Esophageal temperature after out-of-hospital cardiac arrest: An observational study

Introduction

Out-of-hospital cardiac arrest (OHCA) is a significant cause of death and severe neurological disability. The only post-return of spontaneous circulation (ROSC) therapy shown to increase survival is mild therapeutic hypothermia (MTH). The relationship between esophageal temperature post OHCA and outcome is still poorly defined.

Methods

Prospective observational study of all OHCA patients admitted to a single centre for a 14-month period (1/08/2008 to 31/09/2009). Esophageal temperature was measured in the Emergency Department and Intensive Care Unit (ICU). Selected patients had pre-hospital temperature monitoring. Time taken to reach target temperature after ROSC was recorded, together with time to admission to the Emergency Department and ICU.

Results

164 OHCA patients were included in the study. 105 (64.0%) were pronounced dead in the Emergency Department. 59 (36.0%) were admitted to ICU for cooling; 40 (24.4%) died in ICU and 19 (11.6%) survived to hospital discharge. Patients who achieved ROSC and had esophageal temperature measured pre-hospital (n = 29) had a mean pre-hospital temperature of 33.9 °C (95% CI 33.2-34.5). All patients arriving in the ED post OHCA had a relatively low esophageal temperature (34.3 °C, 95% CI 34.1-34.6). Patients surviving to hospital discharge were warmer on admission to ICU than patients who died in hospital (35.7 °C vs 34.3 °C, p < 0.05). Patients surviving to hospital discharge also took longer to reach T_targ than non-survivors (2 h 48 min vs 1 h 32 min, p < 0.05).

Conclusions

Following OHCA all patients have esophageal temperatures below normal in the pre-hospital phase and on arrival in the Emergency Department. Patients who achieve ROSC following OHCA and survive to hospital discharge are warmer on arrival in ICU and take longer to reach target MTH temperatures compared to patients who die in hospital. The mechanisms of action underlying esophageal temperature and survival from OHCA remain unclear and further research is warranted to clarify this relationship.     

Changing EMS dispatcher CPR instructions to 400 compressions before mouth-to-mouth improved bystander CPR rates

Background

To examine the impact of changing dispatcher CPR instructions (400 compressions: 2 breaths, followed by 100:2 ratio) on rates of bystander CPR and survival in adults with presumed cardiac out-of-hospital arrest (OHCA) in Melbourne, Australia.

Methods

The Victorian Ambulance Cardiac Arrest Registry (VACAR) was searched for OHCA where Emergency Medical Services (EMS) attempted CPR between August 2006 and August 2009. OHCA included were: (1) patients aged ≥18 years old; (2) presumed cardiac etiology; and (3) not witnessed by EMS.

Results

For the pre- and post-study periods, 1021 and 2101 OHCAs met inclusion criteria, respectively. Rates of bystander CPR increased overall (45-55%, p < 0.001) and by initial rhythm (shockable 55-70%, p < 0.001 and non-shockable 40-46%, p = 0.01). In VF/VT OHCA, there were improvements in the number of patients arriving at hospital with a return of spontaneous circulation (ROSC) (48-56%, p = 0.02) and in survival to hospital discharge (21-29%, p = 0.002), with improved outcomes restricted to patients receiving bystander CPR. After adjusting for factors associated with survival, the period of time following the change in CPR instructions was a significant predictor of survival to hospital discharge in VF/VT patients (OR 1.57, 95% CI: 1.15-2.20, p = 0.005).

Conclusion

Following changes to dispatcher CPR instructions, significant increases were seen in rates of bystander CPR and improvements were seen in survival in VF/VT patients who received bystander CPR, after adjusting for factors associated with survival.     

Adrenaline for out-of-hospital cardiac arrest resuscitation: A systematic review and meta-analysis of randomized controlled trials

Introduction

The evidence for adrenaline in out-of-hospital cardiac arrest (OHCA) resuscitation is inconclusive. We systematically reviewed the efficacy of adrenaline for adult OHCA.

Methods

We searched in MEDLINE, EMBASE, and Cochrane Library from inception to July 2013 for randomized controlled trials (RCTs) evaluating standard dose adrenaline (SDA) to placebo, high dose adrenaline (HDA), or vasopressin (alone or combination) in adult OHCA patients. Meta-analyses were performed using random effects modeling. Subgroup analyses were performed stratified by cardiac rhythm and by number of drug doses. The primary outcome was survival to discharge and the secondary outcomes were return of spontaneous circulation (ROSC), survival to admission, and neurological outcome.

