Early Administration of Adrenaline for Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis

Vasopressin and steroids in addition to adrenaline in cardiac arrest (VAST-A) - A randomised pilot study

BACKGROUND

The potential benefit of combining adrenaline, vasopressin, and corticosteroids in in-hospital cardiac arrest (IHCA) needs to be confirmed in a large clinical trial. This pilot study assesses feasibility and safety of randomising patients to this combination therapy compared to standard care.

MATERIAL AND METHODS

A randomised, double-blind, placebo-controlled pilot study was conducted from December 2022 to June 2024 across three Swedish hospitals (NCT05139849). Witnessed IHCAs meeting criteria for adrenaline were randomised 1:1 to adrenaline, vasopressin, and corticosteroids (intervention) or adrenaline and placebo (control). Primary outcomes included feasibility (e.g., protocol adherence, event times, enrolment rate), and safety. Secondary outcome was return of spontaneous circulation.

RESULTS

Of 183 screened IHCAs, 39 patients (median age 77, 64% male) were randomised (16 intervention, 23 control), with an enrolment rate of 0.8 patients/hospital bed/month. Most cardiac arrests occurred in general wards (n = 17/39, 44%). In the feasibility analysis, four patients at the scene of the arrest and three patients in the intensive care unit experienced protocol deviations. Median time (minutes) from cardiac arrest to rapid response team arrival was similar between groups. Median time to adrenaline administration was 7:00 (IQR 3:00-10:00) (intervention) vs 5:00 (IQR 2:30-8:30) (control) and to vasopressin/placebo 10:30 (IQR 9:30-12:15) vs 9:00 (IQR 5:00-11:00). Return of spontaneous circulation occurred in 38% (6/16) in the intervention group and 17% (4/23) in controls.

CONCLUSION

In this IHCA pilot study, randomisation to adrenaline, vasopressin, and corticosteroids compared to controls was safe, but feasibility needs improvement for adequate enrolment in the VAST-A main study.

External validation of three scores for predicting prehospital return of spontaneous circulation in out-of-hospital cardiac arrest

BACKGROUND

Although three established models for predicting the return of spontaneous circulation (ROSC) in out-of-hospital cardiac arrest (OHCA) exist, combinational external validation of these models remains limited. This study aimed to externally validate and compare the performance of three predictive models-RACA, P-ROSC, and UB-ROSC-and provide evidence to guide the selection and application of predictive models for prehospital ROSC in diverse settings.

METHODS

A retrospective validation was conducted using the National Taiwan University Hospital Hsinchu and Yunlin Branch Out-of-Hospital Cardiac Arrest Research Databases. Patients with EMS-treated OHCAs admitted to the hospital between January 2016 and July 2023 were recruited. The primary outcome was prehospital ROSC. Model performance was evaluated using discrimination, calibration, sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic odds ratio. Calibration and density distribution plots were generated.

RESULTS

All three models demonstrated moderate-to-high discrimination with AUROCs of 0.758 (RACA), 0.755 (P-ROSC), and 0.747 (UB-ROSC). The RACA score exhibited better calibration across the risk deciles, whereas the P-ROSC and UB-ROSC scores tended to overestimate the probabilities at higher predicted risk levels. The P-ROSC score required fewer variables and showed the best separation between prehospital and non-prehospital ROSC cases. Optimal cut-off values for the RACA, P-ROSC, and UB-ROSC scores were 0.45, 41, and - 13, respectively, with corresponding sensitivities of 62 %, 56 %, and 71 % and specificities of 78 %, 82 %, and 69 %. All models achieved high NPVs (>96 %), but PPVs remained low (16-21 %).

CONCLUSIONS

The P-ROSC, which requires fewer variables, has emerged as the most practical model for Taiwanese populations. However, the choice of the model should be guided by the availability of variables, regional EMS characteristics, and trends in prehospital ROSC rates.

Evaluation of the use of intraosseous access on adult patients presenting to the emergency department in urban South Africa

Background

Timely vascular access forms a necessary part of patient management in the Emergency Department (ED). Factors such as hypotension, intravenous drug use, obesity, dark skin, patients at extremes of age, and patients with multiple injuries may make peripheral intravenous cannulation difficult. The intraosseous route remains a suitable alternative for emergency circulatory access. The objectives of this study were to describe the knowledge, attitudes, and practice of doctors in the ED about the use of intraosseous access in critically ill adult patients.

Methods

A descriptive study was performed in the EDs of four hospitals in Gauteng, South Africa. Questionnaires were distributed to doctors working in the ED, including intern medical doctors, community service medical doctors, emergency medicine medical officers, emergency medicine registrars, as well as emergency medicine consultants.

