Out-of-hospital Cardiac Arrest Cases Research Articles

Cerebral Oximetry during Out-of-Hospital Resuscitation: Pilot Study of First Responder Implementation

Background: Anoxic brain injury is a common mode of death following out-of-hospital cardiac arrest (OHCA). We assessed the course of regional cerebral oxygen saturation (rSO2) at the outset and during first responder resuscitation to understand its relationship with return of spontaneous circulation (ROSC) and functional survival. Methods: We undertook a prospective observational investigation of adult OHCA patients treated by a first-responder EMS agency in King County, WA. Cerebral oximetry was performed using the SenSmart® Model X-100 Universal Oximetry System (Nonin Medical, Inc). We determined cerebral oximetry rSO2 overall and stratified according to ROSC and favorable survival status defined by Cerebral Performance Category (CPC) of 1–2. Results: Among the 59 OHCA cases enrolled, 47% (n = 28) achieved ROSC and 14% (n = 8) survived with CPC 1–2. On average, initial rSO2 cerebral oximetry was 41% and was not different at the outset according to return of spontaneous circulation (ROSC) or survival status. Within 5 minutes of first responder resuscitation, those who would subsequently achieve ROSC had a higher rSO2 than those who would not achieve ROSC (51% vs. 43%, p = 0.03). Among patients who achieved ROSC, those who would survive with CPC 1–2 had a higher rSO2 cerebral oximetry following ROSC than nonsurvivors (74% vs. 60%, p = 0.04 at 5 minutes post ROSC), a difference that was not evident in the minutes prior to ROSC (55% vs. 51% at 3 minutes prior to ROSC, p = 0.5). Conclusion: In this observational study, where first responders applied cerebral oximetry, higher rSO2 during the course of care predicted ROSC among all patients and predicted favorable survival among those who achieved ROSC. Future investigation should evaluate whether and how treatments might modify rSO2 and in turn may influence prognosis.

Effect of Advanced Airway Management by Paramedics During Out-of-Hospital Cardiac Arrest on Chest Compression Fraction and Return of Spontaneous Circulation.

PurposeTo obtain effective systemic blood flow and coronary perfusion by chest compressions during cardiopulmonary resuscitation, it is recommended that the interruption time of chest compressions be kept to a minimum, and that the chest compression fraction (CCF) should be kept high. In this study, we examined the effects of advanced airway management by paramedics in out-of-hospital cardiac arrest (OHCA) cases on CCF and on return of spontaneous circulation (ROSC) before arrival at the hospital.Participants and MethodsA total of 283 adult, non-traumatic OHCA cases who were in cardiopulmonary arrest at the time of EMS contact between April 2015 and March 2017 were registered for this study. We retrospectively investigated the presence or absence of advanced airway clearance, CCF and ROSC during CPR. CCF was calculated by measuring the chest compression interruption time from the ECG waveform recorded on a semiautomatic defibrillator (Philips HeartStart MRX). The data obtained were recorded on a computer, and comparisons between groups were examined using an untested t-test and χ2- test.ResultsOf the 283 patients with OHCA, 159 were included in the analysis. The CCF of the AAM group was 89.4%, which was significantly higher than that in the BMV group (84.3%) (P<0.01). Forty-one patients had ROSC at the time of arrival at the hospital, and the CCF of ROSC patients was 89.7%, which was significantly higher than that of non-ROSC patients (87.2%) (P<0.01). ROSC was also obtained in 31.8% of the patients in the AAM group, which was significantly higher than that in the BMV group (12.2%).ConclusionIn this study, we found that advanced airway management during prehospital emergency transport by paramedics showed high CCF and ROSC rates and contributed to improving the prognosis of OHCA patients through high-quality resuscitation.

