Abstract Purpose Out-of-hospital cardiac arrest (OHCA) is a major cause of death in the United States. How individual-level socioeconomic status (SES) influences survival is uncertain. Methods The ...investigation is a retrospective cohort study of adults who suffered OHCA and presented with a shockable rhythm in a metropolitan county from January 1, 1999–December 31, 2005. Individual-level measures of SES were obtained from vital records and surveys. SES measures included education and occupation. We used multivariable logistic regression to assess the independent association between SES measures and survival to hospital discharge. Results Of the 1390 eligible OHCA patients, 374 (27%) survived to hospital discharge. Compared to those with less than high school diploma, the multivariable-adjusted odds ratio of survival was 1.36 (95% confidence interval CI, 0.87–2.14) for high school graduates, 1.54 (95% CI, 0.95–2.48) for those with some college, and 1.96 (95% CI, 1.17–3.27) for those with college degrees (test for trend across the categories P < .001). We did not observe an independent association between occupation and survival. Conclusions Higher education was associated with greater survival after OHCA. This relationship was not explained by key demographic or clinical characteristics. A better understanding of the mechanism by which individual-level SES characteristics influence prognosis may provide opportunities to improve survival.
Abstract Background Bystander cardiopulmonary resuscitation (CPR) is associated with a greater likelihood of survival to hospital discharge after out-of-hospital cardiac arrest (OHCA). However the ...long-term survival benefits in relationship to cost have not been well-studied. We evaluated bystander CPR, hospital-based costs, and long-term survival following OHCA in order to assess the potential cost-effectiveness of bystander CPR. Patients and methods We conducted a retrospective cohort study of consecutive EMS-treated OHCA patients > = 12 years who arrested prior to EMS arrival and outside a nursing facility between 2001 and 2010 in greater King County, WA. Utstein-style information was obtained from the EMS registry, including 5-year survival. Costs from the OHCA hospitalization were obtained from the Washington State Comprehensive Hospital Abstract Reporting System. Cost effectiveness was based on hospital costs divided by quality-adjusted life years (QALYs) for a 5-year follow-up window. Results Of the 4448 eligible patients, 18.5% (n = 824) were discharged alive from hospital and 12.1% (n = 539) were alive at 5 years. Five-year survival was higher in patients who received bystander CPR (14.3% vs. 8.7%, p < 0.001) translating to an average 0.09 QALYs associated with bystander CPR. The average (SD) total cost of the initial acute care hospitalization was USD 19,961 (40,498) for all admitted patients and USD 75,175 (52,276) for patients alive at year 5. The incremental cost-effectiveness ratio associated with bystander CPR was USD 48,044 per QALY. Conclusion Based on this population-based investigation, bystander CPR was positively associated with long-term survival and appears cost-effective.
The objective of this study was to test the effectiveness of simulation training, using actors to make mock calls, on improving Emergency Medical Dispatchers’ (EMDs) ability to recognize the need ...for, and reduce the time to, telephone-assisted CPR (T-CPR) in simulated and real cardiac arrest 9-1-1 calls.
We conducted a parallel prospective randomized controlled trial with n=157 EMDs from thirteen 9-1-1 call centers. Study participants were randomized within each center to intervention (i.e., completing 4 simulation training sessions over 12-months) or control (status quo). After the intervention period, performance on 9 call processing skills and 2 time-intervals were measured in 2 simulation assessment calls for both arms. Six of the 13 call centers provided recordings of real cardiac arrest calls taken by study participants during the study period.
Of the N=128 EMDs who completed the simulation assessment, intervention participants (n=66) performed significantly better on 6 of 9 call processing skills and started T-CPR 23s faster (73 vs 91s respectively, p<0.001) compared to participants in the control arm (n=62). In real cardiac arrest calls, EMDs who completed 3 or 4 training sessions were more likely to recognize the need for T-CPR for more challenging cardiac arrest calls than EMDs who completed fewer than 3, including controls who completed no training (68% vs 53%, p=0.018).
