An overview of global CME/CPD systems.

PURPOSE: Engagement in CME/CPD has a positive impact on healthcare professionals' (HCPs) knowledge, skills, and performance, and on patient outcomes, therefore it is critical to better understand the components of CME/CPD systems that foster engagement, high-quality education, and impact. METHODS: An assessment of CME/CPD systems was conducted using a mixed-methods approach that included interviews with in-country subject matter experts and qualitative and quantitative data from practicing in-country physicians. RESULTS: Results demonstrate areas of consistency in CME/CPD systems across world regions that included: types of educational providers; types of credit; educational formats; self-tracking of participation; high-degree of compliance when education is mandatory; overall satisfaction with available education; strong support for interprofessional education; and lack of alignment or evaluation of engagement in education with population health outcomes. Areas of variation included: whether engagement in education is required as a condition to practice medicine; whether regulations are uniformly applied; if mechanisms to ensure independence existed; and physician perceptions of independence. CONCLUSION: Results of this assessment maybe used by a variety of different stakeholders to assess how well country-level CME/CPD systems are meeting the needs of practicing physicians and determine what, if any, changes might need to be implemented to improve outcomes.

Ventricular fibrillation waveform measures combined with prior shock outcome predict defibrillation success during cardiopulmonary resuscitation.

AIM: Amplitude Spectrum Area (AMSA) and Median Slope (MS) are ventricular fibrillation (VF) waveform measures that predict defibrillation shock success. Cardiopulmonary resuscitation (CPR) obscures electrocardiograms and must be paused for analysis. Studies suggest waveform measures better predict subsequent shock success when combined with prior shock success. We determined whether this relationship applies during CPR. METHODS: AMSA and MS were calculated from 5-second pre-shock segments with and without CPR, and compared to logistic models combining each measure with prior return of organized rhythm (ROR). RESULTS: VF segments from 692 patients were analyzed during CPR before 1372 shocks and without CPR before 1283 shocks. Combining waveform measures with prior ROR increased areas under receiver operating characteristic curves for AMSA/MS with CPR (0.66/0.68 to 0.73/0.74, p<0.001) and without CPR (0.71/0.72 to 0.76/0.76, p<0.001). CONCLUSIONS: Prior ROR improves prediction of shock success during CPR, and may enable waveform measure calculation without chest compression pauses.

A conceptual framework for planning and assessing learning in continuing education activities designed for clinicians in one profession and/or clinical teams.

PURPOSE: The purpose of this article is to provide a more actionable description of the components of the outcomes framework published in 2009. METHODS: Synthesis of recent research in the learning sciences. RESULTS: The authors propose a conceptual framework to be used planning learning activities and assessing learning in CPD. CONCLUSIONS: CPD practitioners will have a more explicit approach to help clinicians provide the very best care to their patients.

An interactive faculty development workshop designed to improve knowledge, skills (competence), attitudes, and practice in interprofessional continuing education.

PURPOSE: Interprofessional continuing education (IPCE) health care educators must plan activities as members of interprofessional teams and deliver activities to an interprofessional audience. Evidence in the literature suggests they are not well prepared to meet this challenge. This paper reviews one strategy to improve the knowledge, skills, attitudes, and practices of IPCE educators. METHODS: Seven faculty development workshops were conducted within the USA, Europe, Asia, and the Middle East. Approximately 250 learners participated in the workshops in total, with 107 in an IRB-approved research study. RESULTS: From the research cohorts demonstrated improved knowledge and skills over a 12-month period. Knowledge and skills scores increased most significantly from baseline to 3 months and remained above baseline at 6-12 months. The workshop was not an effective strategy to improve attitudes towards IPCE, though attitude scores were already high prior to participating. CONCLUSIONS: All participants actively engaged in the workshops. There were no observed differences in engagement by geographic region, gender, age, or profession. Participants stated they were better able to understand the roles of other team members; perspectives of patients, families, and caregivers; and their own roles on clinical teams. Participants described gaining a new appreciation for the complexity of designing IPCE.

Moving from data collection to application: a systematic literature review of surgical capacity assessments and their applications.

