiac arrest.
Primary systemic amyloidosis (AL) is a well-recognized systemic disease, and cardiac amyloidosis accounts for 10% of all nonischemic cardiomyopathies [J S C Med Assoc 97 (2001) 201-206]. The median survival of patients with symptomatic congestive heart failure secondary to cardiac amyloidosis is 4 months [New Engl J Med 336 (1997) 1202-1207; Am J Med 100 (1996) 290-298]. The cause of death in most patients is refractory congestive heart failure or sudden arrhythmic [Mayo Clin Proc 59 (1984) 589-597]. While there are reports of in-hospital arrhythmic deaths in these patients, there are no detailed reports that describe the presentation and management of patients with cardiac amyloidosis who have experienced an out-of-hospital cardiac arrest (OHCA). We describe here our experience with four patients with AL who had an OHCA, including presenting rhythms, interventions, and outcomes.
BACKGROUND: Brain injury after a cardiac arrest remains a major cause of morbidity. Programs focusing on early defibrillation have yielded improved survival of patients after hospital discharge following ventricular fibrillation (VF) out-of-hospital cardiac arrest (OHCA). Early defibrillation that promptly restores a circulating rhythm should decrease the hypoxic period and subsequent organ injury. Therefore this study was designed to determine if long-term memory complaints persist in VF OHCA survivors resuscitated in an early defibrillation program when compared with a healthy control population not experiencing cardiac arrest. METHODS: All patients with an OHCA between November 1990 and January 2001 who received defibrillation by emergency medical services personnel in Olmsted County, MN, USA, were included. The memory function questionnaire (MFQ), a 64-item, 7-point Likert-scaled instrument to evaluate the perception of everyday memory functioning was sent to all survivors. The MFQ comprises four scales: general frequency of forgetting (rates general forgetting), retrospective functioning (compares current memory with past ability), seriousness of forgetting (rates how memory impairment impacts daily life), and mnemonics usage (measures adaptation). The MFQ is scaled so that high scores reflect less severe memory complaints. The comparison population comprised members of the Mayo Older Americans Normative Studies (MOANS) cohort. Quality of life was ascertained with a short form (SF)-36 survey. RESULTS: Seventy-nine of the 200 VF OHCA patients (40%) were discharged. Twenty-two patients have died since dismissal, with an overall average length of follow-up of 4.9+/-3.0 years. Thirty-eight (67%) of the survivors completed the MFQ. Compared with the normal, there was a significant decrease in the general frequency of forgetting score of 144.2+/-37.4 versus 168.1+/-27.3 ( P<0.001) and the seriousness of forgetting score of 84.8 +/-26.7 versus 95.2+/-19.7 (P=0.004). The retrospective function-scale scores were not significantly different ( 18.4+/-6.8 versus 18.7+/- 5.0 (P=0.74). Younger patients (lesser than 65 years of age) reported an increase in general forgetting and the seriousness of forgetting compared with older survivors. A comparison with SF-36 scores suggested an association between general forgetting and decreased vitality (P=0.03) and the seriousness of forgetting with a decreased general health (P=0.005), mental health (P=0.009), physical functioning ( P=0.02 ), and vitality ( P=0.05). CONCLUSION: In a cohort of VF OHCA patients, survivors report more memory complaints in comparison with a general healthy older population. There were more long-term-memory complaints in younger patients. Patients with higher long-term quality-of-life score have fewer memory complaints.
BACKGROUND: The potential impact of efforts to improve the chain of survival for out-of-hospital sudden cardiac arrest (SCA) is unclear in part because estimates of the incidence of treatable cases of SCA are uncertain. The aim of the investigation was to determine a representative national incidence of emergency medical services (EMS)-treated all-rhythm and ventricular fibrillation (VF) SCA as well as survival. METHODS: We used Medline to identify peer-reviewed articles published between 1 January 1980 and 31 March 2003 that reported a US community's EMS SCA experience. Inclusion criteria required the study to include at least 25 cases, report the total number of all-rhythm and/or ventricular fibrillation arrests, and provide information about population size and study duration. Incidence was computed by dividing the total number of SCA events by the product of the community's population and the study duration. RESULTS: Reports from 35 communities met the inclusion criteria. A total of 35,801 all-rhythm EMS-treated cardiac arrests occurred during 62.11 million person-years of observation resulting in an overall incidence of 54.99 per 100,000 person-years. The incidence of ventricular fibrillation-rhythm SCA was 21.32 per 100,000 person-years. Sensitivity analyses generally produced similar results. Applying these results to the US population, 155,000 persons would experience EMS-treated all-rhythm SCA and 60,000 persons would experience EMS-treated ventricular fibrillation-rhythm SCA annually in the US. Survival was 8.4% for all-rhythm and 17.7% for ventricular fibrillation SCA. CONCLUSION: The results provide a framework to assess opportunities and limitations of EMS care with regard to the public health burden of SCA.