Results

Fourteen RCTs (n = 12,246) met inclusion criteria: one compared SDA to placebo (n = 534), six compared SDA to HDA (n = 6174), six compared SDA to an adrenaline/vasopressin combination (n = 5202), and one compared SDA to vasopressin alone (n = 336). There was no survival to discharge or neurological outcome differences in any comparison group, including subgroup analyses. SDA showed improved ROSC (RR 2.80, 95%CI 1.78–4.41, p < 0.001) and survival to admission (RR 1.95, 95%CI 1.34–2.84, p < 0.001) compared to placebo. SDA showed decreased ROSC (RR 0.85, 95%CI 0.75–0.97, p = 0.02; I² = 48%) and survival to admission (RR 0.87, 95%CI 0.76–1.00, p = 0.049; I² = 34%) compared to HDA. There were no differences in outcomes between SDA and vasopressin alone or in combination with adrenaline.

Conclusions

There was no benefit of adrenaline in survival to discharge or neurological outcomes. There were improved rates of survival to admission and ROSC with SDA over placebo and HDA over SDA.     

Cardiac arrest outcomes before and after the 2005 resuscitation guidelines implementation: evidence of improvement?

Background

Previous studies have reported improvements in out-of-hospital cardiac arrest (OHCA) outcomes with the introduction of the 2005 cardiopulmonary resuscitation guidelines however they have not adjusted for underlying trends in OHCA survival. We compare outcomes before and after the 2005 guideline changes adjusting for underlying trends in OHCA survival.

Methods

The Victorian Ambulance Cardiac Arrest Registry (VACAR) was searched for adult (≥16 years) OHCA of presumed cardiac aetiology, unwitnessed by paramedics with attempted resuscitation. Outcomes for OHCA occurring between 2003 and 2005 were compared with 2007-2009. Segmented regression analysis of interrupted time series data was performed, adjusting for known predictors, to examine changes in survival to hospital and survival to hospital discharge.

Results

For the pre- and post- guideline periods there were 3115 and 3248 OHCAs, respectively. Asystole increased as presenting rhythm (33-43%, p < 0.001) as did median EMS response times (7.1-7.8 min, p < 0.001) over the two periods. VF/VT arrests decreased (40-35.5%, p = 0.001) as did bystander witnessed arrests (63-59%, p = 0.002). On univariate analysis survival to hospital discharge improved between the two periods (9.4-11.8%, p = 0.002) due to improved outcomes in VF/VT (19-28%, p < 0.001). Segmented regression analysis of interrupted time series data showed improvement in the rate of survival to get to hospital for shockable and non-shockable rhythms [OR (95% CI) = 1.54 (1.10-2.15, p = 0.01) and 1.45 (1.10-2.00, p = 0.02), respectively] following implementation of the guidelines however survival to hospital discharge did not improve [OR = 1.07 (0.70-1.62, p = 0.70) and 1.40 (0.69-2.85, p = 0.40), respectively].

Conclusions

OHCA outcomes have improved since introduction of the 2005 CPR guidelines, but multivariable segmented regression analysis adjusting for pre-existing trends in survival suggests that this improvement may not be due to implementation of the 2005 resuscitation guidelines.     

Prognostic indicators and outcome prediction model for patients with return of spontaneous circulation from cardiopulmonary arrest: the Utstein Osaka Project

Objective

To determine the most important indicators of prognosis in patients with return of spontaneous circulation (ROSC) following out-of-hospital cardiopulmonary arrest (OHCA) and to develop a best outcome prediction model.

Design and patients

All patients were prospectively recorded based on the Utstein Style in Osaka over a period of 3 years (2005-2007). Criteria for inclusion were a witnessed cardiac arrest, age greater than 17 years, presumed cardiac origin of the arrest, and successful ROSC. Multivariate logistic regression (MLR) analysis was used to develop the best prediction model. The dependent variables were favourable outcome (cerebral-performance category [CPC]: 1-2) and poor outcome (CPC: 3-5) at 1 month after the event. Eight explanatory pre-hospital variables were used concerning patient characteristics and resuscitation. External validation was performed on an independent set of Utstein data in 2007.