BACKGROUND: Over the past decade, assessments of surgical capacity in low- and middle-income countries (LMICs) have contributed to our understanding of barriers to the delivery of surgical services in a number of countries. It is yet unclear, however, how the findings of these assessments have been applied and built upon within the published literature. METHODS: A systematic literature review of surgical capacity assessments in LMICs was performed to evaluate current levels of understanding of global surgical capacity and to identify areas for future study. A reverse snowballing method was then used to follow-up citations of the identified studies to assess how this research has been applied and built upon in the literature. RESULTS: Twenty-one papers reporting the findings of surgical capacity assessments conducted in 17 different LMICs in South Asia, East Asia and Pacific, Latin America and the Caribbean, and sub-Saharan Africa were identified. These studies documented substantial deficits in human resources, infrastructure, equipment, and supplies. Only seven additional papers were identified which applied or built upon the studies. Among these, capacity assessment findings were most commonly used to develop novel tools and intervention strategies, but they were also used as baseline measurements against which updated capacity assessments were compared. CONCLUSIONS: While the global surgery community has made tremendous progress in establishing baseline values of surgical capacity in LMICs around the world, further work is necessary to build upon and apply the foundational knowledge established through these efforts. Capacity assessment data should be coordinated and used in ongoing research efforts to monitor and evaluate progress in global surgery and to develop targeted intervention strategies. Intervention strategy development may also be further incorporated into the evaluation process itself.

Outcomes by rescue shock number during the metabolic phase of porcine ventricular fibrillation resuscitation.

BACKGROUND: Optimal resuscitation duration before the first rescue shock (RS) to maximize the probability of success after prolonged ventricular fibrillation (VF) cardiac arrest remains unknown. The purpose of this study was to determine the occurrence of return of spontaneous circulation (ROSC) and survival by RS attempt after 12 minutes of untreated VF. METHODS: This was a secondary analysis of prospectively collected data from an institutional animal care and use committee-approved protocol. Fifty-three swine (30-35 kg) were instrumented under anesthesia. Ventricular fibrillation was electrically induced. After 12 minutes of untreated VF, cardiopulmonary resuscitation (CPR) was initiated (and continued as necessary (prn)) and a standard dose of epinephrine (0.01 mg/kg) was given (and repeated every 3 (q3) minutes prn). The first RS was delivered after 3 minutes of CPR (and q3 minutes thereafter prn). Each failed RS was followed (in series) by vasopressin (0.57 mg/kg), amiodarone (4.3 mg/kg), and sodium bicarbonate (1 mEq/kg) prn. Resuscitation continued until ROSC or 20-minute elapsed time. The primary outcomes were ROSC and 20-minute survival. Data were analyzed using descriptive statistics. RESULTS: After 3 minutes of resuscitation, 1 animal (1.9% [95% confidence interval {CI, 0.3-10.0]) achieved ROSC on RS1 and survived. After 6 minutes of resuscitation, 17 animals (32.1% [95% CI, 21.1-45.5]) achieved ROSC on RS2 and 15 (28.3% [95% CI, 18.0-41.6]) survived. Twelve additional animals had ROSC and survival with continued resuscitation. In 23 animals, ROSC was never achieved and efforts were terminated per protocol. CONCLUSION: Our data suggest that during the metabolic phase of VF, 3 minutes of CPR and 1 standard dose of epinephrine may be insufficient to achieve ROSC on the first RS attempt. A longer duration of CPR and/or additional vasopressors may increase the likelihood of successful defibrillation.

Developing an interprofessional continuing education symposium for health care educators in Qatar.

An international interprofessional continuing education symposium was developed and implemented by a global faculty team in Qatar in March 2014. This symposium was undertaken as part of the country's goal of improving the quality of health care. After an extensive planning process, health care educators engaged in multiple types of learning experiences to enrich their knowledge and skills. Evaluation data support the value of this experience.

An Overview of Continuing Medical Education/Continuing Professional Development Systems in China: A Mixed Methods Assessment.