Modeling uncertain task compliance in dispatch of volunteers to out-of-hospital cardiac arrest patients

In countries such as Sweden, Italy, Switzerland, and the Netherlands, projects in which volunteers are dispatched to out-of-hospital cardiac arrest (OHCA) patients with the use of mobile phones exist. Once an OHCA case is reported, a notification is sent to the mobile phones of registered volunteers that are in the vicinity of the patient. These projects mostly use static dispatch methods to determine which volunteers should be sent directly to the patient and which ones should pick up an automatic external defibrillator (AED). However, such schemes do not consider uncertainties associated with these task assignment decisions (e.g., if volunteers will do as instructed, or do something else). In this paper, we propose a method for optimized task assignment and dispatch of volunteers to OHCA patients that considers the uncertainty related to volunteers’ actions once assigned a task. We then compare the results of our method to those of a static dispatch method used in an ongoing mobile phone volunteer dispatch project in Sweden and validate them using simulation. Furthermore, we perform a sensitivity analysis on several parameters to investigate their effect on the performance of the proposed method. With the comparative results we show that the proposed method may help increase the survivability of OHCA patients.

Ambient air pollution and out-of-hospital cardiac arrest. Israel nation wide assessment

IntroductionPrevious research suggested that an out-of-hospital cardiac arrest (OHCA) may be triggered by an exposure to ambient pollutants. ObjectiveWe investigated the link between OHCA and a short-term exposure to particulate matter (PM) and other pollutants, within extreme climate conditions in Israel and high PM. MethodsIn a case-crossover analysis, we analyzed all adult cases of OHCA in Israel during 2016–2017. The air-pollution and meteorology data were retrieved from the 132 monitoring stations. All associations at study were investigated using a lag-distributed regression and adjusted to temperature and humidity. ResultsThere were 12401 OHCA cases. Patients experiencing OHCA were likely to be exposed to elevated levels of pollutants, specifically, nitrogen dioxide (NO2) and particulate matter of size ≤2.5 μm (PM2.5) several hours prior to an event, although both at borderline significance, i.e. odds ratio (OR) = 1.20 (95%CI 0.96; 1.51) and OR = 1.15 (95%CI 0.84; 1.60), respectively. An exposure to NO2 was independently associated with OHCA among males (OR = 1.39, 95%CI 0.96; 2.01) and if occurred during the midweek (OR = 1.43, 95%CI 1.03; 1.97). The adverse effect of PM10 was more evident during a weekend (OR = 2.36, 95%CI 0.88; 6.28), as opposed to working days (OR = 0.81, 95%CI 0.45; 1.44). Analysis stratified by regions suggested a spatial variability in pollution associated with OHCA. ConclusionsShort-term exposure to high levels of pollution is adversely associated with OHCA independently of meteorological conditions. The magnitude of the effect is modified by patients' demography. Main findingShort-term exposure to high levels of pollution is adversely associated with OHCA. This effect is independent of temperature and humidity.

Resuscitation in Community Healthcare Facilities in Israel.

Background: Out-of-hospital cardiac-arrest (OHCA) is a major public health challenge. Community health care providers (CHP) may play an important role through early identification, basic life support and defibrillation. Few studies have evaluated the incidence and characteristics of OHCAs initially cared for by CHP, most finding improved survival. This study combined CHP treated OHCA case analysis, with assessment of provider resuscitation preparedness. Methods: An analysis of all CHP initiated resuscitations in a large Health Maintenance Organization (HMO) reported over 42 months, coupled with an online survey assessing CHP resuscitation knowledge, experience, training and self-confidence. Results: 22 resuscitations met inclusion criteria. In 21 CHP initiated chest-compressions but in only 8 cases they utilized the clinic’s automated external defibrillator (AED) prior to emergency medical services (EMS) arrival. There were 275 providers surveyed. Of the surveyed providers, 89.4% reported previous basic life support (BLS)/advanced cardiovascular life support (ALS) training, 67.9% within the last three years. Previous resuscitation experience was reported by 72.7%. The lowest scoring knowledge question was on indications for AED application −56.3%. Additionally, 44.4% reported low confidence in their resuscitation skills. CHP with previous cardiopulmonary resuscitation (CPR) experience reported higher confidence. Longer time since last CPR training lowered self-confidence. Conclusions: Early AED application is crucial for patients with OHCA. All clinics in our study were equipped with AED’s and most CHP received training in their use, but remained insecure regarding their use, often failing to do so.

