Andreas Claesson

Improved outcome in Sweden after out-of-hospital cardiac arrest and possible association with improvements in every link in the chain of survival

AIMSnTo describe out-of-hospital cardiac arrest (OHCA) in Sweden from a long-term perspective in terms of changes in outcome and circumstances at resuscitation.nnnMETHODS AND RESULTSnAll cases of OHCA (n = 59,926) reported to the Swedish Cardiac Arrest Register from 1992 to 2011 were included. The number of cases reported (n/100,000 person-years) increased from 27 (1992) to 52 (2011). Crew-witnessed cases, cardiopulmonary resuscitation prior to the arrival of the emergency medical service (EMS), and EMS response time increased (P < 0.0001). There was a decrease in the delay from collapse to calling for the EMS in all patients and from collapse to defibrillation among patients found in ventricular fibrillation (P < 0.0001). The proportion of patients found in ventricular fibrillation decreased from 35 to 25% (P < 0.0001). Thirty-day survival increased from 4.8 (1992) to 10.7% (2011) (P < 0.0001), particularly among patients found in a shockable rhythm and patients with return of spontaneous circulation (ROSC) at hospital admission. Among patients hospitalized with ROSC in 2008-2011, 41% underwent therapeutic hypothermia and 28% underwent percutaneous coronary intervention. Among 30-day survivors in 2008-2011, 94% had a cerebral performance category score of 1 or 2 at discharge from hospital and the results were even better if patients were found in a shockable rhythm.nnnCONCLUSIONnFrom a long-term perspective, 30-day survival after OHCA in Sweden more than doubled. The increase in survival was most marked among patients found in a shockable rhythm and those hospitalized with ROSC. There were improvements in all four links in the chain of survival, which might explain the improved outcome.

Delay and performance of cardiopulmonary resuscitation in surf lifeguards after simulated cardiac arrest due to drowning.

PURPOSEnTo describe time delay during surf rescue and compare the quality of cardiopulmonary resuscitation (CPR) before and after exertion in surf lifeguards.nnnMETHODSnA total of 40 surf lifeguards at the Tylösand Surf Lifesaving Club in Sweden (65% men; age, 19-43 years) performed single-rescuer CPR for 10 minutes on a Laerdal SkillmeteÔ Resusci Anne manikin. The test was repeated with an initial simulated surf rescue on an unconscious 80-kg victim 100 m from the shore. The time to victim, to first ventilation, and to the start of CPR was documented.nnnRESULTSnThe mean time in seconds to the start of ventilations in the water was 155 ± 31 (mean ± SD) and to the start of CPR, 258 ± 44. Men were significantly faster during rescue (mean difference, 43 seconds) than women (P = .002). The mean compression depth (millimeters) at rest decreased significantly from 0-2 minutes (42.6 ± 7.8) to 8-10 minutes (40.8 ± 9.3; P = .02). The mean compression depth after exertion decreased significantly (44.2 ± 8.7 at 0-2 minutes to 41.5 ± 9.1 at 8-10 minutes; P = .0008). The compression rate per minute decreased after rescue from 117.2 ±14.3 at 0 to 2 minutes to 114.1 ± 16.1 after 8 to 10 minutes (P = .002). The percentage of correct compressions at 8 to 10 minutes was identical before and after rescue (62%).nnnCONCLUSIONnIn a simulated drowning, 100 m from shore, it took twice as long to bring the patient back to shore as to reach him; and men were significantly faster. Half the participants delivered continuous chest compressions of more than 38 mm during 10 minutes of single-rescuer CPR. The quality was identical before and after surf rescue.

Outcome after out-of-hospital cardiac arrest witnessed by EMS: Changes over time and factors of importance for outcome in Sweden

BACKGROUNDnAmong patients who survive after out-of-hospital cardiac arrest (OHCA), a large proportion are recruited from cases witnessed by the Emergency Medical Service (EMS), since the conditions for success are most optimal in this subset.nnnAIMnTo evaluate outcome after EMS-witnessed OHCA in a 20-year perspective in Sweden, with the emphasis on changes over time and factors of importance.nnnMETHODSnAll patients included in the Swedish Cardiac Arrest Register from 1990 to 2009 were included.nnnRESULTSnThere were 48,349 patients and 13.5% of them were EMS witnessed. There was a successive increase in EMS-witnessed OHCA from 8.5% in 1992 to 16.9% in 2009 (p for trend<0.0001). Among EMS-witnessed OHCA, the survival to one month increased from 13.9% in 1992 to 21.8% in 2009 (p for trend<0.0001). Among EMS-witnessed OHCA, 51% were found in ventricular fibrillation, which was higher than in bystander-witnessed OHCA, despite a lower proportion with a presumed cardiac aetiology in the EMS-witnessed group. Among EMS-witnessed OHCA overall, 16.0% survived to one month, which was significantly higher than among bystander-witnessed OHCA. Independent predictors of a favourable outcome were: (1) initial rhythm ventricular fibrillation; (2) cardiac aetiology; (3) OHCA outside home and (4) decreasing age.nnnCONCLUSIONnIn Sweden, in a 20-year perspective, there was a successive increase in the proportion of EMS-witnessed OHCA. Among these patients, survival to one month increased over time. EMS-witnessed OHCA had a higher survival than bystander-witnessed OHCA. Independent predictors of an increased chance of survival were initial rhythm, aetiology, place and age.

