Bystander cardiopulmonary resuscitation and long-term outcomes in out-of-hospital cardiac arrest according to location of arrest.

Aims: Bystander cardiopulmonary resuscitation (CPR) has increased in several countries following nationwide initiatives to facilitate bystander resuscitative efforts in out-of-hospital cardiac arrest (OHCA). We examined the importance of public or residential location of arrest on temporal changes in bystander CPR and outcomes. Methods and results: From the nationwide Danish Cardiac Arrest Registry, all OHCAs from 2001 to 2014 of presumed cardiac cause and between 18 and 100 years of age were identified. Arrests witnessed by emergency medical services personnel were excluded. Of 25 505 OHCAs, 26.4% (n = 6738) and 73.6% (n = 18 767) were in public and residential locations, respectively. Bystander CPR increased during 2001-2014 in both locations: from 36.4% [95% confidence interval (CI) 30.6-42.6%] to 83.1% (95% CI 80.0-85.8%) in public (P < 0.001) and from 16.0% (95% CI 13.2-19.3%) to 61.0% (95% CI 58.7-63.2%) in residential locations (P < 0.001). Concurrently, 30-day survival increased in public from 6.4% (95% CI 4.0-10.0%) to 25.2% (95% CI 22.1-28.7%) (P < 0.001), and in residential from 2.9% (95% CI 1.8-4.5%) to 10.0% (95% CI 8.7-11.4%) (P < 0.001). Among 2281 30-day survivors, 1-year risk of anoxic brain damage/nursing home admission during 2001-2014 decreased from 18.8% (95% CI 6.6-43.0%) to 6.8% (95% CI 3.9-11.8%) in public (P < 0.001), whereas the corresponding change was insignificant in residential locations from 11.8% (95% CI 3.3-34.3) to 17.6% (95% CI 12.7-23.9%) (P = 0.52). Conclusion: During 2001-2014, bystander CPR and 30-day survival more than doubled in both public and residential OHCA locations. A significant decrease in anoxic brain damage/nursing home admission was observed among 30-day survivors in public, but not among survivors from residential OHCAs.

Improving bystander defibrillation in out-of-hospital cardiac arrests at home.

AIMS: Most out-of-hospital cardiac arrests occur at home with dismal bystander defibrillation rates. We investigated automated external defibrillator coverage of home arrests, and the proportion potentially reachable with an automated external defibrillator before emergency medical service arrival according to different bystander activation strategies. METHODS AND RESULTS: Cardiac arrests in homes (private/nursing/senior homes) in Copenhagen, Denmark (2008-2016) and registered automated external defibrillators (2007-2016), were identified. Automated external defibrillator coverage (distance from arrest to automated external defibrillator) and accessibility at the time of arrest were examined according to route distance to nearest automated external defibrillator and emergency medical service response time. The proportion of arrests reachable with an automated external defibrillator by bystander was calculated using two-way (from patient to automated external defibrillator and back) and one-way (from automated external defibrillator to patient) potential activation strategies. Of 1879 home arrests, automated external defibrillator coverage ≤100 m was low (6.3%) and a two-way bystander could potentially only retrieve an accessible automated external defibrillator before emergency medical service in 31.1% (n=37) of cases. If a bystander only needed to travel one-way to bring an automated external defibrillator (≤100 m, ≤250 m and ≤500 m), 45.4% (n=54/119), 37.1% (n=196/529) and 29.8% (n=350/1174) could potentially be reached before the emergency medical service based on current automated external defibrillator accessibility. CONCLUSIONS: Few home arrests were reachable with an automated external defibrillator before emergency medical service if bystanders needed to travel from patient to automated external defibrillator and back. However, nearly one-third of arrests ≤500 m of an automated external defibrillator could be reached before emergency medical service arrival if the bystander only needed to travel one-way from the automated external defibrillator to the patient.

Out-of-hospital cardiac arrest: 30-day survival and 1-year risk of anoxic brain damage or nursing home admission according to consciousness status at hospital arrival.

