Neurologic Recovery at Discharge and Long-Term Survival After Cardiac Arrest.

Importance: Brain injury is the leading cause of death following cardiac arrest and is associated with severe neurologic disabilities among survivors, with profound implications for patients and their families, as well as broader societal impacts. How these disabilities affect long-term survival is largely unknown. Objective: To investigate whether complete neurologic recovery at hospital discharge after cardiac arrest is associated with better long-term survival compared with moderate or severe neurologic disabilities. Design, Setting, and Participants: This cohort study used data from 4 mandatory national registers with structured and predefined data collection and nationwide coverage during a 10-year period in Sweden. Participants included adults who survived in-hospital cardiac arrest (IHCA) or out-of-hospital cardiac arrest (OHCA) beyond 30 days and who underwent predefined neurologic assessment conducted by health care professionals at hospital discharge using the Cerebral Performance Category (CPC) scale between January 2010 and December 2019. Patients were divided into 3 categories: complete recovery (CPC 1), moderate disabilities (CPC 2), and severe disabilities (CPC 3-4). Statistical analyses were performed in December 2023. Exposure: CPC score at hospital discharge. Main Outcomes and Measures: The primary outcome was long-term survival among patients with CPC 1 compared with those with CPC 2 or CPC 3 or 4. Results: A total of 9390 cardiac arrest survivors (median [IQR] age, 69 .0 [58.0-77.0] years; 6544 [69.7%] male) were included. The distribution of functional neurologic outcomes at discharge was 7374 patients (78.5%) with CPC 1, 1358 patients (14.5%) with CPC 2, and 658 patients (7.0%) with CPC 3 or 4. Survival proportions at 5 years were 73.8% (95% CI, 72.5%-75.0%) for patients with CPC 1, compared with 64.7% (95% CI, 62.4%-67.0%) for patients with CPC 2 and 54.2% (95% CI, 50.6%-57.8%) for patients with CPC 3 or 4. Compared with patients with CPC 1, there was significantly higher hazard of death for patients with CPC 2 (adjusted hazard ratio [aHR], 1.57 [95% CI, 1.40-1.75]) or CPC 3 or 4 (aHR, 2.46 [95% CI, 2.13-2.85]). Similar associations were seen in the OHCA and IHCA groups. Conclusions and Relevance: In this cohort study of patients with cardiac arrest who survived beyond 30 days, complete neurologic recovery, defined as CPC 1 at discharge, was associated with better long-term survival compared with neurologic disabilities at the same time point.

Implementation of an extracorporeal resuscitation (ECPR) program for out-of-hospital cardiac arrest in Stockholm, Sweden: Feasibility, safety, and outcome.

Background: The aim of this study was to evaluate the implementation of a novel extra corporeal cardiopulmonary (ECPR) program in the greater Stockholm area with focus on feasibility, safety aspects and clinical outcomes. Methods: Prospective observational study of ECPR program including patients with OHCA from January 2020 to December 2022, fulfilling ECPR criteria: age 18-65 years, initial shockable rhythm or pulseless electrical activity, witnessed arrest, bystander cardiopulmonary resuscitation and refractory arrest after three cycles of advance cardiac life support. The predefined time threshold from collapse to extracorporeal membrane oxygenation (ECMO) initiation was set at 60 min. Results: We included 95 patients. Of these, 22/95 (23%) had return of spontaneous circulation before ECMO initiation, 39/95 (41%) were excluded for ECMO and 34/95 (36%) had ECMO initiated out of which 23 patients were admitted alive to the ICU. ECMO-initiation within 60 min was met in 9%. In 6 patients vascular access was complicated, 2 patients had severe bleeding at access site requiring intervention. Survival to discharge among all cases was 25% (24/95). Among patients admitted to ICU on ECMO 39% (9/23) survived to discharge, of these 78% had cerebral performance category scale score 1-2 within 12 months. 8 out of 9 survivors had time from OHCA to ECMO-initiation >60 min. Conclusion: The implementation of an ECPR protocol was feasible without any major, unexpected safety aspects but did not meet the intended target time intervals. Despite this, survival rates were similar to previous studies although most survivors had >60 min to ECMO-initiation.

Compression-Only or Standard Cardiopulmonary Resuscitation for Trained Laypersons in Out-of-Hospital Cardiac Arrest: A Nationwide Randomized Trial in Sweden.

