A multidisciplinary approach for improving the outcome of out-of-hospital cardiac arrest in South Korea

The SEE-IT Trial: emergency medical services treaming nabled valuation n rauma: study protocol for an interventional feasibility randomised controlled trial

INTRODUCTION

Accurate and timely dispatch of emergency medical services (EMS) is vital due to limited resources and patients' risk of mortality and morbidity increasing with time. Currently, most UK emergency operations centres (EOCs) rely on audio calls and accurate descriptions of the incident and patients' injuries from lay 999 callers. If dispatchers in the EOCs could see the scene via live video streaming from the caller's smartphone, this may enhance their decision making and enable quicker and more accurate dispatch of EMS. The main aim of this feasibility randomised controlled trial (RCT) is to assess the feasibility of conducting a definitive RCT to assess the clinical and cost effectiveness of using live streaming to improve targeting of EMS.

METHODS AND ANALYSIS

The SEE-IT Trial is a feasibility RCT with a nested process evaluation. The study also has two observational substudies: (1) in an EOC that routinely uses live streaming to assess the acceptability and feasibility of live streaming in a diverse inner-city population and (2) in an EOC that does not currently use live streaming to act as a comparator site regarding the psychological well-being of EOC staff using versus not using live streaming.

ETHICS AND DISSEMINATION

The study was approved by the Health Research Authority on 23 March 2022 (ref: 21/LO/0912), which included NHS Confidentiality Advisory Group approval received on 22 March 2022 (ref: 22/CAG/0003). This manuscript refers to V.0.8 of the protocol (7 November 2022). The trial is registered with the ISRCTN (ISRCTN11449333). The first participant was recruited on 18 June 2022.The main output of this feasibility trial will be the knowledge gained to help inform the development of a large multicentre RCT to evaluate the clinical and cost effectiveness of the use of live streaming to aid EMS dispatch for trauma incidents.

TRIAL REGISTRATION NUMBER

ISRCTN11449333.

Analyzing willingness for extracorporeal cardiopulmonary resuscitation in refractory ventricular fibrillation

Extracorporeal cardiopulmonary resuscitation (ECPR) for refractory ventricular fibrillation/ventricular tachycardia in out-of-hospital cardiac arrest has recently been recommended for selected patients with favorable prognostic features. We aimed to identify factors affecting the willingness of emergency physicians to implement extracorporeal cardiopulmonary resuscitation (ECPR). We conducted a factorial survey with nine experimental vignettes by combining three different scene time intervals and transportation time intervals. Emergency physicians reported willingness to implement ECPR (1-100 points). Respondent characteristics that could affect the willingness were studied. Multilevel analysis of vignettes and respondent factors was conducted using a mixed-effects regression model. We obtained 486 vignette responses from 54 emergency physicians. In the case of longer scene time intervals, there was a significant difference in the willingness scores at 9 and 12 min transportation time intervals. When the pre-hospital time interval was > 40 min, emergency physicians demonstrated lower willingness to implement ECPR. Clinical experience of 15-19 years showed a significant favorable effect on willingness to implement extracorporeal membrane oxygenation (ECMO). However, the mean willingness scores of EPs for ECMO implementation were more than 75 across all vignettes. In ECPR, the prehospital time interval is an important factor, and the willingness of emergency physicians to implement ECMO could be mutually affected by scene time intervals, transportation time intervals, and total prehospital time.

Utilization and Effect of Direct Medical Oversight during Out-of-Hospital Cardiac Arrest

STUDY OBJECTIVE

Direct medical oversight (DMO), where emergency medical services (EMS) clinicians contact a physician for real-time medical direction, is used by many EMS systems across the United States. Our objective was to characterize the recommendations made by DMO during out-of-hospital cardiac arrests (OHCA) and to determine their effect on EMS transport decisions and patient outcomes.

METHODS

This is a secondary analysis of DMO call recordings from OHCA cases in the Portland, Oregon metropolitan area from January 1, 2018 to February 28, 2021. Data extracted from the audio recordings were linked to OHCA cases in the Portland Cardiac Arrest Epidemiologic Registry (PDX Epistry). The primary outcomes are recommendations made by DMO: transport, continued field resuscitation, or termination of resuscitation (TOR). Secondary outcomes include EMS transport decisions, survival to hospital admission, and survival to hospital discharge. We used descriptive statistics, unpaired t-tests, and chi-square tests as appropriate for data analysis.

RESULTS

There were 239 OHCA cases for which DMO was contacted by EMS. The median time from EMS arrival to DMO contact was 25.6 min, and EMS requested TOR for 72.0% of patients. Compared to patients where EMS requested further treatment advice, patients for whom EMS requested TOR had poor prognostic signs including older age, asystole as an initial rhythm, and lower rates of transient return of spontaneous circulation prior to DMO call compared with cases where EMS did not request TOR. DMO recommended transport, continued field resuscitation, or TOR in 21.8%, 18.0%, and 60.2% of patients, respectively. Of the 239 patients, 59 (24.7%) were ultimately transported by EMS to the hospital, 14 (5.9%) survived to admission, and only 1 patient (0.4%) survived to hospital discharge and had an acceptable neurologic outcome (Cerebral Performance Category score of 2).

