Dynamic electrocardiogram changes are a novel risk marker for sudden cardiac death.

BACKGROUND AND AIMS: Electrocardiogram (ECG) abnormalities have been evaluated as static risk markers for sudden cardiac death (SCD), but the potential importance of dynamic ECG remodelling has not been investigated. In this study, the nature and prevalence of dynamic ECG remodelling were studied among individuals who eventually suffered SCD. METHODS: The study population was drawn from two prospective community-based SCD studies in Oregon (2002, discovery cohort) and California, USA (2015, validation cohort). For this present sub-study, 231 discovery cases (2015-17) and 203 validation cases (2015-21) with ≥2 archived pre-SCD ECGs were ascertained and were matched to 234 discovery and 203 validation controls based on age, sex, and duration between the ECGs. Dynamic ECG remodelling was measured as progression of a previously validated cumulative six-variable ECG electrical risk score. RESULTS: Oregon SCD cases displayed greater electrical risk score increase over time vs. controls [+1.06 (95% confidence interval +0.89 to +1.24) vs. -0.05 (-0.21 to +0.11); P < .001]. These findings were successfully replicated in California [+0.87 (+0.7 to +1.04) vs. -0.11 (-0.27 to 0.05); P < .001]. In multivariable models, abnormal dynamic ECG remodelling improved SCD prediction over baseline ECG, demographics, and clinical SCD risk factors in both Oregon [area under the receiver operating characteristic curve 0.770 (95% confidence interval 0.727-0.812) increased to area under the receiver operating characteristic curve 0.869 (95% confidence interval 0.837-0.902)] and California cohorts. CONCLUSIONS: Dynamic ECG remodelling improved SCD risk prediction beyond clinical factors combined with the static ECG, with successful validation in a geographically distinct population. These findings introduce a novel concept of SCD dynamic risk and warrant further detailed investigation.

Effect of a Mobile Integrated Hospice Healthcare Program on Emergency Medical Services Transport to the Emergency Department.

Objective: To evaluate the effect of a Mobile Integrated Hospice Healthcare (MIHH) program including hospice education and expansion of paramedic scope of practice to use hospice medication kits. Primary outcome was the effect on hospice patient transport to the Emergency Department. Secondary outcomes included reasons for patient transport and review of MIHH kit utilization. Methods: In 2015, the project was implemented in Ventura County, California in collaboration with county emergency medical services (EMS) agency, first response/transport organizations, and hospice programs. Paramedic supervisors received 30 hours of hospice training focusing on palliative care, grief and crisis counseling. When 9-1-1 was called for a patient, EMS first responders arrived on scene, determined a patient was enrolled in hospice and then contacted trained MIHH. Results: Six months (2/2015-7/2015) prior to project implementation the percentage of hospice patients transported to the ED averaged 80.3% (98/122). During the first (8/2015-7/2016), second (8/2016-7/2017) and third year (8/2017-7/2018) after project implementation, the percentage of hospice patients transported to the ED was 36.2% (68/188), 33.2% (63/190) and 24.8% (36/145) respectively. A total of 523 hospice patients were cared for by MIHH during this three-year interval. Of those hospice patients transported, the most common reason for transport was fall/trauma. The MIHH hospice kit was only used once in the field. Odds ratio for hospice transportation to the ED before and after project implementation was 0.125 (95% Confidence Interval: 0.077 to 0.201; p < 0.0001). This represents an absolute reduction risk of 46.6% (95% Confidence Interval: 38.53% to 54.72%). Conclusion: MIHH decreased the transportation of hospice patients to the ED. MIHH provided hospice education, provided family grief support and developed treatment plans with hospice nurses. An expanded scope of practice, including a paramedic hospice kit, was not contributory to this decrease.

Design, Application and Infield Validation of a Pre-Hospital Emergent Large Vessel Occlusion Screening Tool: Ventura Emergent Large Vessel Occlusion Score.

BACKGROUND: The outcome of endovascular treatment for emergent large vessel occlusion (ELVO) is dependent on timely recanalization. To identify ELVO in the field, we present a simplified score, which has been applied and validated in the field by emergency medical services (EMS). Methods and Analysis: Ventura ELVO Scale (VES) comprise of 4 components: Eye Deviation, Aphasia, Neglect, and Obtundation with score range 0-4. The score of greater than or equal to 1 will be considered as ELVO positive. A positive VES along with positive Cincinnati scale prompts ELVO activation. EMS then notify to neurointervention protocol at the receiving stroke center. The performance of VES was evaluated retrospectively. For statistical analysis, SAS version 9.4 was used and Fisher's modelling was used for the comparative analysis. RESULTS: Total 184 patients were included in the final analysis, 62 (33.7%) patients were called VES positive from the field. Out of 62, 36 (58%) patients had ELVO. The mean NIHSS on arrival was 16 in VES positive and 5 in VES negative patients. VES was 94.7% sensitive and 82.4% specific while the PPV and NPV of VES were 58.1% and 98.4%, respectively. It showed 84.9% accuracy. CONCLUSIONS: VES is an effective and simplified prehospital screening tool for detection of ELVO in the field. Its implementation can beat the target door to groin time to improve outcomes and in future it can be used for rerouting of ELVO patients to comprehensive stroke center.

