Bentley J. Bobrow

Minimally Interrupted Cardiac Resuscitation by Emergency Medical Services for Out-of-Hospital Cardiac Arrest

CONTEXTnOut-of-hospital cardiac arrest is a major public health problem.nnnOBJECTIVEnTo investigate whether the survival of patients with out-of-hospital cardiac arrest would improve with minimally interrupted cardiac resuscitation (MICR), an alternate emergency medical services (EMS) protocol.nnnDESIGN, SETTING, AND PATIENTSnA prospective study of survival-to-hospital discharge between January 1, 2005, and November 22, 2007. Patients with out-of-hospital cardiac arrests in 2 metropolitan cities in Arizona before and after MICR training of fire department emergency medical personnel were assessed. In a second analysis of protocol compliance, patients from the 2 metropolitan cities and 60 additional fire departments in Arizona who actually received MICR were compared with patients who did not receive MICR but received standard advanced life support.nnnINTERVENTIONnInstruction for EMS personnel in MICR, an approach that includes an initial series of 200 uninterrupted chest compressions, rhythm analysis with a single shock, 200 immediate postshock chest compressions before pulse check or rhythm reanalysis, early administration of epinephrine, and delayed endotracheal intubation.nnnMAIN OUTCOME MEASUREnSurvival-to-hospital discharge.nnnRESULTSnAmong the 886 patients in the 2 metropolitan cities, survival-to-hospital discharge increased from 1.8% (4/218) before MICR training to 5.4% (36/668) after MICR training (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.1-8.9). In the subgroup of 174 patients with witnessed cardiac arrest and ventricular fibrillation, survival increased from 4.7% (2/43) before MICR training to 17.6% (23/131) after MICR training (OR, 8.6; 95% CI, 1.8-42.0). In the analysis of MICR protocol compliance involving 2460 patients with cardiac arrest, survival was significantly better among patients who received MICR than those who did not (9.1% [60/661] vs 3.8% [69/1799]; OR, 2.7; 95% CI, 1.9-4.1), as well as patients with witnessed ventricular fibrillation (28.4% [40/141] vs 11.9% [46/387]; OR, 3.4; 95% CI, 2.0-5.8).nnnCONCLUSIONSnSurvival-to-hospital discharge of patients with out-of-hospital cardiac arrest increased after implementation of MICR as an alternate EMS protocol. These results need to be confirmed in a randomized trial.

Gasping During Cardiac Arrest in Humans Is Frequent and Associated With Improved Survival

Background— The incidence and significance of gasping after cardiac arrest in humans are controversial. Methods and Results— Two approaches were used. The first was a retrospective analysis of consecutive confirmed out-of-hospital cardiac arrests from the Phoenix Fire Department Regional Dispatch Center text files to determine the presence of gasping soon after collapse. The second was a retrospective analysis of 1218 patients with out-of-hospital cardiac arrests in Arizona documented by emergency medical system (EMS) first-care reports to determine the incidence of gasping after arrest in relation to the various EMS arrival times. The primary outcome measure was survival to hospital discharge. An analysis of the Phoenix Fire Department Regional Dispatch Center records of witnessed and unwitnessed out-of-hospital cardiac arrests with attempted resuscitation found that 44 of 113 (39%) of all arrested patients had gasping. An analysis of 1218 EMS-attended, witnessed, out-of-hospital cardiac arrests demonstrated that the presence or absence of gasping correlated with EMS arrival time. Gasping was present in 39 of 119 patients (33%) who arrested after EMS arrival, in 73 of 363 (20%) when EMS arrival was <7 minutes, in 50 of 360 (14%) when EMS arrival time was 7 to 9 minutes, and in 25 of 338 (7%) when EMS arrival time was >9 minutes. Survival to hospital discharge occurred in 54 of 191 patients (28%) who gasped and in 80 of 1027 (8%) who did not (adjusted odds ratio, 3.4; 95% confidence interval, 2.2 to 5.2). Among the 481 patients who received bystander cardiopulmonary resuscitation, survival to hospital discharge occurred among 30 of 77 patients who gasped (39%) versus only 38 of 404 among those who did not gasp (9%) (adjusted odds ratio, 5.1; 95% confidence interval, 2.7 to 9.4). Conclusions— Gasping or abnormal breathing is common after cardiac arrest but decreases rapidly with time. Gasping is associated with increased survival. These results suggest that the recognition and importance of gasping should be taught to bystanders and emergency medical dispatchers so as not to dissuade them from initiating prompt resuscitation efforts when appropriate.