AIM: To investigate the association between consciousness status at hospital arrival and long-term outcomes in out-of-hospital cardiac arrest (OHCA) patients. METHODS: OHCAs between 18-100 years of age were identified from the Danish Cardiac Arrest Registry during 2005-2014. Patients with return of spontaneous circulation (ROSC) or ongoing cardiopulmonary resuscitation (CPR) at hospital arrival were included. Thirty-day survival was evaluated using Kaplan-Meier estimates. Risk of anoxic brain damage or nursing home admission and return to work among 30-day survivors were evaluated using Aalen-Johansen estimates and cause-specific Cox regression. RESULTS: Upon hospital arrival of 13,953 OHCA patients, 776 (5.6%) had ROSC and were conscious (Glasgow Coma Score [GCS]>8), 5205 (37.3%) had ROSC, but were comatose (GCS ≤ 8), and 7972 (57.1%) had ongoing CPR. Thirty-day survival according to status at hospital arrival among patients that were conscious, comatose, or had ongoing CPR was 89.0% (95% confidence interval [CI] 86.8%-91.2%), 39.0% (95% CI 37.6%-40.3%), and 1.2% (95% CI 1.0%-1.4%), respectively. Among 30-day survivors, 1-year risks of new onset anoxic brain damage or nursing home admission according to consciousness status were 2.4% (95% CI 1.2%-3.6%), 12.9% (95% CI 11.4%-14.3%), and 19.4% (95% CI 11.3%-27.4%), respectively. Among 30-day working-age survivors, more than 65% in each group returned to work within 5 years. CONCLUSION: Consciousness status at hospital arrival was strongly associated with 30-day survival in OHCA patients. Among 30-day survivors, a minority was diagnosed with anoxic brain damage or admitted to a nursing home and the majority returned to work independent of consciousness status at hospital arrival.

Survival of patients with and without diabetes following out-of-hospital cardiac arrest: A nationwide Danish study.

BACKGROUND: Research regarding out-of-hospital cardiac arrest (OHCA) survival of diabetes patients is sparse and it remains unknown whether initiatives to increase OHCA survival benefit diabetes and non-diabetes patients equally. We therefore examined overall and temporal survival in diabetes and non-diabetes patients following OHCA. METHODS: Adult presumed cardiac-caused OHCAs were identified from the Danish Cardiac Arrest Registry (2001-2014). Associations between diabetes and return of spontaneous circulation upon hospital arrival and 30-day survival were estimated with logistic regression adjusted for patient- and OHCA-related characteristics. RESULTS: In total, 28,955 OHCAs were included of which 4276 (14.8%) had diabetes. Compared with non-diabetes patients, diabetes patients had more comorbidities, same prevalence of bystander-witnessed arrests (51.7% vs. 52.7%) and bystander cardiopulmonary resuscitation (43.2% vs. 42.0%), more arrests in residential locations (77.3% vs. 73.0%) and were less likely to have shockable heart rhythm (23.5% vs. 27.9%). Temporal increases in return of spontaneous circulation and 30-day survival were seen for both groups (return of spontaneous circulation: 8.8% in 2001 to 22.3% in 2014 (diabetes patients) vs. 7.8% in 2001 to 25.7% in 2014 (non-diabetes patients); and 30-day survival: 2.8% in 2001 to 9.7% in 2014 vs. 3.5% to 14.8% in 2014, respectively). In adjusted models, diabetes was associated with decreased odds of return of spontaneous circulation (odds ratio 0.74 (95% confidence interval 0.66-0.82)) and 30-day survival (odds ratio 0.56 (95% confidence interval 0.48-0.65)) (interaction with calendar year p=0.434 and p=0.243, respectively). CONCLUSION: No significant difference in temporal survival was found between the two groups. However, diabetes was associated with lower odds of return of spontaneous circulation and 30-day survival.

Out-of-hospital cardiac arrest in patients with psychiatric disorders - Characteristics and outcomes.

AIMS: To investigate whether the recent improvements in pre-hospital cardiac arrest-management and survival following out-of-hospital cardiac arrest (OHCA) also apply to OHCA patients with psychiatric disorders. METHODS: We identified all adult Danish patients with OHCA of presumed cardiac cause, 2001-2015. Psychiatric disorders were defined by hospital diagnoses up to 10 years before OHCA and analyzed as one group as well as divided into five subgroups (schizophrenia-spectrum disorders, bipolar disorder, depression, substance-induced mental disorders, other psychiatric disorders). Association between psychiatric disorders and pre-hospital OHCA-characteristics and 30-day survival were assessed by multiple logistic regression. RESULTS: Of 27,523 OHCA-patients, 4772 (17.3%) had a psychiatric diagnosis. Patients with psychiatric disorders had lower odds of 30-day survival (0.37 95% confidence interval 0.32-0.43) compared with other OHCA-patients. Likewise, they had lower odds of witnessed status (0.75 CI 0.70-0.80), bystander cardiopulmonary resuscitation (CPR) (0.77 CI 0.72-0.83), shockable heart rhythm (0.37 95% CI, 0.33-0.40), and return of spontaneous circulation (ROSC) at hospital arrival (0.66 CI 0.59-0.72). Similar results were seen in all five psychiatric subgroups. The difference in 30-day survival between patients with and without psychiatric disorders increased in recent years: from 8.4% (CI 7.0-10.0%) in 2006 to 13.9% (CI 12.4-15.4%) in 2015 and from 7.0% (4.3-10.8%) in 2006 to 7.0% (CI 4.5-9.7%) in 2015, respectively. CONCLUSION: Patients with psychiatric disorders have lower survival following OHCA compared to non-psychiatric patients and the gap between the two groups has widened over time.

