Survival After Out-of-Hospital Cardiac Arrest in Relation to Age and Early Identification of Patients With Minimal Chance of Long-Term Survival.

BACKGROUND: Survival after out-of-hospital cardiac arrest has increased during the last decade in Denmark. We aimed to study the impact of age on changes in survival and whether it was possible to identify patients with minimal chance of 30-day survival. METHODS AND RESULTS: Using data from the nationwide Danish Cardiac Arrest Registry (2001─2011), we identified 21 480 patients ≥18 years old with a presumed cardiac-caused out-of-hospital cardiac arrest for which resuscitation was attempted. Patients were divided into 3 preselected age-groups: working-age patients 18 to 65 years of age (33.7%), early senior patients 66 to 80 years of age (41.5%), and late senior patients >80 years of age (24.8%). Characteristics in working-age patients, early senior patients, and late senior patients were as follows: witnessed arrest in 53.8%, 51.1%, and 52.1%; bystander cardiopulmonary resuscitation in 44.7%, 30.3%, and 23.4%; and prehospital shock from a defibrillator in 54.7%, 45.0%, and 33.8% (all P<0.05). Between 2001 and 2011, return of spontaneous circulation on hospital arrival increased: working-age patients, from 12.1% to 34.6%; early senior patients, from 6.4% to 21.5%; and late senior patients, from 4.0% to 15.0% (all P<0.001). Furthermore, 30-day survival increased: working-age patients, 5.8% to 22.0% (P<0.001); and early senior patients, 2.7% to 8.4% (P<0.001), whereas late senior patients experienced only a minor increase (1.5% to 2.0%; P=0.01). Overall, 3 of 9499 patients achieved 30-day survival if they met 2 criteria: had not achieved return of spontaneous circulation on hospital arrival and had not received a prehospital shock from a defibrillator. CONCLUSIONS: All age groups experienced a large temporal increase in survival on hospital arrival, but the increase in 30-day survival was most prominent in the young. With the use of only 2 criteria, it was possible to identify patients with a minimal chance of 30-day survival.

Association of national initiatives to improve cardiac arrest management with rates of bystander intervention and patient survival after out-of-hospital cardiac arrest.

IMPORTANCE: Out-of-hospital cardiac arrest is a major health problem associated with poor outcomes. Early recognition and intervention are critical for patient survival. Bystander cardiopulmonary resuscitation (CPR) is one factor among many associated with improved survival. OBJECTIVE: To examine temporal changes in bystander resuscitation attempts and survival during a 10-year period in which several national initiatives were taken to increase rates of bystander resuscitation and improve advanced care. DESIGN, SETTING, AND PARTICIPANTS: Patients with out-of-hospital cardiac arrest for which resuscitation was attempted were identified between 2001 and 2010 in the nationwide Danish Cardiac Arrest Registry. Of 29,111 patients with cardiac arrest, we excluded those with presumed noncardiac cause of arrest (n = 7390) and those with cardiac arrests witnessed by emergency medical services personnel (n = 2253), leaving a study population of 19,468 patients. MAIN OUTCOMES AND MEASURES: Temporal trends in bystander CPR, bystander defibrillation, 30-day survival, and 1-year survival. RESULTS: The median age of patients was 72 years; 67.4% were men. Bystander CPR increased significantly during the study period, from 21.1% (95% CI, 18.8%-23.4%) in 2001 to 44.9% (95% CI, 42.6%-47.1%) in 2010 (P < .001), whereas use of defibrillation by bystanders remained low (1.1% [95% CI, 0.6%-1.9%] in 2001 to 2.2% [95% CI, 1.5%-2.9%] in 2010; P = .003). More patients achieved survival on hospital arrival (7.9% [95% CI, 6.4%-9.5%] in 2001 to 21.8% [95% CI, 19.8%-23.8%] in 2010; P < .001). Also, 30-day survival improved (3.5% [95% CI, 2.5%-4.5%] in 2001 to 10.8% [95% CI, 9.4%-12.2%] in 2010; P < .001), as did 1-year survival (2.9% [95% CI, 2.0%-3.9%] in 2001 to 10.2% [95% CI, 8.9%-11.6%] in 2010; P < .001). Despite a decrease in the incidence of out-of-hospital cardiac arrests during the study period (40.4 to 34.4 per 100,000 persons in 2001 and 2010, respectively; P = .002), the number of survivors per 100,000 persons increased significantly (P < .001). For the entire study period, bystander CPR was positively associated with 30-day survival, regardless of witnessed status (30-day survival for nonwitnessed cardiac arrest, 4.3% [95% CI, 3.4%-5.2%] with bystander CPR and 1.0% [95% CI, 0.8%-1.3%] without; odds ratio, 4.38 [95% CI, 3.17-6.06]). For witnessed arrest the corresponding values were 19.4% (95% CI, 18.1%-20.7%) vs 6.1% (95% CI, 5.4%-6.7%); odds ratio, 3.74 (95% CI, 3.26-4.28). CONCLUSIONS AND RELEVANCE: In Denmark between 2001 and 2010, an increase in survival following out-of-hospital cardiac arrest was significantly associated with a concomitant increase in bystander CPR. Because of the co-occurrence of other related initiatives, a causal relationship remains uncertain.