Artificial Intelligence Model Predicts Sudden Cardiac Arrest Manifesting With Pulseless Electric Activity Versus Ventricular Fibrillation.

BACKGROUND: There is no specific treatment for sudden cardiac arrest (SCA) manifesting as pulseless electric activity (PEA) and survival rates are low; unlike ventricular fibrillation (VF), which is treatable by defibrillation. Development of novel treatments requires fundamental clinical studies, but access to the true initial rhythm has been a limiting factor. METHODS: Using demographics and detailed clinical variables, we trained and tested an AI model (extreme gradient boosting) to differentiate PEA-SCA versus VF-SCA in a novel setting that provided the true initial rhythm. A subgroup of SCAs are witnessed by emergency medical services personnel, and because the response time is zero, the true SCA initial rhythm is recorded. The internal cohort consisted of 421 emergency medical services-witnessed out-of-hospital SCAs with PEA or VF as the initial rhythm in the Portland, Oregon metropolitan area. External validation was performed in 220 emergency medical services-witnessed SCAs from Ventura, CA. RESULTS: In the internal cohort, the artificial intelligence model achieved an area under the receiver operating characteristic curve of 0.68 (95% CI, 0.61-0.76). Model performance was similar in the external cohort, achieving an area under the receiver operating characteristic curve of 0.72 (95% CI, 0.59-0.84). Anemia, older age, increased weight, and dyspnea as a warning symptom were the most important features of PEA-SCA; younger age, chest pain as a warning symptom and established coronary artery disease were important features associated with VF. CONCLUSIONS: The artificial intelligence model identified novel features of PEA-SCA, differentiated from VF-SCA and was successfully replicated in an external cohort. These findings enhance the mechanistic understanding of PEA-SCA with potential implications for developing novel management strategies.

Sudden Cardiac Arrest During Sports Activity in Older Adults.

BACKGROUND: Sports activity among older adults is rising, but there is a lack of community-based data on sports-related sudden cardiac arrest (SrSCA) in the elderly. OBJECTIVES: In this study, the authors investigated the prevalence and characteristics of SrSCA among subjects ≥65 years of age in a large U.S. METHODS: All out-of-hospital sudden cardiac arrests (SCAs) were prospectively ascertained in the Portland, Oregon, USA, metro area (2002-2017), and Ventura County, California, USA (2015-2021) (catchment population ∼1.85 million). Detailed information was obtained for SCA warning symptoms, circumstances, and lifetime clinical history. Subjects with SCA during or within 1 hour of cessation of sports activity were categorized as SrSCA. RESULTS: Of 4,078 SCAs among subjects ≥65 years of age, 77 were SrSCA (1.9%; 91% men). The crude annual SrSCA incidence among age ≥65 years was 3.29/100,000 in Portland and 2.10/100,000 in Ventura. The most common associated activities were cycling, gym activity, and running. SrSCA cases had lower burden of cardiovascular risk factors (P = 0.03) as well as comorbidities (P < 0.005) compared with non-SrSCA. Based on conservative estimates of community residents ≥65 years of age who participate in sports activity, the SrSCA incidence was 28.9/100,000 sport participation years and 18.4/100,000 sport participation years in Portland and Ventura, respectively. Crude survival to hospital discharge rate was higher in SrSCA, but the difference was nonsignificant after adjustment for confounding factors. CONCLUSIONS: Among free-living community residents age ≥65 years, SrSCA is uncommon, predominantly occurs in men, and is associated with lower disease burden than non-SrSCA. These results suggest that the risk of SrSCA is low, and probably outweighed by the high benefit of exercise.

Warning symptoms associated with imminent sudden cardiac arrest: a population-based case-control study with external validation.