Results

Of 88 participants 64.8 % of participants had never used intraosseous access on adult patients in a resuscitation in the ED. Those who do use intraosseous access, use it 1.5 times a month, per clinician. Reasons for not using intraosseous access included: lack of equipment availability, lack of experience, and other preferable methods.

Conclusion

The advantages of using the intraosseous route for circulatory access include its reliability, ease of teaching, rapid use, and low complication rates. Despite sufficient knowledge of intraosseous access and training received at various courses; provider preference and other systemic barriers, lead to an overall reduction in intraosseous access being used in the clinical setting. Intraosseous access remains a cost-effective, life-saving technique for gaining circulatory access. These results can be used to create awareness regarding the availability of other alternatives for gaining circulatory access, enhancing education and training, and improve the standard of health care, particularly in resource-limited settings.

Cardiac arrest: Pre-hospital strategies to facilitate successful resuscitation and improve recovery rates

The estimated annual incidence of out-of-hospital cardiac arrest (OHCA) is approximately 120 cases per 100000 inhabitants in western countries. Although the rates of bystander cardiopulmonary resuscitation (CPR) and use of automated external defibrillator are increasing, the likelihood of survival to hospital discharge is no more than 8%. To date, various devices and methods have been utilized in the initial CPR approach targeting to improve survival and neurological outcomes in OHCA patients. The aim of this review is to discuss strategies that facilitate resuscitation, increase the chance to achieve return to spontaneous circulation and improve survival to hospital discharge and neurological outcomes in the pre-hospital setting.

Association Between Emergency Medical Services Intervention Volume and Out-of-Hospital Cardiac Arrest Survival: A Propensity Score Matching Analysis

BACKGROUND

Out of hospital cardiac arrest (OHCA) survival rates are very low. An association between institutional OHCA case volume and patient outcomes has been documented. However, whether this applies to prehospital emergency medicine services (EMS) is unknown.

OBJECTIVES

To investigate the association between the volume of interventions by mobile intensive care units (MICU) and outcomes of patients experiencing an OHCA.

METHODS

A retrospective cohort study including adult patients with OHCA managed by medical EMS in five French centers between 2013 and 2020. Two groups were defined depending on the overall annual numbers of MICU interventions: low and high-volume MICU. Primary endpoint was 30-day survival. Secondary endpoints were prehospital return of spontaneous circulation (ROSC), ROSC at hospital admission and favorable neurological outcome. Patients were matched 1:1 using a propensity score. Conditional logistic regression was then used.

RESULTS

2,014 adult patients (69% male, median age 68 [57-79] years) were analyzed, 50.5% (n = 1,017) were managed by low-volume MICU and 49.5% (n = 997) by high-volume MICU. Survival on day 30 was 3.6% in the low-volume group compared to 5.1% in the high-volume group. There was no significant association between MICU volume of intervention and survival on day 30 (OR = 0.92, 95%CI [0.55;1.53]), prehospital ROSC (OR = 1.01[0.78;1.3]), ROSC at hospital admission (OR = 0.92 [0.69;1.21]), or favorable neurologic prognosis on day 30 (OR = 0.92 [0.53;1.62]).

The Impact on Patient Prognosis of Changes to the Method of Notifying Staff About Accepting Patients With Out-of-Hospital Cardiac Arrest

Background

Our hospital is a designated emergency hospital and accepts many patients with out-of-hospital cardiac arrest (OHCA). Previously, after receiving a direct call from emergency services to request acceptance of an OHCA patient, the emergency room (ER) chief nurse notified medical staff. However, this method delayed ER preparations, so a Code Blue system (CB) was introduced in which the pending arrival of an OHCA patient was broadcast throughout the hospital.

Methods

In this study, we retrospectively analyzed the impact of introducing CB at our hospital on OHCA patient prognosis to examine whether the introduction of CB is clinically meaningful. We compared consecutive cases treated before introduction of the CB (March 3, 2022, to March 22, 2023) with those treated afterwards (March 23, 2023, to July 23, 2024).

Results

A total of 30 cases per group were included. The mean number of medical staff present at admissions increased significantly from 5.4 ± 0.6 to 15.0 ± 3.0 (P < 0.001). Although not statistically significant, the introduction of the CB increased the return of spontaneous circulation (ROSC) rate from 20% to 30%, survival to discharge rate from 3% to 10%, and social reintegration rate from 0% to 3%. ROSC occurred in 15 patients. Among OHCA patients with cardiac disease, the ROSC rate tended to increase from 0% to 43% (P = 0.055). In addition, in OHCA patients with cardiac disease whose electrocardiogram initially showed ventricular fibrillation or pulseless electrical activity, the ROSC rate increased from 0% to 100%. ROSC tended to be influenced by the total number of staff and physicians present and the number of staff such as medical clerks, clinical engineers, and radiology technicians (P = 0.095, 0.076, 0.088, respectively).