Results

Subjects comprised 285 patients in VF and 577 patients with pulseless electrical activity (PEA)/asystole. The percentage of favourable outcomes was 31.9% (91/285) in VF and 5.7% (33/577) in PEA/asystole. The most important prognostic indicators of favourable outcome found by MLR were age (p = 0.10), time from collapse to ROSC (TROSC) (p < 0.01), and presence of pre-hospital ROSC (PROSC) (p = 0.15) for VF and age (p = 0.03), TROSC (p < 0.01), PROSC (p < 0.01), and conversion to VF (p = 0.01) for PEA/asystole. For external validation data, areas under the receiver-operating characteristic curve were 0.867 for VF and 0.873 for PEA/asystole.

Conclusions

A model based on four selected indicators showed a high predictive value for favourable outcome in OHCA patients with ROSC.     

Pediatric out-of-hospital cardiac arrest in Korea: A nationwide population-based study

Study objectives

Our objective was to describe the incidence and demographics of pediatric out-of-hospital cardiac arrest (OHCA) in Korea.

Methods

We identified non-traumatic OHCA patients aged less than 20 years from a Korean nationwide OHCA registry (2006-2007). Data from emergency medical service (EMS) run-sheets and hospital records were reviewed. We excluded cases with unknown hospital outcomes. Patient characteristics, treatment by EMS, and outcomes were compared by age groups: infant (<1 year), children (1-11 years), and adolescents (12-19 years).

Results

A total of 971 patients including infants (n = 299, 30.8%), children (n = 305, 31.4%), and adolescents (n = 367, 37.8%) met inclusion criteria. The incidence of pediatric OHCA was 4.2 per 100,000 person-years (67.1 in infants, 2.5 in children, and 3.5 in adolescents). The rate of cardiopulmonary resuscitation administered was 82.1% (infants 80.6%, children 82.0%, and adolescent 83.4%). The rate of applying automated external defibrillators and advanced airway management (endotracheal intubation or laryngeal mask airway), was only 4.1% and 2.5%, respectively. 7.4% showed ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) in the initial ECG. Survival to hospital discharge for all pediatric OHCA was 4.9% (2.9% for infants, 4.7% for children, and 7.2% of adolescents). For EMS-treated pediatric OHCA or patients with VF or pulseless VT, the rate was 5.0% and 31.6%, respectively.

Conclusion

Incidence and hospital outcomes in pediatric OHCA in Korea were comparable to other population-based nationwide reports.     

Good outcome in every fourth resuscitation attempt is achievable--an Utstein template report from the Stavanger region

Aim of the study

Out-of-hospital cardiac arrest (OHCA) is a major cause of death in the western world. We wanted to study changes in survival over time and factors linked to this in a region which have already reported high survival rates.

Methods

We used a prospectively collected Utstein template database to identify all resuscitation attempts in adult patients with OHCA of presumed cardiac origin. We included 846 resuscitation attempts and compared survival to discharge with good outcome in two time periods (2001-2005 vs. 2006-2008).

Results

We found no significant differences between the two time periods for mean age (71 and 70 years (p = 0.309)), sex distribution (males 70% and 71% (p = 0.708)), location of the OHCA (home 64% and 63% (p = 0.732)), proportion of shockable rhythms (44% and 47% (p = 0.261)) and rate of return of spontaneous circulation (38% and 43% (p = 0.136)), respectively. Bystander cardiopulmonary resuscitation (CPR), however, increased significantly from 60% to 73% (p < 0.0001), as did the overall rate of survival to discharge from 18% to 25% (p = 0.018). In patients with a shockable first rhythm, rate of survival to discharge increased significantly from 37% to 48% (p = 0.036). In witnessed arrest with shockable rhythm survival to discharge increased from 37% to 52% (p = 0.0105).

Conclusion

Overall, good outcome is now achievable in every fourth resuscitation attempt and in every second resuscitation attempt when patients have a shockable rhythm. The reason for the better outcomes is most likely multi-factorial and linked to improvements in the local chain of survival.     

Comparing the survival between extracorporeal rescue and conventional resuscitation in adult in-hospital cardiac arrests: Propensity analysis of three-year data

Aim

Extracorporeal cardiopulmonary resuscitation (ECPR) has been shown to have survival benefit over conventional CPR (CCPR) in patients with in-hospital cardiac arrest of cardiac origin. We compared the survival of patients who had return of spontaneous beating (ROSB) after ECPR with the survival of those who had return of spontaneous circulation (ROSC) after conventional CPR.