Differences between out-of-hospital cardiac arrest in residential and public locations and implications for public-access defibrillation.

BACKGROUND: The majority of out-of-hospital cardiac arrests (OHCAs) occur in residential locations, but knowledge about strategic placement of automated external defibrillators in residential areas is lacking. We examined whether residential OHCA areas suitable for placement of automated external defibrillators could be identified on the basis of demographic characteristics and characterized individuals with OHCA in residential locations. METHODS AND RESULTS: We studied 4828 OHCAs in Copenhagen between 1994 and 2005. The incidence and characteristics of OHCA were examined in every 100 x 100-m (109.4 x 109.4-yd) residential area according to its underlying demographic characteristics. By combining > or =2 demographic characteristics, it was possible to identify 100 x 100-m (109.4 x 109.4-yd) areas with at least 1 arrest every 5.6 years (characterized by >300 persons per area and lowest income) to 1 arrest every 4.3 years (characterized by >300 persons per area, lowest income, low education, and highest age). These areas covered 9.0% and 0.8% of all residential OHCAs, respectively. Individuals with OHCA in residential locations differed from public ones in that the patients were older (70.6 versus 60.6 years; P<0.0001), the ambulance response interval was longer (6.0 versus 5.0 minutes; P<0.0001), arrests occurred more often at night (21.2% versus 11.2%; P<0.0001), the patients had ventricular fibrillation less often (12.8% versus 38.1%; P<0.0001), and the patients had a worse 30-day survival rate (3.2% versus 13.9%; P<0.0001). CONCLUSIONS: On the basis of simple demographic characteristics of a city center, we could identify residential areas suitable for automated external defibrillator placement. Individuals with OHCA in residential locations were more likely to have characteristics associated with poor outcome compared with public arrests.

A synthesis of bacterial and archaeal phenotypic trait data.

A synthesis of phenotypic and quantitative genomic traits is provided for bacteria and archaea, in the form of a scripted, reproducible workflow that standardizes and merges 26 sources. The resulting unified dataset covers 14 phenotypic traits, 5 quantitative genomic traits, and 4 environmental characteristics for approximately 170,000 strain-level and 15,000 species-aggregated records. It spans all habitats including soils, marine and fresh waters and sediments, host-associated and thermal. Trait data can find use in clarifying major dimensions of ecological strategy variation across species. They can also be used in conjunction with species and abundance sampling to characterize trait mixtures in communities and responses of traits along environmental gradients.

Angiotensin-converting enzyme and angiotensin II receptor subtype 2 genotypes in type 1 diabetes and severe hypoglycaemia requiring emergency treatment: a case cohort study.

AIMS: In type 1 diabetes, individual susceptibility to severe hypoglycaemia is likely to be influenced by genetic factors. We have previously reported an association of the deletion (D-) allele of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and the A-allele of the angiotensin II receptor subtype 2 (AT2R) 1675 G>A polymorphism with risk of severe hypoglycaemia in such patients. The aim of this study was to test the hypothesis that these alleles are more frequent in patients suffering from the most severe episodes of hypoglycaemia requiring medical emergency treatment. METHODS: The case cohort study consisted of 108 cases of type 1 diabetic patients with severe hypoglycaemia requiring medical emergency treatment during a 1-year period and 262 consecutive controls without such events. ACE I/D and AT2R 1675G>A genotype distributions were compared between cases and controls. RESULTS: The proportion of D-allele carriers was higher amongst cases than controls (83 vs. 73%; P=0.032). In contrast, AT2R genotype distribution was similar in cases and controls. In a multiple regression analysis, D-allele carriage remained a significant risk factor for being a case [odds ratio: 1.9 (1.0-3.6)] together with male sex, impaired symptomatic awareness of hypoglycaemia and presence of nephropathy. CONCLUSION: The D-allele of the ACE gene is associated with severe hypoglycaemia requiring emergency treatment in type 1 diabetic patients with preserved spontaneous ACE activity. This supports the association between high ACE activity and occurrence of severe hypoglycaemia.