Conclusions

Introduction of a CB may increase the ROSC rate and the number of patients surviving to discharge. It also appears to improve the quality of medical care by quickly gathering all necessary medical staff so that they can perform their predefined roles.

Optimal weight-based epinephrine dosing for patients with a low likelihood of survival following out-of-hospital cardiac arrest

INTRODUCTION

Cardiac arrest patients presenting with non-shockable rhythms have a low probability of survival, and epinephrine is one of the few pharmaceutical options for this group. The recommended 1.0 mg adult dose is extrapolated from early animal studies and lacks adjustment for patient weight. Although several prior studies have investigated "low-" and "high-" dose epinephrine, none have identified a benefit to either strategy.

AIMS

To identify an optimal weight-based epinephrine dose for return-of-spontaneous-circulation (ROSC) after a single bolus among patients with low likelihood of survival.

METHODS

Included were adult patients who experienced a witnessed, non-traumatic out-of-hospital cardiac arrest prior to EMS arrival. Patients with shockable presenting rhythms or receiving bystander CPR were excluded. The AUROC was used to assess the predictive value of epinephrine dose (mg/kg) for ROSC following a single bolus. From the ROC curve, the optimal threshold dosage (OTD) was determined using the Youden Index. A logistic regression model calculated the adjusted odds ratio of OTD on ROSC.

RESULTS

A total of 2,463 patients met inclusion criteria, of which 190 (7.7%) attained ROSC after the first epinephrine administration. The dosage AUROC for ROSC was 0.603 (p < 0.01). As calculated by the Youden index, the OTD was 0.013 mg/kg. Patients receiving ≥ OTD were more likely to attain ROSC after a single epinephrine bolus (OR = 2.25,p < 0.001).

CONCLUSIONS

Among patients with a low likelihood of survival, the optimal dose of epinephrine for attaining ROSC with a single bolus of epinephrine was 0.013 mg/kg. These findings should inspire further investigation into optimal dosing strategies for epinephrine.

Intraosseous and Intravenous Epinephrine Administration Routes in Out-of-Hospital Cardiac Arrest: Survival and Neurologic Outcomes

BACKGROUND

The rate of survival after out-of-hospital cardiac arrest varies depending on the timeliness and effectiveness of prehospital interventions. This study was conducted to compare out-of-hospital cardiac arrest outcomes between intravenous and intraosseous routes and between upper and lower extremity routes for drug administration.

METHODS AND RESULTS

We retrospectively analyzed data (collected using the Utstein template) from 1220 patients who had experienced out-of-hospital cardiac arrest in Taiwan's Taoyuan City between January 2021 and August 2023. The patients were stratified into intravenous and intraosseous groups by treatment approach and upper and lower extremity access groups by access site. The study outcomes were survival to discharge, favorable neurologic outcomes (Cerebral Performance Category score 1 or 2), and survival for >2 hours. The study groups were statistically compared before and after propensity score matching. Significant pre-propensity score matching differences were observed between intravenous and intraosseous groups, and the aforementioned study outcomes were better in the intravenous group than in the intraosseous group. However, the between-group differences became nonsignificant after propensity score matching. Furthermore, lower extremity access and delayed epinephrine administration were associated with worse outcomes. Survival rates fell below 12.6% when time to treatment exceeded 15 minutes, particularly in the cases of intraosseous access and lower extremity access.

CONCLUSIONS

This study highlights the benefits of early intervention and upper extremity access for drug administration in patients with out-of-hospital cardiac arrest. Intraosseous access may serve as a viable alternative to intravenous access. Timely administration of essential drugs during resuscitation can improve clinical outcomes and thus has implications for emergency medical service training.

Influence of patient body weight on the probability of return of spontaneous circulation following out-of-hospital cardiac arrest: an exploratory analysis

Introduction

In addition to key interventions, including bystander CPR and defibrillation, successful resuscitation of out-of-hospital cardiac arrest (OHCA) is also associated with several patient-level factors, including a shockable presenting rhythm, younger age, Caucasian race and female sex. An additional patient-level factor that may influence outcomes is patient weight, yet this attribute has not been extensively studied within the context of OHCA, despite globally increasing obesity rates.

Objective

To assess the relationship between patient weight and return of spontaneous circulation (ROSC) during OHCA.

Methods

This retrospective study included adult patients from a national emergency medical services (EMS) patient record, with witnessed, non-traumatic OHCA prior to EMS arrival from January to December 2020. Logistic regression was used to evaluate the relationship between patient weight and ROSC.