BACKGROUND: Sudden cardiac arrest is a global public health problem with a mortality rate of more than 90%. Prearrest warning symptoms could be harnessed using digital technology to potentially improve survival outcomes. We aimed to estimate the strength of association between symptoms and imminent sudden cardiac arrest. METHODS: We conducted a case-control study of individuals with sudden cardiac arrest and participants without sudden cardiac arrest who had similar symptoms identified from two US community-based studies of patients with sudden cardiac arrest in California state, USA (discovery population; the Ventura Prediction of Sudden Death in Multi-Ethnic Communities [PRESTO] study), and Oregon state, USA (replication population; the Oregon Sudden Unexpected Death Study [SUDS]). Participant data were obtained from emergency medical services reports for people aged 18-85 years with witnessed sudden cardiac arrest (between Feb 1, 2015, and Jan 31, 2021) and an inclusion symptom. Data were also obtained from corresponding control populations without sudden cardiac arrest who were attended by emergency medical services for similar symptoms (between Jan 1 and Dec 31, 2019). We evaluated the association of symptoms with sudden cardiac arrest in the discovery population and validated our results in the replication population by use of logistic regression models. FINDINGS: We identified 1672 individuals with sudden cardiac arrest from the PRESTO study, of whom 411 patients (mean age 65·7 [SD 12·4] years; 125 women and 286 men) were included in the analysis for the discovery population. From a total of 76 734 calls to emergency medical services, 1171 patients (mean age 61·8 [SD 17·3] years; 643 women, 514 men, and 14 participants without data for sex) were included in the control group. Patients with sudden cardiac arrest were more likely to have dyspnoea (168 [41%] of 411 vs 262 [22%] of 1171; p<0·0001), chest pain (136 [33%] vs 296 [25%]; p=0·0022), diaphoresis (50 [12%] vs 90 [8%]; p=0·0059), and seizure-like activity (43 [11%] vs 77 [7%], p=0·011). Symptom frequencies and patterns differed significantly by sex. Among men, chest pain (odds ratio [OR] 2·2, 95% CI 1·6-3·0), dyspnoea (2·2, 1·6-3·0), and diaphoresis (1·7, 1·1-2·7) were significantly associated with sudden cardiac arrest, whereas among women, only dyspnoea was significantly associated with sudden cardiac arrest (2·9, 1·9-4·3). 427 patients with sudden cardiac arrest (mean age 62·2 [SD 13·5]; 122 women and 305 men) were included in the analysis for the replication population and 1238 patients (mean age 59·3 [16·5] years; 689 women, 548 men, and one participant missing data for sex) were included in the control group. Findings were mostly consistent in the replication population; however, notable differences included that, among men, diaphoresis was not associated with sudden cardiac arrest and chest pain was associated with sudden cardiac arrest only in the sex-stratified multivariable analysis. INTERPRETATION: The prevalence of warning symptoms was sex-specific and differed significantly between patients with sudden cardiac arrest and controls. Warning symptoms hold promise for prediction of imminent sudden cardiac arrest but might need to be augmented with additional features to maximise predictive power. FUNDING: US National Heart Lung and Blood Institute.

A panel of blood biomarkers unique to sudden cardiac arrest.

BACKGROUND: The identification of circulating biomarkers specific for sudden cardiac arrest (SCA) could enhance risk prediction. Of particular interest are biomarkers specific to SCA, independent of coronary artery disease (CAD). OBJECTIVE: The purpose of this study was to identify biomarkers of SCA obtained close to the SCA event. METHODS: Twenty cases (survivors of SCA) and 40 age- and sex-matched controls were compared, with a replication analysis of 29 cases matched to 57 controls. A secondary analysis compared 20 SCA cases to 20 controls with CAD. Blood samples were obtained from SCA survivors at a median of 11 months after the SCA event. Proteins were analyzed on a mass spectrometer using data-independent acquisition; a subset of cytokines were analyzed using immunoassays; and 1153 lipids (13 classes) were analyzed. A false discovery rate P value of <.05 identified associated proteins. RESULTS: Patients had a mean age of 58 years (range 25-87 years), and 70% were male. A total of 26 protein biomarkers associated with SCA when cases were compared with controls, of which 20 differentiated SCA from CAD. The replication analysis identified 8 of 26 biomarkers, of which 6 were not overlapping with CAD. The top identified biological processes involved the extracellular matrix, coagulation cascades, and platelet activation. Lipids in the lysophosphatidylcholine class were implicated in SCA through the CAD pathway. CONCLUSION: We identified a panel of novel blood biomarkers specifically associated with SCA, including several that may be involved outside the CAD pathway. These biomarkers could have mechanistic significance and the potential to enhance clinical prediction of SCA.

Sudden cardiac arrest during the COVID-19 pandemic: A two-year prospective evaluation in a North American community.

BACKGROUND: Early during the coronavirus disease 2019 (COVID-19) pandemic, higher sudden cardiac arrest (SCA) incidence and lower survival rates were reported. However, ongoing effects on SCA during the evolving pandemic have not been evaluated. OBJECTIVE: The purpose of this study was to assess the impact of COVID-19 on SCA during 2 years of the pandemic. METHODS: In a prospective study of Ventura County, California (2020 population 843,843; 44.1% Hispanic), we compared SCA incidence and outcomes during the first 2 years of the COVID-19 pandemic to the prior 4 years. RESULTS: Of 2222 out-of-hospital SCA cases identified, 907 occurred during the pandemic (March 2020 to February 2022) and 1315 occurred prepandemic (March 2016 to February 2020). Overall age-standardized annual SCA incidence increased from 39 per 100,000 (95% confidence [CI] 37-41) prepandemic to 54 per 100,000 (95% CI 50-57; P <.001) during the pandemic. Among Hispanics, incidence increased by 77%, from 38 per 100,000 (95% CI 34-43) to 68 per 100,000 (95% CI 60-76; P <.001). Among non-Hispanics, incidence increased by 26%, from 39 per 100,000 (95% CI 37-42; P <.001) to 50 per 100,000 (95% CI 46-54). SCA incidence rates closely tracked COVID-19 infection rates. During the pandemic, SCA survival was significantly reduced (15% to 10%; P <.001), and Hispanics were less likely than non-Hispanics to receive bystander cardiopulmonary resuscitation (45% vs 55%; P = .005) and to present with shockable rhythm (15% vs 24%; P = .003). CONCLUSION: Overall SCA rates remained consistently higher and survival outcomes consistently lower, with exaggerated effects during COVID infection peaks. This longer evaluation uncovered higher increases in SCA incidence among Hispanics, with worse resuscitation profiles. Potential ethnicity-specific barriers to acute SCA care warrant urgent evaluation and intervention.