Long-term prognosis after out-of-hospital cardiac arrest.

OBJECTIVE: In this study we aimed to report survival beyond 6 months, including quality of life, for patients after out-of-hospital cardiac arrest (OHCA) with a physician-based EMS in an urban area. METHODS: We collected data related to OHCA prospectively during a 2-year period. Long-term survival was determined by cross-referencing our database with two Danish national registries. Patients older than 18 years who had survived for more than 6 months after OHCA were contacted, and after informed written consent was obtained, an interview was conducted in their home and a questionnaire on quality of life (SF-36) and the mini mental state examination (MMSE) were administered. RESULTS: We had data on 984 cases of OHCA. In 512 cases CPR was attempted and at 6 months, a total of 63 patients were alive corresponding to 12.3% [95% CI: 9.7-15.5%] of all who were treated. Of the 33 patients examined, the median MMSE was 29 (16-30) and two patients, corresponding to 6%, [95% CI: 0.7-20.6%] had an MMSE below 24. Two out of eight aspects of the SF-36 were significantly worse than national norms at the same age, but none of the summary scores differed significantly. CONCLUSION: Survival beyond 6 months was found in 12.3% OHCA in a physician-based EMS. Summary scores of quality of life were not significantly different from the national norm but 2 out of 8 subscores were lower. Signs of dementia were uncommon as only 6% had an MMSE score below 24.

Long-term survival after out-of-hospital cardiac arrest.

OBJECTIVE: The purpose of this study was to assess the long-term survival after OHCA. METHODS: All OHCA-calls where the Copenhagen Mobile Emergency Care Unit (MECU) was involved from 1994 to1998 are included in this study. Data were collected prospectively. Data on long-term survival was obtained from the Danish Causes of Death Registry and the Danish Civil Registration System. We conducted a search to find out whether patients were still alive on 31 January 2005. RESULTS: Resuscitation was indicated and attempted in 1095 cases and 95 patients (8.7%) survived to discharge. Of these 75% had an initial rhythm of VF, 13% had asystole, 10% had PEA and 2% were unknown. Survival was 87% after one year and survival after 10 years was 46% with a significantly lower survival for patients over 60 years. CONCLUSION: Long-term survival after out-of-hospital cardiac arrest in a physician-staffed emergency system was comparable to survival after myocardial infarction with 46% being alive after ten years.

Long-term prognosis for patients with COPD treated in the prehospital setting: Is it influenced by hospital admission?

STUDY OBJECTIVES: Our aim was to assess long-term prognosis for patients with an exacerbation of COPD who were treated by the anesthesiologists of the Mobile Emergency Care Unit (MECU) of Copenhagen. We specifically sought to examine whether mortality was different among patients released before hospital admission and those admitted to the hospital. DESIGN: An observational cohort study with 5-year follow-up. SETTING: Prehospital and university hospital. PATIENTS: Patients with exacerbation of COPD treated by the MECU. MEASUREMENTS: We included all patients treated from 2000 to 2001. In September 2005, we conducted a search to find out whether these patients were still alive, and we analyzed survival using Kaplan-Meier statistics and log-rank test. Patients admitted to the hospital (primarily or secondarily) were compared to patients treated and released before hospital admission. RESULTS: In total, 573 patients with COPD had 995 episodes of exacerbation treated by the MECU in the 2-year period. On September 1, 2005, only 155 patients (27%) were alive. In 245 of the exacerbation episodes (25%) among 163 patients, hospital admission was not necessary primarily, but in 42 of these exacerbations (17%), secondary admission occurred within 48 h. Mortality was significantly higher (p = 0.02) in patients admitted to the hospital either primarily or secondarily, compared to patients treated and released before admission to the hospital. CONCLUSIONS: Mortality was high among COPD patients. Less than one fifth of patients treated at home and released are admitted to hospital secondarily. Mortality was significantly higher among admitted patients. A set of criteria selecting the patient prone to secondary admission is desirable.