Passive oxygen insufflation is superior to bag-valve-mask ventilation for witnessed ventricular fibrillation out-of-hospital cardiac arrest.

STUDY OBJECTIVEnAssisted ventilation may adversely affect out-of-hospital cardiac arrest outcomes. Passive ventilation offers an alternate method of oxygen delivery for these patients. We compare the adjusted neurologically intact survival of out-of-hospital cardiac arrest patients receiving initial passive ventilation with those receiving initial bag-valve-mask ventilation.nnnMETHODSnThe authors performed a retrospective analysis of statewide out-of-hospital cardiac arrests between January 1, 2005, and September 28, 2008. The analysis included consecutive adult out-of-hospital cardiac arrest patients receiving resuscitation with minimally interrupted cardiopulmonary resuscitation (CPR) consisting of uninterrupted preshock and postshock chest compressions, initial noninvasive airway maneuvers, and early epinephrine. Paramedics selected the method of initial noninvasive ventilation, consisting of either passive ventilation (oropharyngeal airway insertion and high-flow oxygen by nonrebreather facemask, without assisted ventilation) or bag-valve-mask ventilation (by paramedics at 8 breaths/min). The authors determined adjusted neurologically intact survival from hospital and public records and by telephone interview and mail questionnaire. The authors compared adjusted neurologically intact survival between ventilation techniques by using generalized estimating equations.nnnRESULTSnAmong the 1,019 adult out-of-hospital cardiac arrest patients in the analysis, 459 received passive ventilation and 560 received bag-valve-mask ventilation. Adjusted neurologically intact survival after witnessed ventricular fibrillation/ventricular tachycardia out-of-hospital cardiac arrest was higher for passive ventilation (39/102; 38.2%) than bag-valve-mask ventilation (31/120; 25.8%) (adjusted odds ratio [OR] 2.5; 95% confidence interval [CI] 1.3 to 4.6). Survival between passive ventilation and bag-valve-mask ventilation was similar after unwitnessed ventricular fibrillation/ventricular tachycardia (7.3% versus 13.8%; adjusted OR 0.5; 95% CI 0.2 to 1.6) and nonshockable rhythms (1.3% versus 3.7%; adjusted OR 0.3; 95% CI 0.1 to 1.0).nnnCONCLUSIONnAmong adult, witnessed, ventricular fibrillation/ventricular tachycardia, out-of-hospital cardiac arrest resuscitated with minimally interrupted cardiac resuscitation, adjusted neurologically intact survival to hospital discharge was higher for individuals receiving initial passive ventilation than those receiving initial bag-valve-mask ventilation.

Effect of Transport Interval on Out-of-Hospital Cardiac Arrest Survival in the OPALS Study: Implications for Triaging Patients to Specialized Cardiac Arrest Centers

STUDY OBJECTIVEnTo identify any association between out-of-hospital transport interval and survival to hospital discharge in victims of out-of-hospital cardiac arrest.nnnMETHODSnData from the Ontario Prehospital Advanced Life Support Study (January 1, 1991, to December 31, 2002), an Utstein-compliant registry of out-of-hospital cardiac arrest patients from 21 communities, were analyzed. Logistic regression identified factors that were independently associated with survival in consecutive adult, nontraumatic, out-of-hospital cardiac arrest patients and in the subgroup with return of spontaneous circulation.nnnRESULTSnA total of 18,987 patients met criteria and 15,559 (81.9%) had complete data for analysis (study group). Return of spontaneous circulation was achieved in 2,299 patients (14.8%), and 689 (4.4%) survived to hospital discharge. Median transport interval was 4.0 minutes (25th quartile 3.0 minutes; 75th quartile 6.2 minutes) for survivors and 4.2 minutes (25th quartile 3.0, 75th quartile 6.2) for nonsurvivors. Logistic regression revealed multiple factors that were independently associated with survival: witnessed arrest (odds ratio 2.61; 95% confidence interval [CI] 2.05 to 3.34), bystander cardiopulmonary resuscitation (odds ratio 2.22; 95% CI 1.82 to 2.70), initial rhythm of ventricular fibrillation/tachycardia (odds ratio 2.22; 95% CI 1.97 to 2.50), and shorter emergency medical services (EMS) response interval (odds ratio 1.26; 95% CI 1.20 to 1.33). There was no association between transport interval and survival in either the study group (odds ratio 1.01; 95% CI 0.99 to 1.05) or the return of spontaneous circulation subgroup (odds ratio 1.04; 95% CI 0.99, 1.08).nnnCONCLUSIONnIn a large out-of-hospital cardiac arrest study from demographically diverse EMS systems, longer transport interval was not associated with decreased survival. Given the growing evidence showing major influence from specialized postarrest care, these findings support conducting clinical trials that assess the effectiveness and safety of bypassing local hospitals to take patients to regional cardiac arrest centers.