The impact of ventricular fibrillation amplitude on successful cardioversion, resuscitation duration, and survival after out-of-hospital cardiac arrest

Objective: We sought to examine the incidence of low amplitude ventricular fibrillation and its impact on successful cardioversion, duration of resuscitation, and survival to hospital discharge in patients with out-of-hospital cardiac arrest (OHCA). Design: Retrospective analysis from a statewide registry. Setting: Victoria, Australia. Participants: Consecutive initial ventricular fibrillation arrests with an emergency medical service (EMS)-attempted resuscitation between 1 February 2019 and 30 January 2020. Main outcome measures: Survival to hospital discharge, successful cardioversion, and duration of resuscitation. Results: Of the 471 initial ventricular fibrillation arrests, 429 (91.1%) had sufficient electrocardiogram data for review. The median initial and final ventricular fibrillation amplitude did not differ (0.3 mV; interquartile range [IQR], 0.2-0.5 mV). The final pre-shock amplitude was ≤ 0.1 mV (very fine) and ≤ 0.2 mV (fine) in 22.8% and 37.5% of cases respectively. In a multivariable analysis, only the time between emergency call and first defibrillation was associated with a low initial ventricular fibrillation amplitude ≤ 0.2 mV (adjusted odds ratio [aOR], 1.07; 95% CI, 1.02-1.13; P = 0.004). After adjustment for arrest factors, every 0.1 mV increase in final amplitude was independently associated with survival to hospital discharge (aOR, 1.26; 95% CI, 1.14-1.39; P < 0.001) and initial cardioversion success (aOR, 1.19; 95% CI, 1.07-1.32; P = 0.001). The duration of resuscitation also increased by 1.7 minutes (95% CI, 1.03-2.36; P < 0.001) for every 0.1 mV increase in final amplitude. Conclusion: More than one-third of initial ventricular fibrillation OHCA cases were low in amplitude. Comparative international data are needed to better understand how low amplitude ventricular fibrillation rhythms confound the measurement of OHCA interventions and international benchmarks for survival outcomes.

Machine learning model for predicting out-of-hospital cardiac arrests using meteorological and chronological data

ObjectivesTo evaluate a predictive model for robust estimation of daily out-of-hospital cardiac arrest (OHCA) incidence using a suite of machine learning (ML) approaches and high-resolution meteorological and chronological data.MethodsIn this...

Overcoming challenges of establishing a hospital-based out-of-hospital cardiac arrest registry: accuracy of case identification using administrative data and clinical registries

IntroductionComprehensive identification of out-of-hospital cardiac arrest (OHCA) cases for inclusion in registries remains challenging due to the inherent diversity of OHCA aetiology, presentation, and management. The Northern Adelaide Local Health Network (NALHN) OHCA registry identifies OHCAs presenting to NALHN hospitals using existing data sources to monitor in-hospital treatment and survival. This study aimed to investigate the accuracy of hospital-based data sources for identifying OHCA cases treated at hospital. MethodsRetrospective analysis of all OHCAs aged >18 years included in the NALHN OHCA registry between 2011–16. Registry cases are identified from an emergency medical service (EMS) OHCA registry, Emergency Department (ED) and ICD-10 coding datasets, and key-word searches of two in-hospital clinical registries. Sensitivity and positive predictive values (PPV) of each hospital-based data source were analysed with respect to (a) the number of cases expected to be identified by that source, (b) total OHCA. Non-OHCAs yielded by each source were explored and a sub-analysis of ICD-10 codes was performed. ResultsBetween 2011–16, the four hospital-based sources yielded 992 cases, of which 383 were confirmed as OHCA. The ED coding dataset was the most accurate with a sensitivity and PPV of 78%. The ICD-10 coding dataset had good sensitivity but low PPV (33%). The ED coding dataset, combined with the two in-hospital clinical registries, identified 93% of OHCAs. ConclusionsNo single dataset identified all OHCAs presenting to NALHN hospitals. Combined hospital-based data sources provide a valid method of identifying OHCAs treated at hospital that may be adapted to augment EMS-based data.