Characteristics of lifesaving from drowning as reported by the Swedish Fire and Rescue Services 1996–2010

AIMnWe aimed to describe characteristics associated with rescue from drowning as reported by the Swedish Fire and Rescue Services (SFARS) and their association with survival from the Out of Hospital Cardiac Arrest (OHCA) registry.nnnMETHODnThis retrospective study is based on the OHCA registry and the Swedish Civil Contingencies Agency (SCCA) registry. All emergency calls (1996-2010) where the SFARS were dispatched were included (n=7175). For analysis of survival, OHCAs that matched events from the SCCA registry were included (n=250).nnnRESULTSnCalls to lakes and ponds were predominant (35% of all calls reported). Rescues were more likely in cold water, <10 °C (45%), in open water (80%) and in April-September (68%). Median delay from a call to arrival of rescue services was 8min, while it was 9 min for rescue diving units. Of all OHCA cases, the victim was found at the surface in 47% and underwater in 38%. In events where rescue divers were used, victims were significantly younger than in non-diving cardiac arrests and the mean diving depth was 6.3±5.8 m. Overall survival to one month was 5.6% (13% in diving and 4.7% in non-diving cases; p=0.07).nnnCONCLUSIONnIn half of more than 7000 drowning-related calls to the SFARS during 15 years of practice, water rescue was needed. In all treated OHCA cases, the majority were found at the surface. Only in a small percentage did rescue diving take place. In these cases, survival did not appear to be poorer than in non-diving cases.

Improving Survival and Neurologic Function for Younger Age Groups After Out-of-Hospital Cardiac Arrest in Sweden: A 20-Year Comparison.

Objective: To describe changes in the epidemiology of out-of-hospital cardiac arrest in Sweden with the emphasis on the younger age groups. Design: Prospective observational study. Setting: Sweden. Patients: Patients were recruited from the Swedish Registry of Cardiopulmonary Resuscitation from 1990 to 2012. Only non–crew-witnessed cases were included. Intervention: Cardiopulmonary resuscitation. Measurement and Main Results: The endpoint was 30-day survival. Cerebral function among survivors was estimated according to the cerebral performance category scores. In all, 50,879 patients in the survey had an out-of-hospital cardiac arrest, of which 1,321 (2.6%) were 21 years old or younger and 1,543 (3.0%) were 22–35 years old. On the basis of results from 2011 and 2012, we estimated that there are 4.9 cases per 100,000 person-years in the age group 0–21 years. The highest survival was found in the 13- to 21-year age group (12.6%). Among patients 21 years old or younger, the following were associated with an increased chance of survival: increasing age, male gender, witnessed out-of-hospital cardiac arrest, ventricular fibrillation, and a short emergency medical service response time. Among patients 21 years old or younger , there was an increase in survival from 6.2% in 1992–1998 to 14.0% in 2007–2012. Among 30-day survivors, 91% had a cerebral performance category score of 1 or 2 (good cerebral performance or moderate cerebral disability) at hospital discharge. Conclusions: In Sweden, among patients 21 years old or younger, five out-of-hospital cardiac arrests per 100,000 person-years occur and survival in this patient group has more than doubled during the past two decades. The majority of survivors have good or relatively good cerebral function.

Cardiac arrest due to drowning—Changes over time and factors of importance for survival

AIMnTo evaluate changes in characteristics and survival over time in out-of-hospital cardiac arrest (OHCA) due to drowning and describe factors of importance for survival.nnnMETHODnRetrospectively reported and treated drowning cases reported to the Swedish OHCA registry between 1990 and 2012, n=529. The data were clustered into three seven-year intervals for comparisons of changes over time.nnnRESULTSnThere were no changes in age, gender, witnessed status, shockable rhythm or place of OHCA during the time periods. Bystander CPR increased over time, 59% in interval 1992-1998, versus 74% in interval 2006-2012 (p=0.005). There was a decrease in delay between OHCA and calling for the Emergency Medical Service (EMS) over the years, while calling for the EMS to arrival increased in terms of time. Survival to hospital admission appears to have increased over the years (p=0.009), whereas survival to one month did not change significantly over time. In a multivariate analysis, witnessed status, female gender, bystander CPR, place-home and EMS response time were associated with survival to hospital admission. For survival to one month, place, age, shockable rhythm and logarithmised delay from calling for an ambulance to arrival were of significance for survival.nnnCONCLUSIONnIn OHCA due to drowning, over a period of 20 years, bystanders have called for help at an earlier stage and administered CPR more frequently in the past few years. Survival to hospital admission has increased, while shockable rhythm and early arrival of the EMS appear to be the most important factors for survival to one month.