Out-of-hospital cardiac arrests in children and adolescents: incidences, outcomes, and household socioeconomic status.

BACKGROUND: There is insufficient knowledge of out-of-hospital cardiac arrest (OHCA) in the very young. OBJECTIVES: This nationwide study sought to examine age-stratified OHCA characteristics and the role of parental socioeconomic differences and its contribution to mortality in the young population. METHODS: All OHCA patients in Denmark, ≤21 years of age, were identified from 2001 to 2010. The population was divided into infants (<1 year); pre-school children (1-5 years); school children (6-15 years); and high school adolescents/young adults (16-21 years). Multivariate logistic regression analyses were used to investigate associations between pre-hospital factors and study endpoints: return of spontaneous circulation and survival. RESULTS: A total of 459 individuals were included. Overall incidence of OHCA was 3.3 per 100,000 inhabitants per year. The incidence rates for infants, pre-school children, school children and high school adolescents were 11.5, 3.5, 1.3 and 5.3 per 100,000 inhabitants. Overall bystander CPR rate was 48.8%, and for age groups: 55.4%, 41.2%, 44.9% and 63.0%, respectively. Overall 30-day survival rate was 8.1%, and for age groups: 1.4%, 4.5%, 16.1% and 9.3%, respectively. High parental education was associated with improved survival after OHCA (OR 3.48, CI 1.27-9.41). Significant crude difference in survival (OR 3.18, CI 1.22-8.34) between high household incomes vs. low household incomes was found. CONCLUSION: OHCA incidences and survival rates varied significantly between age groups. High parental education was found to be associated with improved survival after OHCA.

Outcome of out-of-hospital cardiac arrest--why do physicians withhold resuscitation attempts?

OBJECTIVE: To describe the outcome of out-of-hospital cardiac arrest (OHCA) with a focus on why physicians withhold resuscitation attempts. METHODS: Prospective collection of data during 12 months by the anaesthesiologists from the Advanced Life Support unit (ALS) of the Emergency Medical Service (EMS) according to the Utstein template. RESULTS: In total, 499 OHCA were analysed and 266 patients received cardiopulmonary resuscitation (CPR) by the ALS unit. Initial rhythm was ventricular fibrillation (VF)/pulseless ventricular tachycardia (VT) in 35%, asystole in 38%, and other rhythm in 27%. Of the 266 treated patients, 83 (31%) patients had a spontaneous circulation on admission to hospital. Survival to discharge from hospital was 6.2% for all cases of OHCA, 11.7% for all 266 treated patients, and 20.5% for patients with witnessed cardiac arrest and presumed cardiac aetiology in VF. On arrival, the physician decided in 233 cases to withhold or discontinue CPR. The explanation for this was prolonged anoxia (74%), terminal cancer (8%), and severe trauma (7%). The most common incident locations were the patient's home and nursing homes. These locations were more common in the group where resuscitation was not attempted and these patients were older and the proportions of females and asystole were significantly higher. Bystander CPR was provided in 82 (16%) overall, but only in 8 (3%) in the group where resuscitation was not attempted. CONCLUSION: Survival to discharge from hospital in all cases of OHCA was 6.2% but 20.5% in witnessed, presumed cardiac aetiology in VF. The decision to withhold resuscitation was based upon presumed prolonged anoxia in the majority of cases.

Diurnal variations in incidence and outcome of out-of-hospital cardiac arrest including prior comorbidity and pharmacotherapy: a nationwide study in Denmark.

