Robert Swor

The Public Access Defibrillation (PAD) trial: study design and rationale.

The PAD Trial is a prospective, multicenter, randomized clinical study testing whether volunteer, non-medical responders can improve survival from out-of-hospital cardiac arrest (OOH-CA) by using automated external defibrillators (AEDs). These lay volunteers, who have no traditional responsibility to respond to a medical emergency as part of their primary job description, will form part of a comprehensive, integrated community approach to the treatment of OOH-CA. The study is being conducted at 24 field centers in the United States and Canada. Approximately 1000 community units (e.g. apartment or office buildings, gated communities, sports facilities, senior centers, shopping malls, etc.) were randomized to treatment by trained laypersons who will provide either cardiopulmonary resuscitation (CPR) alone or CPR plus use of an AED, while awaiting arrival of the communitys emergency medical services responders. The primary endpoint is the number of OOH-CA victims who survive to hospital discharge. Secondary endpoints include neurological status, health-related quality of life (HRQL), cost, and cost-effectiveness. Data collection will last approximately 15 months and is expected to be completed in September 2003.

Prehospital 12-Lead ECG: Efficacy or Effectiveness?

Introduction. Previous literature has documented that prehospital 12-lead electrocardiography (ECG) decreases the time to reperfusion in patients with an acute ST-segment elevation myocardial infarction (STEMI). Objective. To compare time to ECG, time to angioplasty suite (laboratory), andtime to reperfusion in emergency medical services (EMS) STEMI patients, who received care through three different processes. Methods. The setting was a large suburban community teaching hospital with emergency department (ED)-initiated single-page acute myocardial infarction (AMI) team activation for STEMI patients. The population was STEMI patients transported by EMS from January 2003 to October 2005. Not all EMS agencies had prehospital 12-lead ECG capability. Paramedics interpret andverbally report clinical assessment andECG findings via radio. The AMI team is activated at the discretion of the emergency physician 1) before patient arrival to the ED based on EMS assessment, 2) after ED evaluation with EMS ECG, or 3) after ED evaluation andED ECG. Time intervals were calculated from ED arrival. To assess the impact of interventions on performance targets, we also report the proportion of patients who arrived in laboratory within 60 minutes andreperfusion within 90 minutes of arrival. Parametric andnonparametric statistics are used for analysis. Results. During the study period, there were 164 STEMI patients transported by EMS; mean age was 66.1 years, and56% were male. Of these, 93 (56.7%) had an EMS ECG and31 (33%) had AMI team activation before ED arrival. Mean time to laboratory for all patients was 49.8 ± 34.4 minutes andtime to reperfusion was 93.2 +/− 34.5 min. Patients with prearrival activation were transported to laboratory sooner (mean, 24.3 vs. 53. 4 minutes; p < 0.001) andreceived reperfusion sooner than all other patients (mean, 70.4 vs. 96.3 minutes; p = 0.007). More prearrival activation patients met performance targets to laboratory (96.7% vs. 73.7%; p = 0.009) andreperfusion (85.2% vs. 51.0%; p = 0.003). There was no difference in time to laboratory or to reperfusion for patients who received EMS ECG but no prearrival activation compared with those who received EMS transport alone. Conclusions. A minority of patients with EMS ECGs had prearrival AMI team activation. EMS ECGs combined with systems that activate hospital resources, but not EMS ECGs alone, decrease time to laboratory andreperfusion.

PREHOSPITAL PAIN MANAGEMENT IN CHILDREN SUFFERING TRAUMATIC INJURY

Prehospital pain management has become an important emergency medical services (EMS) patient care issue. Objectives. To describe the frequency of EMS andemergency department (ED) analgesic administration to injured children; to describe factors associated with the administration of analgesia by EMS; andto assess whether children with lower-extremity fractures receive analgesia as frequently as do adults with similar injuries. Methods. This was a retrospective study of children (age < 21 years) who were transported by EMS between January 2000 andJune 2002 andhad a final hospital diagnosis of extremity fractures or burns. Secondarily, children with lower-extremity fractures were compared with a cohort of EMS-transported adults with similar injuries andtransported during the same study period. Receipt of andtime of parenteral analgesia were recorded. Results. Seventy-three children met the inclusion criteria. The mean (range) age of this sample was 12.4 (0.9–21) years, with only four patients aged < 5 years. A majority of the patients were male (49/73, 67.1%) andsustained femur (20/73, 27.4%) or tibia/fibula (26/73, 35.6%) fractures. Few pediatric patients received prehospital analgesia (16/73, 21.9%), while a majority received analgesia in the ED (58/73, 79.4%). Prehospital analgesia was associated with earlier patient treatment than that administered in the ED (22.3 ± 5.9 min vs. 88.3 ± 38.2 min). Comparing children (n = 33) with adults (n = 76) with similar lower-extremity fractures, a small insignificant difference was found in the rate of prehospital analgesia between children andadults (7/33, 21.2%, vs. 20/56, 26.3%). Conclusion. Few pediatric patients receive prehospital analgesia, although most ultimately received ED analgesia. Few factors were identified that could be associated with EMS oligoanalgesia. No difference was found between children andadults in the rates of EMS analgesia.

