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.     

Improved outcome of extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest – A comparison with that for extracorporeal rescue for in-hospital cardiac arrest

Purpose

The aim was to investigate the effects of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA) and compare the results with those of in-hospital cardiac arrest (IHCA).

Methods

We analyzed our extracorporeal membrane oxygenation (ECMO) results for patients who received ECPR for OHCA or IHCA in the last 5 years. Pre-arrest, resuscitation, and post-resuscitative data were evaluated.

Results

In the last 5 years, ECPR was used 230 times for OHCA (n = 31) and IHCA (n = 199). The basic demographic data showed significant differences in age, cardiomyopathy, and location of the initial CPR. Duration of ischemia was shorter in the IHCA group (44.4 ± 24.7 min vs. 67.5 ± 30.6 min, p < 0.05). About 50% of each group underwent a further intervention to treat the underlying etiology. ECMO was maintained for a shorter duration in the OHCA patients (61 ± 48 h vs. 94 ± 122 h, p < 0.05). Survival to discharge was similar in the two groups (38.7% for OHCA vs. 31.2% for IHCA, p > 0.05), as was the favorable outcome rate (25.5% for OHCA vs. 25.1% for IHCA, p > 0.05). Survival was acceptable (about 33%) in both groups when the duration of ischemia was no longer than 75 min.

Conclusions

In addition to having a beneficial effect in IHCA, ECPR can lead to survival and a positive neurological outcome in selected OHCA patients after prolonged resuscitation. Our results suggest that further investigation of the use of ECMO in OHCA is warranted.     

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.     

A 5-year experience with cardiopulmonary resuscitation using extracorporeal life support in non-postcardiotomy patients with cardiac arrest

Background

Cardiopulmonary resuscitation (CPR) using extracorporeal life support (ECLS) system has been successfully used to support patients with in- and out-of-hospital cardiac arrest (IHCA, OHCA) when conventional measures have failed. The purpose of the current study is to report on our experience with extracorporeal CPR in non-postcardiotomy patients.

Methods

We retrospectively analysed a total of 85 consecutive adult patients, who have been treated with ECLS between January 2007 and January 2012.

Results

The mean CPR duration was 40 min (20–70 min). The mean ECLS support duration was 49 h (12–92 h). Twenty-eight patients (33%) had ECLS related complications. Forty patients (47%) were successfully weaned and 29 patients (34%) survived to hospital discharge. Among survivors, 93% were without severe neurologic deficit. Duration of CPR was shorter for survivors than for non-survivors [(25: 20–50 min) vs. (50: 25–86 min); p = 0.003]. Immediately after ECLS start, the mean blood lactate level was lower (p = 0.003), and the mean pH value was higher in the survivors’ group (p < 0.0001) compared to the non-survivors’ group. The CPR duration for the IHCA group (25: 20–50 min) was shorter compared to the OHCA group (70: 55–110 min; p < 0.0001). The survival rate in this group was higher compared to the OHCA group (42% vs. 15%; p < 0.02).

Conclusions

CPR using modern miniaturized ECLS systems should be established in the treatment of prolonged cardiac arrest and unsuccessful conventional CPR in selected patients. CPR with ECLS for OHCA has worse outcomes compared to IHCA. Duration of CPR was independent risk factor for mortality after extracorporeal CPR.     

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.     

The benefits of a simplified method for CPR training of medical professionals: A randomized controlled study

Objectives

We developed and tested a training method for basic life support incorporating defibrillator feedback during simulated cardiac arrest (CA) to determine the impact on the quality and retention of CPR skills.

Methods

298 subjects were randomized into 3 groups. All groups received a 2 h training session followed by a simulated CA test scenario, immediately after training and at 3 months. Controls used a non-feedback defibrillator during training and testing. Group 1 was trained and tested with an audiovisual feedback defibrillator. During training, Group 1 reviewed quantitative CPR data from the defibrillator. Group 2 was trained as per Group 1, but was tested using the non-feedback defibrillator. The primary outcome was difference in compression depth between groups at initial testing. Secondary outcomes included differences in rate, depth at retesting, compression fraction, and self-assessment.

Results

Groups 1 and 2 had significantly deeper compressions than the controls (35.3 ± 7.6 mm, 43.7 ± 5.8 mm, 42.2 ± 6.6 mm for controls, Groups 1 and 2, P = 0.001 for Group 1 vs. controls; P = 0.001 for Group 2 vs. controls). At three months, CPR depth was maintained in all groups but remained significantly higher in Group 1 (39.1 ± 9.9 mm, 47.0 ± 7.4 mm, 42.2 ± 8.4 mm for controls, Groups 1 and 2, P = 0.001 for Group 1 vs. control). No significant differences were noted between groups in compression rate or fraction.