Stroke Team Remote Evaluation Using a Digital Observation Camera in Arizona The Initial Mayo Clinic Experience Trial

Background and Purpose— Telemedicine techniques can be used to address the rural–metropolitan disparity in acute stroke care. The Stroke Team Remote Evaluation Using a Digital Observation Camera (STRokE DOC) trial reported more accurate decision making for telemedicine consultations compared with telephone-only and that the California-based research network facilitated a high rate of thrombolysis use, improved data collection, low risk of complications, low technical complications, and favorable assessment times. The main objective of the STRokE DOC Arizona TIME (The Initial Mayo Clinic Experience) trial was to determine the feasibility of establishing, de novo, a single-hub, multirural spoke hospital telestroke research network across a large geographical area in Arizona by replicating the STRokE DOC protocol. Methods— Methods included prospective, single-hub, 2-spoke, randomized, blinded, controlled trial of a 2-way, site-independent, audiovisual telemedicine system designed for remote examination of adult patients with acute stroke versus telephone consultation to assess eligibility for treatment with intravenous thrombolysis. The primary outcome measure was whether the decision to give thrombolysis was correct. Secondary outcomes were rate of thrombolytic use, 90-day functional outcomes, incidence of intracerebral hemorrhages, and technical observations. Results— From December 2007 to October 2008, 54 patients were assessed, 27 of whom were randomized to each arm. Mean National Institutes of Health Stroke Scale score at presentation was 7.3 (SD 6.2) points. No consultations were aborted; however, technical problems (74%) were prevalent in the telemedicine arm. Overall, the correct treatment decision was established in 87% of the consultations. Both modalities, telephone (89% correct) and telemedicine (85% correct), performed well. Intravenous thrombolytic treatment was used in 30% of the telemedicine and telephone consultations. Good functional outcomes at 90 days were not significantly different. There were no statistically significant differences in mortality (4% in telemedicine and 11% in telephone) or rates of intracerebral hemorrhage (4% in telemedicine and 0% in telephone). Conclusions— It is feasible to extend the original STRokE DOC trial protocol to a new state and establish an operational single-hub, multispoke rural hospital telestroke research network in Arizona. The trial was not designed to have sufficient power to detect a difference between the 2 consultative modes: telemedicine and telephone-only. Whether by telemedicine or telephone consultative modalities, there were appropriate treatment decisions, high rates of thrombolysis use, improved data collection, low rates of intracerebral hemorrhage, and equally favorable time requirements. The learning curve was steep for the hub and spoke personnel of the new telestroke network, as reflected by frequent technical problems. Overall, the results support the effectiveness of highly organized and structured stroke telemedicine networks for extending expert stroke care into rural remote communities lacking sufficient neurological expertise.

Smartphone Teleradiology Application Is Successfully Incorporated Into a Telestroke Network Environment