Does race or socioeconomic status predict adverse outcome after out of hospital cardiac arrest: a multi-center study.

OBJECTIVEnTo assess whether socioeconomic status (SES) or race is associated with adverse outcome after an out-of-hospital cardiac arrest (OHCA).nnnMETHODSnA convenience sample of OHCA of presumed cardiac origin from seven suburban cities in Michigan, 1991-1996. Median household income (HHI), utilizing patient home address and 1990 census tract data, was dichotomized above and below 1990 state median income. Patient race was dichotomized as black or white. Outcome was defined as survival to hospital discharge (DC). Multiple logistic regression and Pearsons chi2 values were used for analysis.nnnRESULTSnOf 1317 cases with complete data for analysis, the average age was 67.3 +/- 16.0, 939 (71.1%) were white, 587 (44.4%) arrests were witnessed (WIT), and 65 (4.9%) were DC alive. There was no significant difference between races with respect to WIT arrests, V(T)/V(F) arrest rhythms, and a small difference in EMS response interval. Whites were more likely to be above median HHI (57.1 vs. 26.2%, P < 0.001). Adjusted odds ratios for predictors of survival were WIT arrest (OR = 3.76, 95% CI (1.7, 8.2)), V(T)/V(F) (OR = 8.74, 95% CI (3.7, 10.8), but not race (OR = 0.68, 95% CI (0.3, 1.4)) or SES (OR = 1.51, 95% C1 0.8, 2.8).nnnCONCLUSIONnIn this population, neither race nor SES was independently associated with a worse outcome after OHCA.

A randomized controlled trial of chest compression only CPR for older adults-a pilot study.

UNLABELLEDnOlder people are trained infrequently in cardiopulmonary resuscitation (CPR), yet are more likely to witness a cardiac arrest. Older people who are CPR trained perform CPR when witnessing a cardiac arrest.nnnOBJECTIVEnTo assess whether elderly adults (>55 years) who receive chest-compression only cardiopulmonary resuscitation (CC-CPR) training display equivalent skill retention rates compared with those who receive traditional CPR instruction. We also identified factors associated with 3 months skill retention at 3 months in both groups.nnnMETHODSnOlder adults in a suburban hospital Older Adult Services program were invited to participate in an experimental CPR course. The 2 h course was modelled after the AHA Friends and Family course, and used one of two standardized video scenarios. Seventy four subjects were randomized to CC-CPR (n=36) or traditional CPR (n=38) training. Participation consisted of initial training, followed by a 3 months return videotaped assessment. Three months skill competence was assessed either by consensus between two video evaluators, or the on-site evaluator. Chi square and Kappa tests were used for analysis, and unadjusted odds ratios and 95% confidence intervals are reported.nnnRESULTSnSkill retention assessments were completed on 29 (81%) CC-CPR and 26 (68%) CPR trainees. Subjects were elderly (71.5+/-6.69 years), and had a high rate of previous CPR training (58.0%). Groups were similar in demographic characteristics. After training, participants exhibited high rates of perceived competence (86.4%), although the overall 3 months skill retention was low (43.6%). CC-CPR training resulted in equivalent skill retention rates as compared with traditional CPR training (51.7 vs. 44.4%; P=0.586). No participant factors were associated with skill retention, including age, previous CPR training, education level, medical history, or perceived physical ability to perform.nnnCONCLUSIONnWe identified low rates of CPR skill retention in this elderly population. CC-CPR instruction was associated with equivalent skill retention rates compared with traditional CPR instruction. No demographic factors were associated with successful skill retention.

Delay Prior to Calling 9-1-1 Is Associated with Increased Mortality After Out-of-Hospital Cardiac Arrest

