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R O Cummins

Publications and source records attributed to R O Cummins.

At least 55 records · Page 3Linked to original sources

Ventricular fibrillation, automatic external defibrillators, and the United States Food and Drug Administration: confrontation without comprehension.

More people die in the United States each day of potentially reversible VF than of any other cause of death, reversible or not. Early defibrillation is the definitive treatment. Automated external defibrillation is a proven technology now confirmed to have saved thousands of lives. As with all medical devices and technology, perfection is not possible. Some problems, such as those represented by the two cases discussed in this article, are inevitable and acceptable and give little cause for alarm. One would not stop penicillin from being manufactured and distributed because of a sudden, unexpected allergic reaction in one patient (error of commission) or an unexpected resistant organism in another (error of omission). The FDA must understand that AEDs, even if they are imperfect, are not anywhere near as dangerous as no defibrillator at all. AEDs have finally allowed many EMS systems to achieve early defibrillation. Discontinuing use of AEDs or closing AED manufacturers could mean a significant number of lives lost unnecessarily. Therefore EMS agencies planning to implement early-defibrillation programs should continue with such plans. Why the agents of an important federal regulatory agency have singled out this technology for an intense review puzzles many observers in the medical-device field. Two meetings have been hosted by officials of the FDA to discuss the continuing concern the FDA officials have expressed over automated defibrillation technology. These meetings included representatives from the AHA, the American College of Cardiology, ACEP, defibrillator manufacturers, and other interested organizations. The FDA leadership has repeatedly focused on data acquired through the FDA Medical Device Reporting systems. Congress requires the FDA to investigate reports of problems with "critical medical devices." Because the indication for the use of a defibrillator is cardiac arrest, there will inevitably be a high association between defibrillator use and patient deaths. FDA personnel may view such reports of device problems in association with patient deaths as evidence that an intrinsically flawed technology has reached the marketplace without rigorous testing and evaluation. From the clinician's perspective, however, these reports represent a small numerator over a huge denominator of daily, lifesaving clinical use. The non-FDA participants at the two meetings have stated that the FDA complaints appear to be random and reveal a lack of understanding of AED technology.(ABSTRACT TRUNCATED AT 400 WORDS)

Algorithms↗

CPR and the single rescuer: at what age should you "call first" rather than "call fast"?

STUDY OBJECTIVE: To determine whether the age-related frequency of ventricular fibrillation (VF) in cardiac arrest supports the guideline that single rescuers should "call first" for all victims of sudden collapse older than 8 years. DESIGN: Analysis of data on all nontraumatic cardiac arrests treated by emergency medical service (EMS) personnel in King County, Washington, between 1976 and 1992. MEASUREMENTS: Age, initial cardiac rhythm, witnessed versus unwitnessed status, whether patient was discharged alive. RESULTS: We analyzed 10,992 cardiac arrests. Initial rhythm was VF in 4,252 (40%) and non-VF in 6,740 (60%). VF frequencies were 3% (0 to 8 years old), 17% (8 to 30 years), and 42% (30 years or older). CONCLUSION: Most patients under age 30 were not in VF at the time of EMS evaluation. Our data suggest that a "call fast" strategy may be more effective when a single rescuer is present and the victim is between 8 and 30 years old.

Adolescent↗

Outcome of insulin-treated diabetics receiving epinephrine during cardiac arrest.

The purpose of this study was to determine the effects of epinephrine in insulin-treated diabetics (DM) compared with nondiabetic (ND) controls during cardiopulmonary resuscitation (CPR). A retrospective analysis from a multicenter study of out-of-hospital cardiac arrest included 62 DM and 1,151 ND. Outcome parameters included return of spontaneous circulation (ROSC), blood pressure (BP), emergency department admissions (EDA), hospital admissions (HA), and hospital discharge (DC). In DM treated with standard-dose epinephrine (SDE), there were trends toward improved ROSC, BP, EDA, and HA compared with ND. DC was not different. With high-dose epinephrine (HDE) these outcomes were not different. Comparison of the outcomes of DM given SDE versus those given HDE were not different. However, none of the DM given HDE (n = 24) were discharged from the hospital. These results suggest that DM may have improved resuscitation rates with SDE and may be adversely affected with HDE. Larger prospective studies are needed to confirm these findings.

