Jacob Hollenberg

Early Cardiopulmonary Resuscitation in Out-of-Hospital Cardiac Arrest

BACKGROUND Three million people in Sweden are trained in cardiopulmonary resuscitation (CPR). Whether this training increases the frequency of bystander CPR or the survival rate among persons who have out-of-hospital cardiac arrests has been questioned. METHODS We analyzed a total of 30,381 out-of-hospital cardiac arrests witnessed in Sweden from January 1, 1990, through December 31, 2011, to determine whether CPR was performed before the arrival of emergency medical services (EMS) and whether early CPR was correlated with survival. RESULTS CPR was performed before the arrival of EMS in 15,512 cases (51.1%) and was not performed before the arrival of EMS in 14,869 cases (48.9%). The 30-day survival rate was 10.5% when CPR was performed before EMS arrival versus 4.0% when CPR was not performed before EMS arrival (P<0.001). When adjustment was made for a propensity score (which included the variables of age, sex, location of cardiac arrest, cause of cardiac arrest, initial cardiac rhythm, EMS response time, time from collapse to call for EMS, and year of event), CPR before the arrival of EMS was associated with an increased 30-day survival rate (odds ratio, 2.15; 95% confidence interval, 1.88 to 2.45). When the time to defibrillation in patients who were found to be in ventricular fibrillation was included in the propensity score, the results were similar. The positive correlation between early CPR and survival rate remained stable over the course of the study period. An association was also observed between the time from collapse to the start of CPR and the 30-day survival rate. CONCLUSIONS CPR performed before EMS arrival was associated with a 30-day survival rate after an out-of-hospital cardiac arrest that was more than twice as high as that associated with no CPR before EMS arrival. (Funded by the Laerdal Foundation for Acute Medicine and others.).

Improved survival after out-of-hospital cardiac arrest is associated with an increase in proportion of emergency crew--witnessed cases and bystander cardiopulmonary resuscitation.

Background— Out-of-hospital cardiac arrest (OHCA) is a major public health problem. We sought to describe changes in 1-month survival after OHCA in patients given cardiopulmonary resuscitation (CPR) during the last 14 years in Sweden. Methods and Results— All patients experiencing OHCA in whom CPR was attempted between 1992 and 2005 and who were reported to the Swedish Cardiac Arrest Register were included in the study. In all, 38 646 patients were included in this survey. The proportion of patients who were admitted alive to a hospital increased from 15.3% in 1992 to 21.7% in 2005 (P for trend <0.0001). The corresponding values for patients being alive after 1 month were 4.8% and 7.3%, respectively (P for trend <0.0001). The increase in 1-month survival was particularly evident among patients found with a shockable rhythm (increase from 12.7% in 1992 to 22.3% in 2005; P for trend <0.0001). The corresponding figures for patients found with a nonshockable rhythm were 1.2% in 1992 and 2.3% in 2005 (P for trend=0.044). Factors that potentially contributed to the improved survival rate were an increase in emergency medical crew–witnessed cases from 9% in 1992 to 15% in 2005 (P for trend <0.0001) and, to a lesser degree, an increase in bystander CPR from 31% in 1992 to 50% in 2005 (P for trend <0.0001). After adjustment for potential risk factors, the increase in survival remained significant. Conclusions— We found a significant increase in survival after OHCA in Sweden over the last 14 years. The increase was particularly marked among patients found with a shockable rhythm and was associated with an increase in the proportion of crew-witnessed cases and, to a lesser degree, an increase in the performance of bystander CPR.

Survival Is Similar After Standard Treatment and Chest Compression Only in Out-of-Hospital Bystander Cardiopulmonary Resuscitation

Background— We sought to compare the 1-month survival rates among patients after out-of-hospital cardiac arrest who had been given bystander cardiopulmonary resuscitation (CPR) in relation to whether they had received standard CPR with chest compression plus mouth-to-mouth ventilation or chest compression only. Methods and Results— All patients with out-of-hospital cardiac arrest who received bystander CPR and who were reported to the Swedish Cardiac Arrest Register between 1990 and 2005 were included. Crew-witnessed cases were excluded. Among 11 275 patients, 73% (n=8209) received standard CPR, and 10% (n=1145) received chest compression only. There was no significant difference in 1-month survival between patients who received standard CPR (1-month survival=7.2%) and those who received chest compression only (1-month survival=6.7%). Conclusions— Among patients with out-of-hospital cardiac arrest who received bystander CPR, there was no significant difference in 1-month survival between a standard CPR program with chest compression plus mouth-to-mouth ventilation and a simplified version of CPR with chest compression only.