Aims of this assessment were to describe requirements for physicians to engage in CME/CPD; explore perceptions of In-Country SMEs of their CME/CPD systems; describe perceptions of In-Country physicians about interprofessional continuing education (IPCE) and independent CME/CPD; and provide recommendations that may be adopted to improve quality and effectiveness. This assessment used a mixed-methods approach that included 1:1 interviews with in-country subject matter experts and an electronic survey capturing qualitative and quantitative data from practicing in-country physicians. This assessment reflects a country invested in the education of its physician workforce. CME/CPD systems have embedded governance structures, organizations authorized to provide education, and a recognized credit system. Governing bodies have implemented regulations to limit influence from commercial interest organizations on CME/CPD, and there is opportunity to expand delivery systems to reach physicians across diverse geographic regions, better align content to individual physicians' gaps and learning needs, and reduce cost. There is opportunity to invest in IPCE within a country with a strong professional hierarchy system. This assessment reflects CME/CPD systems that are relatively mature and identifies several opportunities to expand and enhance systems to better meet educational needs of physicians and to positively impact practice and patient outcomes.

The barriers to interprofessional care for cancer cachexia among Japanese healthcare providers: A nationwide survey.

BACKGROUND: Cancer cachexia is a severe complication of advanced malignancy, with few therapeutic options. To promote interprofessional care for cancer cachexia, healthcare providers' needs should be addressed in detail. This pre-planned subgroup analysis of the Global Educational Needs Evaluation: a systemic interprofessional study in cancer cachexia (GENESIS-CC) survey aimed to identify barriers to interprofessional care of cancer cachexia in Japan. METHODS: A nationwide survey was electronically conducted for healthcare providers in oncological or general healthcare facilities from January to March 2021 in Japan. The Japanese Regional Advisory Board developed a barrier scoring system with 33 from the 58 original survey items to quantify six domains of barriers: (1) lack of confidence, (2) lack of knowledge, (3) barriers in personal practice, (4) barriers in perception, (5) barriers in team practice and (6) barriers in education. The largest possible barrier score was set at 100 points. We compared the scores by profession. RESULTS: A total of 1227 valid responses were obtained from 302 (24.6%) physicians, 252 (20.5%) pharmacists, 236 (19.2%) nurses, 218 (17.8%) dietitians, 193 (15.7%) rehabilitation therapists and 26 (2.0%) other professionals. Overall, 460 (37.5%) were not very or at all confident about cancer cachexia care, 791 (84.1%) agreed or strongly agreed that care was influenced by reimbursement availability and 774 (81.9%) did not have cancer cachexia as a mandatory curriculum. The largest mean barrier score (± standard deviation) was 63.7 ± 31.3 for education, followed by 55.6 ± 21.8 for team practice, 43.7 ± 32.5 for knowledge, 42.8 ± 17.7 for perception and 36.5 ± 16.7 for personal practice. There were statistically significant interprofessional differences in all domains (P < 0.05), especially for pharmacists and nurses with the highest or second highest scores in most domains. CONCLUSIONS: There is a need to improve the educational system and team practices of cancer cachexia for most Japanese healthcare providers, especially pharmacists and nurses. Our study suggests the need to reform the mandatory educational curriculum and reimbursement system on cancer cachexia to promote interprofessional care for cancer cachexia in Japan.

A Bayesian Analysis of a Cognitive-Behavioral Therapy Intervention for High-Risk People on Probation.

This analysis employs a Bayesian framework to estimate the impact of a Cognitive-Behavioral Therapy (CBT) intervention on the recidivism of high-risk people under community supervision. The study relies on the reanalysis of experimental datal using a Bayesian logistic regression model. In doing so, new estimates of programmatic impact were produced using weakly informative Cauchy priors and the Hamiltonian Monte Carlo method. The Bayesian analysis indicated that CBT reduced the prevalence of new charges for total, non-violent, property, and drug crimes. However, the effectiveness of the CBT program varied meaningfully depending on the participant's age. The probability of the successful reduction of drug offenses was high only for younger individuals (<26 years old), while there was an impact on property offenses only for older individuals (>26 years old). In general, the probability of the successful reduction of new charges was higher for the older group of people on probation. Generally, this study demonstrates that Bayesian analysis can complement the more commonplace Null Hypothesis Significance Test (NHST) analysis in experimental research by providing practically useful probability information. Additionally, the specific findings of the reestimation support the principles of risk-needs responsivity and risk-stratified community supervision and align with related findings, though important differences emerge. In this case, the Bayesian estimations suggest that the effect of the intervention may vary for different types of crime depending on the age of the participants. This is informative for the development of evidence-based correctional policy and effective community supervision programming.