Results

Complete records were available for 9096 patients, of which 64.3% were males and 25.3% were ethnic minorities. The mean age of the participants was 65.01 years (SD = 15.8), with a mean weight of 93.52 kg (SD = 31.5). Altogether, 81.8% of arrests were of presumed cardiac aetiology and 30.3% presented with a shockable rhythm. Bystander CPR and automated external defibrillator (AED) shock were performed in 30.6% and 7.3% of cases, respectively, and 44.0% experienced ROSC. ROSC was less likely with patient weight >100 kg (OR = 0.709, p <0.001), male sex (OR = 0.782, p <0.001), and increasing age and EMS response time (OR = 0.994 per year, p <0.001 and OR = 0.970 per minute, p <0.001, respectively). Patients with shockable rhythms were more likely to achieve ROSC (OR = 1.790, p <0.001), as were patients receiving bystander CPR (OR = 1.170, p <0.001) and defibrillation prior to EMS arrival (OR = 1.658, p <0.001). Although the mean first adrenaline dose (mg/kg) followed a downward trend due to its non-weight-based dosing scheme, the mean total adrenaline dose administered to achieve ROSC demonstrated an upward linear trend of 0.05 mg for every 5 kg of body weight.

Conclusions

Patient weight was negatively associated with ROSC and positively associated with the total adrenaline dose required to attain ROSC.

Early intramuscular adrenaline administration is associated with improved survival from out-of-hospital cardiac arrest

BACKGROUND

Early administration of adrenaline is associated with improved survival after out-of-hospital cardiac arrest (OHCA). Delays in vascular access may impact the timely delivery of adrenaline. Novel methods for administering adrenaline before vascular access may enhance survival. The objective of this study was to determine whether an initial intramuscular (IM) adrenaline dose followed by standard IV/IO adrenaline is associated with improved survival after OHCA.

METHODS STUDY DESIGN

We conducted a before-and-after study of the implementation of an early, first-dose IM adrenaline EMS protocol for adult OHCAs. The pre-intervention period took place between January 2010 and October 2019. The post-intervention period was between November 2019 and May 2024.

SETTING

Single-center urban, two-tiered EMS agency.

PARTICIPANTS

Adult, nontraumatic OHCA meeting criteria for adrenaline use.

INTERVENTION

Single dose (5 mg) IM adrenaline. All other care, including subsequent IV or IO adrenaline, followed international guidelines.

MAIN OUTCOMES AND MEASURES

The primary outcome was survival to hospital discharge. Secondary outcomes were time from EMS arrival to the first dose of adrenaline, survival to hospital admission, and favorable neurologic function at discharge.

RESULTS

Among 1405 OHCAs, 420 (29.9%) received IM adrenaline and 985 (70.1%) received usual care. Fifty-two patients received the first dose of adrenaline through the IV or IO route within the post-intervention period and were included in the standard care group analysis. Age was younger and bystander CPR was higher in the IM adrenaline group. All other characteristics were similar between IM and standard care cohorts. Time to adrenaline administration was faster for the IM cohort [(median 4.3 min (IQR 3.0-6.0) vs. 7.8 min (IQR 5.8-10.4)]. Compared with standard care, IM adrenaline was associated with improved survival to hospital admission (37.1% vs. 31.6%; aOR 1.37, 95% CI 1.06-1.77), hospital survival (11.0% vs 7.0%; aOR 1.73, 95% CI 1.10-2.71) and favorable neurologic status at hospital discharge (9.8% vs 6.2%; aOR 1.72, 95% CI 1.07-2.76).

CONCLUSION

In this single-center before-and-after implementation study, an initial IM dose of adrenaline as an adjunct to standard care was associated with improved survival to hospital admission, survival to hospital discharge, and functional survival. A randomized controlled trial is needed to fully assess the potential benefit of IM adrenaline delivery in OHCA.

[Quality of life after in-hospital cardiac arrest : An 11-year experience from an university center]

BACKGROUND

Cardiac arrest is a life-threatening condition requiring urgent medical care and is one of the leading causes of death worldwide. Given that in-hospital cardiac arrest (IHCA) is still poorly investigated, data on health-associated quality of life thereafter remains scarce. The available evidence is mostly transferred from out-of-hospital cardiac arrest studies, but the epidemiology and determinants of success might be different. The aim of the study was to investigate the change in the quality of life after in-hospital cardiac arrest and to identify potential risk factors for a poor outcome.

MATERIAL AND METHODS

This retrospective analysis of data and prospective evaluation of quality of life included all patients surviving an IHCA and being treated by the emergency medical team between 2010 and 2020. The primary endpoint of the study was the quality of life after IHCA at the reference date. Secondary endpoints covered determination of risk factors and predictors of poor outcome after in-hospital cardiopulmonary resuscitation.