BACKGROUND: The ongoing TANGO2 (Telephone Assisted CPR. AN evaluation of efficacy amonGst cOmpression only and standard CPR) trial is designed to evaluate whether compression-only cardiopulmonary resuscitation (CPR) by trained laypersons is noninferior to standard CPR in adult out-of-hospital cardiac arrest. This pilot study assesses feasibility, safety, and intermediate clinical outcomes as part of the larger TANGO2 survival trial. METHODS: Emergency medical dispatch calls of suspected out-of-hospital cardiac arrest were screened for inclusion at 18 dispatch centers in Sweden between January 1, 2017, and March 12, 2020. Inclusion criteria were witnessed event, bystander on the scene with previous CPR training, age above 18 years of age, and no signs of trauma, pregnancy, or intoxication. Cases were randomized 1:1 at the dispatch center to either instructions to perform compression-only CPR (intervention) or instructions to perform standard CPR (control). Feasibility included evaluation of inclusion, randomization, and adherence to protocol. Safety measures were time to emergency medical service dispatch CPR instructions, and to start of CPR, intermediate clinical outcome was defined as 1-day survival. RESULTS: Of 11 838 calls of suspected out-of-hospital cardiac arrest screened for inclusion, 2168 were randomized and 1250 (57.7%) were out-of-hospital cardiac arrests treated by the emergency medical service. Of these, 640 were assigned to intervention and 610 to control. Crossover from intervention to control occurred in 16.3% and from control to intervention in 18.5%. The median time from emergency call to ambulance dispatch was 1 minute and 36 s (interquartile range, 1.1-2.2) in the intervention group and 1 minute and 30 s (interquartile range, 1.1-2.2) in the control group. Survival to 1 day was 28.6% versus 28.4% (P=0.984) for intervention and control, respectively. CONCLUSIONS: In this national randomized pilot trial, compression-only CPR versus standard CPR by trained laypersons was feasible. No differences in safety measures or short-term survival were found between the 2 strategies. Efforts to reduce crossover are important and may strengthen the ongoing main trial that will assess differences in long-term survival. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02401633.

The design of the PRINCESS 2 trial: A randomized trial to study the impact of ultrafast hypothermia on complete neurologic recovery after out-of-hospital cardiac arrest with initial shockable rhythm.

BACKGROUND: Delayed hypothermia, initiated after hospital arrival, several hours after cardiac arrest with 8-10 hours to reach the target temperature, is likely to have limited impact on overall survival. However, the effect of ultrafast hypothermia, i.e., delivered intra-arrest or immediately after return of spontaneous circulation (ROSC), on functional neurologic outcome after out-of-hospital cardiac arrest (OHCA) is unclear. In two prior trials, prehospital trans-nasal evaporative intra-arrest cooling was safe, feasible and reduced time to target temperature compared to delayed cooling. Both studies showed trends towards improved neurologic recovery in patients with shockable rhythms. The aim of the PRINCESS2-study is to assess whether cooling, initiated either intra-arrest or immediately after ROSC, followed by in-hospital hypothermia, significantly increases survival with complete neurologic recovery as compared to standard normothermia care, in OHCA patients with shockable rhythms. METHODS/DESIGN: In this investigator-initiated, randomized, controlled trial, the emergency medical services (EMS) will randomize patients at the scene of cardiac arrest to either trans-nasal cooling within 20 minutes from EMS arrival with subsequent hypothermia at 33°C for 24 hours after hospital admission (intervention), or to standard of care with no prehospital or in-hospital cooling (control). Fever (>37,7°C) will be avoided for the first 72 hours in both groups. All patients will receive post resuscitation care and withdrawal of life support procedures according to current guidelines. Primary outcome is survival with complete neurologic recovery at 90 days, defined as modified Rankin scale (mRS) 0-1. Key secondary outcomes include survival to hospital discharge, survival at 90 days and mRS 0-3 at 90 days. In total, 1022 patients are required to detect an absolute difference of 9% (from 45 to 54%) in survival with neurologic recovery (80% power and one-sided α=0,025, ß=0,2) and assuming 2,5% lost to follow-up. Recruitment starts in Q1 2024 and we expect maximum enrolment to be achieved during Q4 2024 at 20-25 European and US sites. DISCUSSION: This trial will assess the impact of ultrafast hypothermia applied on the scene of cardiac arrest, as compared to normothermia, on 90-day survival with complete neurologic recovery in OHCA patients with initial shockable rhythm. TRIAL REGISTRATION: NCT06025123.

Outline and validation of a new dispatcher-assisted cardiopulmonary resuscitation educational bundle using the Delphi method.