Methods

Propensity score-matched cohort of adults with in-hospital prolonged CPR (>10 min) of cardiac origin in a university-affiliated tertiary extracorporeal resuscitation center were included in this study. Fifty-nine patients with ROSB after ECPR and 63 patients with sustained ROSC by CCPR were analyzed. Main outcome measures were survival at hospital discharge, 30 days, 6 months, and one year, and neurological outcome.

Results

There was no statistical difference in survival to discharge (29.1% of ECPR responders vs. 22.2% of CCPR responders, p = 0.394) and neurological outcome at discharge and one year later. In the propensity score-matched groups, 9 out of 27 ECPR patients survived to one month (33.3%) and 7 out of 27 CCPR patients survived (25.9%). Survival analysis showed no survival difference (HR: 0.856, p = 0.634, 95% CI: 0.453-1.620) between the groups, either at 30 days or at the end of one year (HR: 0.602, p = 0.093, 95% CI: 0.333-1.088).

Conclusions

This study failed to demonstrate a survival difference between patients who had ROSB after institution of ECMO and those who had ROSC after conventional CPR. Further studies evaluating the role of ECMO in conventional CPR rescued patients are warranted.     

Passive leg raising during cardiopulmonary resuscitation in out-of-hospital cardiac arrest—Does it improve circulation and outcome?

Background

Passive leg raising (PLR), to augment the artificial circulation, was deleted from cardiopulmonary resuscitation (CPR) guidelines in 1992. Increases in end-tidal carbon dioxide (P_ETCO₂) during CPR have been associated with increased pulmonary blood flow reflecting cardiac output. Measurements of P_ETCO₂ after PLR might therefore increase our understanding of its potential value in CPR. We also observed the alteration in P_ETCO₂ in relation to the return of spontaneous circulation (ROSC) and no ROSC.

Methods and results

The P_ETCO₂ was measured, subsequent to intubation, in 126 patients suffering an out-of-hospital cardiac arrest (OHCA), during 15 min or until ROSC. Forty-four patients were selected by the study protocol to PLR 35 cm; 21 patients received manual chest compressions and 23 mechanical compressions. The PLR was initiated during uninterrupted CPR, 5 min from the start of P_ETCO₂ measurements. During PLR, an increase in P_ETCO₂ was found in all 44 patients within 15 s (p = 0.003), 45 s (p = 0.002) and 75 s (p = 0.0001). Survival to hospital discharge was 7% among patients with PLR and 1% among those without PLR (p = 0.12). Among patients experiencing ROSC (60 of 126), we found a marked increase in P_ETCO₂ 1 min before the detection of a palpable pulse.

Conclusion

Since PLR during CPR appears to increase P_ETCO₂ after OHCA, larger studies are needed to evaluate its potential effects on survival. Further, the measurement of P_ETCO₂ could help to minimise the hands-off periods and pulse checks.     

Assessment of outcomes and differences between in- and out-of-hospital cardiac arrest patients treated with cardiopulmonary resuscitation using extracorporeal life support

Aim

Cardiopulmonary resuscitation (CPR) using extracorporeal life support (ECLS) for in-hospital cardiac arrest (IHCA) patients has been assigned a low-grade recommendation in current resuscitation guidelines. This study compared the outcomes of IHCA and out-of-hospital cardiac arrest (OHCA) patients treated with ECLS.

Methods

A total of 77 patients were treated with ECLS. Baselines characteristics and outcomes were compared for 38 IHCA and 39 OCHA patients.

Results

The time interval between collapse and starting ECLS was significantly shorter after IHCA than after OHCA (25 (21-43) min versus 59 (45-65) min, p < 0.001). The weaning rate from ECLS (61% versus 36%, p = 0.03) and 30-day survival (34% versus 13%, p = 0.03) were higher for IHCA compared with OHCA patients. IHCA patients had a higher rate of favourable neurological outcome compared to OHCA patients, but the difference was not statistically significant (26% versus 10%, p = 0.07). Kaplan-Meier analysis showed improved 30-day and 1-year survival for IHCA patients treated with ECLS compared to OHCA patients who had ECLS. However, multivariate stepwise Cox regression model analysis indicated no difference in 30-day (odds ratio 0.94 (95% confidence interval 0.68-1.27), p = 0.67) and 1-year survival (0.99 (0.73-1.33), p = 0.95).