Risk Factors for Sudden Cardiac Arrest Among Hispanic or Latino Adults in Southern California: Ventura PRESTO and HCHS/SOL.

Background Out-of-hospital sudden cardiac arrest (SCA) is a leading cause of mortality, making prevention of SCA a public health priority. No studies have evaluated predictors of SCA risk among Hispanic or Latino individuals in the United States. Methods and Results In this case-control study, adult SCA cases ages 18-85 (n=1,468) were ascertained in the ongoing Ventura Prediction of Sudden Death in Multi-Ethnic Communities (PRESTO) study (2015-2021) in Ventura County, California. Control subjects were selected from 3033 Hispanic or Latino participants who completed Visit 2 examinations (2014-2017) at the San Diego site of the HCHS/SOL (Hispanic Community Health Survey/Study of Latinos). We used logistic regression to evaluate the association of clinical factors with SCA. Among Hispanic or Latino SCA cases (n=295) and frequency-matched HCHS/SOL controls (n=590) (70.2% men with mean age 63.4 and 61.2 years, respectively), the following clinical variables were associated with SCA in models adjusted for age, sex, and other clinical variables: chronic kidney disease (odds ratio [OR], 7.3 [95% CI, 3.8-14.3]), heavy drinking (OR, 4.5 [95% CI, 2.3-9.0]), stroke (OR, 3.1 [95% CI, 1.2-8.0]), atrial fibrillation (OR, 3.7 [95% CI, 1.7-7.9]), coronary artery disease (OR, 2.9 [95% CI, 1.5-5.9]), heart failure (OR, 2.5 [95% CI, 1.2-5.1]), and diabetes (OR, 1.5 [95% CI, 1.0-2.3]). Conclusions In this first population-based study, to our knowledge, of SCA risk predictors among Hispanic or Latino adults, chronic kidney disease was the strongest risk factor for SCA, and established cardiovascular disease was also important. Early identification and management of chronic kidney disease may reduce SCA risk among Hispanic or Latino individuals, in addition to prevention and treatment of cardiovascular disease.

Out-of-hospital cardiac arrest with onset witnessed by emergency medical services: Implications for improvement in overall survival.

Out-of-hospital cardiac arrest (OHCA) remains a major public health problem. Even in high-income countries, survival rates have plateaued in the range of ten percent, stimulating an ongoing interest in developing novel approaches to resuscitation. Emergency Medical Services (EMS)-witnessed OHCAs constitute a subgroup of overall OHCA that occur after the arrival of EMS, leading to rapid initiation of resuscitation and significantly improved survival. In this narrative review we summarize and interpret recent developments in knowledge of EMS-witnessed OHCA regarding prevalence, demographics, location, circumstances, survival outcomes and clinical profile. We examine the possibility of informing novel resuscitation approaches and enhancing mechanistic knowledge by studying EMS-witnessed OHCA, with the goal of improving overall survival from OHCA.

Sudden cardiac arrest in patients with schizophrenia: A population-based study of resuscitation outcomes and pre-existing cardiovascular disease.

Objective: Individuals with schizophrenia carry a high burden of cardiovascular disease and elevated rates of sudden cardiac arrest (SCA), but little published data is available regarding survival from SCA in this population. The authors compared cardiovascular disease burden and resuscitation outcomes following SCA in individuals with and without schizophrenia. Methods: Case-control analysis drawn from a prospective community-based study of SCA in a large community. The authors defined cases as having a pre-SCA history of schizophrenia, and controls as individuals with SCA without a history of schizophrenia. SCA cases with schizophrenia were compared to a 1:5 age- and sex-frequency-matched sample of SCA cases without schizophrenia. Results: The 103 SCA schizophrenia cases were as likely as the 515 cases without schizophrenia to have resuscitation attempted (75% vs. 80%; p = 0.24) and had a shorter 911 call mean response time (5.8 min vs. 6.9 min, p < 0.001). However, they were significantly less likely to present with a shockable rhythm (ventricular fibrillation/pulseless ventricular tachycardia 16% vs. 43%, p < 0.001), and less likely to survive to hospital discharge (3% vs. 14%, p = 0.008). Pre-arrest cardiovascular disease burden was similar in patients with and without schizophrenia. Conclusions: Despite comparable resuscitation characteristics and cardiovascular disease burden, patients with schizophrenia had significantly lower rates of SCA survival. The paucity of previous research into this phenomenon warrants further investigation to identify factors that may improve survival.

