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Al Hallstrom

Publications and source records attributed to Al Hallstrom.

6 recordsLinked to original sources

Manual chest compression vs use of an automated chest compression device during resuscitation following out-of-hospital cardiac arrest: a randomized trial.

CONTEXT: High-quality cardiopulmonary resuscitation (CPR) may improve both cardiac and brain resuscitation following cardiac arrest. Compared with manual chest compression, an automated load-distributing band (LDB) chest compression device produces greater blood flow to vital organs and may improve resuscitation outcomes. OBJECTIVE: To compare resuscitation outcomes following out-of-hospital cardiac arrest when an automated LDB-CPR device was added to standard emergency medical services (EMS) care with manual CPR. DESIGN, SETTING, AND PATIENTS: Multicenter, randomized trial of patients experiencing out-of-hospital cardiac arrest in the United States and Canada. The a priori primary population was patients with cardiac arrest that was presumed to be of cardiac origin and that had occurred prior to the arrival of EMS personnel. Initial study enrollment varied by site, ranging from late July to mid November 2004; all sites halted study enrollment on March 31, 2005. INTERVENTION: Standard EMS care for cardiac arrest with an LDB-CPR device (n = 554) or manual CPR (n = 517). MAIN OUTCOME MEASURES: The primary end point was survival to 4 hours after the 911 call. Secondary end points were survival to hospital discharge and neurological status among survivors. RESULTS: Following the first planned interim monitoring conducted by an independent data and safety monitoring board, study enrollment was terminated. No difference existed in the primary end point of survival to 4 hours between the manual CPR group and the LDB-CPR group overall (N = 1071; 29.5% vs 28.5%; P = .74) or among the primary study population (n = 767; 24.7% vs 26.4%, respectively; P = .62). However, among the primary population, survival to hospital discharge was 9.9% in the manual CPR group and 5.8% in the LDB-CPR group (P = .06, adjusted for covariates and clustering). A cerebral performance category of 1 or 2 at hospital discharge was recorded in 7.5% of patients in the manual CPR group and in 3.1% of the LDB-CPR group (P = .006). CONCLUSIONS: Use of an automated LDB-CPR device as implemented in this study was associated with worse neurological outcomes and a trend toward worse survival than manual CPR. Device design or implementation strategies require further evaluation. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00120965.

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Consent in resuscitation trials: benefit or harm for patients and society?

CONTEXT: Research in an emergency setting is challenging because there may not be sufficient opportunity or time to obtain informed consent from the patient or their legally authorized representative. Such research can be conducted without prior consent if specific criteria are met. However consent is sometimes required for continued participation and may bias the results of the study. OBJECTIVE: To review regulations related to waiver of consent in emergency research, and evidence of whether such regulations introduce bias. RESULTS: Emergency research can be conducted without consent, either through community disclosure and consultation followed by patient or family notification and consent for continued participation after the intervention was applied, or under a minimal risk waiver. Review of the clinical record is necessary to determine important outcomes such as survival to discharge. If consent is required for this review but not granted, then these data are missing during analysis. If seriously ill or disadvantaged patients are less likely to assent, then investigators cannot determine reliably whether these vulnerable patients were harmed by the intervention. If missing data are different from complete data, then the analysis is susceptible to bias, and the conclusions could be misleading. Extrapolation from non-consent rates in resuscitation studies to results from the DAVID trial demonstrates that the rate of absence of data and information due to lack of assent can influence whether there is a significant difference between treatment groups (survival of control versus intervention: p=0.04 for complete data; p=0.08 for 10.8% lack of assent; p=0.40 for 19.7% lack of assent). CONCLUSIONS: Exception from consent for emergency research should extend to review of the hospital record as the standard in emergency research. The only potential risk to patients associated with review of the clinical record after the intervention is loss of privacy and confidentiality. Appropriate safeguards can be taken to minimize this risk.

Clinical Protocols↗

Do arrhythmia patients improve survival by participating in randomized clinical trials? Observations from the Cardiac Arrhythmia Suppression Trial (CAST)and the Antiarrhythmics Versus Implantable Defibrillators Trial (AVID).