Risk of post-discharge fall-related injuries among adult patients with syncope: A nationwide cohort study.

BACKGROUND: Syncope could be related to high risk of falls and injury in adults, but documentation is sparse. We examined the association between syncope and subsequent fall-related injuries in a nationwide cohort. METHODS: By cross-linkage of nationwide registers, all residents ≥18 years with a first-time diagnosis of syncope were identified between 1997-2012. Syncope patients were matched 1:1 with individuals from the general population. The absolute one-year risk of fall-related injuries, defined as fractures and traumatic head injuries requiring hospitalization, was calculated using Aalen-Johansen estimator. Ratios of the absolute one-year risk of fall-related injuries (ARR) were assessed by absolute risk regression analysis. RESULTS: We identified 125,763 patients with syncope: median age 65 years (interquartile range 46-78). At one year, follow-up was complete for 99.8% where a total of 8394 (6.7%) patients sustained a fall-related injury requiring hospitalization, of which 1606 (19.1%) suffered hip fracture. In the reference group, 4049 (3.2%) persons had a fall-related injury. The one-year ARR of a fall-related injury was 1.79 (95% confidence interval 1.72-1.87, P<0.001) in patients with syncope compared with the reference group; however, increased ARR was not exclusively in older patients. Factors independently associated with increased ARR of fall-related injuries in the syncope population were: injury in past 12 months, 2.39 (2.26-2.53, P<0.001), injury in relation to the syncope episode, 1.62 (1.49-1.77, P<0.001), and depression, 1.37 (1.30-1.45, P<0.001). CONCLUSION: Patients with syncope were at 80% increased risk of severe fall-related injuries within the year following discharge. Notably, increased risk was not exclusively in older patients.

Out-of-hospital cardiac arrest: Probability of bystander defibrillation relative to distance to nearest automated external defibrillator.

AIMS: Despite wide dissemination of automated external defibrillators (AEDs), bystander defibrillation rates remain low. We aimed to investigate how route distance to the nearest accessible AED was associated with probability of bystander defibrillation in public and residential locations. METHODS: We used data from the nationwide Danish Cardiac Arrest Registry and the Danish AED Network to identify out-of-hospital cardiac arrests and route distances to nearest accessible registered AED during 2008-2013. The association between route distance and bystander defibrillation was described using restricted cubic spline logistic regression. RESULTS: We included 6971 out-of-hospital cardiac arrest cases. The proportion of arrests according to distance in meters (≤100, 101-200, >200) to the nearest accessible AED was: 4.6% (n=320), 5.3% (n=370), and 90.1% (n=6281), respectively. For cardiac arrests in public locations, the probability of bystander defibrillation at 0, 100 and 200m from the nearest AED was 35.7% (95% confidence interval 28.0%-43.5%), 21.3% (95% confidence interval 17.4%-25.2%), and 13.7% (95% confidence interval 10.1%-16.8%), respectively. The corresponding numbers for cardiac arrests in residential locations were 7.0% (95% confidence interval -2.1%-16.1%), 1.5% (95% confidence interval 0.002%-2.8%), and 0.9% (95% confidence interval 0.0005%-1.7%), respectively. CONCLUSIONS: In public locations, the probability of bystander defibrillation decreased rapidly within the first 100m route distance from cardiac arrest to nearest accessible AED whereas the probability of bystander defibrillation was low for all distances in residential areas.

Non-steroidal anti-inflammatory drug use is associated with increased risk of out-of-hospital cardiac arrest: a nationwide case-time-control study.