Mobile-Phone Dispatch of Laypersons for CPR in Out-of-Hospital Cardiac Arrest

BACKGROUND Cardiopulmonary resuscitation (CPR) performed by bystanders is associated with increased survival rates among persons with out-of-hospital cardiac arrest. We investigated whether rates of bystander-initiated CPR could be increased with the use of a mobile-phone positioning system that could instantly locate mobile-phone users and dispatch lay volunteers who were trained in CPR to a patient nearby with out-of-hospital cardiac arrest. METHODS We conducted a blinded, randomized, controlled trial in Stockholm from April 2012 through December 2013. A mobile-phone positioning system that was activated when ambulance, fire, and police services were dispatched was used to locate trained volunteers who were within 500 m of patients with out-of-hospital cardiac arrest; volunteers were then dispatched to the patients (the intervention group) or not dispatched to them (the control group). The primary outcome was bystander-initiated CPR before the arrival of ambulance, fire, and police services. RESULTS A total of 5989 lay volunteers who were trained in CPR were recruited initially, and overall 9828 were recruited during the study. The mobile-phone positioning system was activated in 667 out-of-hospital cardiac arrests: 46% (306 patients) in the intervention group and 54% (361 patients) in the control group. The rate of bystander-initiated CPR was 62% (188 of 305 patients) in the intervention group and 48% (172 of 360 patients) in the control group (absolute difference for intervention vs. control, 14 percentage points; 95% confidence interval, 6 to 21; P<0.001). CONCLUSIONS A mobile-phone positioning system to dispatch lay volunteers who were trained in CPR was associated with significantly increased rates of bystander-initiated CPR among persons with out-of-hospital cardiac arrest. (Funded by the Swedish Heart-Lung Foundation and Stockholm County; ClinicalTrials.gov number, NCT01789554.).

Increase in survival and bystander CPR in out-of-hospital shockable arrhythmia: bystander CPR and female gender are predictors of improved outcome. Experiences from Sweden in an 18-year perspective

Objectives In a national perspective, to describe survival among patients found in ventricular fibrillation or pulseless ventricular tachycardia witnessed by a bystander and with a presumed cardiac aetiology and answer two principal questions: (1) what are the changes over time? and (2) which are the factors of importance? Design Observational register study. Setting Sweden. Patients All patients included in the Swedish Out of Hospital Cardiac Arrest Register between 1 January 1990 and 31 December 2009 who were found in bystander-witnessed ventricular fibrillation with a presumed cardiac aetiology. Interventions Bystander cardiopulmonary resuscitation (CPR) and defibrillation. Main outcome measures Survival to 1 month. Results In all, 7187 patients fulfilled the set criteria. Age, place of out-of-hospital cardiac arrest (OHCA) and gender did not change. Bystander CPR increased from 46% to 73%; 95% CI for OR 1.060 to 1.081 per year. The median delay from collapse to defibrillation increased from 12 min to 14 min (p for trend 0.0004). Early survival increased from 28% to 45% (95% CI 1.044 to 1.065) and survival to 1 month increased from 12% to 23% (95% CI 1.058 to 1.086). Strong predictors of early and late survival were a short interval from collapse to defibrillation, bystander CPR, female gender and OHCA outside the home. Conclusion In a long-term perspective in Sweden, survival to 1 month after ventricular fibrillation almost doubled. This was associated with a marked increase in bystander CPR. Strong predictors of outcome were a short delay to defibrillation, bystander CPR, female gender and place of collapse.

Dispatcher-assisted telephone-guided cardiopulmonary resuscitation: an underused lifesaving system.