Conclusion

CPR with ECLS led to more favourable patient outcomes after IHCA compared with OHCA in our patient group. The difference in outcomes for ECLS after IHCA and OHCA disappeared after adjusting for patient factors and the time delay in starting ECLS.     

Global incidences of out-of-hospital cardiac arrest and survival rates: Systematic review of 67 prospective studies

Aim

The aim of this investigation was to estimate and contrast the global incidence and outcome of out-of-hospital cardiac arrest (OHCA) to provide a better understanding of the variability in risk and survival of OHCA.

Methods

We conducted a review of published English-language articles about incidence of OHCA, available through MEDLINE and EmBase. For studies including adult patients and both adult and paediatric patients, we used Utstein data reporting guidelines to calculate, summarize and compare incidences per 100,000 person-years of attended OHCAs, treated OHCAs, treated OHCAs with a cardiac cause, treated OHCA with ventricular fibrillation (VF), and survival-to-hospital discharge rates following OHCA.

Results

Sixty-seven studies from Europe, North America, Asia or Australia met inclusion criteria. The weighted incidence estimate was significantly higher in studies including adults than in those including adults and paediatrics for treated OHCAs (62.3 vs 34.7; P < 0.001); and for treated OHCAs with a cardiac cause (54.6 vs 40.8; P = 0.004). Neither survival to discharge rates nor VF survival to discharge rates differed statistically significant among studies. The incidence of treated OHCAs was higher in North America (54.6) than in Europe (35.0), Asia (28.3), and Australia (44.0) (P < 0.001). In Asia, the percentage of VF and survival to discharge rates were lower (11% and 2%, respectively) than those in Europe (35% and 9%, respectively), North America (28% and 6%, respectively), or Australia (40% and 11%, respectively) (P < 0.001, P < 0.001).

Conclusions

OHCA incidence and outcome varies greatly around the globe. A better understanding of the variability is fundamental to improving OHCA prevention and resuscitation.     

The addition of voice prompts to audiovisual feedback and debriefing does not modify CPR quality or outcomes in out of hospital cardiac arrest--a prospective, randomized trial

Aims

Chest compression quality is a determinant of survival from out-of-hospital cardiac arrest (OHCA). ERC 2005 guidelines recommend the use of technical devices to support rescuers giving compressions. This prospective randomized study reviewed influence of different feedback configurations on survival and compression quality.

Materials and methods

312 patients suffering an OHCA were randomly allocated to two different feedback configurations. In the limited feedback group a metronome and visual feedback was used. In the extended feedback group voice prompts were added. A training program was completed prior to implementation, performance debriefing was conducted throughout the study.

Results

Survival did not differ between the extended and limited feedback groups (47.8% vs 43.9%, p = 0.49). Average compression depth (mean ± SD: 4.74 ± 0.86 cm vs 4.84 ± 0.93 cm, p = 0.31) was similar in both groups. There were no differences in compression rate (103 ± 7 vs 102 ± 5 min(−1), p = 0.74) or hands-off fraction (16.16% ± 0.07 to 17.04% ± 0.07, p = 0.38). Bystander CPR, public arrest location, presenting rhythm and chest compression depth were predictors of short term survival (ROSC to ED).

Conclusions

Even limited CPR-feedback combined with training and ongoing debriefing leads to high chest compression quality. Bystander CPR, location, rhythm and chest compression depth are determinants of survival from out of hospital cardiac arrest. Addition of voice prompts does neither modify CPR quality nor outcome in OHCA. CC depth significantly influences survival and therefore more focus should be put on correct delivery. Further studies are needed to examine the best configuration of feedback to improve CPR quality and survival.

Registration

ClinicalTrials.gov (NCT00449969), http://www.clinicalTrials.gov.     

Vasopressin for cardiac arrest: meta-analysis of randomized controlled trials

Background

Prior meta-analyses-reported results of randomised controlled trials (RCTs) published between 1997 and 2004 failed to show any vasopressin-related benefit in cardiac arrest. Based on new RCT-data and a hypothesis of a potentially increased vasoconstricting efficacy of vasopressin, we sought to determine whether the cumulative, current evidence supports or refutes an overall and/or selective benefit for vasopressin regarding sustained restoration of spontaneous circulation (ROSC), long-term survival, and neurological outcome.