Aims: Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used and have been associated with increased cardiovascular risk. Nonetheless, it remains unknown whether use of NSAIDs is associated with out-of-hospital cardiac arrest (OHCA). Methods and results: From the nationwide Danish Cardiac Arrest Registry, all persons with OHCA during 2001-10 were identified. NSAID use 30 days before OHCA was categorized as follows: diclofenac, naproxen, ibuprofen, rofecoxib, celecoxib, and other. Risk of OHCA associated with use of NSAIDs was analysed by conditional logistic regression in case-time-control models matching four controls on sex and age per case to account for variation in drug utilization over time. We identified 28 947 persons with OHCA of whom 3376 were treated with an NSAID up to 30 days before OHCA. Ibuprofen and diclofenac were the most commonly used NSAIDs and represented 51.0% and 21.8% of total NSAID use, respectively. Use of diclofenac (odds ratio [OR], 1.50 [95% confidence interval (CI) 1.23-1.82]) and ibuprofen [OR, 1.31 (95% CI 1.14-1.51)] was associated with a significantly increased risk of OHCA. Use of naproxen [OR, 1.29 (95% CI 0.77-2.16)], celecoxib [OR, 1.13 (95% CI 0.74-1.70)], and rofecoxib (OR, 1.28 [95% CI 0.74-1.70)] was not significantly associated with increased risk of OHCA; however, these groups were characterized by few events. Conclusion: Use of non-selective NSAIDs was associated with an increased early risk of OHCA. The result was driven by an increased risk of OHCA in ibuprofen and diclofenac users.

Lay Bystanders' Perspectives on What Facilitates Cardiopulmonary Resuscitation and Use of Automated External Defibrillators in Real Cardiac Arrests.

BACKGROUND: Many patients who suffer an out-of-hospital cardiac arrest will fail to receive bystander intervention (cardiopulmonary resuscitation [CPR] or defibrillation) despite widespread CPR training and the dissemination of automated external defibrillators (AEDs). We sought to investigate what factors encourage lay bystanders to initiate CPR and AED use in a cohort of bystanders previously trained in CPR techniques who were present at an out-of-hospital cardiac arrest. METHODS AND RESULTS: One-hundred and twenty-eight semistructured qualitative interviews with CPR-trained lay bystanders to consecutive out-of-hospital cardiac arrest, where an AED was present were conducted (from January 2012 to April 2015, in Denmark). Purposive maximum variation sampling was used to establish the breadth of the bystander perspective. Twenty-six of the 128 interviews were chosen for further in-depth analyses, until data saturation. We used cross-sectional indexing (using software), and inductive in-depth thematic analyses, to identify those factors that facilitated CPR and AED use. In addition to prior hands-on CPR training, the following were described as facilitators: prior knowledge that intervention is crucial in improving survival, cannot cause substantial harm, and that the AED will provide guidance through CPR; prior hands-on training in AED use; during CPR performance, teamwork (ie, support), using the AED voice prompt and a ventilation mask, as well as demonstrating leadership and feeling a moral obligation to act. CONCLUSIONS: Several factors other than previous hands-on CPR training facilitate lay bystander instigation of CPR and AED use. The recognition and modification of these factors may increase lay bystander CPR rates and patient survival following an out-of-hospital cardiac arrest.

Prolonged cardiopulmonary resuscitation and outcomes after out-of-hospital cardiac arrest.

AIM: It is unclear whether prolonged resuscitation can result in successful outcome following out-of-hospital cardiac arrests (OHCA). We assessed associations between duration of pre-hospital resuscitation on survival and functional outcome following OHCA in patients achieving pre-hospital return of spontaneous circulation (ROSC). METHODS: We included 1316 adult OHCA individuals with pre-hospital ROSC (2005-2011) handled by the largest nationwide ambulance provider in Denmark. Patients were stratified into 0-5, 6-10, 11-15, 16-20, 21-25 and >25min of cardiopulmonary resuscitation (CPR) by emergency medical services until ROSC was achieved. Nursing home admission and diagnosis of anoxic brain damage were measured as proxies of poor neurological/functional outcomes. FINDINGS: Median time from CPR initiation to ROSC was 12min (IQR: 7-18) while 20.4% achieved ROSC after >25min. Overall, 37.5% (494) of the study population achieved 30-day survival. Thirty-day survival was inversely related to minutes of CPR to ROSC: ranging from 59.6% (127/213) for ≤5min to 13.8% (19/138) for >25min. If bystander initiated CPR before ambulance arrival, corresponding values ranged from 70.4% (107/152) to 21.8% (12/55). Of 30-day survivors, patients discharged to own home rather than nursing home ranged from 95.0% (124/127) to 84.7% (18/19), respectively. Of 30-day survivors, patients discharged without diagnosis of anoxic brain damage ranged from 98.4% (125/127) to 73.7% (14/19) for corresponding intervals. CONCLUSION: Even those requiring prolonged resuscitation duration prior to ROSC had meaningful survival rates with the majority of survivors able to return to live in own homes. These data suggest that prolonged resuscitation is not futile.