Seasonal variation in incidence and outcomes of out of hospital cardiac arrest: A retrospective national observational study in the United States.

Out of hospital cardiac arrest (OHCA) remains a leading cause of mortality among adults in the United States. Environmental impact on incidence and outcomes of OHCA has not been fully investigated in recent years. Previous studies showed a possible increase in incidence and mortality in winter season and during seasons with temperature extremes. This study examines seasonal variation in incidence and outcomes of OHCA in the United States.Retrospective study of adult OHCA using the Nationwide Emergency Department Sample was carried out. Monthly incidence rate per 100,000 ED presentations was calculated. Survival rates for each month of admission were examined by hospital region. Multivariate analyses were conducted to determine the effect of the season and month of admission on survival.A total of 122,870 adult OHCA cases presented to emergency departments (EDs) in 2014 and were included. Average incidence of OHCA cases was 147 per 100,000 ED presentations. Overall survival rate in the study population was 5.6% (95% confidence intervals [CI] = 5.4%–5.9%). Patients had an average age of 65.5 (95% CI: 65.3–65.7) years and were mainly men (61.8%). Rates of OHCA presentations were highest during December and January (9.9% and 10.0%) while survival rates were lowest during December (4.6%) and highest in June (6.9%). Regional variation in OHCA outcomes was also noted with highest average survival rate in West (7.8%) and lowest in South (4.3%). After adjusting for confounders including region of hospital, Summer season (Ref: all other seasons), and more specifically month of June (Ref: all other months) were found to be positively associated with survival (OR 1.27, 95% CI [1.07–1.52], P-value = .008) and (OR 1.43, 95% CI [1.08–1.89], P-value = .012 respectively).Incidence and outcomes of out of hospital cardiac arrest presentations to the emergency departments in the United States have seasonal variation. Both incidence and mortality of OHCA increase during colder months, and survival is significantly higher in summer season or in June. Exploring how to use this variation to improve outcomes through refresher training of medical providers or through other mitigation plans is needed.

The influence of air pollution by PM2.5, PM10 and associated heavy metals on the parameters of out-of-hospital cardiac arrest

Out-of-hospital cardiac arrest (OHCA), defined as abrupt cessation of mechanical activity of the heart, is one of the most common causes of death in high-income countries. Cardiac arrest is most often a result of severe cardiovascular disease. New evidence shows that air pollutants such as heavy metals and atmospheric particulate matter have an impact on the pathophysiology of many cardiovascular diseases as well on incidences of OHCA. This retrospective analysis includes all OHCA cases that occurred in central Poland covering the area of 11.711 km2 with the population density of 108 people per square kilometer. Among 2878 EMS-treated OHCA cases between 2013 and 2016, cardiopulmonary resuscitation (CPR) was attempted in 2076 (72%) patients. Concentrations of air pollutants were compared with temperature, humidity and clinical factors affecting the CPR. The study shows seasonal variation of PM 2.5 (p < 0.001), PM 10 (p < 0.001), As (p < 0.001) and Cd (p < 0.001) over the years. Air pollution has a significant effect on the parameters of pre-hospital evaluation in OHCA patients, especially with respect to the content of PM2.5/PM10 and heavy metals. Nickel exposure affects the incidence of initial shockable rhythm (IRR 0.92; p = 0.01) and effectiveness of CPR (IRR 0.94; p = 0.003). Arsenic has an impact on overall mortality (IRR 1.07; p = 0.01) and death upon the arrival of EMS team (IRR 1.15; p < 0.001). Overall mortality was also related to ambient levels of PM10 (IRR 1.004; p < 0.047).

Sulfonylurea antidiabetics are associated with lower risk of out-of-hospital cardiac arrest: Real-world data from a population-based study.