AIM: To investigate diurnal variations in incidence and outcomes following out-of-hospital cardiac arrest (OHCA). METHODS: OHCA of presumed cardiac etiology were identified through the nationwide Danish Cardiac Arrest Registry (2001-2010). Time of day was divided into three time periods: daytime 07.00-14.59; evening 15.00-22.59; and nighttime 23.00-06.59. RESULTS: We identified 18,929 OHCA patients, aged ≥18 years. The median age was 72 years (IQR 62-80) and the majority were male (67.5%). OHCA occurrence varied across time periods, with 43.9%, 35.7% and 20.6% occurring during daytime, evening and nighttime, respectively. Nighttime patients were more likely to have: severe comorbidity (i.e. COPD), arrest in private home (87.2% vs. 69.0% and 73.0% daytime and evening, respectively), non-witnessed arrest (51.2% vs. 48.4% and 43.7%), no bystander CPR (75.9% vs. 68.4% and 66.1%), longer time interval from recognition of OHCA to rhythm analysis (12 min vs. 11 min and 11 min), and non-shockable heart rhythm (80.1% vs. 70.3% and 69.4%), all p<0.0001. Nighttime patients were less likely to achieve return of spontaneous circulation on arrival at the hospital (7.5% vs. 14.8% and 15.1%) and 1-year survival (2.8% vs. 7.2% and 7.1%), p<0.0001. Overall, the lower 1-year survival rate persisted after adjusting for patient-related and cardiac-arrest related characteristics mentioned above (OR 0.47, 95%CI 0.37-0.59; OR 0.51, 95%CI 0.40-0.65, compared to daytime and evening, respectively). CONCLUSIONS: We found nighttime patients to have a lower survival compared to daytime and evening that persisted when adjusting for patient-related and cardiac-arrest related characteristics including comorbidities.

Survival after out-of-hospital cardiac arrest in relation to sex: a nationwide registry-based study.

AIM: Crude survival has increased following an out-of-hospital cardiac arrest (OHCA). We aimed to study sex-related differences in patient characteristics and survival during a 10-year study period. METHODS: Patients≥12 years old with OHCA of a presumed cardiac cause, and in whom resuscitation was attempted, were identified through the Danish Cardiac Arrest Registry 2001-2010. A total of 19,372 patients were included. RESULTS: One-third were female, with a median age of 75 years (IQR 65-83). Compared to females, males were five years younger; and less likely to have severe comorbidities, e.g., chronic obstructive pulmonary disease (12.8% vs. 16.5%); but more likely to have arrest outside of the home (29.4% vs. 18.7%), receive bystander CPR (32.9% vs. 25.9%), and have a shockable rhythm (32.6% vs. 17.2%), all p<0.001. Thirty-day crude survival increased in males (3.0% in 2001 to 12.9% in 2010); and in females (4.8% in 2001 to 6.7% in 2010), p<0.001. Multivariable logistic regression analyses adjusted for patient characteristics including comorbidities, showed no survival difference between sexes in patients with a non-shockable rhythm (OR 1.00; CI 0.72-1.40), while female sex was positively associated with survival in patients with a shockable rhythm (OR 1.31; CI 1.07-1.59). Analyses were rhythm-stratified due to interaction between sex and heart rhythm; there was no interaction between sex and calendar-year. CONCLUSIONS: Temporal increase in crude survival was more marked in males due to poorer prognostic characteristics in females with a lower proportion of shockable rhythm. In an adjusted model, female sex was positively associated with survival in patients with a shockable rhythm.

Hospital admissions and pharmacotherapy before out-of-hospital cardiac arrest according to age.

BACKGROUND: The underlying etiology of sudden cardiac death varies with age and is likely to be reflected in type and number of healthcare contacts. We aimed to determine the specific type of healthcare contact shortly before out-of-hospital cardiac arrest (OHCA) across ages. METHODS: OHCA patients were identified in the nationwide Danish Cardiac Arrest Register and Copenhagen Medical Emergency Care Unit (2001-2006). We matched every OHCA patients with 10 controls on sex and age. Healthcare contacts were evaluated 30 days before event by individual-level-linkage of nationwide registers. RESULTS: We identified 16,924 OHCA patients, median age 70.0 years (Q1-Q3: 59-80). OHCA patients had a higher number of hospitalizations and received more pharmacotherapy compared to the control population across all ages (p for difference <0.001). OHCA patients aged 70-79 and 80-89 years had the highest proportion of hospitalizations (70%) and pharmacotherapy (73%), respectively. In general, the association between OHCA and hospitalizations and pharmacotherapy was more pronounced among the youngest OHCA patients compared to controls. OHCA patients in age groups 14-19, 20-29, 30-39 were ~5 times more likely to be in contact with the healthcare service than the control population (p for difference <0.001). Similarly, OHCA patients in the oldest age groups (60-69, 70-79, 80-89, >89) were <2 times more likely to be in contact with the healthcare services shortly before OHCA compared to the control population (p for difference <0.001). CONCLUSION: Young OHCA patients are more likely to be in contact with the healthcare services compared with an age and sex matched control population suggestive of traits that make them stand out from the general population.