Objectives Our purpose with this investigation was to (i) estimate how often telephone-guided cardiopulmonary resuscitation was offered from emergency medical service dispatchers in Stockholm, (ii) study the willingness to perform cardiopulmonary resuscitation, and (iii) assess factors that could mislead the dispatcher in identifying the patient as a cardiac arrest victim. Methods In this prospective study, 313 consecutive emergency calls of out-of-hospital cardiac arrest were obtained from the Swedish Cardiac Arrest Register. Seventy-six cases of out-of-hospital cardiac arrest fulfilled the inclusion criteria. All alarm calls were tape-recorded and analyzed according to a standardized protocol. Results Dispatchers offered bystanders telephone instructions for cardiopulmonary resuscitation in 47% (n=36) of the cases and, among these, cardiopulmonary resuscitation instructions were given in 69% (n=25). Only 6% (n=2) of bystanders were not willing to perform cardiopulmonary resuscitation. Signs of breathing (suspected agonal breathing) were described in 45% of the cases. Cardiopulmonary resuscitation was offered to 23% (n=10) of patients with signs of breathing versus 92% (n=23) of those who were not breathing (P<0.001). Conclusions Despite the fact that the vast majority of bystanders are willing to take part in telephone-guided cardiopulmonary resuscitation, emergency medical service dispatchers offer telephone-guided cardiopulmonary resuscitation in about only half of cases. Signs of breathing (agonal breathing) are often mistaken for normal breathing and are a cause of delay in the diagnosis of cardiac arrest.

Tuition of emergency medical dispatchers in the recognition of agonal respiration increases the use of telephone assisted CPR.

OBJECTIVES Bystanders cardiopulmonary resuscitation (CPR) increases survival in out-of-hospital cardiac arrest (OHCA). Emergency medical dispatchers (EMDs) can provide even totally inexperienced bystanders with instructions by telephone on how to resuscitate victims (T-CPR) until the emergency medical services (EMS) arrive. Agonal respiration makes it difficult for EMDs to identify cardiac arrests (CAs) which will prevent or delay initiation of T-CPR. The aim of this investigation was to study if tuition of EMDs can improve their ability to identify agonal respiration in OHCA to allow for more frequent offers of T-CPR. METHODS An observational study was made in 2004 and subsequently, a repeat study was made in 2006. All OHCA (n=315 in 2004, n=255 in 2006) in the Stockholm region reported to the Swedish Cardiac Arrest Register were included and all corresponding EMS reports were reviewed. Emergency calls were recorded during the event. Witnessed cases of OHCA (n=76 in both 2004 and 2006) were analyzed using a structured data collection tool. RESULTS The frequency of offered T-CPR to all bystanders of OHCA in 2004 was 47%. After special tuition on agonal respiration in OHCA it rose to 68% in 2006 (p=0.01). An even more marked rise was observed in OHCA cases with agonal respiration. In 2004 T-CPR was offered in 23% of these situations whereas the corresponding figures in 2006 had risen to 56% (p=0.006). CONCLUSIONS Teaching EMDs to understand and recognize bystander descriptions of agonal respiration in patients with OHCA has resulted in a significant increase in offers of T-CPR in these situations.

Mobile phone technology identifies and recruits trained citizens to perform CPR on out-of-hospital cardiac arrest victims prior to ambulance arrival