AimsOut‐of‐hospital cardiac arrest (OHCA) mostly results from ventricular tachycardia/ventricular fibrillation (VT/VF), often triggered by acute myocardial infarction (AMI). Sulfonylurea (SU) antidiabetics can block myocardial ATP‐regulated K+ channels (KATP channels), activated during AMI, thereby modulating action potential duration (APD). We studied whether SU drugs impact on OHCA risk, and whether these effects are related to APD changes.MethodsWe conducted a population‐based case–control study in 219 VT/VF‐documented OHCA cases with diabetes and 697 non‐OHCA controls with diabetes. We studied the association of SU drugs (alone or in combination with metformin) with OHCA risk compared to metformin monotherapy, and of individual SU drugs compared to glimepiride, using multivariable logistic regression analysis. We studied the effects of these drugs on APD during simulated ischaemia using patch‐clamp studies in human induced pluripotent stem cell‐derived cardiomyocytes.ResultsCompared to metformin, use of SU drugs alone or in combination with metformin was associated with reduced OHCA risk (ORSUdrugs‐alone 0.6 [95% CI 0.4–0.9], ORSUdrugs + metformin 0.6 [95% CI 0.4–0.9]). We found no differences in OHCA risk between SU drug users who suffered OHCA inside or outside the context of AMI. Reduction of OHCA risk compared to glimepiride was found with gliclazide (ORadj 0.5 [95% CI 0.3–0.9]), but not glibenclamide (ORadj 1.3 [95% CI 0.6–2.7]); for tolbutamide, the association with reduced OHCA risk just failed to reach statistical significance (ORadj 0.6 [95% CI 0.3–1.002]). Glibenclamide attenuated simulated ischaemia‐induced APD shortening, while the other SU drugs had no effect.ConclusionsSU drugs were associated with reduced OHCA risk compared to metformin monotherapy, with gliclazide having a lower risk than glimepiride. The differential effects of SU drugs are not explained by differential effects on APD.

Association between case volume of ambulance stations and clinical outcomes of out-of-hospital cardiac arrest: A nationwide multilevel analysis

ObjectivesThe case volume effects of ambulance stations on the survival of out-of-hospital cardiac arrest (OHCA) patients are uncertain. This study was conducted to evaluate the association between the case volume of ambulance stations and clinical outcomes in OHCAs by the number of emergency medical services (EMS) providers at the scene. MethodsAdult cardiac EMS-treated OHCAs between 2015 and 2018 were enrolled. The main exposure was the annual OHCA case volumes of 204 ambulance stations in Korea, which were categorized into three groups; low-volume (<100), moderate-volume (100–159) and high-volume (≥160). The primary and secondary outcomes were good neurological recovery and survival to discharge. Multilevel multivariable logistic regression analysis was conducted to calculate adjusted odds ratios (AORs). Interaction analysis between the number of EMS providers at the scene and the exposure variable was performed. ResultsA total of 92,534 patients were enrolled. OHCAs in the low-volume group tended to be arrest in a public place or a non-metropolitan area, less prehospital administration of an advanced airway and intravenous management. Significant differences were found the main analysis: AORs (95% CIs) compared to the low-volume group were 1.15 (1.03–1.29) and 1.14 (1.03–1.27) in the high-volume and moderate-volume groups for good neurological recovery and 1.19 (1.07–1.33) and 1.14 (1.04–1.25) in the high-volume and moderate-volume groups for survival to discharge. Significant interaction effects between the number of EMS providers at the scene and case volume on clinical outcomes were found. ConclusionOHCA case volumes of ambulance stations are associated with clinical outcomes after cardiac arrest.

Impact of community initiatives on non-EMS bystander CPR rates in West Yorkshire between 2014 and 2018

