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R O Cummins

Publications and source records attributed to R O Cummins.

At least 73 records · Page 4Linked to original sources

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.

Emergencies↗

Cardiac arrest and resuscitation: a tale of 29 cities.

Published reports of out-of-hospital cardiac arrest give widely varying results. The variation in survival rates within each type of system is due, in part, to variation in definitions. To determine other reasons for differences in survival rates, we reviewed published studies conducted from 1967 to 1988 on 39 emergency medical services programs from 29 different locations. These programs could be grouped into five types of prehospital systems based on the personnel who deliver CPR, defibrillation, medications, and endotracheal intubation; the five systems were three types of single-response systems (basic emergency medical technician [EMT], EMT-defibrillation [EMT-D], and paramedic) and two double-response systems (EMT/paramedic and EMT-D/paramedic). Reported discharge rates ranged from 2% to 25% for all cardiac rhythms and from 3% to 33% for ventricular fibrillation. The lowest survival rates occurred in single-response systems and the highest rates in double-response systems, although there was considerable variation within each type of system. Hypothetical survival curves suggest that the ability to resuscitate is a function of time, type, and sequence of therapy. Survival appears to be highest in double-response systems because CPR is started early. We speculate that early CPR permits definitive procedures, including defibrillation, medications, and intubation, to be more effective.

Emergency Medical Services↗

Near-fatal yew berry intoxication treated with external cardiac pacing and digoxin-specific FAB antibody fragments.

The case of a 5-year-old girl who survived a near-fatal ingestion of yew plant leaves after treatment with CPR, transcutaneous pacing, and digoxin-specific FAB antibody fragments is presented. Multiple rhythm disturbances, including profound bradycardia, occurred. She required endotracheal intubation, external chest compressions, and application of a transcutaneous pacemaker. Paced cardiac contractions produced a dramatic improvement in her blood pressure and clinical condition. Two empiric injections of digoxin-specific FAB antibody fragments were administered, after which cardiac function and rhythm gradually improved. She was discharged in her normal state of health three days later. Yew leaves and berries contain several alkaloids that can produce fatal conduction disturbances. Transcutaneous cardiac pacemakers may be lifesaving for patients with transient cardiac toxicity from drug or toxin ingestions. In addition, cross-reactivity between digoxin-specific FAB antibodies and the alkaloids in the yew plant may exist and may have therapeutic importance, although this mechanism was unlikely to have helped our patient.

Bradycardia↗

Survival rates from out-of-hospital cardiac arrest: recommendations for uniform definitions and data to report.

Survival rates for out-of-hospital cardiac arrest vary widely among locations. We surveyed the definitions used in published studies of out-of-hospital cardiac arrest. Data from 74 studies involving 36 communities showed survival rates ranging from 2% to 44%. There were five different case definitions and 11 different definitions of survivors. The absence of uniform definitions prevents meaningful intersystem comparisons, prohibits explorations of hypotheses about effective interventions, and interferes with the efforts of quality assurance. The most satisfactory numerator for a survival rate appears to be survival to hospital discharge; the most appropriate denominator appears to be witnessed adult cardiac arrest of presumed heart disease etiology, with ventricular fibrillation as the initial identified rhythm. Proposed definitions for the data emergency medical services systems should report as they examine their cardiac arrest survival rates are presented.

Emergency Medical Services↗

Frequency and types of medical emergencies among commercial air travelers.

We performed a one-year prospective survey of emergency medical responses to travelers at an international airport to observe the frequency and type of emergencies experienced in flight and before and after travel. Emergency personnel evaluated a total of 1107 people; 754 (68%) were travelers, 232 (21%) were employees of the airport or airlines, and 118 (11%) were area residents. Of the 754 travelers, 190 (25%) experienced their problem during flight; the aircraft made an unscheduled landing for seven of these travelers. The frequency of in-flight emergencies was 1 per 753 inbound flights, or 1 per 39,600 inbound passengers. The most common emergency problems among all travelers were abdominal pain, chest pain, shortness of breath, syncope, and seizures; 25% of the emergencies were caused by minor trauma. The majority of emergencies among air travelers (75% [564/754]) happened on the ground within the air terminal. Most problems (84% [633/754]) were effectively handled by personnel trained as emergency medical technicians. The types of problems encountered suggest that the "doctors only" medical kit now required aboard US air carriers contains clinically useful items and should continue to be required on board.

Aircraft↗

Use of the automatic external defibrillator in homes of survivors of out-of-hospital ventricular fibrillation.