RESULTS

In total 604 patients were resuscitated within the period of 11 years and 61 (10%) patients survived until the interview took place. Finally, 48 (79%) patients fulfilled the inclusion criteria and 31 (65%) were included in the study. There was no significant difference in the quality of life before and after cardiac arrest (EQ-5D-5L utility 0.79 vs. 0.78, p = 0.567) and in the EQ-5D-5L visual analogue scale (VAS) score.

CONCLUSION

The quality of life before and after IHCA in survivors was good and comparable. The quality of life was mostly affected by reduced mobility and anxiety/depression. Future studies with larger patient samples should focus on potentially modifiable factors that could prevent, warn, and limit the consequences of in-hospital cardiac arrest. Moreover, research on outcomes of IHCA should include available tools for the quality of life assessment.

Association of Advanced Airway Management in Preference to Intravenous Adrenaline on Neurological Outcomes Following Out-of-Hospital Cardiac Arrest

AIM

To examine the preference for advanced airway management (AAM) or intravenous adrenaline administration (IVAd) provided by emergency medical services (EMS) for out-of-hospital cardiac arrest (OHCA) with shockable or nonshockable rhythms.

METHODS

We conducted a retrospective analysis of a nationwide cohort of OHCA patients in Japan. Adult patients with witnessed collapse who were provided AAM and/or IVAd by EMS between June 2014 and December 2019 were divided into the AAM preferred group and IVAd preferred group, according to the initial advanced EMS intervention. The rates of favorable neurological outcomes (cerebral performance category 1 or 2 after 30 days) were compared between groups of patients with initial shockable or nonshockable rhythms.

RESULTS

We analyzed 1365 and 9733 patients with initial shockable and nonshockable rhythms, respectively. Of these patients, 1033 (75.7%) with shockable and 7844 (80.6%) with nonshockable rhythms, respectively, were assigned to the AAM preferred group. Favorable neurological outcomes were significantly more frequent in the AAM preferred group than in the IVAd preferred group in patients with a shockable rhythm (13.6% vs 9.3%, respectively; P = 0.039), but not in those with a nonshockable rhythm (1.0% vs 0.8%, respectively; P = 0.509). Preferred AAM was independently associated with a higher probability of favorable neurological outcomes in patients with a shockable rhythm (adjusted odds ratio 1.66, 95% confidence interval 1.08-2.53, P = 0.020), but not in patients with a nonshockable rhythm.

CONCLUSIONS

AAM provided by EMS in preference to IVAd was associated with the favorable neurological outcomes of OHCA patients with shockable rhythms.

Machine learning-based analysis of regional differences in out-of-hospital cardiopulmonary arrest outcomes and resuscitation interventions in Japan

Refining out-of-hospital cardiopulmonary arrest (OHCA) resuscitation protocols for local emergency practices is vital. The lack of comprehensive evaluation methods for individualized protocols impedes targeted improvements. Thus, we employed machine learning to assess emergency medical service (EMS) records for examining regional disparities in time reduction strategies. In this retrospective study, we examined Japanese EMS records and neurological outcomes from 2015 to 2020 using nationwide data. We included patients aged ≥ 18 years with cardiogenic OHCA and visualized EMS activity time variations across prefectures. A five-layer neural network generated a neurological outcome predictive model that was trained on 80% of the data and tested on the remaining 20%. We evaluated interventions associated with changes in prognosis by simulating these changes after adjusting for time factors, including EMS contact to hospital arrival and initial defibrillation or drug administration. The study encompassed 460,540 patients, with the model's area under the curve and accuracy being 0.96 and 0.95, respectively. Reducing transport time and defibrillation improved outcomes universally, while combining transport time and drug administration showed varied efficacy. In conclusion, the association of emergency activity time with neurological outcomes varied across Japanese prefectures, suggesting the need to set targets for reducing activity time in localized emergency protocols.

A Narrative Review of Drug Therapy in Adult and Pediatric Cardiac Arrest

Drugs are used during cardiopulmonary resuscitation (CPR) in association with chest compressions and ventilation. The main purpose of drugs during resuscitation is either to improve coronary perfusion pressure and myocardial perfusion in order to achieve return of spontaneous circulation (ROSC). The aim of this up-to-date review is to provide an overview of the main drugs used during cardiac arrest (CA), highlighting their historical context, pharmacology, and the data to support them. Epinephrine remains the only recommended vasopressor. Regardless of the controversy about optimal dosage and interval between doses in recent papers, epinephrine should be administered as early as possible to be the most effective in non-shockable rhythms. Despite inconsistent survival outcomes, amiodarone and lidocaine are the only two recommended antiarrhythmics to treat shockable rhythms after defibrillation. Beta-blockers have also been recently evaluated as antiarrhythmic drugs and show promising results but further evaluation is needed. Calcium, sodium bicarbonate, and magnesium are still widely used during resuscitation but have shown no benefit. Available data may even suggest a harmful effect and they are no longer recommended during routine CPR. In experimental studies, sodium nitroprusside showed an increase in survival and favorable neurological outcome when combined with enhanced CPR, but as of today, no clinical data is available. Finally, we review drug administration in pediatric CA. Epinephrine is recommended in pediatric CA and, although they have not shown any improvement in survival or neurological outcome, antiarrhythmic drugs have a 2b recommendation in the current guidelines for shockable rhythms.