CONCLUSIONS

Patients for whom EMS contacts DMO for further treatment advice or requesting field TOR after prolonged OHCA resuscitation have poor outcomes, even when DMO recommends transport or further resuscitation, and may represent opportunities to reduce unnecessary DMO contact or patient transports. More research is needed to determine which OHCA patients benefit from DMO contact.

Association between Paramedic Workforce and Survival Rate in Prehospital Advanced Life Support in Out-of-Hospital Cardiac Arrest Patients

The low survival rate of out-of-hospital cardiac arrest (OHCA) patients is a global public health challenge. We analyzed the relationship between the number of prehospital EMS personnel and survival admission, survival discharge, and good neurologic outcomes in OHCA patients. This was a retrospective observational study. Adult nontraumatic OHCA patients from January 1, 2015, to December 31, 2018, were included from 12 cities in the Gyeonggi province, a metropolitan area located in the suburbs of the capital of the Republic of Korea. By comparing the insufficient EMS team (four or five EMS personnel) and the sufficient EMS team (six EMS personnel), we showed the survival rate of each group. Using propensity score matching, we reduced the bias of the confounding variables. A total of 3,632 OHCA patients were included. After propensity score matching, survival to admission was higher in the sufficient EMS team than in the insufficient EMS team (odds ratio (OR): 1.38, 95% confidence interval (CI): 1.04–1.84, P=0.03). Survival-to-discharge was similar (OR: 1.70, CI: 1.20–2.40, P=0.03), but there was no significant outcome in good neurologic outcomes (OR: 0.88, CI: 0.57–1.36, P=0.58). Our findings suggest that a sufficient EMS team (six EMS personnel) could improve the survival admission and discharge of OHCA patients compared to an insufficient EMS team (four or five EMS personnel). However, there was no significant difference in neurologic outcomes according to the number of EMS personnel.

Impact of different medical direction policies on prehospital advanced airway management for out-of hospital cardiac arrest patients: A retrospective cohort study

Background

Although optimal prehospital airway management after out-of-hospital cardiac arrest (OHCA) remains undetermined, no studies have compared different advanced airway management (AAM) policies adopted by two hospitals in charge of online medical direction by emergency physicians. We examined the impact of two different AAM policies on OHCA patient survival.

Methods

This observational cohort study included adult OHCA patients treated in Okayama City from 2013 to 2016. Patients were divided into two groups: the O group - those treated on odd days when a hospital with a policy favoring laryngeal tube ventilation (LT) supervised, and the E group - those treated on even days when the other hospital with a policy favoring endotracheal intubation (ETI) supervised. Multiple logistic regression analysis was performed to assess airway device effects. The primary outcome measure was seven-day survival.

Results

Of 2,406 eligible patients, 50.1% were in the O group and 49.9% were in the E group. O group patients received less ETI (1.0% vs. 12.0%) and more LT (53.3% vs. 43.0%) compared with E group patients. In univariate analysis, no differences were observed in seven-day survival (9.4% vs 10.1%). Multiple regression analysis revealed neither LT nor ETI had a significant independent effect on seven-day survival, considering bag-valve mask ventilation as a reference (OR, 0.78; 95% CI, 0.54 to 1.13, OR, 0.79; 95% CI, 0.36 to 1.72, respectively).

Conclusion

Despite different advanced airway medical direction policies in a single city, there were no substantial impact on outcomes for OHCA patients.

Effect of Prehospital Epinephrine on Out-of-Hospital Cardiac Arrest Outcomes: A Propensity Score-Matched Analysis

PURPOSE

A pilot project using epinephrine at the scene under medical control is currently underway in Korea. This study aimed to determine whether prehospital epinephrine administration is associated with improved survival and neurological outcomes in out-of-hospital cardiac arrest (OHCA) patients who received epinephrine during cardiopulmonary resuscitation (CPR) in the emergency department.

MATERIALS AND METHODS

This retrospective observational study used a nationwide multicenter OHCA registry. Patients were classified into two groups according to whether they received epinephrine at the scene or not. The associations between prehospital epinephrine use and outcomes were assessed using propensity score (PS)-matched analysis. Multivariable logistic regression analysis was performed using PS matching. The same analysis was repeated for the subgroup of patients with non-shockable rhythm.