Simulation training improves call processing skills and reduces time to T-CPR in simulated call scenarios, and may improve the recognition of the need for T-CPR in more challenging real-life cardiac arrest calls.
http://www.clinicaltrials.gov Trial # NCT01972087.
Background Bystander cardiopulmonary resuscitation (CPR) is a critical intervention to improve survival following out-of-hospital cardiac arrest. We evaluated the quality of bystander CPR and whether ...performance varied according to the number of bystanders or provision of telecommunicator CPR (TCPR). Methods and Results We investigated non-traumatic out-of-hospital cardiac arrest occurring in a large metropolitan emergency medical system during a 6-month period. Information about bystander care was ascertained through review of the 9-1-1 recordings in addition to emergency medical system and hospital records to determine bystander CPR status (none versus TCPR versus unassisted), the number of bystanders on-scene, and CPR performance metrics of compression fraction and compression rate. Of the 428 eligible out-of-hospital cardiac arrest, 76.4% received bystander CPR including 43.7% unassisted CPR and 56.3% TCPR; 35.2% had one bystander, 33.3% had 2 bystanders, and 31.5% had ≥3 bystanders. Overall compression fraction was 59% with a compression rate of 88 per minute. CPR differed according to TCPR status (fraction=52%, rate=87 per minute for TCPR versus fraction=69%, rate=102 for unassisted CPR,
<0.05 for each comparison) and the number of bystanders (fraction=55%, rate=87 per minute for 1 bystander, fraction=59%, rate=89 for 2 bystanders, fraction=65%, rate=97 for ≥3 bystanders, test for trend
<0.05 for each metric). Additional bystander actions were uncommon to include rotation of compressors (3.1%) or application of an automated external defibrillator (8.0%). Conclusions Bystander CPR quality as gauged by compression fraction and rate approached guideline goals though performance depended upon the type of CPR and number of bystanders.
CONTEXT Recent reports from 2 European cities and an earlier observation from
Seattle, Wash, suggest that the number of patients treated for out-of-hospital
ventricular fibrillation (VF) has ...declined. OBJECTIVE To analyze the incidence of cardiac arrest and to examine relationships
among incidence, sex, race, age, and first identified cardiac rhythm in Seattle. DESIGN, SETTING, AND PATIENTS Population-based study of all cardiac arrest cases with presumed cardiac
etiology who received advanced life support from Seattle Fire Department emergency
medical services during specified periods between 1979 and 2000. United States
Census data for Seattle in 1980, 1990, and 2000 were used to determine incidence
rates for treated cardiac arrest with adjustments for age and sex. MAIN OUTCOME MEASURES Changes in incidence of cardiac arrest and initial recorded cardiac
rhythm. RESULTS The adjusted annual incidence of cardiac arrest with VF as the first
identified rhythm decreased by about 56% from 1980 to 2000 (from 0.85 to 0.38
per 1000; relative risk RR, 0.44; 95% confidence interval CI, 0.37-0.53).
Similar reductions occurred in blacks (54%; RR, 0.45; 95% CI, 0.26-0.79) and
whites (53%; RR, 0.47; 95% CI, 0.38-0.58) and was most evident in men (57%;
RR, 0.43; 95% CI, 0.35-0.53), in whom the baseline incidence was relatively
high. When all treated arrests with presumed cardiac etiology were considered,
that incidence decreased by 43% (RR, 0.58; 95% CI, 0.49-0.67) in men but negligibly
in women, for whom a relatively low incidence of VF also declined but was
offset by more cases with asystole or pulseless electrical activity. CONCLUSION We observed a major decline in the incidence of out-of-hospital VF and
in all cases of treated cardiac arrest presumably due to heart disease in
Seattle. These changes likely reflect the national decline in coronary heart
disease mortality.
Quantitative measures of the ventricular fibrillation waveform at the outset of resuscitation are associated with survival. However, little is known about the course of these measures during ...resuscitation and how this course is related to outcome.
The purpose of this study was to determine how waveform measures change over the course of resuscitation and whether these changes might be used to guide resuscitation.