Determinants of survival in sudden cardiac arrest manifesting with pulseless electrical activity

OBJECTIVE

The proportion of sudden cardiac arrests (SCA) manifesting with pulseless electrical activity (PEA) has increased significantly, and the survival rate remains lower than ventricular fibrillation (VF). However, a subgroup of PEA-SCA cases does survive and may yield key predictors of improved outcomes when compared to non-survivors. We aimed to identify key predictors of survival from PEA-SCA.

METHODS

Our study sample is drawn from two ongoing community-based, prospective studies of out-of-hospital SCA: Oregon SUDS from the Portland, OR metro area (Pop. approx. 1 million; 2002-2017) and Ventura PRESTO from Ventura County, CA (Pop. approx. 850,000, 2015-2021). For the present sub-study, we included SCA cases with PEA as the presenting rhythm where emergency medical services (EMS) personnel attempted resuscitation.

RESULTS

We identified 1,704 PEA-SCA cases, of which 173 (10.2%) were survivors and 1,531 (89.8%) non-survivors. Patients whose PEA-SCA occurred in a healthcare unit (16.9%) or public location (18.1%) had higher survival than those whose PEA-SCA occurred at home (9.3%) or in a care facility (5.7%). Young age, witness status, PEA-SCA location and pre-existing COPD/asthma were independent predictors of survival. Among witnessed cases the survival rate was 10% even if EMS response time was >10 minutes.

CONCLUSIONS

Key determinants for survival from PEA-SCA were young age, witnessed status, public location and pre-existing COPD/asthma. Survival outcomes in witnessed PEA cases were better than expected, even with delayed EMS response.

Visual assessment of interactions among resuscitation activity factors in out-of-hospital cardiopulmonary arrest using a machine learning model

Aim

The evaluation of the effects of resuscitation activity factors on the outcome of out-of-hospital cardiopulmonary arrest (OHCA) requires consideration of the interactions among these factors. To improve OHCA success rates, this study assessed the prognostic interactions resulting from simultaneously modifying two prehospital factors using a trained machine learning model.

Methods

We enrolled 8274 OHCA patients resuscitated by emergency medical services (EMS) in Nara prefecture, Japan, with a unified activity protocol between January 2010 and December 2018; patients younger than 18 and those with noncardiogenic cardiopulmonary arrest were excluded. Next, a three-layer neural network model was constructed to predict the cerebral performance category score of 1 or 2 at one month based on 24 features of prehospital EMS activity. Using this model, we evaluated the prognostic impact of continuously and simultaneously varying the transport time and the defibrillation or drug-administration time in the test data based on heatmaps.

Results

The average class sensitivity of the prognostic model was more than 0.86, with a full area under the receiver operating characteristics curve of 0.94 (95% confidence interval of 0.92–0.96). By adjusting the two time factors simultaneously, a nonlinear interaction was obtained between the two adjustments, instead of a linear prediction of the outcome.

Conclusion

Modifications to the parameters using a machine-learning-based prognostic model indicated an interaction among the prognostic factors. These findings could be used to evaluate which factors should be prioritized to reduce time in the trained region of machine learning in order to improve EMS activities.

Influence of advanced life support response time on out-of-hospital cardiac arrest patient outcomes in Taipei

Background

The association between out-of-hospital cardiac arrest patient survival and advanced life support response time remained controversial. We aimed to test the hypothesis that for adult, non-traumatic, out-of-hospital cardiac arrest patients, a shorter advanced life support response time is associated with a better chance of survival. We analyzed Utstein-based registry data on adult, non-traumatic, out-of-hospital cardiac arrest patients in Taipei from 2011 to 2015.

Methods

Patients without complete data, witnessed by emergency medical technicians, or with response times of ≥ 15 minutes, were excluded. We used logistic regression with an exposure of advanced life support response time. Primary and secondary outcomes were survival to hospital discharge and favorable neurological outcomes (cerebral performance category ≤ 2), respectively. Subgroup analyses were based on presenting rhythms of out-of-hospital cardiac arrest, bystander cardiopulmonary resuscitation, and witness status.