BACKGROUND: Programs focusing on early defibrillation have improved both short- and long-term survival of patients with VF out-of-hospital cardiac arrest (OHCA). Subsequent long-term management of survivors would be facilitated by a straight-forward, non-invasive method of identifying those at highest risk for recurrence. Therefore, we assessed the predictive value of the standard ECG to determine both short- and long-term outcomes in survivors of VF OHCA to assist in risk stratification of those patients at highest risk of sudden death. METHODS: All patients with an OHCA between November 1990 and December 2000 who received early defibrillation for VF in Olmsted County Minnesota (MN) were included. Cox proportional hazards modeling was used to examine ECG variables and subsequent ICD deployment and death. RESULTS: Two hundred patients presented in VF OHCA; of these 138 (69%) survived to hospital admission (seven died in the emergency department prior to admission) and 79 (40%) were discharged. The QRS duration (141 +/- 41ms in nonsurvivors, 123 +/- 35 in survivors, P = 0.004) was predictive of short-term mortality in patients who did not survive to hospital discharge. The ventricular rate, PR interval, presence of right or left bundle branch block, QTc, ST elevation myocardial infarction, and atrial fibrillation/flutter were nonpredictive. The average length of follow up for hospital dismissal survivors was 4.8 +/- 3.0 years. In univariate analysis, each 30 ms interval increase in the QRS width and PR interval was associated with increased mortality and ICD deployment hazard ratio of 1.6 (CI 1.1-2.5, P = 0.02) and 1.12 (CI 1.0-1.2, P = 0.05), respectively. In multivariate analysis accounting for admission ejection fraction, a PR > 200 ms [HR 4.5 (CI 1.7-11.8, P = 0.022)], QRS width increase greater than 30 ms [HR 1.9 (CI 1.3-2.8, P < 0.001)], and a QRS > 120 ms [HR 2.4 (CI 1.1-5.4, P = 0.032)] were predictive of long-term mortality and ICD shocks. CONCLUSION: Careful evaluation of the admitting and discharge ECG provides prognostic information for in-hospital and long-term outcomes, respectively in this cohort of out-of-hospital cardiac arrest survivors. The QRS duration on the dismissal ECG following VF OHCA provides prognostic information which might be useful to identify those at highest risk long-term, and who would benefit from more aggressive antiarrhythmic therapy and cardiac stabilization.
OBJECTIVE: Early defibrillation programs have improved long-term outcomes following out-of-hospital cardiac arrest from ventricular fibrillation. Although long-term collective quality of life and survival are favorable, there are subsets of these patients who may be predisposed to worse outcomes. In particular, elderly patients may present with more comorbid medical conditions affecting their outcome. However, the impact of age on mortality rate and quality of life after rapid defibrillation is unknown. DESIGN: Observational study. SETTING: Hospital. SUBJECTS: All patients with an out-of-hospital cardiac arrest between November 1990 and January 2001 who received rapid defibrillation for ventricular fibrillation in Olmsted County, Minnesota. All patients received treatment at one hospital. INTERVENTIONS: Long-term outcome and quality of life were followed. Survival was estimated using the Kaplan-Meier method. The quality of life was established by an SF-36 survey. MEASUREMENTS AND MAIN RESULTS: Two hundred patients presented in ventricular fibrillation out-of-hospital cardiac arrest; of these, 138 (69%) survived to hospital admission, seven (4%) died in the emergency department, and 79 (39%) were discharged neurologically intact. The average age was 62+/-16 yrs, with 51% (n = 40) of the population > or =65. The average length of follow-up was 4.8+/-3.0 yrs. The 5-yr survival in patients <65 was 94% (confidence interval, 86-100%) and 66% (confidence interval, 52-84%) in patients > or =65 (p <.001). The observed survival in the younger group was not different from that expected in a U.S. age- and gender-matched population. However, in the older group, the expected survival was significantly lower compared with an age- and gender-matched U.S. population (p =.01) but similar to an age-, gender-, and disease-matched cohort of patients from Olmsted County not experiencing an arrest. In both age-dependent cohort populations, the quality of life scores crossed the norm in all categories with exception of vitality in patients >65 yrs old (42.6+/-7.2). In direct comparison between the two patient groups, the older cohort reported lower levels of physical functioning (p =.002), role-emotional score (p =.03), and role-physical score (p =.007). Other SF-36 scores were not different between the groups. Sixty-five percent of patients <65 yrs returned to work compared with 56% of older patients. CONCLUSIONS: The survival rate for ventricular fibrillation out-of-hospital cardiac arrest is significantly improved by the presence of a rapid defibrillation program. In patients <65 yrs old, long-term survival is equal to that of normal individuals and quality of life is similar to the general population. The survival, although high, in older patients is less than that in age-matched healthy controls, and physical and emotional quality of life scores are decreased.