Aged↗

Expected death and unwanted resuscitation in the prehospital setting.

STUDY OBJECTIVE: To determine the outcome, location, preexisting conditions, and resuscitation wishes of prehospital cardiac arrest patients. DESIGN: Retrospective review of paramedic and emergency medical technician run reports. SETTING: Urban area with a two-tiered emergency medical services response system covering an area of 2,128 square miles and serving a population of 1,413,900 (in 1988). PARTICIPANTS: All prehospital cardiac arrest patients to which the King County, Washington, Emergency Medical Services (KCEMS) system responded to during a 12-month period. Unless decapitation, decomposition, or dependent lividity existed, all cardiac arrest patients in the KCEMS system received full resuscitative efforts. MEASUREMENTS: We analyzed run reports from 694 cardiac arrest patients, excluding all cardiac arrests from trauma, overdose, or drowning, or obvious signs of extended downtime such as decomposition or dependent lividity. We defined an unwanted resuscitation as a resuscitation attempt despite written or verbal requests by the patient, family, or private physician. We defined a patient as having severe, chronic disease if the run report listed one or more conditions associated with poor survival rates after inpatient CPR. These included cancer, cerebral vascular accident, dementia, renal failure, dialysis, AIDS, thoracic or abdominal aneurysms, cirrhosis, or if the patient was bedridden or was receiving chronic home nursing care. MAIN RESULTS: Overall 16% (103 of 633) of all cardiac arrest patients survived to hospital discharge. Seven percent (47 of 633) of all cardiac arrest patients fit the unwanted resuscitation definition; 2% (one of 47) survived to hospital discharge. Twenty-five percent (158 of 633) of cardiac arrest patients fit the definition of severe chronic disease; 8% (12 of 158) survived to hospital discharge. CONCLUSION: Severe chronic disease and unwanted resuscitation patients comprised one-third of all resuscitation attempts by KCEMS during a 12-month period. Both groups had lower survival rates compared to cardiac arrest patients who did not have severe chronic disease or indications of unwanted resuscitation.

Advance Directives↗

Out-of-hospital transcutaneous pacing by emergency medical technicians in patients with asystolic cardiac arrest.

BACKGROUND: Transcutaneous cardiac pacemakers generate electrical stimuli that pace the heart through external electrodes that adhere to the chest wall. Transcutaneous pacing has been useful in some patients with bradycardia, but its efficacy in patients with asystole and full cardiac arrest has been limited, possibly because of delays in the initiation of pacing. We studied the efficacy of early transcutaneous pacing in patients with out-of-hospital asystolic cardiac arrest. METHODS: For three years we provided transcutaneous pacemakers to about half the fire districts in a large emergency-medical-services system (the intervention group). In these districts, we authorized emergency medical technicians (EMTs) to begin transcutaneous pacing in patients with cardiac arrest and primary asystole or post-defibrillation asystole. Pacing was done as early as possible, before endotracheal intubation or intravenous medication. EMTs in the other fire districts (the control group) treated similar patients with basic cardiopulmonary resuscitation but without transcutaneous pacing. RESULTS: The EMTs in the intervention group initiated transcutaneous pacing in 112 of the 278 patients with primary asystole. Of these patients, 22 (8 percent) were admitted to the hospital, and 11 (4 percent) were discharged. Among the 259 patients treated by the EMTs in the control group, 21 (8 percent) were admitted to the hospital, and 5 (2 percent) were discharged. The two groups did not differ significantly with respect to the rate of hospital admission or survival. Survival after early pacing for post-defibrillation asystole was no better than survival after pacing for primary asystole. CONCLUSIONS: Transcutaneous pacing appears to offer no benefit in patients with asystolic cardiac arrest, even when it is performed as early as possible by EMTs in the field. Our data suggest that the widespread implementation of early transcutaneous pacing for out-of-hospital asystolic cardiac arrest would be ineffective.

Cardiac Pacing, Artificial↗

Initial countershock in the treatment of asystole.