Results

A total of 4,278 cases were included in the final analysis. The median advanced life support response time was 9 minutes. For every minute delayed in advanced life support response time, the chance of survival to hospital discharge would reduce by 7% and chance of favorable neurological outcome by 9%. Subgroup analysis showed that a longer advanced life support response time was negatively associated with the chance of survival to hospital discharge among out-of-hospital cardiac arrest patients with shockable rhythm and pulse electrical activity groups.

Conclusions

In non-traumatic, adult, out-of-hospital cardiac arrest patients in Taipei, a longer advanced life support response time was associated with declining odds of survival to hospital discharge and favorable neurologic outcomes, especially in patients presenting with shockable rhythm and pulse electrical activity.

Clinical Validation of Cardiac Arrest Hospital Prognosis (CAHP) Score and MIRACLE2 Score to Predict Neurologic Outcomes after Out-of-Hospital Cardiac Arrest

Background. Out-of-hospital cardiac arrest (OHCA) remains a challenge for emergency physicians, given the poor prognosis. In 2020, MIRACLE2, a new and easier to apply score, was established to predict the neurological outcome of OHCA. Objective. The aim of this study is to compare the discrimination of MIRACLE2 score with cardiac arrest hospital prognosis (CAHP) score for OHCA neurologic outcomes. Methods. This retrospective cohort study was conducted between January 2015 and December 2019. Adult patients (>17 years) with cardiac arrest who were brought to the hospital by an emergency medical service crew were included. Deaths due to trauma, burn, drowning, resuscitation not initiated due to pre-ordered “do not resuscitate” orders, and patients who did not achieve return of spontaneous circulation were excluded. Receiver operating characteristic curve analysis with Youden Index was performed to calculate optimal cut-off values for both scores. Results. Overall, 200 adult OHCA cases were analyzed. The threshold of the MIRACLE2 score for favorable neurologic outcomes was 5.5, with an area under the curve (AUC) value of 0.70 (0.61−0.80, p < 0.001); the threshold of the CAHP score was 223.4, with an AUC of 0.77 (0.68−0.86, p < 0.001). On setting the MIRACLE2 score cut-off value, we documented 64.7% sensitivity (95% confidence interval [CI], 56.9−71.9%), 66.7.0% specificity (95% CI, 48.2−82.0%), 90.8% positive predictive value (PPV; 95% CI, 85.6−94.2%), and 27.2% negative predictive value (NPV; 95% CI, 21.4−33.9%). On establishing a CAHP cut-off value, we observed 68.2% sensitivity (95% CI, 60.2−75.5%), 80.6% specificity (95% CI, 62.5−92.6%), 94.6% PPV (95% CI, 88.6%−98.0%), and 33.8% NPV (95% CI, 23.2−45.7%) for unfavorable neurologic outcomes. Conclusions. The CAHP score demonstrated better discrimination than the MIRACLE2 score, affording superior sensitivity, specificity, PPV, and NPV; however, the CAHP score remains relatively difficult to apply. Further studies are warranted to establish scores with better discrimination and ease of application.

Intramuscular adrenaline for out-of-hospital cardiac arrest is associated with faster drug delivery: A feasibility study

BACKGROUND

Early adrenaline administration is associated with return of spontaneous circulation (ROSC) and survival in out-of-hospital cardiac arrest (OHCA). Animal data demonstrate a similar rate of ROSC when early intramuscular (IM) adrenaline is given compared to early intravenous (IV) adrenaline.

AIM

To evaluate the feasibility of protocolized first-dose IM adrenaline in OHCA and it's effect on time from Public Safety Access Point (PSAP) call receipt to adrenaline administration when compared to IO and IV administration.

METHODS

This is a before-and-after feasibility study of adult OHCAs in a single EMS service following adoption of a protocol for first-dose IM adrenaline. Time from PSAP call to administration and outcomes were compared to 674 historical controls (from January 1, 2013-February 8, 2021) who received at least one dose of adrenaline by IV or IO routes.

RESULTS

During the study period, first-dose IM adrenaline was administered to 99 patients (December 1, 2019-February 8, 2021). IM adrenaline was given a median of 12.2 min (95% CI 11.4-13.1 min) after the PSAP call receipt compared to 15.3 min for the IV route (95% CI 14.6-16.0 min) and 15.3 min for the IO route (95% CI 14.9-15.7 min) with a time savings of 3 min (95% CI 2-4 min). Rates of survival to hospital discharge appeared similar between groups: 10% for IM, 8% for IV and 7% for IO. However, results related to survival were underpowered for statistical comparison.

CONCLUSIONS

Within the limitations of a small sample size and before-and-after design, first-dose IM adrenaline was feasible and reduced the time to adrenaline administration.