Aim: Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) is time-dependent. To date, evidence-based training programmes for dispatchers are lacking. This study aimed to reach expert consensus on an educational bundle content for dispatchers to provide DA-CPR using the Delphi method. Method: An educational bundle was created by the Swedish Resuscitation Council consisting of three parts: e-learning on DA-CPR, basic life support training and audit of emergency out-of-hospital cardiac arrest calls. Thereafter, a two-round modified Delphi study was conducted between November 2022 and March 2023; 37 experts with broad clinical and/or scientific knowledge of DA-CPR were invited. In the first round, the experts participated in the e-learning module and answered a questionnaire with 13 closed and open questions, whereafter the e-learning part of the bundle was revised. In the second round, the revised e-learning part was evaluated using Likert scores (20 items). The predefined consensus level was set at 80%. Results: Delphi rounds one and two were assessed by 20 and 18 of the invited experts, respectively. In round one, 18 experts (18 of 20, 90%) stated that they did not miss any content in the programme. In round two, the scale-level content validity index based on the average method (S-CVI/AVE, 0.99) and scale-level content validity index based on universal agreement (S-CVI/UA, 0.85) exceeded the threshold level of 80%. Conclusion: Expert consensus on the educational bundle content was reached using the Delphi method. Further work is required to evaluate its effect in real-world out-of-hospital cardiac arrest calls.

Neurodevelopmental problems, general health and academic achievements in a school-based cohort of 11-year-old Swedish children.

AIM: Assessing rates of neurodevelopmental problems (NDPs) in 11-year-old children and possible association with other health complaints and school performance. METHODS: In-school study of 11-year-old children as an add-on assessment to the 4th grade regular health check-up, comprising a structured physical neurodevelopmental examination, neuropsychological assessment, behavioural ratings, maternal interview, review of medical records and academic achievements. RESULTS: Out of 348 children recruited from eight schools, 223 (64%) participated. Any physical condition was found in 102/222 (46%), most commonly atopy (18%). One in five had a BMI z-score >2 standard deviations over the reference mean. One or more NDP was found in 86/221 (40%) children. The number of failed national tests correlated positively with NDP severity rated with the clinical global impression severity instrument (Spearman's r = 0.41, p < 0.001). The majority of participants with failed national tests, also had co-occurring health complaints (≥2 of: stomach or extremity ache, headache, difficulties sleeping, internalising symptoms or obesity) and NDPs. CONCLUSION: Health complaints, physical conditions and NDPs are very common in 11-year-old children and warrant adequately staffed, thoroughly equipped school healthcare services.

Transnasal Evaporative Cooling in Out-of-Hospital Cardiac Arrest Patients to Initiate Hypothermia-A Substudy of the Target Temperature Management 2 (TTM2) Randomized Trial.

Background: In animal models, early initiation of therapeutic cooling, intra-arrest, or restored circulation has been shown to be neuroprotective shortly after cardiac arrest. We aimed to assess the feasibility and cooling efficacy of transnasal evaporative cooling, initiated as early as possible after hospital arrival in patients randomized to cooling in the TTM2 trial. Methods: This study took the form of a single-center (Södersjukhuset, Stockholm) substudy of the TTM2 trial (NCT02908308) comparing target temperature management (TTM) to 33 °C versus normothermia in OHCA. In patients randomized to TTM33 °C, transnasal evaporative cooling was applied as fast as possible. The primary objectives were the feasibility aspects of initiating cooling in different hospital locations (i.e., in the emergency department, coronary cathlab, intensive care unit (ICU), and during intrahospital transport) and its effectiveness (i.e., time to reach target temperature). Transnasal cooling was continued for two hours or until patients reached a core temperature of <34 °C. Cooling intervals were compared to participants at the same site who were randomized to hypothermia and treated at 33 °C but who for different reasons did not receive transnasal evaporative cooling. Results: From October 2018 to January 2020, 32 patients were recruited, of which 17 were randomized to the TTM33. Among them, 10 patients (8 men, median age 69 years) received transnasal evaporative cooling prior to surface systemic cooling in the ICU. In three patients, cooling was started in the emergency department; in two patients, it was started in the coronary cathlab, and in five patients, it was started in the ICU, of which three patients were subsequently transported to the coronary cathlab or to perform a CT scan. The median time to initiate transnasal cooling from randomization was 9 min (range: 5 to 39 min). The median time from randomization to a core body temperature of 34 °C was 120 min (range 60 to 334) compared to 178 min among those in the TTM33 group that did not receive TNEC and to 33 °C 230 min (range: 152 to 351) vs. 276 min (range: 150 to 546). No feasibility or technical issues were reported. No adverse events occurred besides minor nosebleeds. Conclusions: The early induction of transnasal cooling in out-of-hospital cardiac arrest patients was feasible to initiate in the emergency department, coronary cathlab, ICU, and during intrahospital transport. Time to target temperature was shortened compared to standard cooling.

Drone delivery of automated external defibrillators compared with ambulance arrival in real-life suspected out-of-hospital cardiac arrests: a prospective observational study in Sweden.

