Incidence and percentage of survival after cardiac arrest outside and inside hospital: A comparison between two regions in Sweden.

Aim: To compare the incidence and percentage of survival after cardiac arrest outside and inside hospital where cardiopulmonary resuscitation (CPR) had been started between two regions in Sweden in a 10-year perspective. Methods: A retrospective observational study including CPR treated patients both after out-of-hospital and in-hospital cardiac arrest (OHCA and IHCA) in Sweden, 2013-2022. Data was retrieved from the Swedish Registry of Cardiopulmonary Resuscitation (SRCR). Results: The overall incidence of OHCA and IHCA events were 2,940 in Dalarna (having a lower population and population density) and 16,187 in Västra Götaland (having a higher population and population density). The overall incidence of survival when OHCA and IHCA were combined was 20 per 100,000 person years in Dalarna and 19 per 100,000 person years in Västra Götaland. The corresponding result for OHCA was 9 versus 7 and for IHCA 11 versus 12. The overall percentage of survival was 20% in Dalarna and 19% in Västra Götaland. The corresponding result for OHCA was 13% versus 10% and for IHCA 37% versus 36%. Conclusion: Overall, there was no marked difference neither in incidence nor in percentage of survival after cardiac arrest between the two regions. However, regarding cardiac arrest that took place outside hospital both incidence and percentage of survival was higher in Dalarna than in Västra Götaland despite the fact that the former had lower population density.

Traumatic cardiac arrest in Sweden 1990-2016 - a population-based national cohort study.

BACKGROUND: Trauma is a main cause of death among young adults worldwide. Patients experiencing a traumatic cardiac arrest (TCA) certainly have a poor prognosis but population-based studies are sparse. Primarily to describe characteristics and 30-day survival following a TCA as compared with a medical out-of-hospital cardiac arrest (medical CA). METHODS: A cohort study based on data from the nationwide, prospective population-based Swedish Registry for Cardiopulmonary Resuscitation (SRCR), a medical cardiac arrest registry, between 1990 and 2016. The definition of a TCA in the SRCR is a patient who is unresponsive with apnoea where cardiopulmonary resuscitation and/or defibrillation have been initiated and in whom the Emergency Medical Services (EMS, mainly a nurse-based system) reported trauma as the aetiology. Outcome was overall 30-day survival. Descriptive statistics as well as multivariable logistic regression models were used. RESULTS: In all, between 1990 and 2016, 1774 (2.4%) cases had a TCA and 72,547 had a medical CA. Overall 30-day survival gradually increased over the years, and was 3.7% for TCAs compared to 8.2% following a medical CA (p < 0.01). Among TCAs, factors associated with a higher 30-day survival were bystander witnessed and having a shockable initial rhythm (adjusted OR 2.67, 95% C.I. 1.15-6.22 and OR 8.94 95% C.I. 4.27-18.69, respectively). DISCUSSION: Association in registry-based studies do not imply causality but TCA had short time intervals in the chain of survival as well as high rates of bystander-CPR. CONCLUSION: In a medical CA registry like ours, prevalence of TCAs is low and survival is poor. Registries like ours might not capture the true incidence. However, many individuals do survive and resuscitation in TCAs should not be seen futile.

Medical versus non medical etiology in out-of-hospital cardiac arrest-Changes in outcome in relation to the revised Utstein template.

INTRODUCTION: The Utstein-style recommendations for reporting etiology and outcome in out-of-hospital cardiac arrest (OHCA) from 2004 have recently been revised. Among other etiologies a medical category is now introduced, replacing the cardiac category from Utstein template 2004. AIM: The aim of this study is to describe characteristics and temporal trends from reporting OHCA etiology according to the revised Utstein template 2014 in regards to patient characteristics and 30-day survival rates. METHODS: This registry study is based on consecutive OHCA cases reported from the Emergency medical services (EMS) to the Swedish Registry of Cardiopulmonary Resuscitation (SRCR) 1992-2014. Characteristics, including a presumed cardiac etiology in Utstein template 2004, were transcribed to a medical etiology in Utstein template 2014. RESULTS: Of a total of n=70,846 cases, 92% were categorized as having a medical etiology and 8% as having a non-medical cause. Using the new classifications, the 30-day survival rate has significantly increased over a 20-year period from 4.7% to 11.0% in the medical group and from 3% to 9.9% in the non-medical group (p≤0.001). Trauma was the most common cause in OHCA of a non-medical etiology (26%) with a 30-day survival rate of 3.4% whilst drowning and drug overdose had the highest survival rates (14% and 10% respectively). CONCLUSION: Based on Utstein 2014 categories of etiology, overall survival after OHCA with a medical etiology has more than doubled in a 20-year period and tripled for non-medical cases. Patients with a medical etiology found in a shockable rhythm have the highest chance of survival. There is great variability in characteristics among non-medical cases.

Validity of reported data in the Swedish Cardiac Arrest Register in selected parts in Sweden.