Prediction of Sudden Cardiac Death Manifesting With Documented Ventricular Fibrillation or Pulseless Ventricular Tachycardia.

OBJECTIVES: This study aimed to develop a novel clinical prediction algorithm for avertable sudden cardiac death. BACKGROUND: Sudden cardiac death manifests as ventricular fibrillation (VF)/ ventricular tachycardia (VT) potentially treatable with defibrillation, or nonshockable rhythms (pulseless electrical activity/asystole) with low likelihood of survival. There are no available clinical risk scores for targeted prediction of VF/VT. METHODS: Subjects with out-of-hospital sudden cardiac arrest presenting with documented VF or pulseless VT (33% of total cases) were ascertained prospectively from the Portland, Oregon, metro area with population ≈1 million residents (n = 1,374, 2002-2019). Comparisons of lifetime clinical records were conducted with a control group (n = 1,600) with ≈70% coronary disease prevalence. Prediction models were constructed from a training dataset using backwards stepwise logistic regression and applied to an internal validation dataset. Receiver operating characteristic curves (C statistic) were used to evaluate model discrimination. External validation was performed in a separate, geographically distinct population (Ventura County, California, population ≈850,000, 2015-2020). RESULTS: A clinical algorithm (VFRisk) constructed with 13 clinical, electrocardiogram, and echocardiographic variables had very good discrimination in the training dataset (C statistic = 0.808; [95% CI: 0.774-0.842]) and was successfully validated in internal (C statistic = 0.776 [95% CI: 0.725-0.827]) and external (C statistic = 0.782 [95% CI: 0.718-0.846]) datasets. The algorithm substantially outperformed the left ventricular ejection fraction (LVEF) ≤35% (C statistic = 0.638) and performed well across the LVEF spectrum. CONCLUSIONS: An algorithm for prediction of sudden cardiac arrest manifesting with VF/VT was successfully constructed using widely available clinical and noninvasive markers. These findings have potential to enhance primary prevention, especially in patients with mid-range or preserved LVEF.

Survivors of Sudden Cardiac Arrest Presenting With Pulseless Electrical Activity: Clinical Substrate, Triggers, Long-Term Prognosis.

BACKGROUND: The proportion of sudden cardiac arrest (SCA) presenting as pulseless electrical activity (PEA) is rising, and survival remains low. The pathophysiology of PEA-SCA is poorly understood, and current clinical practice lacks specific options for the management of survivors. OBJECTIVES: In this study, the authors sought to investigate clinical profile, triggers, and long-term prognosis in survivors of SCA presenting with PEA. METHODS: The community-based Oregon SUDS (Sudden Unexpected Death Study) (since 2002) and Ventura PRESTO (Prediction of Sudden Death in Multi-ethnic Communities) (since 2015) studies prospectively ascertain all out-of-hospital SCAs of likely cardiac etiology. Lifetime clinical history and detailed evaluation of SCA events is available. We evaluated all SCA survivors with PEA as the presenting rhythm. RESULTS: The study population included 201 PEA-SCA survivors. Of these, 97 could be contacted for access to their clinical records. Among the latter, the mean age was 67 ± 17 years and 58 (60%) were male. After in-hospital examinations, 29 events (30%) were associated with acute myocardial infarction, and 5 (5%) had bradyarrhythmias. Among the remaining 63 patients (65%), specific triggers remained undetermined, although 31 (49%) had a previous history of heart failure. Of the 201 overall survivors, 91 (45%) were deceased after a mean follow-up of 4.2 ± 4.0 years. Survivors under the age of 40 years had an excellent long-term prognosis. CONCLUSIONS: Survivors of PEA-SCA are a heterogeneous group with high prevalence of multiple comorbidities, especially heart failure. Surprisingly good long-term survival was observed in young individuals. Acute myocardial infarction as the precipitating event was common, but triggers remained undetermined in the majority. Provision of individualized care to PEA survivors requires a renewed investigative focus on PEA-SCA.

Ethnicity-Specific Effects on Cardiac Arrest During the COVID-19 Pandemic: A Two-Year Prospective Evaluation in a North American Community.