BACKGROUND: Routine provision of defibrillatory countershock (CS) in the initial management of asystolic cardiac arrest has been advocated because certain cases of ventricular fibrillation (VF) may present as asystole (AS). OBJECTIVE: To determine the value of initial CS versus endotracheal intubation and pharmacologic therapy alone in the treatment of asystolic cardiac arrest. DESIGN/PARTICIPANTS: A retrospective analysis of data collected prospectively during a multicenter study of out-of-hospital cardiac arrest. The study subjects were all patients whose initial cardiac arrest rhythm was AS and were treated with standard advanced cardiac life support (ACLS). SETTING: Six urban emergency medical services (EMS) systems. INTERVENTION: Patients in AS were treated initially with CS followed by ACLS therapy (CS Group), and were compared to those patients receiving endotracheal intubation and pharmacologic therapy alone (No CS Group). OUTCOME MEASURES: Those receiving initial CS were compared to those not receiving CS using both Chi-square and logistic regression analysis. Outcome parameters included: rates of return of spontaneous circulation (ROSC), emergency department admission, hospital admission and hospital discharge. RESULTS: Of the 194 patients presenting with AS, 77 received CS as their initial therapy. Of these, 13 (16.9%) had ROSC compared to 27 of the 117 (23.1%) from the No CS Group (P = 0.30). Emergency department and hospital admission rates were not significantly different; 13.0% versus 18.0% (P = 0.36), and 13.0% versus 11.1% (P = 0.69) for CS versus No CS, respectively. None of the patients in the CS Group were discharged alive versus two (1.7%) from No CS (P = 0.52). Of 42 patients with bystander-witnessed cardiac arrests, 13.3% in the CS Group had ROSC compared to 40.7% in the No CS Group (P = 0.07). Emergency department admission rates were 6.7% for the CS Group and 33.3% for the No CS Group (P = 0.07); while hospital admission rates were 6.7% and 22.2%, respectively (P = 0.39). When these comparisons were adjusted for bystander-initiated CPR, CPR interval, and paramedic response interval, the P-values became 0.10, 0.05 and 0.17, respectively. CONCLUSIONS: Although, statistically, the results for both groups were not distinguishable, outcomes for asystolic patients had a tendency to be better when the initial therapy did not involve CS. Larger study populations are recommended to confirm these preliminary observations.

Aged↗

Effect of first-responder automated defibrillation on time to therapeutic interventions during out-of-hospital cardiac arrest. The Multicenter High Dose Epinephrine Study Group.

STUDY OBJECTIVES: The effect of automated defibrillation provided by basic emergency medical technician (EMT) first-responder units on the time intervals to other critical interventions in the management of out-of-hospital cardiac arrests is unknown. The purpose of this study was to define and compare elapsed time intervals to basic CPR, paramedic arrival, initial countershock, endotracheal intubation, IV access, and initial adrenergic drug therapy in first-responder automated defibrillation/paramedic versus basic EMT/paramedic emergency medical services systems. DESIGN: Prospectively collected data from a 15-month multicenter study of out-of-hospital, nontraumatic cardiac arrests were analyzed. The mean time intervals to critical therapeutic interventions between first-responder automated defibrillation/paramedic and basic EMT/paramedic groups were compared using the Student's t-test with Bonferroni correction. SETTING: Three first-responder automated defibrillation/paramedic and three basic EMT/paramedic urban emergency medical services systems. PARTICIPANTS: 1,578 patients with out-of-hospital cardiac arrest. INTERVENTIONS: The first-responder automated defibrillation/paramedic group received initial ECG analysis and/or automated countershock by first-responder/EMTs; the basic EMT/paramedic group received initial ECG analysis and/or manual countershock by paramedics. RESULTS: Elapsed time intervals in minutes +/- SD for first-responder automated defibrillation/paramedic versus basic EMT/paramedic groups, respectively, were as follows: Collapse to CPR, 4.3 +/- 3.9 versus 5.4 +/- 5.2 (P = .017); collapse to countershock, 10.7 +/- 5.9 versus 13.0 +/- 6.0 (P = .017); collapse to paramedic arrival, 13.0 +/- 5.4 versus 10.3 +/- 6.1 (P = .0001); paramedic arrival to IV access, 5.1 +/- 3.9 versus 7.0 +/- 5.0 (P = .0001); paramedic arrival to endotracheal intubation, 4.8 +/- 4.0 versus 6.8 +/- 5.8 (P = .0001); paramedic arrival to initial adrenergic drug therapy, 7.4 +/- 4.5 versus 8.2 +/- 4.7 (P = .015); collapse to IV access, 17.7 +/- 6.1 versus 16.6 +/- 7.4 (P = .10); collapse to endotracheal intubation, 17.3 +/- 6.4 versus 16.6 +/- 7.8 (P = .32); collapse to initial adrenergic drug therapy, 20.4 +/- 6.7 versus 18.1 +/- 7.2 (P = .010). The time intervals from paramedic arrival to IV access, endotracheal intubation, and initial adrenergic drug therapy remained shorter in the first-responder automated defibrillation/paramedic systems despite stratification by presenting cardiac rhythm. CONCLUSION: First-responder automated defibrillation/paramedic systems provide not only shorter times to initial countershock, as compared with basic EMT/paramedic systems, but by having delegated initial countershock to first-responders, they also allow for significantly shorter times from paramedic arrival to IV access, endotracheal intubation, and initial adrenergic drug therapy interventions.