We evaluated 390 persons treated by emergency providers following out-of-hospital ventricular fibrillation arrest. We assessed the ventricular fibrillation waveform using the amplitude spectrum area (AMSA) from the defibrillator's continuous electrocardiogram measured before each of the first three shocks. We used logistic regression to evaluate the relationship of AMSA and the change in AMSA with favorable neurologic survival as determined by the Cerebral Performance Category at hospital discharge 1-2.
Of the 390 patients who received an initial shock, 273 required a second shock and 210 required a third shock. The mean (standard deviation) for AMSA was 9.64 (0.52) for the 873 total shock cycles. AMSA₁ measured before the first shock was strongly associated with favorable neurologic survival (odds ratio OR 3.40, 95% confidence interval CI 2.48, 4.66 for 1 SD change). We observed a similar relationship for second-shock AMSA₂ (OR 3.53, 95% CI 2.42, 5.14) and third-shock AMSA₃ (OR 3.10, 95% CI 2.03, 4.73). The median change in AMSA was 0.24 for ΔAMSA₁₋₂ and 0.21 for ΔAMSA₂₋₃. A positive median change in AMSA between shocks was associated with favorable neurologic survival (OR 1.44, 95% CI 1.16, 1.80 for ΔAMSA₁₋₂ and OR 1.31, 95% CI 1.01, 1.71 for ΔAMSA₂₋₃).
Given their prognostic and dynamic qualities, quantitative waveform measures may provide an effective real-time strategy to guide individual treatment and improve survival.
The incidence of sudden cardiac death is roughly 3 times greater in men than in women. However, in patients treated for out-of-hospital cardiac arrest, the relationships between sex and survival ...after adjustment for age and cardiac rhythm are unclear.
In this retrospective cohort study, we examined 7069 men and 2582 women who were treated for out-of-hospital cardiac arrest in Seattle and suburban King County between 1990 and 1998. We compared successful prehospital resuscitation (hospital admission) and survival from event to discharge in men and women. Women had markedly reduced rates of ventricular fibrillation (VF), slightly older age, fewer witnessed arrests, and fewer arrests in public locations than men. Although their unadjusted resuscitation rate was lower (29% versus 32%, P<0.0001), women had a greater likelihood of resuscitation than men after adjustment for VF (odds ratio OR 1.13; 95% confidence interval CI, 1.03 to 1.25) and after adjustment for VF plus additional factors (OR, 1.27; 95% CI, 1.14 to 1.41). The difference in resuscitation rates between men and women decreased as they aged (test for trend, P<0.0001). Unadjusted survival rates were also lower in women than in men (11% versus 15%, P<0.0001). Women had similar survival after adjustment for VF (OR, 0.97; 95% CI, 0.85 to 1.11) and after adjustment for VF plus additional factors (OR, 1.09; 95% CI, 0.93 to 1.27).
The lower unadjusted resuscitation and survival rates observed in women were primarily due to women's lower incidence of VF, a relatively favorable cardiac rhythm. After adjustment for VF and other factors, women had higher resuscitation rates than men, but similar rates of survival from event to discharge.
Abstract Aim We examined the relationship between time from collapse to arrival of emergency medical services (EMS) and survival to hospital discharge for out-of-hospital ventricular fibrillation ...cardiac arrests in order to determine meaningful interpretations of this association. Methods We calculated survival rates in 1-min intervals from collapse to EMS arrival. Additionally, we used logistic regression to determine the absolute probability of survival per minute of delayed EMS arrival. We created a logistic regression model with spline terms for the time variable to examine the decline in survival in intervals that are hypothesized to be physiologically relevant. Results The observed data showed survival declined, on average, by 3% for each minute that EMS was delayed following collapse. Survival rates did not decline appreciably if the time between collapse and arrival of EMS was 4 min or less but they declined by 5.2% per minute between 5 and 10 min. EMS arrival 11–15 min after collapse showed a less steep decline in survival of 1.9% per minute. The spline model that incorporated changes in slope in the time interval variable modeled this relationship more accurately than a model with a continuous term for time ( p = 0.01). Conclusions The results of our analyses show that survival from out-of-hospital cardiac arrest does not decline at a constant rate following collapse. Models that incorporate changes that reflect the physiological alterations that occur following cardiac arrests are a more accurate way to describe changes in survival rates over time than models that include only a continuous term for time.