Background and Purpose— ResolutionMD mobile application runs on a Smartphone and affords vascular neurologists access to radiological images of patients with stroke from remote sites in the context of a telemedicine evaluation. Although reliability studies using this technology have been conducted in a controlled environment, this study is the first to incorporate it into a real-world hub and spoke telestroke network. The study objective was to assess the level of agreement of brain CT scan interpretation in a telestroke network between hub vascular neurologists using ResolutionMD, spoke radiologists using a Picture Archiving and Communications System, and independent adjudicators. Methods— Fifty-three patients with stroke at the spoke hospital consented to receive a telemedicine consultation and participate in a registry. Each CT was evaluated by a hub vascular neurologist, a spoke radiologist, and by blinded telestroke adjudicators, and agreement over clinically important radiological features was calculated. Results— Agreement (&kgr; and 95% CI) between hub vascular neurologists using ResolutionMD and (1) the spoke radiologist; and (2) independent adjudicators, respectively, were: identification of intracranial hemorrhage 1.0 (0.92–1.0), 1.0 (0.93–1.0), neoplasm 1.0 (0.92–1.0), 1.0 (0.93–1.0), any radiological contraindication to thrombolysis 1.0 (0.92–1.0), 0.85 (0.65–1.0), early ischemic changes 0.62 (0.28–0.96), 0.58 (0.30–0.86), and hyperdense artery sign 0.40 (0.01–0.80), 0.44 (0.06–0.81). Conclusions— CT head interpretations of telestroke network patients by vascular neurologists using ResolutionMD on Smartphones were in excellent agreement with interpretations by spoke radiologists using a Picture Archiving and Communications System and those of independent telestroke adjudicators using a desktop viewer. Clinical Trial Registration Information— www.clinicaltrials.gov unique identifier NCT00829361.

Independent Evaluation of an Out-of-hospital Termination of Resuscitation (TOR) Clinical Decision Rule

OBJECTIVESnRecently, investigators described a clinical decision rule for termination of resuscitation (TOR) designed to help determine whether to terminate emergency medical services (EMS) resuscitative efforts for out-of-hospital cardiac arrests (OOHCA). The authors sought to evaluate the hypothesis that TOR would predict no survival for patients in an independent cohort of patients with OOHCA.nnnMETHODSnThis was a retrospective cohort analysis conducted in the state of Arizona. Consecutive, adult, OOHCA were prospectively evaluated from October 2004 through October 2006. A statewide OOHCA database utilizing Utstein-style reporting from 30 different EMS systems was used. Data were abstracted from EMS first care reports and hospital discharge records. The TOR guidelines predict that no survival to hospital discharge will occur if 1) an OOHCA victim does not have return of spontaneous circulation (ROSC), 2) no shocks are administered, and 3) the arrest is not witnessed by EMS personnel. Data were entered into a structured database. Continuous data are presented as means (+/-standard deviations [SD]) and categorical data as frequency of occurrence, and 95% confidence intervals (CIs) were calculated as appropriate. The primary outcome measure was to determine if any cohort member who met TOR criteria survived to hospital discharge.nnnRESULTSnThere were 2,239 eligible patients; the study group included 2,180 (97.4%) patients for whom the data were complete; mean age was 64 (+/-11) years, and 35% were female. The majority of patients in the study group met at least one or more of the TOR criteria. A total of 2,047 (93.8%) patients suffered from cardiac arrest that was unwitnessed by EMS; 1,653 (75.8%) had an unwitnessed arrest and no ROSC. With respect to TOR, 1,160 of 2,180 (53.2%) patients met all three criteria; only one (0.09%; 95% CI = 0% to 0.5%) survived to hospital discharge.nnnCONCLUSIONSnThe authors evaluated TOR guidelines in an independent, statewide OOHCA database. The results are consistent with the findings of the TOR investigation and suggest that this algorithm is a promising tool for TOR decision-making in the field.

Establishing Arizona's statewide cardiac arrest reporting and educational network.

Background. Only a few large cities have published their out-of-hospital cardiac arrest (OHCA) survival statistics using the Utstein style reporting method. To date, to the best of our knowledge there has been no published OHCA survival data for a state. Objective. To describe the process, benefits, andchallenges of establishing a statewide OHCA database andeducational network. Methods. Arizonas Bureau of Emergency Medical Services andTrauma System initiated a statewide, prospective, observational cohort review of all OHCA victims on whom resuscitation was attempted in the field. Emergency medical services (EMS) first care reports, voluntarily submitted by 35 departments in Arizona, were analyzed. We chronicled the development of our data-collection process along with how we obtained patient outcomes anddelivered feedback to field providers. Entry data included time intervals andnodal events conforming to the Utstein style template. Results. In data collected between January 1, 2005, andApril 1, 2006, there were 1,484 OHCAs reported, of which 1,104 were of presumed cardiac etiology occurring prior to EMS arrival. The OHCA incidence was approximately 0.44 per 1,000 population per year. In our database, bystander CPR provided an odds ratio of 3.0 for survival (95% confidence interval 1.3, 6.7). Outcomes for 1,076 patients were obtained. Thirty-seven (3.4%) of the 1,076 cardiac arrest victims survived to hospital discharge. Twenty-seven (8.6%) of the 331 ventricular fibrillation cardiac arrest victims survived to hospital discharge. Conclusion. It is feasible for a public health agency to implement a voluntary, statewide data-collection system andeducational network to determine andimprove survival from OHCA.