OBJECTIVE: To determine the prevalence and frequency of recurrent ventricular fibrillation (VF) in patients defibrillated by police and firefighters only and to determine its relation to survival. DESIGN: Retrospective observational study. SETTING: Out of hospital. PATIENTS: Individuals with witnessed VF arrest in the Rochester, MN, ambulance public service area who had defibrillatory shocks delivered by police and firefighters and return of spontaneous circulation with shocks only. MEASUREMENTS AND MAIN RESULTS: Electrocardiograms were recovered from data cards in automated external defibrillators used by police (n = 49) or firefighters (n = 18) to deliver shocks from December 1996 through December 2003 in the Rochester, MN, ambulance public service area. Patients with witnessed VF arrest were identified for recurrent VF after initial shock success (first one to three shocks). Both police and firefighters deployed automated external defibrillators delivering nonescalating 150-J biphasic truncated exponential waveform shocks (ForeRunner Automated External Defibrillator, Phillips/Heartstream Operation, Seattle, WA). Among 67 patients, 30 (45%) survived to neurologically intact discharge (overall performance category score of 1 in 29 patients and score of 2 in one patient). Twenty-nine patients (43%) regained spontaneous circulation with shocks only and 25 of 29 (86%) survived. VF recurred in 35 of the 67 patients (52%) while being cared for by police or firefighters. Of these 35 patients, no relation was found between the prevalence or frequency of VF recurrence and survival. CONCLUSIONS: VF recurrence is frequent, variable in time of onset, and unrelated to the performance of bystander CPR. The prevalence and frequency of VF recurrence were unpredictable and do not adversely affect survival. Thus, vigilance for recurrent VF is essential to ensure the survival of patients who are in the care of first responders, even after initial restoration of pulses with shocks.
BACKGROUND: This is a study of the influence of body weight on defibrillation, resuscitation, and survival in patients with out-of-hospital cardiac arrest treated with a nonescalating impedance-compensating 150-J biphasic waveform defibrillator. METHODS: Cardiac arrest data from Rochester, MN, emergency medical services over a 6-yr period was retrospectively analyzed. Patient weight data were available for 62 of the 68 patients who were treated initially by basic life support personnel and who presented with a shockable rhythm. For each defibrillation and resuscitation outcome variable, we tested for differences in body weight for successful vs. unsuccessful outcome. RESULTS: Initial shocks defibrillated 92% (83% to 97%) of patients. Cumulative success with two shocks was 98% (confidence interval, 92% to 100%) and with three shocks was 100% (confidence interval, 95% to 100%). The mean shock impedance was 90 +/- 21 ohms. The average body weight was 84 +/- 17 kg (minimum, 53 kg; maximum, 135 kg) and was normally distributed. Based on the body mass index for 46 patients, approximately 41% were classified as overweight (body mass index, > or = 25), 24% obese (body mass index, > or = 30), and 4% extremely obese (body mass index, > or = 40). The remaining 31% were classified as normal or underweight. First-shock success, cumulative success through two shocks, and cumulative success through the first-shock series were unrelated to body weight, as were basic life support restoration of spontaneous circulation, prehospital restoration of spontaneous circulation, hospital admission, and discharge. CONCLUSIONS: Overweight patients were defibrillated by the biphasic waveform used in this study at high rates, with a fixed energy of 150 J, and without energy escalation.