BACKGROUND: A novel approach to improve bystander defibrillation for out-of-hospital cardiac arrests is to dispatch and deliver an automated external defibrillator (AED) directly to the suspected cardiac arrest location by drone. The aim of this study was to investigate how often a drone could deliver an AED before ambulance arrival and to measure the median time benefit achieved by drone deliveries. METHODS: In this prospective observational study, five AED-equipped drones were placed within two separate controlled airspaces in Sweden, covering approximately 200 000 inhabitants. Drones were dispatched in addition to standard emergency medical services for suspected out-of-hospital cardiac arrests and flight was autonomous. Alerts concerning children younger than 8 years, trauma, and emergency medical services-witnessed cases were not included. Exclusion criteria were air traffic control non-approval of flight, unfavourable weather conditions, no-delivery zones, and darkness. Data were collected from the dispatch centres, ambulance organisations, Swedish Registry for Cardiopulmonary Resuscitation, and the drone operator. Core outcomes were the percentage of cases for which an AED was delivered by a drone before ambulance arrival, and the median time difference (minutes and seconds) between AED delivery by drone and ambulance arrival. Explorative outcomes were percentage of attached drone-delivered AEDs before ambulance arrival and the percentage of cases defibrillated by a drone-delivered AED when it was used before ambulance arrival. FINDINGS: During the study period (from April 21, 2021 to May 31, 2022), 211 suspected out-of-hospital cardiac arrest alerts occurred, and in 72 (34%) of those a drone was deployed. Among those, an AED was successfully delivered in 58 (81%) cases, and the major reason for non-delivery was cancellation by dispatch centre because the case was not an out-of-hospital cardiac arrest. In cases for which arrival times for both drone and ambulance were available (n=55), AED delivery by drone occurred before ambulance arrival in 37 cases (67%), with a median time benefit of 3 min and 14 s. Among these cases, 18 (49%) were true out-of-hospital cardiac arrests and a drone-delivered AED was attached in six cases (33%). Two (33%) had a shockable first rhythm and were defibrillated by a drone-delivered AED before ambulance arrival, with one person achieving 30-day survival. No adverse events occurred. AED delivery (not landing) was made within 15 m from the patient or building in 91% of the cases. INTERPRETATION: AED-equipped drones dispatched in cases of suspected out-of-hospital cardiac arrests delivered AEDs before ambulance arrival in two thirds of cases, with a clinically relevant median time benefit of more than 3 min. This intervention could potentially decrease time to attachment of an AED, before ambulance arrival. FUNDING: Swedish Heart Lung Foundation.

Effects of a volunteer responder system for out-of-hospital cardiac arrest in areas of different population density - A retrospective cohort study.

BACKGROUND: Volunteer responder dispatch to nearby out-of-hospital cardiac arrests using a smartphone application can increase the proportion of patients receiving cardiopulmonary resuscitation. It is unknown how population density is related to the efficacy of a volunteer responder system. This study aimed to compare the response time of volunteer responders and EMS dispatched to suspected OHCAs in areas of different population density. METHODS: A total of 2630 suspected OHCAs in Stockholm County during 2018-2020 where at least one dispatched volunteer responder reached the patient were identified through the HeartRunner™ application database. Study outcome was the proportion of cases where volunteer responders arrived at the scene before EMS, as well as the difference in time between the arrival of volunteer responders and EMS. RESULTS: Volunteer responders arrived before EMS in 68% of examined cases (n = 1613). Higher population density was associated with a lower proportion of cases where volunteer responders arrived at the scene before EMS. Time on scene before arrival of EMS was highest in areas of low population density and averaged 4:07 (mm:ss). Response time was significantly shorter for volunteer responders compared to EMS across all population density groups at 4:47 vs 8:11 (mm:ss) (p < 0.001); the largest difference in response time was found in low population density areas. CONCLUSION: Volunteer responders have significantly shorter response time than EMS regardless of population density, with the greatest difference in low population density areas. Although their impact on clinical outcome remains unknown, the benefits of dispatching volunteer responders to OHCAs may be greatest in rural areas.

Swedish emergency medical dispatch centres' ability to answer emergency medical calls and dispatch an ambulance in response to out-of-hospital cardiac arrest calls in accordance with the American Heart Association performance goals: An observational study.