Background: Out-of-hospital sudden cardiac arrest (SCA) is a major public health problem with mortality >90%, and incidence has increased during the COVID-19 pandemic. Information regarding ethnicity-specific effects on SCA incidence and survival is lacking. Methods: In a prospective, population-based study of Ventura County, CA residents (2020 Pop. 843,843; 44.1% Hispanic), we compared SCA incidence and outcomes during the first two years of the COVID-19 pandemic to the prior four years, overall and by ethnicity (Hispanic vs non-Hispanic). Findings: Of 2,222 OHCA cases identified, 907 occurred during the pandemic (March 2020 - Feb 2022) and 1315 occurred pre-pandemic (March 2016 - Feb 2020). Overall age-standardized annual SCA incidence increased from 38.9/100,000 [95% CI 36.8-41.0] pre-pandemic to 53.8/100,00 [95% CI 50.3 - 57.3, p<0.001] during the pandemic. Among Hispanics, incidence increased by 77%, from 38.2/100,00 [95% CI 33.8-42.5] to 67.7/100,00 [95% CI 59.5- 75.8, p<0.001]. Among non-Hispanics, incidence increased by 26% from 39.4/100,000 [95% CI 36.9-41.9, p<0.001] to 49.8/100,00 [95% CI 45.8-53.8]. SCA incidence rates closely tracked COVID-19 infection rates. During the pandemic, SCA survival was significantly reduced (15.3% to 10.0%, p<0.001) and Hispanics were less likely than non-Hispanics to have bystander CPR (44.6% vs. 54.7%, p=0.005) and shockable rhythm (15.3% vs. 24.1%, p=0.003). Interpretation: Hispanic residents experienced higher SCA rates during the pandemic with less favorable resuscitation profiles. These findings implicate potential ethnicity-specific barriers to acute care and represent an urgent call to action at the community and health-system levels. Funding: National Heart Lung and Blood Institute Grants R01HL145675 and R01HL147358.

Ondansetron is safe and effective for prehospital treatment of nausea and vomiting by paramedics.

UNLABELLED: OBJCTIVE: The objectives were to evaluate the safety and efficacy of ondansetron in the out-of-hospital treatment of undifferentiated nausea or vomiting. METHODS: Patients with severe nausea or intractable vomiting who were transported by paramedic-staffed ambulances in eight California counties were treated with intravenous (IV), intramuscular (IM), or oral dissolving tablet (ODT) administration of ondansetron. Data were collected prospectively for a six-month period using an online database. Prospectively defined outcome measures were 1) efficacy as measured by a quantitative visual analog nausea scale and 2) incidence of adverse effects. There were no control or placebo groups. RESULTS: Data was collected for 2072 patients, but one patient did not receive the medication. Therefore, Ondansetron was administered to 2,071 patients (3.7% of transported patients). Most patients were adult, with only 66 patients less than 18 years old. Of the 2,071 patients, 1,320 (64%) received IV administration, 77 (4%) received IM administration, and 674 (33%) received ODT administration of ondansetron. Intravenous administration resulted in the largest improvements in nausea scores (mean 4.4; 95% confidence interval [CI] 4.2, 4.5), followed by IM (mean 3.6; 95% CI 3.0, 4.3) and ODT (mean 3.3; 95% CI 3.1, 3.5). Overall, the mean decrease in nausea score was 4.0 (95% CI 3.9, 4.1; p < 0.001) on a 10-point scale. After medication administration, four patients had mild hypotension, one had hypertension, two had itching or rash, and one had a brief episode of supraventricular tachycardia that resolved spontaneously. CONCLUSIONS: Ondansetron is safe and effective for out-of-hospital treatment of nausea and vomiting when administered by paramedics via the IV, IM, or oral route. When available to paramedics, ondansetron is used frequently.

Out-of-Hospital Cardiac Arrest Response and Outcomes During the COVID-19 Pandemic.

OBJECTIVES: The purpose of this study was to evaluate the potential impact of the coronavirus disease-2019 (COVID-19) pandemic on out-of-hospital cardiac arrest (OHCA) responses and outcomes in 2 U.S. communities with relatively low infection rates. BACKGROUND: Studies in areas with high COVID-19 infection rates indicate that the pandemic has had direct and indirect effects on community responses to OHCA and negative impacts on survival. Data from areas with lower infection rates are lacking. METHODS: Cases of OHCA in Multnomah County, Oregon, and Ventura County, California, with attempted resuscitation by emergency medical services (EMS) from March 1 to May 31, 2020, and from March 1 to May 31, 2019, were evaluated. RESULTS: In a comparison of 231 OHCA in 2019 to 278 in 2020, the proportion of cases receiving bystander cardiopulmonary resuscitation (CPR) was lower in 2020 (61% to 51%, respectively; p = 0.02), and bystander use of automated external defibrillators (AEDs) declined (5% to 1%, respectively; p = 0.02). EMS response time increased (6.6 ± 2.0 min to 7.6 ± 3.0 min, respectively; p < 0.001), and fewer OHCA cases survived to hospital discharge (14.7% to 7.9%, respectively; p = 0.02). Incidence rates did not change significantly (p > 0.07), and coronavirus infection rates were low (Multnomah County, 143/100,000; Ventura County, 127/100,000 as of May 31) compared to rates of ∼1,600 to 3,000/100,000 in the New York City region at that time. CONCLUSIONS: The community response to OHCA was altered from March to May 2020, with less bystander CPR, delays in EMS response time, and reduced survival from OHCA. These results highlight the pandemic's indirect negative impact on OHCA, even in communities with relatively low incidence of COVID-19 infection, and point to potential opportunities for countering the impact.