This 57-month study evaluated the use of automatic external defibrillators (AEDs) in the homes of high risk cardiac patients (survivors of out-of-hospital ventricular fibrillation [VF]). The goal was to determine the utility of these devices by trained lay persons in actual cardiac arrest episodes. Ninety-seven survivors of out-of-hospital VF were enrolled in the study; 59 patients received AEDs, and 38 patients served as a control group. During the study period, 7 deaths occurred in the hospital without preceding out-of-hospital cardiac arrest or from noncardiac causes. There were 14 out-of-hospital cardiac arrests, 10 in the AED group and 4 in the control group. There was 1 long-term survivor in the control group. In the AED group, among the 10 cardiac arrests for which the device was available, it was used in 6. Only 2 patients were in VF; 1 was resuscitated with residual neurologic deficits and survived several months. This study observed a small potential for AEDs to save high risk patients.

Aged↗

Training lay persons to use automatic external defibrillators: success of initial training and one-year retention of skills.

This study was conducted to determine the feasibility of recruitment of lay persons to use automatic external defibrillators (AEDs), the effectiveness of their initial training, and the need for and frequency of retraining over time. Volunteers (n = 146), recruited from a variety of settings, included security personnel and administrative staff from large corporate centers, supervisors from senior care and exercise facilities, and employees in high-rise office buildings. Seven sites for 14 AEDs were recruited. In a single, two-hour class, participants learned to identify and respond to cardiac arrest, to notify emergency personnel, to retrieve and attach the semiautomatic (shock advisory) AED, and to respond to instructions presented on the display screen of the device. A skills check list was used to grade each student on performance of cardiopulmonary resuscitation, operation of the device, and time required to deliver an electric countershock. Retesting was performed one or more times after initial training to assess skill retention. The study lasted 1 year. All age groups, both sexes, and each responder type easily learned to operate the AED, with a trend for lower performance scores in people aged greater than 60 years. Performance time and skills declined significantly after initial training, but returned to satisfactory levels after one retraining session and were even higher after two retraining sessions. With retesting, errors that would have prevented delivery of countershocks to patients in ventricular fibrillation were rare (six of 146 tests, 4%). During the year of this study only three cardiac arrests occurred in the study sites.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

From concept to standard-of-care? Review of the clinical experience with automated external defibrillators.

There is now both national and international acceptance of the "principle of early defibrillation," which contends that whoever arrives first at the scene of a cardiac arrest should have a defibrillator. The almost revolutionary technological event that permits widespread implementation of this principle has been the development of automated external defibrillators (AEDs). The simplicity, accuracy, and safety of these devices markedly expands the range of people who can deliver early defibrillation, which includes minimally trained emergency personnel, lay and community responders, and family members of high-risk patients. Even though AEDs now approach the status of "standard of care," the AED, as an example of a new technology, has not followed the classic technology paradigm: conceptualization, experimentation, dissemination, and standard of care. Instead, like many other technical innovations in emergency medicine, the development of AEDs proceeded simultaneously on many fronts, and implementation often occurred before confirmation of important subissues. AEDs may experience the life cycle of many new ideas: initial enthusiasm and widespread adoption, followed by disillusionment and rejection, and finally a mature, proper perspective. Careful implementation and continued evaluation may help emergency personnel avoid periods of disillusionment with AEDs and move steadily and uneventfully to a proper perspective.

Electric Countershock↗

In-flight deaths during commercial air travel. How big is the problem?

Do passenger deaths occur during commercial air travel? If so, how often and from what causes? We reviewed information reported to the International Air Transport Association on in-flight deaths that occurred during commercial air travel for the eight years between 1977 and 1984. Of the 120 airlines in the International Air Transport Association, 42 carriers reported deaths during these eight years. A total of 577 in-flight deaths were recorded, for a reported average of 72 deaths per year. Deaths occurred at average rates of 0.31 per million passengers, 125 per billion passenger-kilometers, and 25.1 per million departures. The majority of those who died were men (66%, 382/577) and middle-aged (mean age, 53.8 years). Most of the individuals (77%, 399/515) reported no health problems prior to travel. Physicians aboard the aircraft offered medical assistance for 43% (247/577) of the deaths. More than half of the deaths (56%, 326/577) seemed to be related to cardiac problems. Sudden unexpected cardiac death was the cause of death in 63% (253/399) of the apparently healthy people and seems to be the major cause of death during air travel. These observations support the initiation of programs to train cabin personnel in the skills of basic cardiopulmonary resuscitation and in the use of automatic external defibrillators.

Adult↗