NIH Roundtable on Opportunities to Advance Research on Neurologic and Psychiatric Emergencies

STUDY OBJECTIVEnThe Institute of Medicine Committee on the Future of Emergency Care in the United States Health System (2003) identified a need to enhance the research base for emergency care. As a result, a National Institutes of Health (NIH) Task Force on Research in Emergency Medicine was formed to enhance NIH support for emergency care research. Members of the NIH Task Force and academic leaders in emergency care participated in 3 Roundtable discussions to prioritize current opportunities for enhancing and conducting emergency care research. We identify key research questions essential to advancing the science of emergency care and discuss the barriers and strategies to advance research by exploring the collaboration between NIH and the emergency care community.nnnMETHODSnExperts from emergency medicine, neurology, psychiatry, and public health assembled to review critical areas in need of investigation, current gaps in knowledge, barriers, and opportunities. Neurologic emergencies included cerebral resuscitation, pain, stroke, syncope, traumatic brain injury, and pregnancy. Mental health topics included suicide, agitation and delirium, substances, posttraumatic stress, violence, and bereavement.nnnRESULTSnPresentations and group discussion firmly established the need for translational research to bring basic science concepts into the clinical arena. A coordinated continuum of the health care system that ensures rapid identification and stabilization and extends through discharge is necessary to maximize overall patient outcomes. There is a paucity of well-designed, focused research on diagnostic testing, clinical decisionmaking, and treatments in the emergency setting. Barriers include the limited number of experienced researchers in emergency medicine, limited dedicated research funding, and difficulties of conducting research in chaotic emergency environments stressed by crowding and limited resources. Several themes emerged during the course of the roundtable discussion, including the need for development of (1) a research infrastructure for the rapid identification, consent, and tracking of research subjects that incorporates innovative informatics technologies, essential for future research; (2) diagnostic strategies and tools necessary to understand key populations and the process of medical decisionmaking, including the investigation of the pathobiology of symptoms and symptom-oriented therapies; (3) collaborative research networks to provide unique opportunities to form partnerships, leverage patient cohorts and clinical and financial resources, and share data; (4) formal research training programs integral for creating new knowledge and advancing the science and practice of emergency medicine; and (5) recognition that emergency care is part of an integrated system from emergency medical services dispatch to discharge. The NIH Roundtable Opportunities to Advance Research on Neurological and Psychiatric Emergencies created a framework to guide future emergency medicine-based research initiatives.nnnCONCLUSIONnEmergency departments provide the portal of access to the health care system for most patients with acute neurologic and psychiatric illness. Emergency physicians and colleagues are primed to investigate neurologic and psychiatric emergencies that will directly improve the delivery of care and patient outcomes.

The state of emergency stroke resources and care in rural Arizona: a platform for telemedicine.

A rural-urban disparity exists in acute stroke management practices in Arizona. A proposed solution is a statewide acute stroke care plan centered on stroke telemedicine. Our purpose was to evaluate the emergency stroke resources available at and care provided by remote Arizona hospitals and to formulate a 5-year stroke telemedicine plan for Arizona rural residents. We used the Arizona Hospital and Healthcare Association Web site to identify all eligible institutions. Consenting personnel were mailed the survey on behalf of the Arizona Department of Health Services. To construct the 5-year telemedicine plan, we used survey data as well as our previously designed stroke telemedicine research trial. We estimated the resources, the geographic coverage, and the operating costs. Thirty-five hospitals met survey eligibility criteria; however, 24/35 (69%) hospitals completed the survey. Only one hospital had neurologists on call 24/7. Hospitals thrombolysed 2%-4% of all stroke patients annually. Ninety percent of the hospitals were interested in participating in a statewide telemedicine initiative. The stroke telemedicine plan divided Arizona into two regions, each with a one-hub to three-spoke ratio. The budget was estimated to be U.S.