AIM: To describe differences and similarities between reported and non-reported data in the Swedish Cardiac Arrest Register in selected parts in Sweden. METHODS: Prospective and retrospective data for treated OHCA patients in Sweden, 2008-2010, were compared in the Swedish Cardiac Arrest Register. Data were investigated in three Swedish counties, which represented one third of the population. The recording models varied. Prospective data are those reported by the emergency medical service (EMS) crews, while retrospective data are those missed by the EMS crews but discovered afterwards by cross-checking with the local ambulance register. RESULT: In 2008-2010, the number of prospectively (n=2398) and retrospectively (n=800) reported OHCA cases was n=3198, which indicates a 25% missing rate. When comparing the two groups, the mean age was higher in patients who were reported retrospectively (69 years vs. 67 years; p=0.003). There was no difference between groups with regard to gender, time of day and year of OHCA, witnessed status or initial rhythm. Bystander cardiopulmonary resuscitation (CPR) was more frequent among patients who were reported prospectively (65% vs. 60%; p=0.023), whereas survival to one month was higher among patients who were reported retrospectively (9.2% vs. 11.9%; p=0.035). CONCLUSION: Among 3198 cases of OHCA in three counties in Sweden, 800 (25%) were not reported prospectively by the EMS crews but were discovered retrospectively as missing cases. Patients who were reported retrospectively differed from prospectively reported cases by being older, having less frequently received bystander CPR but having a higher survival rate. Our data suggest that reports on OHCA from national quality registers which are based on prospectively recorded data may be influenced by selection bias.

Improvements in logistics could increase survival after out-of-hospital cardiac arrest in Sweden.

OBJECTIVES: In a review based on estimations and assumptions, to report the estimated number of survivors after out-of-hospital cardiac arrest (OHCA) in whom cardiopulmonary resuscitation (CPR) was started and to speculate about possible future improvements in Sweden. DESIGN: An observational study. SETTING: All ambulance organisations in Sweden. SUBJECTS: Patients included in the Swedish Cardiac Arrest Registry who suffered an OHCA between January 1, 2008 and December 31, 2010. Approximately 80% of OHCA cases in Sweden in which CPR was started are included. INTERVENTIONS: None RESULTS: In 11 005 patients, the 1-month survival rate was 9.4%. There are approximately 5000 OHCA cases annually in which CPR is started and 30-day survival is achieved in up to 500 patients yearly (6 per 100 000 inhabitants). Based on findings on survival in relation to the time to calling for the Emergency Medical Service (EMS) and the start of CPR and defibrillation, it was estimated that, if the delay from collapse to (i) calling EMS, (ii) the start of CPR, and (iii) the time to defibrillation were reduced to <2 min, <2 min, and <8 min, respectively, 300-400 additional lives could be saved. CONCLUSION: Based on findings relating to the delay to calling for the EMS and the start of CPR and defibrillation, we speculate that 300-400 additional OHCA patients yearly (4 per 100 000 inhabitants) could be saved in Sweden.

Association between population density and reported incidence, characteristics and outcome after out-of-hospital cardiac arrest in Sweden.

AIM: To describe the reported incidence of out of hospital cardiac arrest (OHCA) and the characteristics and outcome after OHCA in relation to population density in Sweden. METHODS: All patients participating in the Swedish Cardiac Arrest Register between 2008 and 2009 in (a) 20 of 21 regions (n=6457) and in (b) 165 of 292 municipalities (n=3522) in Sweden, took part in the survey. RESULTS: The regional population density varied between 3 and 310 inhabitants per km(2) in 2009. In 2008-2009, the number of reported cardiac arrests varied between 13 and 52 per 100,000 inhabitants and year. Survival to 1 month varied between 2% and 14% during the same period in different regions. With regard to population density, based on municipalities, bystander CPR (p=0.04) as well as cardiac etiology (p=0.002) were more frequent in less populated areas. Ambulance response time was longer in less populated areas (p<0.0001). There was no significant association between population density and survival to 1 month after OHCA or incidence (adjusted for age and gender) of OHCA. CONCLUSION: There was no significant association between population density and survival to 1 month after OHCA or incidence (adjusted for age and gender) of OHCA. However, bystander CPR, cardiac etiology and longer response times were more frequent in less populated areas.

Education in cardiopulmonary resuscitation in Sweden and its clinical consequences.

AIM: To describe the use of cardiopulmonary resuscitation (CPR) training programmes in Sweden for 25 years and relate those to changes in the percentage of patients with out of hospital cardiac arrest (OHCA) who receive bystander CPR. METHODS: Information was gathered from (a) the Swedish CPR training registry established in 1983 and includes most Swedish education programmes in CPR and (b) the Swedish Cardiac Arrest Register (SCAR) established in 1990 and currently covers about 70% of ambulance districts in Sweden. RESULTS: CPR education in Sweden functions according to a cascade principle (instructor-trainers who train instructors who then train rescuers in CPR). Since 1989, 5000 instructor-trainers have taught more than 50,000 instructors who have taught nearly 2 million of Sweden's 9 million inhabitants adult CPR. This is equivalent to one new rescuer per 100 inhabitants every year in Sweden. In addition, since 1989, there are 51,000 new rescuers in Advanced Life Support (ALS), since 1996, 41,000 new Basic Life Support (BLS) rescuers with Automated External Defibrillation (AED) training, and since 1998, there are 93,000 new rescuers in child CPR. As a result of this CPR training the number of bystander CPR attempts for OHCA in Sweden increased from 31% in 1992 to 55% in 2007. CONCLUSION: By using a cascade principle for CPR education nearly 2 million rescuers were educated in Sweden (9 million inhabitants) between 1989 and 2007. This resulted in a marked increase in bystander CPR attempts.