Out-of-hospital cardiac arrest (OHCA) claims millions of lives worldwide each year. OHCA survival from shockable arrhythmias (ventricular fibrillation/ tachycardia) improved in several communities ...after implementation of American Heart Association resuscitation guidelines that eliminated "stacked" shocks and emphasized chest compressions. "Nonshockable" rhythms are now the predominant presentation of OHCA; the benefit of such treatments on nonshockable rhythms is uncertain.
We studied 3960 patients with nontraumatic OHCA from nonshockable initial rhythms treated by prehospital providers in King County, Washington, over a 10-year period. Outcomes during a 5-year intervention period after adoption of new resuscitation guidelines were compared with the previous 5-year historical control period. The primary outcome was 1-year survival. Patient demographics and resuscitation characteristics were similar between the control (n=1774) and intervention (n=2186) groups, among whom 471 of 1774 patients (27%) versus 742 of 2186 patients (34%), respectively, achieved return of spontaneous circulation; 82 (4.6%) versus 149 (6.8%) were discharged from hospital, 60 (3.4%) versus 112 (5.1%) with favorable neurological outcome; 73 (4.1%) versus 135 (6.2%) survived 1 month; and 48 (2.7%) versus 106 patients (4.9%) survived 1 year (all P≤0.005). After adjustment for potential confounders, the intervention period was associated with an improved odds of 1.50 (95% confidence interval, 1.29-1.74) for return of spontaneous circulation, 1.53 (95% confidence interval, 1.14-2.05) for hospital survival, 1.56 (95% confidence interval, 1.11-2.18) for favorable neurological status, 1.54 (95% confidence interval, 1.14-2.10) for 1-month survival, and 1.85 (95% confidence interval, 1.29-2.66) for 1-year survival.
Outcomes from OHCA resulting from nonshockable rhythms, although poor by comparison with shockable rhythm presentations, improved significantly after implementation of resuscitation guideline changes, suggesting their potential to benefit all presentations of OHCA.
Background
The HeartRescue Project is a multistate public health initiative focused on establishing statewide out‐of‐hospital cardiac arrest (OHCA) systems of care to improve case capture and OHCA ...care in the community, by emergency medical services (EMS), and at hospital level.
Methods and Results
From 2011 to 2015 in the 5 original HeartRescue states, all adults with EMS–treated OHCA due to a presumed cardiac cause were included. In an adult population of 32.8 million, a total of 64 988 OHCAs—including 10 046 patients with a bystander‐witnessed OHCA with a shockable rhythm—were treated by 330 EMS agencies. From 2011 to 2015, the case‐capture rate for all‐rhythm OHCA increased from an estimated 39.0% (n=6762) to 89.2% (n=16 103; P<0.001 for trend). Overall survival to hospital discharge was 11.4% for all rhythms and 34.0% in the subgroup with bystander‐witnessed OHCA with a shockable rhythm. We observed modest temporal increases in bystander cardiopulmonary resuscitation (41.8–43.5%, P<0.001 for trend) and bystander automated external defibrillator application (3.2–5.6%, P<0.001 for trend) in the all‐rhythm group, although there were no temporal changes in survival. There were marked all‐rhythm survival differences across the 5 states (8.0–16.1%, P<0.001) and across participating EMS agencies (2.7–26.5%, P<0.001).
Conclusions
In the initial 5 years, the HeartRescue Project developed a population‐based OHCA registry and improved statewide case‐capture rates and some processes of care, although there were no early temporal changes in survival. The observed survival variation across states and EMS systems presents a future challenge to elucidate the characteristics of high‐performing systems with the goal of improving OHCA care and survival.