AimBystander CPR rates have steadily increased in England between 2014 and 2018. In West Yorkshire, there have been two important developments during this time. We aimed to describe whether postcode districts (PCDs) with more cumulative annual ‘Restart a Heart’ (RSAH) and/or Community First Responder (CFR) scheme activity between 2014 and 2018 were associated with greater improvements in non-EMS bystander CPR rates for out-of-hospital cardiac arrest (OHCA) when compared with PCDs in the same region with lesser or no such historic activity during the same time period. MethodWe collated data from the OHCA Outcomes Registry for all non-EMS witnessed OHCA in West Yorkshire treated by Yorkshire Ambulance Service. We analysed clusters of PCDs with high and low levels of RSAH and CFR activity between 2014 and 2018 using descriptive statistics, and comparisons were made between groups using chi-square and t-test. ResultsThe reported bystander CPR rate for non-EMS witnessed OHCA cases for West Yorkshire rose from 38.4% in 2014 to 69.7% in 2018. The largest increases were seen in PCDs with high RSAH activity (+34.3%) and in the combination of high RSAH and low CFR activity (+38.5%). There was no significant difference when considering the interaction between RSAH and CFR groups. ConclusionThe data infers the possibility of a non-significant association between improved non-EMS bystander CPR rates and RSAH training and CFR scheme activity. We recommend coordinated mass training, in particular for children in regions where CPR is not a mandatory part of the school curriculum.

Interaction Effect Between Prehospital Mechanical Chest Compression Device Use and Post-Cardiac Arrest Care on Clinical Outcomes After Out-Of-Hospital Cardiac Arrest.

Prehospital application of a mechanical chest compression device (MCD) and post-cardiac arrest (PCA) care including coronary reperfusion therapy (CRT) or targeted temperature management (TTM) could affect the clinical outcome in out-of-hospital cardiac arrest (OHCA). This study aimed to assess whether the effect of PCA care including CRT or TTM differs according to prehospital MCD use in patients with OHCA. Adult OHCA cases with a presumed cardiac etiology and with survival to admission from 2016 to 2017 were enrolled from the Korean nationwide OHCA registry. The main exposures were CRT and TTM during PCA care. The primary outcome was good neurologic recovery defined by a cerebral performance category score of 1 or 2 at hospital discharge. We conducted interaction analyses between MCD use and PCA care including CRT or TTM. Four thousand three hundred sixty-six OHCA cases were enrolled and 7.9% underwent MCD application. TTM and CRT were performed in 11.2% and 17.9% of the study population. In the interaction analysis, the adjusted odds ratios of TTM and CRT for good neurologic recovery were 2.41 (1.90-3.06) and 3.40 (2.79-4.14) in patients without MCD use and 1.89 (0.97-3.68), and 1.54 (0.79-3.01) in patients with MCD use. The effect of PCA care on neurologic outcomes was different according to MCD use in OHCA. The association of good neurologic outcome and PCA care was not observed in the prehospital MCD use group compared with that in the MCD nonuse group.

Outcomes of patients with OHCA of presumed cardiac etiology that did not achieve prehospital restoration of spontaneous circulation: The All-Japan Utstein Registry experience

BackgroundCorrect identification of futile prehospital resuscitation for out-of-hospital cardiac arrest (OHCA) may reduce unnecessary transports. Prehospital return of spontaneous circulation (ROSC) is considered by many to be an important predictor of outcome. The purpose of this study was to evaluate OHCA victims without prehospital ROSC characteristics and their outcomes in relation to the universal Termination of Resuscitation (TOR) rule. MethodsA retrospective, population-based review of OHCA victims without prehospital ROSC from January 1, 2010 to December 31, 2017 in the All-Japan Utstein Registry. We compared those that met the universal TOR rule and those that did not for the primary outcome: one-month survival with neurologically favorable Cerebral Performance Category (CPC) 1 or 2. Results989,929 OHCA cases, 18 years of age or older, were registered in the All-Japan Utstein Registry and 525,801 cases were of presumed cardiac origin and had no prehospital ROSC. Of these, the one-month CPC was 1 or 2 for 3957 cases (0.8%). In the ‘no ROSC’ group who also met the TOR rule, the number of cases was 433,571 with a one-month survival of 0.9% (3799 cases), and the proportion with a CPC 1or 2 was 0.2% (699 cases). ConclusionsContinued resuscitation and transport of cases with no field ROSC who fulfill the TOR rule is futile and could be considered for adoption in Japan.

Outcomes for out-of-hospital cardiac arrest transported to emergency departments in Hanoi, Vietnam: A multi-centre observational study.