Electric Countershock↗

Moving toward uniform reporting and terminology.

Researchers interested in performing research on prehospital cardiac arrest should carefully review the presentations from the session "Moving Toward Uniform Reporting and Terminology." Although each presentation concentrates on specific research topics, taken together they suggest the next evolutionary steps we should take to conduct such research. We will base these further steps on the following insights. First, all future articles on prehospital cardiac arrest must share a common nomenclature and template for reporting outcomes. The Utstein style has not solved this problem completely, but it is the critical first step. Over the coming years, we must, through continued use, progressively refine the Utstein style. Second, we can no longer depend on research that comes from a single EMS system. Although we have gained important insights from such studies in the past, our expectations of greater validity and generalizability are rising and pushing us toward multicenter, cooperative studies. The International Brain Resuscitation clinical trials and the numerous studies on thrombolytic therapy demonstrate the directions we must head. Third, we must abandon our narrow focus on the pre-hospital experience. Although some studies have avoided this problem, the preponderance of clinical studies on prehospital cardiac arrest fails to gather information on the prearrest condition of the patient, the actual decisions and action taken around the event (witness Kellermann's discussion of death criteria and rules for stopping resuscitation efforts), and the clinical experience after successful resuscitations. Fourth, we can no longer be satisfied with simple statistics on dichotomous (yes/no) survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Data Collection↗

The Utstein style for uniform reporting of data from out-of-hospital cardiac arrest.

The Utstein style for uniform reporting of data from out-of-hospital cardiac arrest was developed to solve a major problem in resuscitation research. Outcome measures related to cardiac arrest are difficult to evaluate or compare because there have been no uniform definitions or uniform agreements on what data to report. Widespread acceptance of the Utstein style will lead to a better understanding of out-of-hospital cardiac arrest.

Data Collection↗

International emergency cardiac care: support, science, and universal guidelines.

Mature resuscitation councils must continue to support educational and training efforts of less-developed countries, but only when strong local interest exists. The scientific basis for the interventions and organization of emergency cardiac care is international in origin. Educational approaches are varied and innovative and should be shared. The era of single national guideline conferences on CPR and emergency cardiac care has ended. Future guideline conferences must cast a broad net to be more international in both participants and scientific knowledge. Existing organizations should support an international infrastructure to help pool scientific and educational expertise.

Cardiopulmonary Resuscitation↗

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.

Emergency Medical Services↗

Emergency medical services and sudden cardiac arrest: the "chain of survival" concept.