It is debatable whether patients benefit directly from participation in a randomized clinical trial. We attempt to address this question for participants in the Cardiac Arrhythmia Suppression Trial (CAST) and the Antiarrhythmics Versus Implantable Defibrillators (AVID) studies. Survival rates were compared between eligible patients who enrolled in the trials and eligible patients who did not enroll, adjusting for baseline covariates. In CAST, despite that the active therapy was found to confer an almost threefold increased risk of death, survival was similar between the 3163 enrolled and the 1363 nonenrolled eligible patients. However, when patients were under study management, their risk of death was approximately 20% lower than when they left study management. In AVID, overall survival was similar between the 1016 enrolled and the 1246 nonenrolled eligible patients. However, mortality was substantially higher among patients not enrolled because the referring physician mandated the type of therapy. Overall these observational analyses suggest a net improvement in survival for the participants in these two trials.

Arrhythmias, Cardiac↗

Factors determining ICD implantation in drug therapy patients after termination of antiarrythmics versus implantable defibrillators trial.

Because of a significant survival benefit in the defibrillator arm of the Antiarrhythmics versus Implantable Defibrillator (AVID) Trial, patients in the antiarrhythmic drug (AAD) arm were advised to undergo ICD implantation. Despite this recommendation, ICD implantation in AAD patients was variable, with a large number of patients not undergoing ICD implantation. Patients were grouped by those who had been on AAD < 1 year (n = 111) and those on AAD > 1 year (n = 223). Multiple clinical and socioeconomic factors were evaluated to identify those who might be associated with a decision to implant an ICD. The primary reason for patients not undergoing ICD implantation was collected, as well as reasons for a delayed implantation, occurring later than 3 months from study termination. Of 111 patients on AAD for less than 1 year, 53 received an ICD within 3 months compared to 40/223 patients on AAD for more than 1 year (P < 0.001). Patient refusal was the most common reason to not implant an ICD in patients on drug < 1 year; physician recommendation against implantation was the most common in patients on drug > 1 year. Multivariate analysis showed ICD recipients on AAD < 1 year were more likely to be working and have a history of myocardial infarction (MI), while those on AAD > 1 year were more likely to be working, have a history of MI and ventricular fibrillation, and less likely to have experienced syncope, as compared to those who did not get an ICD. Having private insurance may have played a role in younger patients receiving an ICD.

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Survival of antiarrhythmic or implantable cardioverter defibrillator treated patients with varying degrees of left ventricular dysfunction who survived malignant ventricular arrhythmias.

INTRODUCTION: The relative effectiveness of the implantable cardioverter defibrillator (ICD) and antiarrhythmic drugs (AADs) varies with left ventricular ejection fraction (LVEF). However, once an ICD or AAD treatment strategy is chosen, the degree to which the LVEF influences survival is unknown. This article addresses that question. METHODS AND RESULTS: Using patient data from the Antiarrhythmics Versus Implantable Defibrillators (AVID) trial, the impact of LVEF on prognosis of patients who were treated with either an ICD or AAD was assessed. Survival within each quintile of LVEF was estimated by the method of Kaplan-Meier for patients treated with either the ICD or AADs. The Cox proportional hazards model was used to investigate the prognostic value of LVEF for estimating survival after adjustment for other baseline covariates among all patients in the subgroups treated by ICD or AAD. In the highest two quintiles of LVEF, survival was comparable in AAD-treated and ICD-treated patients. In the AAD-treated patients, higher LVEF was significantly and independently associated with survival free of all-cause mortality and arrhythmic death. In the ICD-treated patients, however, the statistical significance of the association was lost and only a trend toward greater survival was present. Death due to congestive heart failure remained independently and significantly associated with survival in both AAD-treated and ICD-treated patients. CONCLUSION: In patients treated with AADs but not patients treated with ICDs, survival is strongly associated with LVEF. The absence of a statistically significant association in the ICD patients is likely related to the effectiveness of the ICD in treating malignant ventricular arrhythmias, but a chance lack of association cannot be excluded.

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