To describe the outcomes of patients with out-of-hospital cardiac arrest (OHCA) transported to hospital in Hanoi, Vietnam. This was a multi-centre observational study of patients presenting with OHCA to one of five tertiary care hospital EDs in Hanoi from 2017 to 2019. We analysed data from 239 OHCA cases of which 70.7% were witnessed, and 8.4% received bystander cardiopulmonary resuscitation (CPR). The emergency medical services (EMS) transported 20.5% of cases to hospital with the remaining being transported by private vehicle. No patients received external defibrillation before arriving to hospital. Return of spontaneous circulation in hospital was 33.1%, with 3.8% of patients survived to hospital discharge and only one patient (0.4%) discharged from hospital with a favourable neurological outcome. In cases of OHCA in Hanoi, both the proportion of cases receiving bystander CPR and EMS transportation were small. Urgent investments in pre-hospital capacity, training and capabilities are required to improve outcomes for OHCA in Hanoi.

Out-of-hospital cardiac arrests and mortality in Swiss Cantons with high and low COVID-19 incidence: A nationwide analysis

AimsMany countries reported an increase of out-of-hospital cardiac arrests (OHCAs) and mortality during the COVID-19 pandemic. However, all these data refer to regional settings and national data are still missing. We aimed to assess the OHCA incidence and population mortality during COVID-19 pandemic in whole Switzerland and in the different regions (Cantons) according to the infection rate. MethodsWe considered OHCAs and deaths which occurred in Switzerland after the first diagnosed case of COVID-19 (February 25th) and for the subsequent 65 days and in the same period in 2019. We also compared Cantons with high versus low COVID-19 incidence. ResultsA 2.4% reduction in OHCA cases was observed in Switzerland. The reduction was particularly high (−21.4%) in high-incidence COVID-19 cantons, whilst OHCAs increased by 7.7% in low-incidence COVID-19 cantons. Mortality increased by 8.6% in the entire nation: a 27.8% increase in high-incidence cantons and a slight decrease (−0.7%) in low-incidence cantons was observed. The OHCA occurred more frequently at home, CPR and AED use by bystander were less frequent during the pandemic. Conversely, the OHCAs percentage in which a first responder was present, initiated the CPR and used an AED, increased. The outcome of patients in COVID-19 high-incidence cantons was worse compared to low-incidence cantons. ConclusionsDuring the COVID-19 pandemic in Switzerland mortality increased in Cantons with high-incidence of infection, whilst not in the low-incidence ones. OHCA occurrence followed an opposite trend showing how variables related to the health-system and EMS organization deeply influence OHCA occurrence during a pandemic.

Temporal Trends of Out-of-Hospital Cardiac Arrests Without Resuscitation Attempt by Emergency Medical Services.

Significant improvements in survival from out-of-hospital cardiac arrest (OHCA) have been reported; however, these are based only on data from OHCA in whom resuscitation is initiated by emergency medical services (EMS). We aimed to assess the characteristics and temporal trends of OHCA without resuscitation attempt by EMS. Prospective population-based study between 2011 and 2016 in the Greater Paris area (6.7 million inhabitants). All cases of OHCA were included in collaboration with EMS units, 48 different hospitals, and forensic units. Among 15 207 OHCA (mean age 70.7±16.9 years, 61.6% male), 5486 (36.1%) had no resuscitation attempt by EMS. Factors that were independently associated with increase in likelihood of no resuscitation attempt included: age of patients (odds ratio, 1.06 per year [95% CI, 1.05-1.06], P<0.001), female sex (odds ratio, 1.21 [95% CI, 1.10-1.32], P=0.002), OHCA at home location (odds ratio, 3.38 [95%CI, 2.86-4.01], P<0.001), and absence of bystander (odds ratio, 1.94 [95% CI, 1.74-2.16], P<0.001). Overall, the annual number of OHCA increased by 9.1% (from 2923 to 3189, P=0.028). This increase was related to an increase of the annual number of OHCA without resuscitation attempt by EMS by 26.3% (from 993 to 1253, P=0.012), while the annual number of OHCA with resuscitation attempt by EMS did not significantly change (from 1930 to 1936, P=0.416). Considering only cases with resuscitation attempt, survival rate at hospital discharge increased (from 7.3% to 9.5%, P=0.02). However, when considering all OHCA, survival improvement did not reach statistical significance (from 4.8% to 5.7%, P=0.17). We demonstrated an increase of the total number of OHCA related to an increase of the number of OHCA without resuscitation attempt by EMS. This increasing proportion of OHCA without resuscitation attempt attenuates improvement in survival rates achieved in EMS-treated patients.