Early access to the EMS system helps insure early CPR, defibrillation, and advanced care. Early access is easiest to achieve with 911 systems and widespread community education and publicity. It may also be taught during citizen-CPR classes. Early CPR helps patients by slowing the process of dying, but its effectiveness disappears within minutes, and defibrillation must soon follow. A citizenry well-informed about cardiac emergencies and well-trained in CPR appears to be the best method to achieve early recognition and early CPR. The earliest possible delivery of defibrillation is critical and, almost by itself, sufficient for many sudden death cases. It has, therefore, emerged as the single most effective intervention for patients in nontraumatic cardiac arrest. Automated external defibrillators help accomplish this goal and now permit widespread implementation of a variety of early defibrillation programs. Early advanced care helps those who do not immediately convert to an organized cardiac activity or who do not achieve a spontaneous circulation following early defibrillation. Advanced care allows a system to approach its highest possible survival rate by respiratory and anti-arrhythmic stabilization and monitoring of patients in the post-resuscitation period. At present, early CPR and rapid defibrillation, combined with early advanced care, can result in long-term survival rates as high as 30% for witnessed VF. Because neurological and psychological recovery from cardiac arrest are tied to the time within which these critical interdependent treatment modalities are delivered (1, 87), high resuscitation rates will also lead to a high percentage of patients who recover to their pre-arrest neurologic level. The public health challenge is to develop programs that will allow recognition, access, bystander-CPR, defibrillation, and advanced care to be delivered as quickly as possible, ideally within moments of the collapse of a sudden death victim. Achievement of such a goal requires the deployment of multiple properly directed programs within an EMS system; each program lends strength to the chain of survival, thereby enhancing successful recovery and long-term survival. What benefits would occur if a majority of EMS systems in the United States could establish cost-effective programs with respectable survival rates? The AHA estimates that full implementation of potential life-saving mechanisms in the community may save 10,000-100,000 lives each year in the US (2). If the maximum survival rate for all nontraumatic cardiac arrests in mature EMS systems is about 20% (33) among the annual 400,000 out-of-hospital cardiac arrests, 80,000 persons would be saved (33).(ABSTRACT TRUNCATED AT 400 WORDS)

Cardiopulmonary Resuscitation↗

A comparison of standard-dose and high-dose epinephrine in cardiac arrest outside the hospital. The Multicenter High-Dose Epinephrine Study Group.

BACKGROUND: Experimental and uncontrolled clinical evidence suggests that intravenous epinephrine in doses higher than currently recommended may improve outcome after cardiac arrest. We conducted a prospective, multicenter study comparing standard-dose epinephrine with high-dose epinephrine in the management of cardiac arrest outside the hospital. METHODS: Adult patients were enrolled in the study if they remained in ventricular fibrillation, or if they had asystole or electromechanical dissociation, at the time the first drug was to be administered to treat the cardiac arrest. Patients were randomly assigned to receive either 0.02 mg of epinephrine per kilogram of body weight (standard-dose group, 632 patients) or 0.2 mg per kilogram (high-dose group, 648 patients), both given intravenously. RESULTS: In the standard-dose group 190 patients (30 percent) had a return of spontaneous circulation, as compared with 217 patients (33 percent) in the high-dose group; 136 patients (22 percent) in the standard-dose group and 145 patients (22 percent) in the high-dose group survived to be admitted to the hospital. Twenty-six patients (4 percent) in the standard-dose group and 31 (5 percent) in the high-dose group survived to discharge from the hospital. Ninety-two percent of the patients discharged in the standard-dose group and 94 percent in the high-dose group were conscious at the time of hospital discharge. None of the differences in outcome between the groups were statistically significant. CONCLUSIONS: In this study, we were unable to demonstrate any difference in the overall rate of return of spontaneous circulation, survival to hospital admission, survival to hospital discharge, or neurologic outcome between patients treated with a standard dose of epinephrine and those treated with a high dose.

Aged↗

Transcutaneous cardiac pacing in the treatment of out-of-hospital pediatric cardiac arrests.

STUDY OBJECTIVE: To evaluate the effectiveness of transcutaneous cardiac pacing in out-of-hospital treatment of cardiac arrests in pediatric patients. DESIGN: We describe the outcome of patients treated during a prospective trial of transcutaneous cardiac pacing in the field. We compare their outcome with that of out-of-hospital arrests in submersion patients who were not paced. We identified patients from Seattle and King County Emergency Medical Services reports, hospitals, and medical examiner's registries. MEASUREMENTS AND MAIN RESULTS: Nine patients in cardiac arrest caused by drowning (six) and sudden infant death syndrome (three) were paced in the field. All were less than 6 years old. The one survivor was severely neurologically impaired and died six months later. Transcutaneous cardiac pacing produced electrical capture in two patients but no detectable pulse or blood pressure. Ten submersion patients less than 6 years old in cardiac arrest were not paced. One survived, with mild neurologic impairment at hospital discharge. CONCLUSION: Transcutaneous cardiac pacing was not effective and was not associated with improved survival.

Cardiac Pacing, Artificial↗