Transforming medical education in Liberia through an international community of inquiry.

A critical component of building capacity in Liberia's physician workforce involves strengthening the country's only medical school, A.M. Dogliotti School of Medicine. Beginning in 2015, senior health sector stakeholders in Liberia invited faculty and staff from U.S. academic institutions and non-governmental organizations to partner with them on improving undergraduate medical education in Liberia. Over the subsequent six years, the members of this partnership came together through an iterative, mutual-learning process and created what William Torbert et al describe as a "community of inquiry," in which practitioners and researchers pair action and inquiry toward evidence-informed practice and organizational transformation. Incorporating faculty, practitioners, and students from Liberia and the U.S., the community of inquiry consistently focused on following the vision, goals, and priorities of leadership in Liberia, irrespective of funding source or institutional affiliation. The work of the community of inquiry has incorporated multiple mixed methods assessments, stakeholder discussions, strategic planning, and collaborative self-reflection, resulting in transformation of medical education in Liberia. We suggest that the community of inquiry approach reported here can serve as a model for others seeking to form sustainable global health partnerships focused on organizational transformation.

Japanese macaque encephalomyelitis: a spontaneous multiple sclerosis-like disease in a nonhuman primate.

OBJECTIVE: To describe Japanese macaque encephalomyelitis (JME), a spontaneous inflammatory demyelinating disease occurring in the Oregon National Primate Research Center's (ONPRC) colony of Japanese macaques (JMs, Macaca fuscata). METHODS: JMs with neurologic impairment were removed from the colony, evaluated, and treated with supportive care. Animals were humanely euthanized and their central nervous systems (CNSs) were examined. RESULTS: ONPRC's JM colony was established in 1965 and no cases of JME occurred until 1986. Since 1986, 57 JMs spontaneously developed a disease characterized clinically by paresis of 1 or more limbs, ataxia, or ocular motor paresis. Most animals were humanely euthanized during their initial episode. Three recovered, later relapsed, and were then euthanized. There was no gender predilection and the median age for disease was 4 years. Magnetic resonance imaging of 8 cases of JME revealed multiple gadolinium-enhancing T(1) -weighted hyperintensities in the white matter of the cerebral hemispheres, brainstem, cerebellum, and cervical spinal cord. The CNS of monkeys with JME contained multifocal plaque-like demyelinated lesions of varying ages, including acute and chronic, active demyelinating lesions with macrophages and lymphocytic periventricular infiltrates, and chronic, inactive demyelinated lesions. A previously undescribed gamma-herpesvirus was cultured from acute JME white matter lesions. Cases of JME continue to affect 1% to 3% of the ONPRC colony per year. INTERPRETATION: JME is a unique spontaneous disease in a nonhuman primate that has similarities with multiple sclerosis (MS) and is associated with a novel simian herpesvirus. Elucidating the pathogenesis of JME may shed new light on MS and other human demyelinating diseases.

Development of a surgical capacity index: opportunities for assessment and improvement.