Evaluation of Sudden Cardiac Arrest by Race/Ethnicity Among Residents of Ventura County, California, 2015-2020.

Importance: Sudden cardiac arrest (SCA) is a major public health problem. Owing to a lack of population-based studies in multiracial/multiethnic communities, little information is available regarding race/ethnicity-specific epidemiologic factors of SCA. Objective: To evaluate the association of race/ethnicity with burden, outcomes, and clinical profile of individuals experiencing SCA. Design, Setting, and Participants: A 5-year prospective, population-based cohort study of out-of-hospital SCA was conducted from February 1, 2015, to January 31, 2020, among residents of Ventura County, California (2018 population, 848 112: non-Hispanic White [White], 45.8%; Hispanic/Latino [Hispanic], 42.4%; Asian, 7.3%; and Black, 1.7% individuals). All individuals with out-of-hospital SCA of likely cardiac cause and resuscitation attempted by emergency medical services were included. Exposures: Data on circumstances and outcomes of SCA from prehospital emergency medical services records and data on demographics and pre-SCA clinical history from detailed archived medical records, death certificates, and autopsies. Main Outcomes and Measures: Annual age-adjusted SCA incidence by race and ethnicity and SCA circumstances and outcomes by ethnicity. Clinical profile (cardiovascular risk factors, comorbidity burden, and cardiac history) by ethnicity, overall, and stratified by sex. Results: A total of 1624 patients with SCA were identified (1059 [65.2%] men; mean [SD] age, 70.9 [16.1] years). Race/ethnicity data were available for 1542 (95.0%) individuals, of whom 1022 (66.3%) were White, 381 (24.7%) were Hispanic, 86 (5.6%) were Asian, 31 (2.0%) were Black, and 22 (1.4%) were other race/ethnicity. Annual age-adjusted SCA rates per 100 000 residents of Ventura County were similar in White (37.5; 95% CI, 35.2-39.9), Hispanic (37.6; 95% CI, 33.7-41.5; P = .97 vs White), and Black (48.0; 95% CI, 30.8-65.2; P = .18 vs White) individuals, and lower in the Asian population (25.5; 95% CI, 20.1-30.9; P = .006 vs White). Survival to hospital discharge following SCA was similar in the Asian (11.8%), Hispanic (13.9%), and non-Hispanic White (13.0%) (P = .69) populations. Compared with White individuals, Hispanic and Asian individuals were more likely to have hypertension (White, 614 [76.3%]; Hispanic, 239 [79.1%]; Asian, 57 [89.1%]), diabetes (White, 287 [35.7%]; Hispanic, 178 [58.9%]; Asian, 37 [57.8%]), and chronic kidney disease (White, 231 [29.0%]; Hispanic, 123 [40.7%]; Asian, 33 [51.6%]) before SCA. Hispanic individuals were also more likely than White individuals to have hyperlipidemia (White, 380 [47.2%]; Hispanic, 165 [54.6%]) and history of stroke (White, 107 [13.3%]; Hispanic, 55 [18.2%]), but less likely to have a history of atrial fibrillation (White, 251 [31.2%]; Hispanic, 59 [19.5%]). Conclusions and Relevance: The results of this study suggest that the burden of SCA was similar in Hispanic and White individuals and lower in Asian individuals. The Asian and Hispanic populations had shared SCA risk factors, which were different from those of the White population. These findings underscore the need for an improved understanding of race/ethnicity-specific differences in SCA risk.

Adult Patients with Respiratory Distress: Current Evidence-based Recommendations for Prehospital Care.

INTRODUCTION: We developed evidence-based recommendations for prehospital evaluation and treatment of adult patients with respiratory distress. These recommendations are compared with current protocols used by the 33 local emergency medical services agencies (LEMSA) in California. METHODS: We performed a review of the evidence in the prehospital treatment of adult patients with respiratory distress. The quality of evidence was rated and used to form guidelines. We then compared the respiratory distress protocols of each of the 33 LEMSAs for consistency with these recommendations. RESULTS: PICO (population/problem, intervention, control group, outcome) questions investigated were treatment with oxygen, albuterol, ipratropium, steroids, nitroglycerin, furosemide, and non-invasive ventilation. Literature review revealed that oxygen titration to no more than 94-96% for most acutely ill medical patients and to 88-92% in patients with acute chronic obstructive pulmonary disease (COPD) exacerbation is associated with decreased mortality. In patients with bronchospastic disease, the data shows improved symptoms and peak flow rates after the administration of albuterol. There is limited data regarding prehospital use of ipratropium, and the benefit is less clear. The literature supports the use of systemic steroids in those with asthma and COPD to improve symptoms and decrease hospital admissions. There is weak evidence to support the use of nitrates in critically ill, hypertensive patients with acute pulmonary edema (APE) and moderate evidence that furosemide may be harmful if administered prehospital to patients with suspected APE. Non-invasive positive pressure ventilation (NIPPV) is shown in the literature to be safe and effective in the treatment of respiratory distress due to acute pulmonary edema, bronchospasm, and other conditions. It decreases both mortality and the need for intubation. Albuterol, nitroglycerin, and NIPPV were found in the protocols of every LEMSA. Ipratropium, furosemide, and oxygen titration were found in a proportion of the protocols, and steroids were not prescribed in any LEMSA protocol. CONCLUSION: Prehospital treatment of adult patients with respiratory distress varies widely across California. We present evidence-based recommendations for the prehospital treatment of undifferentiated adult patients with respiratory distress that will assist with standardizing management and may be useful for EMS medical directors when creating and revising protocols.