Methods

Two reviewers independently searched PubMed, EMBASE, and Cochrane Database for RCTs assigning adults with cardiac arrest to treatment with a vasopressin-containing regimen (vasopressin-group) vs adrenaline (epinephrine) alone (control-group) and reporting on long-term outcomes. Data from 4475 patients in 6 high-methodological quality RCTs were analyzed. Subgroup analyses were conducted according to initial cardiac rhythm and time from collapse to drug administration (T_DRUG) < 20 min.

Results

Vasopressin vs. control did not improve overall rates of sustained ROSC, long-term survival, or favourable neurological outcome. However, in asystole, vasopressin vs. control was associated with higher long-term survival {odds ratio (OR) = 1.80, 95% confidence interval (CI) = 1.04-3.12, P = 0.04}. In asystolic patients of RCTs with average T_DRUG < 20 min, vasopressin vs. control increased the rates of sustained ROSC (data available from 2 RCTs; OR = 1.70, 95% CI = 1.17-2.47, P = 0.005) and long-term survival (data available from 3 RCTs; OR = 2.84, 95% CI = 1.19-6.79, P = 0.02).

Conclusions

Vasopressin use in the resuscitation of cardiac arrest patients is not associated with any overall benefit or harm. However, vasopressin may improve the long-term survival of asystolic patients, especially when average T_DRUG is <20 min.     

Survival from out-of-hospital cardiac arrest in New Zealand following the 2005 resuscitation guideline changes

Aims

The effect of cardiopulmonary resuscitation guideline changes on out-of-hospital survival rates and defibrillation efficacy was investigated. The guideline changes were those recommended by the International Liaison Committee on Resuscitation in 2005.

Methods

A retrospective comparative study was undertaken of out-of-hospital cardiac arrests in the Wellington region. The effect of guideline changes between the periods of 1st July 2005-30th June 2006 and 1st June 2007-31st May 2008 was examined. Data was collected from Wellington Free Ambulance and hospital records in accordance with the Utstein template. The primary outcome measure was survival to hospital discharge. Additional end points included individual shock success, return of spontaneous circulation (ROSC) and survival to hospital admission.

Results

There was no significant increase in survival to hospital discharge with 11% (18/162) pre-change and 12% (20/170) post-change (p = 0.5). First-shock efficacy decreased from 68% (65/96) to 62% (57/92) (p = 0.75). Second shock efficacy decreased from 47% (14/30) to 27% (9/33) (p = 0.12). The proportion of patients with ROSC increased from 34% (55/162) to 42% (72/170) (p = 0.07, Chi squared). The proportion surviving to hospital increased significantly from 22% (36/162) to 36% (61/170) (p = 0.006). Withdrawal of atropine in 2005 had no adverse effect on the outcome.

Conclusion

This study suggests that in the Wellington Region of New Zealand, the new guidelines have improved survival to hospital but not to discharge. Whilst the guideline changes have resulted in a trend towards decreased shock success rates, ROSC and survival to hospital admission have both increased.     

Association between deprivation status at community level and outcomes from out-of-hospital cardiac arrest: a nationwide observational study

Study objectives

We sought to examine the association between area deprivation and outcomes of out-of-hospital cardiac arrest in Korea.

Methods

Data were obtained from the emergency medical service (EMS) system. A nationwide OHCA cohort database from January2006 to December 2007 was constructed via hospital chart review and ambulance run sheet data. We enrolled all EMS-assessed OHCA victims and excluded cases without available hospital outcome data or residential address. The Carstairs index was used to categorize districts according to level of deprivation into five quintiles, from (Q1, the least deprived) to (Q5, the most deprived). Main outcomes were survival to hospital discharge, survival to admission, and return of spontaneous circulation (ROSC).

Results

34,227 patients were included. Initial rhythm, witnessed status, attempted bystander cardiopulmonary resuscitation (CPR), CPR by EMS, CPR in the emergency department (ED), and elapsed time interval significantly varied according to area deprivation level (p < 0.001). OHCA outcomes were consistently worse in the most deprived areas. The adjusted OR (95% CI) for survival to hospital discharge was 0.58 (0.45-0.77) in the most deprived areas compared to the least deprived areas.

Conclusion

Community deprivation was strongly associated with survival among out-of-hospital cardiac arrest patients in Korea.     