AIM: To investigate the ability of Swedish Emergency Medical Dispatch Centres (EMDCs) to answer medical emergency calls and dispatch an ambulance for out-of-hospital cardiac arrest (OHCA) in accordance with the American Heart Association (AHA) performance goals in a 1-step (call connected directly to the EMDC) and a 2-step (call transferred to regional EMDC) procedure over 10 years, and to assess whether delays may be associated with 30-day survival. METHOD: Observational data from the Swedish Registry for Cardiopulmonary Resuscitation and EMDC. RESULTS: A total of 9,174,940 medical calls were answered (1-step). The median answer delay was 7.3 s (interquartile range [IQR], 3.6-14.5 s). Furthermore, 594,008 calls (6.1%) were transferred in a 2-step procedure, with a median answer delay of 39 s (IQR, 30-53 s). A total of 45,367 cases (0.5%, 1-step) were registered as OHCA, with a median answer delay of 7.2 s (IQR, 3.6-14.1 s) (AHA high-performance goal, 10 s). For 1-step procedure, no difference in 30-day survival was found regarding answer delay. For OHCA (1-step), an ambulance was dispatched after a median of 111.9 s (IQR, 81.7-159.9 s). Thirty-day survival was 10.8% (n = 664) when an ambulance was dispatched within 70 s (AHA high-performance) versus 9.3% (n = 2174) > 100 s (AHA acceptable) (p = 0.0013). Outcome data in the 2-step procedure was unobtainable. CONCLUSION: The majority of calls were answered within the AHA performance goals. When an ambulance was dispatched within the AHA high-performance standard in response to OHCA calls, survival was higher compared with calls when dispatch was delayed.

Dispatch of Volunteer Responders to Out-of-Hospital Cardiac Arrests.

BACKGROUND: Systems for dispatch of volunteer responders to collect automated external defibrillators and/or to provide cardiopulmonary resuscitation (CPR) in cases of nearby out-of-hospital cardiac arrest (OHCA) are widely implemented. OBJECTIVES: This study aimed to investigate whether the activation of a volunteer responder system to OHCAs was associated with higher rates of bystander CPR, bystander defibrillation, and 30-day survival vs no system activation. METHODS: This was a retrospective observational analysis within the ESCAPE-NET (European Sudden Cardiac Arrest network: Towards Prevention, Education, New Effective Treatment) collaborative research network. Included were cases of OHCA between 2015 and 2019 from 5 European sites with volunteer responder systems. At all sites, systems were activated by dispatchers at the emergency medical communication center in response to suspected OHCA. Exposed cases (system activation) were compared with nonexposed cases (no system activation). Risk ratios (RRs) were calculated for the outcomes of bystander CPR, bystander defibrillation, and 30-day survival after inverse probability treatment weighting. Missing data were handled using multiple imputation. RESULTS: In total, 9,553 cases were included. In 4,696 cases, the volunteer responder system was activated, and in 4,857 it was not. The pooled RRs were 1.30 (95% CI: 1.15-1.47) for bystander CPR, 1.89 (95% CI: 1.36-2.63) for bystander defibrillation, and 1.22 (95% CI: 1.07-1.39) for 30-day survival. CONCLUSIONS: Activation of a volunteer response system in cases of OHCA was associated with a higher chance of bystander CPR, bystander defibrillation, and 30-day survival vs no system activation. A randomized controlled trial is necessary to determine fully the causal effect of volunteer responder systems.

Visual and ocular findings in children with fetal alcohol spectrum disorders (FASD): validating the FASD Eye Code in a clinical setting.

OBJECTIVE: Fetal alcohol spectrum disorders (FASD) is an umbrella term covering a spectrum of medical conditions caused by prenatal alcohol exposure. The FASD Eye Code is a new complementary ophthalmological diagnostic tool created to corroborate the complex FASD diagnosis. The aim of this work was to validate the FASD Eye Code by testing it on a second group of children diagnosed with FASD in a clinical setting. METHODS AND ANALYSIS: A clinical study was carried out in a group of 21 children (13 males, 8 females, mean age 13.3 years) investigated for suspected FASD and a healthy sex-matched and age-matched control group (n=21). The participants underwent a detailed ophthalmological examination including visual perception problems (VPPs) assessment. Clinical examination results were compiled, and total scores were calculated according to the FASD Eye Code protocol (range 4-16). RESULTS: The median total score in the FASD group was 8. Eight individuals in the FASD group and none of the controls obtained a total score of ≥9 corresponding to 38% sensitivity and 100% specificity with an area under the curve of 0.90. A cut-off total score of ≥8 showed 52% sensitivity and 95% specificity. One individual in the FASD group versus 12 controls had a total score of 4, representing normal findings. No significant difference between the two groups regarding VPPs was seen. CONCLUSION: The FASD Eye Code can be used as a complementary diagnostic tool for FASD to assist in diagnosis and to detect ophthalmological abnormalities in individuals with suspected FASD.

Effect of Smartphone Dispatch of Volunteer Responders on Automated External Defibrillators and Out-of-Hospital Cardiac Arrests: The SAMBA Randomized Clinical Trial.