PURPOSE OF REVIEW: The advent of biphasic waveforms for external defibrillation has generated extensive experimental and clinical investigation. At the same time, it has led to the development and clinical use of biphasic waveforms of several different designs. Finally, other types of waveforms, primarily triphasic, have entered experimental evaluation. RECENT FINDINGS: There is virtually universal agreement that biphasic waveforms, regardless of design, have greater efficacy in defibrillation of ventricular fibrillation and in cardioversion of atrial fibrillation when compared with monophasic waveforms. It remains unresolved, however, whether any specific biphasic waveform has greater clinical superiority than others. Likewise, it remains to be demonstrated whether any biphasic waveform is less injurious to myocardial function than another and whether injury, if it is incurred, is secondary to peak delivered current or to delivered energy. Biphasic truncated exponential waveforms are used by most manufacturers, whereas a rectilinear biphasic waveform and a pulsed waveform also are being used clinically. SUMMARY: Biphasic waveforms have supplanted monophasic waveforms for defibrillation and cardioversion. They include biphasic truncated exponential, rectilinear, and pulsed biphasic versions. At this time, there is no certain evidence of clinical superiority of one waveform over another in terms of either efficacy or myocardial injury.
OBJECTIVE: To describe and evaluate the in-hospital treatment of ventricular arrhythmias and underlying structural heart disease in patients who survive ventricular fibrillation (VF) out-of-hospital cardiac arrest (OHCA) in a region with a high survival rate after hospital discharge. PATIENTS AND METHODS: The study included all patients presenting in Olmsted County, Minnesota, who had experienced OHCA between November 1990 and December 2000 and who underwent defibrillation of VF by an emergency medical service system. RESULTS: Of 200 patients who experienced VF arrest, 138 (69%) survived to hospital admission (7 died in the emergency department before admission), and 79 (40%) were discharged. Of patients who were discharged, 37 (47%) had a reversible cause of the arrest (perimyocardial infarction) and received treatment of the primary process. The other 42 patients who were discharged had ischemic coronary heart disease (CHD) (n=25), nonischemic CHD (n=10), or idiopathic VF (n=7). Four of the patients with CHD but no left ventricular dysfunction were treated with coronary artery bypass grafting or percutaneous coronary intervention alone. A total of 52 patients (66%) were candidates for electrophysiologic testing. Of these patients, 48 (92%) underwent electrophysiologic testing; of these patients, 10 received amiodarone alone, and 35 received an implantable cardioverter-defibrillator (ICD) (of whom 3 also received amiodarone). Patients who did not receive ICD therapy typically presented before 1998 with CHD and underwent coronary artery bypass grafting or percutaneous coronary intervention only. Of 79 patients who were discharged, 14 (18%) with an ICD have received subsequent shocks. Nineteen (24%) of 79 patients have died, 5 of a primary cardiac etiology (including 2 with repeated OHCA). CONCLUSIONS: The VF OHCA survival rate is high in the setting of rapid defibrillation, with 40% of patients being discharged from the hospital. By the end of the 10-year study, more patients were receiving antiarrhythmic therapy, in particular ICD implantation, after hospital admission. Overall, the long-term survival in patients with VF OHCA is favorable.
BACKGROUND: Mortality after out-of-hospital cardiac arrest from ventricular fibrillation is high. Programs focusing on early defibrillation have improved the rate of survival to hospital discharge. We conducted a population-based analysis of the long-term outcome and quality of life of survivors. METHODS: All patients who had an out-of-hospital cardiac arrest between November 1990 and January 2001 who received early defibrillation for ventricular fibrillation in Olmsted County, Minnesota, were included. The survival rate was compared with that of an age-, sex-, and disease-matched (2:1) control population of residents who had not had an out-of-hospital cardiac arrest and with that of age- and sex-matched controls from the general U.S. population. The quality of life was assessed with use of the Medical Outcomes Study 36-item Short-Form General Health Survey (SF-36) and compared with U.S. population norms. RESULTS: Of 200 patients who presented with an out-of-hospital cardiac arrest with ventricular fibrillation, 145 (72 percent) survived to hospital admission (7 died in the emergency department) and 79 (40 percent) were neurologically intact (good overall capability or moderate overall disability) at discharge. The mean (+/-SD) length of follow-up was 4.8+/-3.0 years. Nineteen patients died after discharge from the hospital. The expected five-year survival rate (79 percent) was identical to that among age-, sex-, and disease-matched controls (P=0.68) but lower than that among the age- and sex-matched U.S. population (86 percent, P=0.02). Fifty patients completed SF-36 surveys at the end of follow-up, and the majority had a nearly normal quality of life, with the exception of reduced vitality. CONCLUSIONS: Long-term survival among patients who have undergone rapid defibrillation after out-of-hospital cardiac arrest is similar to that among age-, sex-, and disease-matched patients who did not have out-of-hospital cardiac arrest. The quality of life among the majority of survivors is similar to that of the general population.