Cardiac disease and probable intent after drowning

AIMnThe aim of this study is to determine the prevalence of cardiac disease and its relationship to the victims probable intent among patients with cardiac arrest due to drowning.nnnMETHODnRetrospective autopsied drowning cases reported to the Swedish National Board of Forensic Medicine between 1990 and 2010 were included, alongside reported and treated out-of-hospital cardiac arrests due to drowning from the Swedish Out of Hospital Cardiac Arrest Registry that matched events in the National Board of Forensic Medicine registry (n = 272).nnnRESULTSnOf 2166 drowned victims, most (72%) were males; the median age was 58 years (interquartile range, 42-71 years). Drowning was determined to be accidental in 55%, suicidal in 28%, and murder in 0.5%, whereas the intent was unclear in 16%. A contributory cause of death was found in 21%, and cardiac disease as a possible contributor was found in 9% of all autopsy cases. Coronary artery sclerosis (5%) and myocardial infarction (2%) were most frequent. Overall, cardiac disease was found in 14% of all accidental drownings, as compared with no cases (0%) in the suicide group; P = .05. Ventricular fibrillation was found to be similar in both cardiac and noncardiac cases (7%). This arrhythmia was found in 6% of accidents and 11% of suicides (P = .23).nnnCONCLUSIONnAmong 2166 autopsied cases of drowning, more than half were considered to be accidental, and less than one-third, suicidal. Among accidents, 14% were found to have a cardiac disease as a possible contributory factor; among suicides, the proportion was 0%. The low proportion of cases showing ventricular fibrillation was similar, regardless of the presence of a cardiac disease.

Higher survival rates in exercise-related out-of-hospital cardiac arrests, compared to non-exercise-related – a study from the Swedish Register of Cardiopulmonary Resuscitation

Background Despite the positive effects of physical activity, the risk of sudden cardiac arrest is transiently increased during and immediately after exercise. The purpose of this study was to assess the incidence of exercise-related out-of-hospital cardiac arrest in the general population and to compare characteristics and prognosis of these cardiac arrests with non-exercise-related out-of-hospital cardiac arrests. Methods Data from all cases of treated out-of-hospital cardiac arrest outside of home reported to the Swedish Register of Cardiopulmonary Resuscitation from 2011–2015 in three counties of Sweden were investigated (population 2.1u2009m). This registry captures almost 100% of all out-of-hospital cardiac arrests in Sweden. Results Of 1825 out-of hospital cardiac arrests, 137 (7.5%) were exercise-related, resulting in an incidence of 1.2 per 100,000 person-years. The 30-day survival rate was significantly higher among exercise-related out-of hospital cardiac arrests compared to non-exercise-related out-of-hospital cardiac arrests (54.3 % vs 19.4%, pu2009<u20090.0001). Patients suffering an exercise-related out-of-hospital cardiac arrest were on average 10 years younger than those who had a non-exercise-related out-of-hospital cardiac arrest, 56.4 years compared to 67.2 years. Exercise-related out-of-hospital cardiac arrests were more often witnessed (89.4% vs 78.6%, pu2009=u20090.002), had higher rates of bystander cardiopulmonary resuscitation (80.3% vs 61.0%, pu2009<u20090.0001) and were more frequently connected to an automated external defibrillator (20.4% vs 4.6%, pu2009<u20090.0001). Conclusions Cardiac arrests that occur in relation to exercise have a significantly better prognosis and outcome than non-exercise-related cardiac arrests. This may be explained by favourable circumstances but may also reflect that these persons experience a sudden cardiac arrest at a lower degree of coronary artery disease, due to their younger age and to exercise being a trigger.

Epidemiology of cardiac arrest outside and inside hospital experiences from registries in Sweden.

Cardiac arrest is a dramatic condition leading to sudden death if someone cannot perform two interventions, basic life sup-port and early defibrillation, that have been proved to improve long-term survival. The ‘Utstein style’, recently introduced, represents a standard of practice both inside and outside hospital with recommended guidelines for the uniform reporting of clinical data from the patient suffering cardiac arrest. In Sweden the vast majority of patients suffering from cardiac arrest regardless whether inside or outside hospital are included in webbased national registers (one for out-of-hospital cardiac arrest (OHCA) and one for in-hospital-cardiac arrest (IHCA)). In this article we will present our experiences from OHCA and IHCA separately.