Importance: Smartphone dispatch of volunteer responders to nearby out-of-hospital cardiac arrests (OHCAs) has emerged in several emergency medical services, but no randomized clinical trials have evaluated the effect on bystander use of automated external defibrillators (AEDs). Objective: To evaluate if bystander AED use could be increased by smartphone-aided dispatch of lay volunteer responders with instructions to collect nearby AEDs compared with instructions to go directly to patients with OHCAs to start cardiopulmonary resuscitation (CPR). Design, Setting, and Participants: This randomized clinical trial assessed a system for smartphone dispatch of volunteer responders to individuals experiencing OHCAs that was triggered at emergency dispatch centers in response to suspected OHCAs and randomized 1:1. The study was conducted in 2 main Swedish regions: Stockholm and Västra Götaland between December 2018 and January 2020. At study start, there were 3123 AEDs in Stockholm and 3195 in Västra Götaland and 24 493 volunteer responders in Stockholm and 19 117 in Västra Götaland. All OHCAs in which the volunteer responder system was activated by dispatchers were included. Excluded were patients with no OHCAs, those with OHCAs not treated by the emergency medical services, and those with OHCAs witnessed by the emergency medical services. Interventions: Volunteer responders were alerted through the volunteer responder system smartphone application and received map-aided instructions to retrieve nearest available public AEDs on their way to the OHCAs. The control arm included volunteer responders who were instructed to go directly to the OHCAs to perform CPR. Main Outcomes and Measures: Overall bystander AED attachment, including those attached by volunteer responders and lay volunteers who did not use the smartphone application. Results: Volunteer responders were activated for 947 patients with OHCAs. Of those, 461 were randomized to the intervention group (median [IQR] age of patients, 73 [61-81] years; 295 male patients [65.3%]) and 486 were randomized to the control group (median [IQR] age of patients, 73 [63-82] years; 312 male patients [65.3%]). Primary outcome of AED attachment occurred in 61 patients (13.2%) in the intervention arm vs 46 patients (9.5%) in the control arm (difference, 3.8% [95% CI, -0.3% to 7.9%]; P = .08). The majority of AEDs were attached by lay volunteers who were not using the smartphone application (37 in intervention arm, 28 in control). There were no significant differences in secondary outcomes. Among the volunteer responders using the application, crossover was 11% and compliance to instructions was 31%. Volunteer responders attached 38% (41 of 107) of all AEDs and provided 45% (16 of 36) of all defibrillations and 43% (293 of 666) of all CPR. Conclusions and Relevance: In this study, smartphone dispatch of volunteer responders to OHCAs to retrieve nearby AEDs vs instructions to directly perform CPR did not significantly increase volunteer AED use. High baseline AED attachement rate and crossover may explain why the difference was not significant. Trial Registration: ClinicalTrials.gov Identifier: NCT02992873.

Strategies of Advanced Airway Management in Out-of-Hospital Cardiac Arrest during Intra-Arrest Hypothermia: Insights from the PRINCESS Trial.

BACKGROUND: Trans-nasal evaporative cooling is an effective method to induce intra-arrest therapeutic hypothermia in out-of-hospital cardiac arrest (OHCA). The use of supraglottic airway devices (SGA) instead of endotracheal intubation may enable shorter time intervals to induce cooling. We aimed to study the outcomes in OHCA patients receiving endotracheal intubation (ETI) or a SGA during intra-arrest trans-nasal evaporative cooling. METHODS: This is a pre-specified sub-study of the PRINCESS trial (NCT01400373) that included witnessed OHCA patients randomized during resuscitation to trans-nasal intra-arrest cooling vs. standard care followed by temperature control at 33 °C for 24 h. For this study, patients randomized to intra-arrest cooling were stratified according to the use of ETI vs. SGA prior to the induction of cooling. SGA was placed by paramedics in the first-tier ambulance or by physicians or anesthetic nurses in the second tier while ETI was performed only after the arrival of the second tier. Propensity score matching was used to adjust for differences at the baseline between the two groups. The primary outcome was survival with good neurological outcome, defined as cerebral performance category (CPC) 1-2 at 90 days. Secondary outcomes included time to place airway, overall survival at 90 days, survival with complete neurologic recovery (CPC 1) at 90 days and sustained return of spontaneous circulation (ROSC). RESULTS: Of the 343 patients randomized to the intervention arm (median age 64 years, 24% were women), 328 received intra-arrest cooling and had data on the airway method (n = 259 with ETI vs. n = 69 with SGA). Median time from the arrival of the first-tier ambulance to successful airway management was 8 min for ETI performed by second tier and 4 min for SGA performed by the first or second tier (p = 0.001). No significant differences in the probability of good neurological outcome (OR 1.43, 95% CI 0.64-3.01), overall survival (OR 1.26, 95% CI 0.57-2.55), full neurological recovery (OR 1.17, 95% CI 0.52-2.73) or sustained ROSC (OR 0.88, 95% CI 0.50-1.52) were observed between ETI and SGA. CONCLUSIONS: Among the OHCA patients treated with trans-nasal evaporative intra-arrest cooling, the use of SGA was associated with a significantly shorter time to airway management and with similar outcomes compared to ETI.