A Systematic Review and Meta-Analysis of the Implementation of High-Performance Cardiopulmonary Resuscitation on Out-of-Hospital Cardiac Arrest Outcomes

Despite numerous technological and medical advances, out-of-hospital cardiac arrests (OHCAs) still suffer from suboptimal survival rates and poor subsequent neurological and functional outcomes amongst survivors. Multiple studies have investigated the implementation of high-quality prehospital resuscitative efforts, and across these studies, different terms describing high-quality resuscitative efforts have been used, such as high-performance CPR (HP CPR), multi-tiered response (MTR) and minimally interrupted cardiac resuscitation (MICR). There is no universal definition for HP CPR, and dissimilar designs have been employed. This systematic review thus aimed to review current evidence on HP CPR implementation and examine the factors that may influence OHCA outcomes. Eight studies were systematically reviewed, and seven were included in the final meta-analysis. Random-effects meta-analysis found a significantly improved likelihood of prehospital return of spontaneous circulation (pooled odds ratio (OR) = 1.46, 95% CI: 1.16 to 1.82, p < 0.001), survival-to-discharge (pooled OR = 1.32, 95% CI: 1.16 to 1.50, p < 0.001) and favourable neurological outcomes (pooled OR = 1.24, 95% CI: 1.11 to 1.39, p < 0.001) with HP CPR or similar interventions. However, the studies had generally high heterogeneity (I2 greater than 50%) and overall moderate-to-severe risk for bias. Moving forward, a randomised, controlled trial is necessary to shed light on the subject.

Comparative Analysis of the Effectiveness of Performing Advanced Resuscitation Procedures Undertaken by Two- and Three- Person Basic Medical Rescue Teams in Adults under Simulated Conditions

(1) Objective: Paramedics as a profession are a pillar of the State Medical Rescue system. The basic difference between a specialist and a basic team is the composition of members. The aim of the study was to benchmark the effectiveness of performing advanced resuscitation procedures undertaken by two- and three-person basic emergency medical teams in adults under simulated conditions. (2) Design: The research was observational. 200 two- and three-people basic emergency medical teams were analyzed during advanced resuscitation procedures, ALS (Advanced Life Support) in adults under simulated conditions. (3) Method: The study was carried out among professionally active and certified paramedics. It lasted over two years. The study took place under simulated conditions using prepared scenarios. (4) Results: In total, 463 people took part in the study. The analysis of the survey results indicates that the efficiency of three-person teams is superior to the activities performed by two-person teams. Three-person teams were quicker to perform rescue actions than two-person teams. The two-person teams were much quicker to assess the condition of victims than the three-person teams. The three-person teams were more likely to check an open airway. The three-person teams were more efficient in assessing the heart rhythm and current condition of victims. It was demonstrated that three-person teams were more effective during electrotherapy. The analysis demonstrated that three-person teams were significantly faster and more efficient in chest compressions. Three-person teams were less likely to use emergency airway techniques than two-person teams. The results indicate that three-person teams administered the first dose of adrenaline significantly faster than two-person teams. For the “call for help”, the three-person teams were found to be more effective. (5) Conclusion: Paramedics in three-person teams work more effectively, make a proper assessment of heart rhythm and monitor when taking advanced actions. The quality of ventilation and BLS in both groups studied is insufficient. Numerous errors have been observed in two-person teams during pharmacotherapy.

Early Administration of Adrenaline for Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis

Background

The use of adrenaline in out‐of‐hospital cardiac arrest (OHCA) patients is still controversial. This study aimed to determine the effects of early pre‐hospital adrenaline administration in OHCA patients.

Methods and Results

PubMed, EMBASE, Google Scholar, and the Cochrane Library database were searched from study inception to February 2019 to identify studies that reported OHCA patients who received adrenaline. The primary outcome was survival to discharge, and the secondary outcomes were return of spontaneous circulation, favorable neurological outcome, and survival to hospital admission. A total of 574 392 patients were included from 24 studies. The use of early pre‐hospital adrenaline administration in OHCA patients was associated with a significant increase in survival to discharge (risk ratio [RR], 1.62; 95% CI, 1.45–1.83; P<0.001) and return of spontaneous circulation (RR, 1.50; 95% CI, 1.36–1.67; P<0.001), as well as a favorable neurological outcome (RR, 2.09; 95% CI, 1.73–2.52; P<0.001). Patients with shockable rhythm cardiac arrest had a significantly higher rate of survival to discharge (RR, 5.86; 95% CI, 4.25–8.07; P<0.001) and more favorable neurological outcomes (RR, 5.10; 95% CI, 2.90–8.97; P<0.001) than non‐shockable rhythm cardiac arrest patients.

Conclusions

Early pre‐hospital administration of adrenaline to OHCA patients might increase the survival to discharge, return of spontaneous circulation, and favorable neurological outcomes.

Registration

URL: https://www.crd.york.ac.uk/PROSPERO; Unique identifier: CRD42019130542.