Impact of transport to critical care medical centers on outcomes after out-of-hospital cardiac arrest

Background

Post-resuscitation care has emerged as an important predictor of survival from out-of-hospital cardiac arrest (OHCA). In Japan, selected hospitals are certified as Critical Care Medical Centers (CCMCs) based on their ability and expertise.

Hypothesis

Outcome after OHCA is better in patients transported to a CCMC compared a non-critical care hospital (NCCH).

Materials and methods

Adults with OHCA of presumed cardiac etiology, treated by emergency medical services systems, and transported in Osaka from January 1, 2005 to December 31, 2007 were registered using a prospective Utstein style population cohort database. Primary outcome measure was 1 month neurologically favorable survival (CPC ≤ 2). Outcomes of patients transported to CCMC were compared with patients transported to NCCH using multiple logistic regressions and stratified on the basis of stratified field ROSC.

Results

10,383 cases were transported. Of these, 2881 were transported to CCMC and 7502 to NCCH. Neurologically favorable 1-month survival was greater in the CCMC group [6.7% versus 2.8%, P < 0.001]. Among patients who were transported to hospital without field ROSC, neurologically favorable outcome was greater in the CCMC group than the NCCH group [1.7% versus 0.5%; adjusted odds ratio (OR), 3.39; 95% confidence interval (CI), 2.17-5.29; P < 0.001]. In the presence of field ROSC, survival was similar between the groups [43% versus 41%; adjusted OR, 1.09; 95% CI, 0.82-1.45; P = 0.554].

Conclusions

Survival after OHCA of presumed cardiac etiology transported to CCMCs was better than those transported to NCCHs. For OHCA patients without field ROSC, transport to a CCMC was an independent predictor for a good neurological outcome.     

Treatment of monitored out-of-hospital ventricular fibrillation and pulseless ventricular tachycardia utilising the precordial thump

Background

Few studies have described the value of the precordial thump (PT) as first-line treatment of monitored out-of-hospital cardiac arrest (OHCA) from ventricular fibrillation and pulseless ventricular tachycardia (VF/VT).

Methods

Patient data was extracted from the Victorian Ambulance Cardiac Arrest Registry (VACAR) for all OHCA witnessed by paramedics between 2003 and 2011. Adult patients who suffered a monitored VF/VT of presumed cardiac aetiology were included. Cases were excluded if the arrest occurred after arrival at hospital, or a ‘do not resuscitate’ directive was documented. Patients were assigned into two groups according to the use of the PT or defibrillation as first-line treatment. The study outcomes were: impact of first shock/thump on return of spontaneous circulation (ROSC), overall ROSC, and survival to hospital discharge.

Results

A total of 434 cases met the eligibility criteria, of which first-line treatment involved a PT in 103 (23.7%) and immediate defibrillation in 325 (74.8%) cases. Patient characteristics did not differ significantly between groups. Seventeen patients (16.5%) observed a PT-induced rhythm change, including five cases of ROSC and 10 rhythm deteriorations. Immediate defibrillation resulted in significantly higher levels of immediate ROSC (57.8% vs. 4.9%, p < 0.0001), without excess rhythm deteriorations (12.3% vs. 9.7%, p = 0.48). Of the five successful PT attempts, three required defibrillation following re-arrest. Overall ROSC and survival to hospital discharge did not differ significantly between groups.

Conclusion

The PT used as first-line treatment of monitored VF/VT rarely results in ROSC, and is more often associated with rhythm deterioration.     

Early coronary revascularization improves 24 h survival and neurological function after ischemic cardiac arrest. A randomized animal study

Background

Survival after out-of-hospital cardiac arrest (OHCA) remains poor. Acute coronary obstruction is a major cause of OHCA. We hypothesize that early coronary reperfusion will improve 24 h-survival and neurological outcomes.

Methods

Total occlusion of the mid LAD was induced by balloon inflation in 27 pigs. After 5 min, VF was induced and left untreated for 8 min. If return of spontaneous circulation (ROSC) was achieved within 15 min (21/27 animals) of cardiopulmonary resuscitation (CPR), animals were randomized to a total of either 45 min (group A) or 4 h (group B) of LAD occlusion. Animals without ROSC after 15 min of CPR were classified as refractory VF (group C). In those pigs, CPR was continued up to 45 min of total LAD occlusion at which point reperfusion was achieved. CPR was continued until ROSC or another 10 min of CPR had been performed. Primary endpoints for groups A and B were 24-h survival and cerebral performance category (CPC). Primary endpoint for group C was ROSC before or after reperfusion.