BACKGROUND: Significant gaps exist in the provision of surgical care in low- and middle-income countries (LMICs). The purpose of this study was to develop a metric to monitor surgical capacity in LMICs. METHODS: The World Health Organization developed a survey called the Tool for Situational Analysis to Assess Emergency and Essential Surgical Care. Using this tool, we developed a surgical capacity scoring index and assessed its usefulness with data from Sierra Leone, Liberia, and the Solomon Islands. RESULTS: There were data from 10 hospitals in Sierra Leone, 16 hospitals in Liberia, and 9 hospitals in the Solomon Islands. The levels of surgical capacity were created using our scoring index based on a possible 100 points: level 1 for hospitals with <50 points, level 2 with 50-70 points, level 3 with 70-80 points, and level 4 with >80 points. In Sierra Leone, 44% of the hospitals had a surgical capacity rating of level 1, 50% level 2, and 10% level 3. In Liberia, 37.5% of the hospitals had a surgical capacity rating of level 1, 56.3% level 2, and only one hospital level 3. For Sierra Leone and Liberia, two factors--infrastructure and personnel--had the greatest deficits. In the Solomon Islands, 44.4% of the hospitals had their surgical capacity rated at level 1, 22.2% at level 2, 11.1% at level 3, and 22.2% at level 4. CONCLUSIONS: Pending pilot testing for reliability and validity, it appears that a systematic hospital surgical capacity index can identify areas for improvement and provide an objective measure for monitoring changes over time.

Identification and management of cancer cachexia in patients: Assessment of healthcare providers' knowledge and practice gaps.

BACKGROUND: Cancer cachexia negatively impacts patient outcomes, quality of life and survival. Identification and management of cancer cachexia remains challenging to healthcare professionals (HCPs). The aim of this assessment was to identify current gaps in HCPs' knowledge and practice for identifying and managing adults with cancer-related cachexia. Results may guide development of new educational programmes to close identified gaps and improve outcomes of cancer patients. METHODS: An international assessment was conducted using a mixed-methods approach including focus group interviews with subject matter experts and an electronic survey of practising HCP. The assessment was led by the Society on Sarcopenia, Cachexia and Wasting Disorders (SCWD) and was supported by in-country collaborating organizations. RESULTS: A quantitative survey of 58 multiple-choice questions was completed by physicians, nurses dietitians and other oncology HCP (N = 2375). Of all respondents, 23.7% lacked confidence in their ability to provide care for patients with cancer cachexia. Patients with gastrointestinal, head and neck, pulmonary cancers and leukaemia/lymphoma were reported as those at highest risk for cachexia. Only 29.1% of respondents recognized a key criterion of cancer cachexia as >5% weight loss from baseline, but many (14.4%) did not utilize a standardized definition of cancer cachexia. Despite this, most clinicians (>84%) were able to identify causes of weight loss-reduced oral intake, progressive disease, side effects of therapy and disease-related inflammation. Of all respondents, 52.7% indicated newly diagnosed patients with cancer should be screened for weight loss. In practice, 61.9% reported that patient weight was systematically tracked over time, but only 1125 (47.4%) reported they weigh their cancer patients at each visit. Treatment of cachexia focused on increasing the patient's nutritional intake by oral nutritional supplements (64.2%), energy and protein fortified foods (60.3%) and counselling by a dietitian (57.1%). Whereas many respondents (37.3%) considered cachexia inevitable, most (79.2%) believed that an interprofessional team approach could improve care and that use of standardized tools is critical. CONCLUSIONS: Findings from this international assessment highlight the challenges associated with the care of patients with cancer cachexia, opportunities for interventions to improve patient outcomes and areas of variance in care that would benefit from further analysis.

Myocardial substrate in secondary ventricular fibrillation: insights from quantitative waveform measures.

BACKGROUND: Some patients presenting with nonshockable cardiac arrest rhythms will subsequently manifest ventricular fibrillation. Their prognosis remains poor despite transition to a shockable rhythm. Quantitative waveform measures assess the electrophysiologic status of the fibrillating heart and predict outcome. OBJECTIVE: To use waveform measures to compare those who presented initially with ventricular fibrillation (primary group) with those who manifested ventricular fibrillation after initially presenting with a nonshockable arrest rhythm (secondary group). METHODS: We conducted an observational study using a convenience sample to compare waveform measures of amplitude spectrum area (AMSA), cardioversion output predictor (COP), and detrended fluctuation analysis (DFA) prior to initial shock between the primary (n = 178) and secondary (n = 28) groups. We produced a primary group matched to the secondary group based on the average waveform values to evaluate the observed versus expected outcomes in the secondary group. RESULTS: Survival was 42% in the primary group and 0% in the secondary group. There was a trend toward more favorable waveform values in the primary compared with the secondary group (9.48 versus 9.29, p = 0.10 for AMSA; 13.75 versus 14.12, p = 0.003 for COP; and 0.36 versus 0.44, p = 0.09 for DFA). The restricted, matched primary group experienced a survival of 37%, compared with 0% for the secondary group. CONCLUSIONS: Taken together, the findings suggest that the electrophysiologic status of the heart may be suitable for resuscitation in at least some secondary ventricular fibrillation cases and that other pathophysiology may contribute substantially to the poor prognosis. Alternately, waveform measures may not predict clinical outcomes in secondary ventricular fibrillation.