Objective. We sought to characterize the collapse-to-9-1-1 call interval, to evaluate the frequency of pre–9-1-1 delay, andto assess whether delay is associated with decreased survival after out-of-hospital cardiac arrest (OHCA). Methods. This was a five-year prospective survey of bystanders to adult OHCA cases in which the victims were transported to seven local teaching hospitals in Michigan. Bystander data were obtained by telephone interview beginning two weeks after the event, andthrough review of emergency medical services (EMS) documents. Criteria for pre–9-1-1 delay were prospectively developed. Two paramedic reviewers were trained on these criteria andreviewed bystander andEMS data for each cardiac arrest case. Multivariate regression analysis was used to assess the independent impact of delay on survival. We collected common bystander andEMS OHCA demographics, as well as bystander description of events prior to the 9-1-1 call. Outcome was survival to hospital discharge. Results. During the study period we identified 1,004 OHCAs, for which 779 bystanders completed interviews. Of these interviews, 688 had adequate data for analysis. Raters showed moderate to strong agreement for a 15% subsample of cases. Of all cases, 330 (48%) were identified as having had pre–9-1-1 delay. Delay was less commonly associated with witnessed arrest (odds ratio [OR] 2.7; 95% confidence interval [CI] 2.0–3.7%) andpublic location (OR 1.57; 95% CI 1.1–2.2%). In a multivariate model, only initial-rhythm ventricular tachycardia/ventricular fibrillation was associated with improved survival (OR 2.28; 95% CI 1.3–4.1), andpre–9-1-1 delay was associated with decreased survival (OR 0.46; 95% CI 0.3–0.9%). Conclusion. This method demonstrated that prehospital delay is common in OHCA andis associated with increased mortality. Measurement of pre–9-1-1 delay may improve precision of predictive models for OHCA survival.

CPR: R ESUSCITATION OF THE A RRESTED H EART

This is one of two texts that have been published recently addressing a fundamental topic to those involved in EMS systems. The spectrum of resuscitation issues from basic science to the ethical issues of withholding or withdrawing resuscitation are important to those health professionals in EMS systems, and are presented in this text by authors from a variety of disciplines, predominately critical care subspecialists. The editors, particularly Dr. Weil, are pioneers in resuscitation research and leaders in the development of the field. They describe this text as being for physicians, nurses, and emergency medical technicians who are clinicians who provide cardiac resuscitation professionally, and who teach cardiopulmonary resuscitation (CPR) to others. I would observe that the level of the text is more suited toward the educator and researcher than clinician. The book is relatively short for a reference text, comprised of 303 pages and 21 chapters. The foreword, by Dr. Myron Weisfeldt, argues that sudden cardiac death (SCD) receives the least attention and resources of all causes of sudden death (trauma, homicide, war) in our society. Dr. Weisfeldt makes the case that with optimal care, we could easily save more lives treating CPR than are murdered. His presentation of the public health problem and potential for treatment of SCD is optimistic, perhaps too optimistic. The first chapter reviews the history of resuscitation and chronicles the efforts to revive the dead from Talmud in 200 BC to the present. Multiple methods to restore ventilation from bellows to inversion to the use of barrels are described and depicted. This is a pleasant overview that places resuscitation in context. The second chapter on epidemiology: etiology, incidence, and survival rates, reviews the incidence of cardiovascular disease in different nations. A relatively brief discussion of the etiology of SCD includes very little information on cardiac causes and surprisingly more space on noncardiac causes. The discussion of risk factors for cardiac arrest is divided into modifiable factors (related to coronary artery disease), fixed factors (race, age, gender, and heredity), and transient factors (medications, ischemia, etc.). This section is of key importance and brief. Finally, the author reviews the factors that impact survival after an out-of-hospital cardiac arrest. Multiple chapters on airway management and ventilation are presented. The first includes a discussion of basic and advanced airway measures. It first addresses manual ventilation with and without equipment, which is helpful. Unfortunately, this chapter (and the rest of this book) does not address the concept of not ventilating a patient during CPR. Traditional advanced airways, including endotrachael intubation, Combitubes, pharyngotracheal lumen airways, and the laryngeal mask airway, are all discussed. A section is devoted to monitoring the effectiveness of CPR but focuses on blood gas analysis, and barely mentions the use of capnography. A later chapter reviews this topic, its limitations during CPR, and its potential for maximizing therapy and improving outcome. The chapter on electrical causes of cardiac arrest and their management embarks on a useful discussion of the etiology of cardiac arrest and the pathophysiology of ventricular fibrillation and ventricular tachycardia. Mechanisms of defibrillation are also discussed, with a brief introduction to the concepts of monophasic vs biphasic waveforms and postdefibrillation myocardial injury. Although a relatively minor issue, risk of defibrillation to the provider is not addressed here or elsewhere. The Advanced Cardiac Life Support (ACLS) algorithms are presented as the preferred (and seemingly only) method of treatment. The next chapter addresses the timely issue of automated external defibrillation. It begins with the startling precept that despite the introduction of CPR, ACLS, and early defibrillation, survival rates from cardiac arrest have not changed in 35 years. The author embarks on a lengthy discussion of rapid defibrillation in Europe and the United States. The literature on early defibrillation is reviewed and a thoughtful discussion of the concept of “public-access defibrillation” is presented. This chapter is extremely well referenced. Basic CPR, as expected, receives a lot of attention. Chapter 6 addresses CPR and its blood flow. The myriad interventions and their clinical trials are also reviewed. Later in another chapter (11), the complicaMEDIA REVIEWS CPR: RESUSCITATION OF THE ARRESTED HEART