Out-of-hospital cardiac arrest treated by emergency medical service teams during COVID-19 pandemic: A retrospective cohort study.

Out-of-hospital cardiac arrest (OHCA) is a challenge for medical personnel, especially in the current COVID-19 pandemic, where medical personnel should perform resuscitation wearing full personal protective equipment. This study aims were to assess the characteristics and outcomes of adults who suffered an OHCA in the COVID-19 pandemic treated by emergency medical service (EMS) teams. All EMS-attended OHCA adults over than 18 years in the Polish EMS registry were analyzed. The retrospective EMS database was conducted. EMS interventions performed between March 1, and April 30, 2020 were retrospectively screened. In the study period EMS operated 527 times for OHCA cases. The average age of patients with OHCA was 67.8 years. Statistically significantly more frequently men were involved (64.3%). 298 (56.6%) of all OHCA patients had resuscitation attempted by EMS providers. Among resuscitated patients, 73.8% were cardiac etiology. 9.4% of patients had return of spontaneous circulation, 27.2% of patients were admitted to hospital with ongoing chest compression. In the case of 63.4% cardiopulmonary resuscitation was ineffective and death was determined. The present study found that OHCA incidence rate in the Masovian population (central region of Poland) in March-April 2020 period was 12.2/100,000 adult inhabitants. Return of spontaneous circulation in EMS was observed only in 9.4% of resuscitated patients. The presence of shockable rhythms was associated with better prognosis. The prehospital mortality, even though it was high, did not differ from those reported by other studies.

Response Time Threshold for Predicting Outcomes of Patients with Out-of-Hospital Cardiac Arrest.

Ambulance response time is a prognostic factor for out-of-hospital cardiac arrest (OHCA), but the impact of ambulance response time under different situations remains unclear. We evaluated the threshold of ambulance response time for predicting survival to hospital discharge for patients with OHCA. A retrospective observational analysis was conducted using the emergency medical service (EMS) database (January 2015 to December 2019). Prehospital factors, underlying diseases, and OHCA outcomes were assessed. Receiver operating characteristic (ROC) curve analysis with Youden Index was performed to calculate optimal cut-off values for ambulance response time that predicted survival to hospital discharge. In all, 6742 cases of adult OHCA were analyzed. After adjustment for confounding factors, age (odds ratio [OR] = 0.983, 95% confidence interval [CI]: 0.975–0.992, p < 0.001), witness (OR = 3.022, 95% CI: 2.014–4.534, p < 0.001), public location (OR = 2.797, 95% CI: 2.062–3.793, p < 0.001), bystander cardiopulmonary resuscitation (CPR, OR = 1.363, 95% CI: 1.009–1.841, p=0.044), EMT-paramedic response (EMT-P, OR = 1.713, 95% CI: 1.282–2.290, p < 0.001), and prehospital defibrillation using an automated external defibrillator ([AED] OR = 3.984, 95% CI: 2.920–5.435, p < 0.001) were statistically and significantly associated with survival to hospital discharge. The cut-off value was 6.2 min. If the location of OHCA was a public place or bystander CPR was provided, the threshold was prolonged to 7.2 min and 6.3 min, respectively. In the absence of a witness, EMT-P, or AED, the threshold was reduced to 4.2, 5, and 5 min, respectively. The adjusted OR of EMS response time for survival to hospital discharge was 1.217 (per minute shorter, CI: 1.140–1299, p < 0.001) and 1.992 (<6.2 min, 95% CI: 1.496–2.653, p < 0.001). The optimal response time threshold for survival to hospital discharge was 6.2 min. In the case of OHCA in public areas or with bystander CPR, the threshold was prolonged, and without witness, the optimal response time threshold was shortened.