Current State and Future Opportunities for Continuing Medical Education in Japan.

Globally, CPD systems vary widely. In Japan, the Japanese Medical Association (JMA) is responsible for identifying content and developing education for its speciality practice physicians. The JMA was concerned about persistent low levels of participation in its CME activities and wanted to better understand the root causes. The analysis would provide an opportunity to restructure its programme informed by the needs of its practising clinicians. The JMA engaged a global education provider to conduct an independent analysis of its CME programme. Using a mixed-methods approach, the education provider conducted an on-line survey (N = 338) and held two in-person focus groups (N = 24) to better understand the perspectives of physicians in speciality practice. The on-line survey was sent to over 7,000 practising physicians throughout Japan. Respondents reflected a variety of medical and surgical specialities and length in clinical practice. They described factors that influenced or were barriers to participation in JMA-sponsored education. Respondents also suggested changes to the current model of CME in Japan and expressed an ongoing commitment to life-long learning and achieving the goals set forth in Japan's vision for health care in 2035: Leading the World Through Health. Globally, medical associations are challenged with developing education that meets the needs of a diverse physician workforce. Improved understanding of the perspectives of its physician members and implementation of collaborations with speciality societies may be one strategy to improve quality and address healthcare population needs. Lessons learned from this analysis may help other medical associations with similar challenges.

Effects of pre-arrest and intra-arrest hypothermia on ventricular fibrillation and resuscitation.

BACKGROUND: Hypothermia has been shown to improve survival and neurological outcomes for ventricular fibrillation (VF) cardiac arrest. The electrophysiological mechanisms of hypothermia are not well-understood, nor are the effects of beginning cooling during the resuscitation. METHODS AND RESULTS: We hypothesized that inducing hypothermia prior to the onset of VF would slow the deleterious changes seen in the ECG during VF and that inducing hypothermia at the start of resuscitation would increase the rates of ROSC and short-term survival in a porcine model of prolonged VF. We randomly assigned 42 domestic swine (27.2+/-2.3 kg) to either pretreatment with hypothermia before induction of VF (PRE), normothermic resuscitation (NORM) or intra-resuscitation hypothermia (IRH). During anesthesia, animals were instrumented via femoral cutdown. Lead II ECG was recorded continuously. PRE animals were cooled before the induction of VF, with a rapid infusion of 4 degrees normal saline (30mL/kg). VF was induced electrically, left untreated for 8min, then mechanical CPR began. During CPR the NORM animals got 30mL/kg body-temperature saline and the IRH animals got 30mL/kg 4 degrees saline. In all groups first rescue shocks were delivered after 13min of VF. We calculated the VF scaling exponent (ScE) for the entire 8min period (compared using GEE). ROSC and survival were compared with Fisher's exact test. Mean temperature in degrees C at the onset of VF was PRE=34.7 degrees (+/-0.8), NORM=37.8 (+/-0.9), and IRH=37.9 (+/-0.9). The ScE values over time were significantly lower after 8min in the PRE group (p=0.02). ROSC: PRE=10/14 (71%), NORM=6/14 (43%) and IRH=12/14 (86%); p for IRH vs. NORM=0.02. Survival: PRE=9/14 (64%), NORM=5/14 (36%), IRH 8/14 (57%). CONCLUSION: Hypothermia slowed the decay of the ECG waveform during prolonged VF. IRH improved ROSC but not short-term survival compared to NORM. It is possible to rapidly induce mild hypothermia during CPR using an IV infusion of ice-cold saline.