RESULTS

PS matching was performed for 1084 patients in each group. Survival to discharge was significantly decreased in the patients who received prehospital epinephrine [odds ratio (OR) 0.415, 95% confidence interval (CI) 0.250-0.670, p<0.001]. However, no statistical significance was observed for good neurological outcome (OR 0.548, 95% CI 0.258-1.123, p=0.105). For the patient subgroup with non-shockable rhythm, prehospital epinephrine was also associated with lower survival to discharge (OR 0.514, 95% CI 0.306-0.844, p=0.010), but not with neurological outcome (OR 0.709, 95% CI 0.323-1.529, p=0.382).

CONCLUSION

Prehospital epinephrine administration was associated with decreased survival rates in OHCA patients but not statistically associated with neurological outcome in this PS-matched analysis. Further research is required to investigate the reason for the detrimental effect of epinephrine administered at the scene.

Outcomes of Out-of-hospital Cardiac Arrests After a Decade of System-wide Initiatives Optimising Community Chain of Survival in Taipei City

OBJECTIVE

A strengthened chain of survival benefits patient outcomes after out-of-hospital cardiac arrest (OHCA).² Over the past decade, the Taipei Fire Department (TFD) has continuously implemented system-wide initiatives on this issue.We hypothesised that for adult, non-trauma OHCA patients, the bundle of these system-wide initiatives are associated with better outcomes.

METHODS

We conducted a registry-based, retrospective study to examine the association between consecutive system-level initiatives and OHCA survival on a two-yearly basis using trend analysis and multivariable logistic regression. The primary outcome was survival to hospital discharge (STHD) and favourable neurological status.

RESULTS

We analysed 18,076 cases from 2008 to 2017. The numbers of two-yearly cases of OHCA with resuscitation attempts from 2008 to 2017 were 3,576, 3,456, 3,822, 3,811, and 3,411. There was a significant trend of improved STHD (Two-fold) and favourable neurological outcome (Six-fold) over the past decade. Similar trends were observed in the shockable and non-shockable groups. Considering the first 2 years as baseline, the odds of STHD and favourable neurological status in the end of the initiatives increased significantly after adjusting for universally recognised predictors for OHCA survival.

CONCLUSION

For non-trauma adult OHCA in Taipei, continuous, multifaceted system-wide initiatives on the community chain of survival were associated with improved odds of STHD and favourable neurologic outcomes.

A simple method for removing initial irregularity of an electrocardiogram during a transient state of a power supply in a defibrillator

BACKGROUND:

The defibrillator is a device that instantaneously discharges the high energy stored in the capacitor to the human body to help revitalize the heart. The circuit for charging the capacitor uses the same power source as the biosignal measurement unit. Therefore, variation in main power supply voltage, ground noise, and electromagnetic interference from the charging circuit can induce distortion into the biosignal at the initial stage of charging.

OBJECTIVE:

In this study, a simple method is proposed for removing the initial irregularity of an electrocardiogram due to the transient state of a power supply.

METHODS:

To evaluate the method, a 1-channel electrocardiogram measurement unit and peripheral units were separated from the main control module using galvanic isolation. An isolated push-pull converter was designed to power the secondary side. The method was tested under steady-state and transient conditions.

RESULTS:

The obtained results proved that biosignal distortion can be significantly reduced.

CONCLUSION:

This method could be another simple implementation approach for solving signal distortions due to the transient status of power supplies used in medical devices.

Factors Associated with High-Quality Cardiopulmonary Resuscitation Performed by Bystander

Bystander cardiopulmonary dresuscitation (CPR) improves the survival and neurological outcomes of sudden cardiac arrest patients. The rate of bystander CPR is increasing; however, its performance quality has not been evaluated in detail. In this study, emergency medical technicians (EMTs) in the field evaluated bystander CPR quality, and we aimed to investigate the association between bystander information and CPR quality. This retrospective cohort study was based on data included in the Smart Advanced Life Support (SALS) registry between January 2016 and December 2017. We included patients older than 18 years who experienced an out-of-hospital cardiac arrest (OHCA) due to medical causes. Bystander CPR quality was judged to be "high" when the hand positions were appropriate and when compression rates of at least 100/min and compression depths of at least 5 cm were achieved. Among 6,769 eligible patients, 3,799 (58.7%) received bystander CPR, and 6% of bystanders performed high-quality CPR. After adjustment, the occurrence of cardiac arrest at home (adjusted odds ratio (aOR), 95% confidence interval (CI); 0.42, 0.27-0.64), witnessed cardiac arrest (1.45, 1.03-2.06), and younger bystander age all showed associations with one another. High-quality CPR led to a 4.29-fold increase in the chance of neurological recovery. In particular, high-quality CPR in patients aged 60 years showed a significant association compared with other age groups (7.61, 1.41-41.04). The main factor affecting CPR quality in this study was the age of the bystander, and older bystanders found it more difficult to maintain CPR quality. To improve the quality of bystander CPR, training among older bystanders should be the focus.