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BACKGROUND: Intervening successfully to reduce the burden of sudden out-of-hospital death due to coronary heart disease (OHCD) requires knowledge of where these deaths occur and whether they are observed by bystanders. METHODS: To establish the proportion of OHCDs that were witnessed and where they occurred, we reviewed the coroner's notes and medical records of a previously-described sample of OHCD cases among residents of Olmsted County, Minnesota. This cohort (n=113) consisted of a 10% random sample of all Olmsted County residents who died out-of-hospital between 1981 and 1994 and whose deaths were attributed to coronary heart disease. RESULTS: Excluding deaths in nursing homes (n=27), 71 (83%) of the deaths occurred in private homes and 15 (17%) occurred in public places. The event was not witnessed in 59% of deaths occurring in private homes and in 20% of deaths occurring in public places. The presence or absence of a bystander could not be established for 10% of deaths in private homes and 7% of deaths in public areas. CONCLUSIONS: A significant proportion of OHCDs occur in private homes and are not witnessed. Prevention of unwitnessed deaths will require programs that result in primary prevention and/or calls to first responders at the time of impending cardiac arrest.
Prolongation of the QT interval is a known risk factor for syncope, seizures and sudden cardiac death. Most patients with QT prolongation have an acquired cause, but congenital forms of QT prolongation are being increasingly recognized. However, existing advanced cardiac life support (ACLS) treatment algorithms for prolonged QT mediated ventricular fibrillation pertains to acquired long-QT syndrome (LQTS). Here, a young patient with out-of-hospital cardiac arrest secondary to congenital LQTS illustrates critical exceptions to the current ACLS treatment algorithms for ventricular fibrillation and unstable ventricular tachycardia when QT prolongation is congenital in origin. A clarified ACLS algorithm is proposed.
PRIMARY OBJECTIVE: Automated external defibrillators (AEDs) are used with increasing frequency in the United States by first responders (FR) such as police officers (PO) or firefighters (FF). However, FR satisfaction with use of AEDs has not been investigated. We hypothesized that FR satisfaction is comparable with that of paramedics (PA) and that, among those who have defibrillated with AEDs, those who have restored a pulse before PA arrival have a higher level of satisfaction than those who have not restored a pulse. MATERIALS AND METHODS: A 21-item questionnaire with closed answers was sent to FR and PA in four communities. Each answer was scored 0, 1 or 2. A score between 10 and 16 correlated with the highest satisfaction level. RESULTS: 276 out of 311 questionnaires were returned (89%). Two hundred and eleven respondents (35 PA, 70 FF and 106 PO) had used an AED and 99 FF and PO had restored a pulse before PA arrival. The satisfaction level of PO, FF and PA was high as demonstrated by the scores: 13.26, 13.07 and 13.39, respectively. Use of AED and pulse restoration resulted in higher scores than those of groups who had been trained only and who had not restored a pulse. CONCLUSION: FR demonstrated a high level of satisfaction with using AEDs, and also had a favorable attitude toward implementation of AED use. Restoration of a pulse was clearly a factor responsible for a higher satisfaction. This positive attitude should encourage further implementation of early defibrillation programs in non-medical first responder settings.
PRIMARY OBJECTIVE: Defibrillation is essential for victims of sudden cardiac arrest (SCA) with ventricular fibrillation (VF), yet it does not terminate the underlying causes of VF. Prior to more definitive interventions, these same causes may result in recurrence of VF following defibrillation (refibrillation). The incidence and course of refibrillation, and its relation to patient outcomes, has not been previously described in the context of treatment of out-of-hospital SCA with biphasic waveform automated external defibrillators (AEDs). MATERIALS AND METHODS: ECGs were recovered from all shocks delivered with biphasic AEDs by Basic Life Support (BLS) first responders, primarily police, in witnessed cardiac arrests occurring from December 1996 to December 2001 in the Rochester, MN public service area. Only events prior to administration of cardio-active medications were considered. Frequency and time to occurrence of refibrillation were compared in patients in relation to the progress of their resuscitation and survival. RESULTS AND CONCLUSIONS: One hundred and sixteen of 128 shocks delivered under BLS care to 49 patients with witnessed cardiac arrests presenting with VF terminated VF. Most patients (61%) refibrillated while under BLS care, many (35%) more than once. Occurrence of and time to refibrillation were unrelated to achievement of return of spontaneous circulation (ROSC) under BLS care (BLS ROSC), to survival to hospital discharge and to neurologically intact survival.