Ventricular Fibrillation Waveform Analysis During Chest Compressions to Predict Survival From Cardiac Arrest.

BACKGROUND: Quantitative measures of the ventricular fibrillation (VF) ECG waveform can assess myocardial physiology and predict cardiac arrest outcomes, making these measures a candidate to help guide resuscitation. Chest compressions are typically paused for waveform measure calculation because compressions cause ECG artifact. However, such pauses contradict resuscitation guideline recommendations to minimize cardiopulmonary resuscitation interruptions. We evaluated a comprehensive group of VF measures with and without ongoing compressions to determine their performance under both conditions for predicting functionally-intact survival, the study's primary outcome. METHODS: Five-second VF ECG segments were collected with and without chest compressions before 2755 defibrillation shocks from 1151 out-of-hospital cardiac arrest patients. Twenty-four individual measures and 3 combination measures were implemented. Measures were optimized to predict functionally-intact survival (Cerebral Performance Category score ≤2) using 460 training cases, and their performance evaluated using 691 independent test cases. RESULTS: Measures predicted functionally-intact survival on test data with an area under the receiver operating characteristic curve ranging from 0.56 to 0.75 (median, 0.73) without chest compressions and from 0.53 to 0.75 (median, 0.69) with compressions ( P<0.001 for difference). Of all measures evaluated, the support vector machine model ranked highest both without chest compressions (area under the receiver operating characteristic curve, 0.75; 95% CI, 0.73-0.78) and with compressions (area under the receiver operating characteristic curve, 0.75; 95% CI, 0.72-0.78; P=0.75 for difference). CONCLUSIONS: VF waveform measures predict functionally-intact survival when calculated during chest compressions, but prognostic performance is generally reduced compared with compression-free analysis. However, support vector machine models exhibited similar performance with and without compressions while also achieving the highest area under the receiver operating characteristic curve. Such machine learning models may, therefore, offer means to guide resuscitation during uninterrupted cardiopulmonary resuscitation.

Logarithm of the absolute correlations of the ECG waveform estimates duration of ventricular fibrillation and predicts successful defibrillation.

BACKGROUND: Measures of the ventricular fibrillation (VF) waveform may enable better allocation of cardiac arrest treatment by discriminating which patients should receive immediate defibrillation versus alternate therapies such as CPR. We derive a new measure based on the 'roughness' of the VF waveform, the Logarithm of the Absolute Correlations (LAC), and assess and contrast how well the LAC and the previously published scaling exponent (ScE) predict the duration of VF and the likelihood of return of spontaneous circulation (ROSC) under both optimal experimental and commercial-defibrillator sampling conditions. METHODS AND RESULTS: We derived the LAC and ScE from two different populations--an animal study of 44 swine and a retrospective human sample of 158 out-of-hospital VF arrests treated with a commercial defibrillator. In the animal study, the LAC and ScE were calculated on 5s epochs of VF recorded at 1000 samples/s and then down sampled to 125 samples/s. In the human study, the LAC and ScE were calculated using 6s epochs recorded at 200 samples/s that occurred immediately prior to the initial shock. We compared the LAC and ScE measures using the Spearman correlation coefficients (CC) and areas under the receiver operating characteristic curve (AUC). RESULTS: In the animal study, the LAC and ScE were highly correlated at 1000 sample/s (CC=0.93) but not at 125 samples/s (CC=-0.06). These correlations were reflected in how well the measures discriminated VF of < or =5 versus >5 min: AUC at 1000 samples/s was similar for LAC compared to ScE (0.71 versus 0.76). However AUC at 125 samples was greater for LAC compared to ScE (0.75 versus 0.62). In the human study, the LAC measure was a better predictor of ROSC following initial defibrillation as reflected by an AUC of 0.77 for LAC compared to 0.57 for ScE. CONCLUSIONS: The LAC is an improvement over the ScE because the LAC retains its prognostic characteristics at lower ECG sampling rates typical of current clinical defibrillators. Hence, the LAC may have a role in better allocating treatment in resuscitation of VF cardiac arrest.