Altered Mental Status: Current Evidence-based Recommendations for Prehospital Care.

INTRODUCTION: In the United States emergency medical services (EMS) protocols vary widely across jurisdictions. We sought to develop evidence-based recommendations for the prehospital evaluation and treatment of a patient with an acute change in mental status and to compare these recommendations against the current protocols used by the 33 EMS agencies in the State of California. METHODS: We performed a literature review of the current evidence in the prehospital treatment of a patient with altered mental status (AMS) and augmented this review with guidelines from various national and international societies to create our evidence-based recommendations. We then compared the AMS protocols of each of the 33 EMS agencies for consistency with these recommendations. The specific protocol components that we analyzed were patient assessment, point-of-care tests, supplemental oxygen, use of standardized scoring, evaluating for causes of AMS, blood glucose evaluation, toxicological treatment, and pediatric evaluation and management. RESULTS: Protocols across 33 EMS agencies in California varied widely. All protocols call for a blood glucose check, 21 (64%) suggest treating adults at <60mg/dL, and half allow for the use of dextrose 10%. All the protocols recommend naloxone for signs of opioid overdose, but only 13 (39%) give specific parameters. Half the agencies (52%) recommend considering other toxicological causes of AMS, often by using the mnemonic AEIOU TIPS. Eight (24%) recommend a 12-lead electrocardiogram; others simply suggest cardiac monitoring. Fourteen (42%) advise supplemental oxygen as needed; only seven (21%) give specific parameters. In terms of considering various etiologies of AMS, 25 (76%) give instructions to consider trauma, 20 (61%) to consider stroke, and 18 (55%) to consider seizure. Twenty-three (70%) of the agencies have separate pediatric AMS protocols; others include pediatric considerations within the adult protocol. CONCLUSION: Protocols for patients with AMS vary widely across the State of California. The evidence-based recommendations that we present for the prehospital diagnosis and treatment of this condition may be useful for EMS medical directors tasked with creating and revising these protocols.

Prehospital Care for the Adult and Pediatric Seizure Patient: Current Evidence-based Recommendations.

INTRODUCTION: We sought to develop evidence-based recommendations for the prehospital evaluation and treatment of adult and pediatric patients with a seizure and to compare these recommendations against the current protocol used by the 33 emergency medical services (EMS) agencies in California. METHODS: We performed a review of the evidence in the prehospital treatment of patients with a seizure, and then compared the seizure protocols of each of the 33 EMS agencies for consistency with these recommendations. We analyzed the type and route of medication administered, number of additional rescue doses permitted, and requirements for glucose testing prior to medication. The treatment for eclampsia and seizures in pediatric patients were analyzed separately. RESULTS: Protocols across EMS Agencies in California varied widely. We identified multiple drugs, dosages, routes of administration, re-dosing instructions, and requirement for blood glucose testing prior to medication delivery. Blood glucose testing prior to benzodiazepine administration is required by 61% (20/33) of agencies for adult patients and 76% (25/33) for pediatric patients. All agencies have protocols for giving intramuscular benzodiazepines and 76% (25/33) have protocols for intranasal benzodiazepines. Intramuscular midazolam dosages ranged from 2 to 10 mg per single adult dose, 2 to 8 mg per single pediatric dose, and 0.1 to 0.2 mg/kg as a weight-based dose. Intranasal midazolam dosages ranged from 2 to 10 mg per single adult or pediatric dose, and 0.1 to 0.2 mg/kg as a weight-based dose. Intravenous/intrasosseous midazolam dosages ranged from 1 to 6 mg per single adult dose, 1 to 5 mg per single pediatric dose, and 0.05 to 0.1 mg/kg as a weight-based dose. Eclampsia is specifically addressed by 85% (28/33) of agencies. Forty-two percent (14/33) have a protocol for administering magnesium sulfate, with intravenous dosages ranging from 2 to 6 mg, and 58% (19/33) allow benzodiazepines to be administered. CONCLUSION: Protocols for a patient with a seizure, including eclampsia and febrile seizures, vary widely across California. These recommendations for the prehospital diagnosis and treatment of seizures may be useful for EMS medical directors tasked with creating and revising these protocols.