Intra-Arrest Therapeutic Hypothermia and Neurologic Outcome in Patients Admitted after Out-of-Hospital Cardiac Arrest: A Post Hoc Analysis of the Princess Trial.

Background: Despite promising results, the role of intra-arrest hypothermia in out-of-hospital cardiac arrest (OHCA) remains controversial. The aim of this study was to assess the effects of trans-nasal evaporative cooling (TNEC) during resuscitation on neurological recovery in OHCA patients admitted alive to the hospital. Methods: A post hoc analysis of the PRINCESS trial, including only patients admitted alive to the hospital, either assigned to TNEC or standard of care during resuscitation. The primary endpoint was favorable neurological outcome (FO) defined as a Cerebral Performance Category (CPC) of 1-2 at 90 days. The secondary outcomes were overall survival at 90 days and CPC 1 at 90 days. Subgroup analyses were performed according to the initial cardiac rhythm. Results: A total of 149 patients in the TNEC and 142 in the control group were included. The number of patients with CPC 1-2 at 90 days was 56/149 (37.6%) in the intervention group and 45/142 (31.7%) in the control group (p = 0.29). Survival and CPC 1 at 90 days was observed in 60/149 patients (40.3%) vs. 52/142 (36.6%; p = 0.09) and 50/149 (33.6%) vs. 35/142 (24.6%; p = 0.11) in the two groups. In the subgroup of patients with an initial shockable rhythm, the number of patients with CPC 1 at 90 days was 45/83 (54.2%) in the intervention group and 27/78 (34.6%) in the control group (p = 0.01). Conclusions: In this post hoc analysis of admitted OHCA patients, no statistically significant benefits of TNEC on neurological outcome at 90 days was found. In patients with initial shockable rhythm, TNEC was associated with increased full neurological recovery.

The ESSENCE-Questionnaire for Neurodevelopmental Problems - A Swedish School-Based Validation Study in 11-Year-Old Children.

Purpose: To determine the prevalence of parent-rated developmental concern using the ESSENCE-Q (Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations-Questionnaire, 12-items, score range 0-24) and to ascertain the predictive validity and optimal cutoff level of the instrument in a school-based sample of 11-year-old children. Methods: In a cross-sectional, school-based study, participants underwent a clinical assessment by a physician and a psychologist, teachers and parents completed the SDQ (Strength and Difficulties Questionnaire), medical health records and national tests were reviewed, and parents independently completed the ESSENCE-Q. In a case-conference outcomes were defined as a) the need for further clinical work-up due to suspected neurodevelopmental problems (NDPs) and b) degree of investigator-rated symptoms/impairment from NDPs on the CGI-S (Clinical Global Impression-Severity instrument, range 1-7, 4-7 defined as clinically symptomatic). Classification and optimal cutoffs of the ESSENCE-Q were determined using ROC (Receiver Operating Characteristic) analysis. Results: Out of 343 eligible children, 223 enrolled, of whom 173 (50% of all eligible) had a parent-rated ESSENCE-Q. At least one of the 12 possible concerns was reported by parents of 36% of participants. Overall, in 101 (57%) participants a work-up was warranted, and 64 (37%) were clinically symptomatic from NDPs. The AUC of the ESSENCE-Q in detecting need for work-up was 0.70 (95% confidence interval [CI] 0.63-0.77), and the AUC in detecting clinically symptomatic participants was 0.82 (95% CI 0.76-0.88). ESSENCE-Q ratings correlated positively with CGI-S scores (r=0.48, p<0.05). A cutoff of ≥3 had the highest accuracy (78%) with a negative predictive value of 82%. Ratings >6 conferred few false positives cases with positive likelihood ratios >10 and positive predictive values of 86% or more. Significance: This study of the ESSENCE-Q in 11-year-old children suggests it might be an acceptable instrument for screening of NDPs in children in middle school, optimally in conjunction with other methods.

Swedish dispatchers' compliance with the American Heart Association performance goals for dispatch-assisted cardiopulmonary resuscitation and its association with survival in out-of-hospital cardiac arrest: A retrospective study.