AIM In a two-parted study, evaluate a new concept were mobile phone technology is used to dispatch lay responders to nearby out-of-hospital cardiac arrests (OHCAs). METHODS Mobile phone positioning systems (MPS) can geographically locate selected mobile phone users at any given moment. A mobile phone service using MPS was developed and named Mobile Life Saver (MLS). Simulation study: 25 volunteers named mobile responders (MRs) were connected to MLS. Ambulance time intervals from 22 consecutive OHCAs in 2005 were used as controls. The MRs randomly moved in Stockholm city centre and were dispatched to simulated OHCAs (identical to controls) if they were within a 350 m distance. Real life study: during 25 weeks 1271-1801 MRs trained in CPR were connected to MLS. MLS was activated at the dispatch centre in parallel with ambulance dispatch when an OHCA was suspected. The MRs were dispatched if they were within 500 m from the suspected OHCA. RESULTS Simulation study: mean response time for the MRs compared to historical ambulance time intervals was reduced by 2 min 20s (44%), p<0.001, (95% CI, 1 min 5s - 3 min 35s). The MRs reached the simulated OHCA prior to the historical control in 72% of cases. Real life study: the MLS was triggered 92 times. In 45% of all suspected and in 56% of all true OHCAs the MRs arrived prior to ambulance. CPR was performed by MRs in 17% of all true OHCAs and in 30% of all true OHCAs if MRs arrived prior to ambulance. CONCLUSION Mobile phone technology can be used to identify and recruit nearby CPR-trained citizens to OHCAs for bystander CPR prior to ambulance arrival.

Out of hospital cardiac arrest outside home in Sweden, change in characteristics, outcome and availability for public access defibrillation

BackgroundA large proportion of patients who suffer from out of hospital cardiac arrest (OHCA) outside home are theoretically candidates for public access defibrillation (PAD). We describe the change in characteristics and outcome among these candidates in a 14 years perspective in Sweden.MethodsAll patients who suffered an OHCA in whom cardiopulmonary resuscitation (CPR) was attempted between 1992 and 2005 and who were included in the Swedish Cardiac Arrest Register (SCAR). We included patients in the survey if OHCA took place outside home excluding crew witnessed cases and those taken place in a nursing home.Results26% of all OHCAs (10133 patients out of 38710 patients) fulfilled the inclusion criteria. Within this group, the number of patients each year varied between 530 and 896 and the median age decreased from 68 years in 1992 to 64 years in 2005 (p for trend = 0.003). The proportion of patients who received bystander CPR increased from 47% in 1992 to 58% in 2005 (p for trend < 0.0001). The proportion of patients found in ventricular fibrillation (VF) declined from 56% to 50% among witnessed cases (p for trend < 0.0001) and a significant (p < 0.0001) decline was also seen among non witnessed cases.The median time from cardiac arrest to defibrillation among witnessed cases was 12 min in 1992 and 10 min in 2005 (p for trend = 0.029). Survival to one month among all patients increased from 8.1% to 14.0% (p for trend = 0.01). Among patients found in a shockable rhythm survival increased from 15.3% in 1992 to 27.0% in 2005 (p for trend < 0.0001).ConclusionIn Sweden, there was a change in characteristics and outcome among patients who suffer OHCA outside home. Among these patients, bystander CPR increased, but the occurrence of VF decreased. One-month survival increased moderately overall and highly significantly among patients found in VF, even though the time to defibrillation changed only moderately.

Aspects on the increase in bystander CPR in Sweden and its association with outcome

AIM To describe changes in the proportion of bystanders performing cardiopulmonary resuscitation (CPR) in out of hospital cardiac arrest (OHCA) in Sweden and to study the impact of bystander CPR on ventricular fibrillation and on survival during various times. PATIENTS AND METHODS All patients who suffered from OHCA in Sweden in whom CPR was attempted and who were included in the Swedish cardiac arrest register (SCAR) between 1992 and 2005. Crew witnessed cases were excluded. RESULTS In all 34,125 patients were included in the survey. Among witnessed OHCA the proportion of patients receiving bystander CPR increased from 40% in 1992 to 55% in 2005 (p<0.0001). In non-witnessed OHCA the corresponding proportion increased from 22% to 44% (p<0.0001). There was a significant increase in bystander CPR regardless of age, sex and place. The increase was only found when CPR was performed by lay persons (21% in 1992 to 40% in 2005; p<0.0001). Bystander CPR was associated with an increased proportion of patients found in a shockable rhythm and a lower number of shocks to receive return of spontaneous circulation. Bystander CPR was associated with a similar increase in survival early and late in the evaluation. CONCLUSION There was a marked increase in bystander CPR in OHCA, when performed by lay persons, during the last 14 years in Sweden. Bystander CPR was associated with positive effects both on ventricular fibrillation and survival.