Results

Early compared to late reperfusion improved survival (10/11 versus 4/10, p = 0.02), mean CPC (1.4 ± 0.7 versus 2.5 ± 0.6, p = 0.017), LVEF (43 ± 13 versus 32 ± 9%, p = 0.01), troponin I (37 ± 28 versus 99 ± 12, p = 0.005) and CK-MB (11 ± 4 versus 20.1 ± 5, p = 0.031) at 24-h after ROSC. ROSC was achieved in 4/6 animals only after reperfusion in group C.

Conclusions

Early reperfusion after ischemic cardiac arrest improved 24 h survival rate and neurological function. In animals with refractory VF, reperfusion was necessary to achieve ROSC.     

Out-of-hospital cardiac arrest frequency and survival: Evidence for temporal variability

Aim

Some cardiac phenomena demonstrate temporal variability. We evaluated temporal variability in out-of-hospital cardiac arrest (OHCA) frequency and outcome.

Methods

Prospective cohort study (the Resuscitation Outcomes Consortium) of all OHCA of presumed cardiac cause who were treated by emergency medical services within 9 US and Canadian sites between 12/1/2005 and 02/28/2007. In each site, Emergency Medical System records were collected and analyzed. Outcomes were individually verified by trained data abstractors.

Results

There were 9667 included patients. Median age was 68 (IQR 24) years, 66.7% were male and 8.3% survived to hospital discharge. The frequency of cardiac arrest varied significantly across time blocks (p < 0.001). Compared to the 0001-0600 hourly time block, the odds ratios and 95% CIs for the occurrence of OHCA were 2.02 (1.90, 2.15) in the 0601-1200 block, 2.01 (1.89, 2.15) in the 1201-1800 block, and 1.73 (1.62, 1.85) in the 1801-2400 block. The frequency of all OHCA varied significantly by day of week (p = 0.03) and month of year (p < 0.001) with the highest frequencies on Saturday and during December. Survival to hospital discharge was lowest when the OHCA occurred during the 0001-0600 time block (7.3%) and highest during the 1201-1800 time block (9.6%). Survival was highest for OHCAs occurring on Mondays (10.0%) and lowest for those on Wednesdays (6.8%) (p = 0.02).

Conclusion

There is temporal variability in OHCA frequency and outcome. Underlying patient, EMS system and environmental factors need to be explored to offer further insight into these observed patterns.     

Myocardial infarction is a frequent cause of exercise-related resuscitated out-of-hospital cardiac arrest in a general non-athletic population

Background

Performing exercise is shown to prevent cardiovascular disease, but the risk of an out-of-hospital cardiac arrest (OHCA) is temporarily increased during strenuous activity. We examined the etiology and outcome after successfully resuscitated OHCA during exercise in a general non-athletic population.

Methods

Consecutive patients with OHCA were admitted with return of spontaneous circulation (ROSC) or on-going resuscitation at hospital arrival (2002–2011). Patient charts were reviewed for post-resuscitation data. Exercise was defined as moderate/vigorous physical activity.

Results

A total of 1393 OHCA-patients were included with 91(7%) arrests occurring during exercise. Exercise-related OHCA-patients were younger (60 ± 13 vs. 65 ± 15, p < 0.001) and predominantly male (96% vs. 69%, p < 0.001). The arrest was more frequently witnessed (94% vs. 86%, p = 0.02), bystander CPR was more often performed (88% vs. 54%, p < 0.001), time to ROSC was shorter (12 min (IQR: 5–19) vs. 15 (9–22), p = 0.007) and the primary rhythm was more frequently shock-able (91% vs. 49%, p < 0.001) compared to non-exercise patients. Cardiac etiology was the predominant cause of OHCA in both exercise and non-exercise patients (97% vs. 80%, p < 0.001) and acute coronary syndrome was more frequent among exercise patients (59% vs. 38%, p < 0.001). One-year mortality was 25% vs. 65% (p < 0.001), and exercise was even after adjustment associated with a significantly lower mortality (HR = 0.40 (95%CI: 0.23–0.72), p = 0.002).

Conclusions

OHCA occurring during exercise was associated with a significantly lower mortality in successfully resuscitated patients even after adjusting for confounding factors. Acute coronary syndrome was more common among exercise-related cardiac arrest patients.