Aim: We aimed 1) to investigate how Swedish dispatchers perform during emergency calls in accordance with the American Heart Association (AHA) goals for dispatcher-assisted cardiopulmonary resuscitation (DA-CPR), 2) calculate the potential impact on 30-day survival. Methods: This observational study includes a random sample of 1000 out-of-hospital cardiac arrest (OHCA) emergency ambulance calls during 2018 in Sweden. Voice logs were audited to evaluate dispatchers' handling of emergency calls according to the AHA performance goals. Number of possible additional survivors was estimated assuming the timeframes of the AHA performance goals was achieved. Results: A total of 936 cases were included. An OHCA was recognized by a dispatcher in 79% (AHA goal 75%). In recognizable OHCA, dispatchers recognized 85% (AHA goal 95%). Dispatch-directed compressions were given in 61% (AHA goal 75%). Median time to OHCA recognition was 113 s [interquartile range (IQR), 62, 204 s] (AHA goal < 60 s). The first dispatch-directed compression was performed at a median time of 240 s [IQR, 176, 332 s] (AHA goal < 90 s). If eligible patients receive dispatch-directed compressions within the AHA 90 s goal, 73 additional lives may be saved; if all cases are recognized within the AHA 60 s goal, 25 additional lives may be saved. Conclusions: The AHA policy statement serves as a benchmark for all emergency medical dispatch centres (EMDC). Additional effort is needed at Swedish EMDC to achieve AHA goals for DA-CPR. Our study suggests that if EMDC further optimize handling of OHCA calls in accordance with AHA goals, many more lives may be saved.

Wellbeing, emotional response and stress among lay responders dispatched to suspected out-of-hospital cardiac arrests.

BACKGROUND: Systems for smartphone dispatch of lay responders to perform cardio-pulmonary resuscitation (CPR) and bring automated external defibrillators to out-of-hospital cardiac arrests (OHCAs) are advocated by recent international guidelines and emerging worldwide. OBJECTIVES: This study aimed to investigate the emotional responses, posttraumatic stress reactions and levels of wellbeing among smartphone-alerted lay responders dispatched to suspected OHCAs. METHODS: Lay responders were stratified by level of exposure: unexposed (Exp-0), tried to reach (Exp-1), and reached the suspected OHCA (Exp-2). Participants rated their emotional responses online, at 90 minutes and at 4-6 weeks after an incident. Level of emotional response was measured in two dimensions of core affect: "alertness" - from deactivation to activation, and "pleasantness" - from unpleasant to pleasant. At 4-6 weeks, WHO wellbeing index and level of posttraumatic stress (PTSD) were also rated. RESULTS: Altogether, 915 (28%) unexposed and 1471 (64%) exposed responders completed the survey. Alertness was elevated in the exposed groups: Exp-0: 6.7 vs. Exp-1: 7.3 and Exp-2: 7.5, (p < 0.001) and pleasantness was highest in the unexposed group: 6.5, vs. Exp-1: 6.3, and Exp-2: 6.1, (p < 0.001). Mean scores for PTSD at follow-up was below clinical cut-off, Exp-0: 9.9, Exp-1: 8.9 and Exp-2: 8.8 (p = 0.065). Wellbeing index showed no differences, Exp-0: 78.0, Exp-1: 78.5 and Exp-2: 79.9 (p = 0.596). CONCLUSION: Smartphone dispatched lay responders rated the experience as high-energy and mainly positive. No harm to the lay responders was seen. The exposed groups had low posttraumatic stress scores and high-level general wellbeing at follow-up.

Automated external defibrillators delivered by drones to patients with suspected out-of-hospital cardiac arrest.

AIMS: Early defibrillation is critical for the chance of survival in out-of-hospital cardiac arrest (OHCA). Drones, used to deliver automated external defibrillators (AEDs), may shorten time to defibrillation, but this has never been evaluated in real-life emergencies. The aim of this study was to investigate the feasibility of AED delivery by drones in real-life cases of OHCA. METHODS AND RESULTS: In this prospective clinical trial, three AED-equipped drones were placed within controlled airspace in Sweden, covering approximately 80 000 inhabitants (125 km2). Drones were integrated in the emergency medical services for automated deployment in beyond-visual-line-of-sight flights: (i) test flights from 1 June to 30 September 2020 and (ii) consecutive real-life suspected OHCAs. Primary outcome was the proportion of successful AED deliveries when drones were dispatched in cases of suspected OHCA. Among secondary outcomes was the proportion of cases where AED drones arrived prior to ambulance and time benefit vs. ambulance. Totally, 14 cases were eligible for dispatch during the study period in which AED drones took off in 12 alerts to suspected OHCA, with a median distance to location of 3.1 km [interquartile range (IQR) 2.8-3.4). AED delivery was feasible within 9 m (IQR 7.5-10.5) from the location and successful in 11 alerts (92%). AED drones arrived prior to ambulances in 64%, with a median time benefit of 01:52 min (IQR 01:35-04:54) when drone arrived first. In an additional 61 test flights, the AED delivery success rate was 90% (55/61). CONCLUSION: In this pilot study, we have shown that AEDs can be carried by drones to real-life cases of OHCA with a successful AED delivery rate of 92%. There was a time benefit as compared to emergency medical services in cases where the drone arrived first. However, further improvements are needed to increase dispatch rate and time benefits. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT04415398.