Conclusions

A simplified 2 h training method using audiovisual feedback combined with quantitative review of CPR performance improved CPR quality and retention of these skills.     

A Simple Audio-visual Prompt Device Can Improve CPR Performance

Background

An adjunct to assist cardiopulmonary resuscitation (CPR) might improve the quality of CPR performance.

Study Objectives

This study was conducted to evaluate whether a simple audio-visual prompt device improves CPR performance by emergency medical technicians (EMTs).

Methods

From June 2008 to October 2008, 55 EMTs (39 men, mean age 34.9 ± 4.8 years) participated in this study. A simple audio-visual prompt device was developed. The device generates continuous metronomic sounds for chest compression at a rate of 100 beats/min with a distinct 30^th sound followed by two respiration sounds, each for 1 second. All EMTs were asked to perform a 2-min CPR series on a manikin without the device, and one 2-min CPR series with the device.

Results

The average rate of chest compressions was more accurate when the device was used than when the device was not used (101.4 ± 12.7 vs. 109.0 ± 17.4/min, respectively, p = 0.012; 95% confidence interval [CI] 97.2–103.8 vs. 104.5–113.5/min, respectively), and hands-off time during CPR was shorter when the device was used than when the device was not used (5.4 ± 0.9 vs. 9.2 ± 3.9 s, respectively, p < 0.001; 95% CI 5.2–5.7 vs. 8.3–10.3 s, respectively). The mean tidal volume during CPR with the device was lower than without the device, resulting in the prevention of hyperventilation (477.6 ± 60.0 vs. 636.6 ± 153.4 mL, respectively, p < 0.001; 95% CI 463.5–496.2 vs. 607.3–688.9 mL, respectively).

Conclusion

A simple audio-visual prompt device can improve CPR performance by emergency medical technicians.     

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.     

Chest compressions performed by ED staff: a randomized cross-over simulation study on the floor and on a stretcher

Background

Multiple factors may contribute to the observed survival variability following in-hospital cardiopulmonary resuscitation (CPR). While in-hospital CPR is most often performed on patients lying on a bed or stretcher, CPR training uses primarily manikins placed on the floor. We analyzed the quality of external chest compressions (ECC) in simulated cardiac arrest scenarios occurring both on a stretcher and on the floor.

Methods

Prospective cross-over simulation study enrolling ED nurses and nurse's aides as part of an annual evaluation. Simulated CPR was performed in the 2 rescuer-mode for 2 min, both kneeling on the floor, and standing beside a knee high stretcher. The order of position was randomized. ECC parameters were compared.

Results

ED nurses (n = 48) and nurse's aides (n = 26) performed 128 scenarios. Mean ECC depth was 32 ± 13 mm on the floor and 27 ± 11 mm on a stretcher (?: 5 mm, 95%CI [3-7], P < .001). Participants last trained within a year (n = 17) developed deeper ECCs than their colleagues (n = 47) in both positions (floor: 39 ± 12 mm vs stretcher: 34 ± 11 mm (p = 0.016) for those trained within the year, and floor: 29 ± 12 mm vs stretcher: 24 ± 10 mm (P < .001) for those trained over a year ago).

Conclusions

The quality of chest compressions performed by ED staff was below 2005 guideline standards, with decreased ECC depth during CPR on a stretcher. Annual refresher courses should be implemented in the ED, with a focus on obtaining required ECC depth while standing next to a stretcher.     

Compressions during defibrillator charging shortens shock pause duration and improves chest compression fraction during shockable out of hospital cardiac arrest

Background

Previous studies have demonstrated significant relationships between shock pause duration and survival to hospital discharge from shockable out-of hospital (OHCA) cardiac arrest. Compressions during defibrillator charging (CDC) has been proposed as a technique to shorten shock pause duration.

Objective

We sought to determine the impact of CDC on shock pause duration and CPR quality measures in shockable OHCA.

Methods

We performed a retrospective review of all treated adult OHCA occurring over a 1 year period beginning August 1, 2011 after training EMS agencies in CDC. We included OHCA patients with an initial shockable rhythm, available CPR process data and shock pause data for up to the first three shocks of the resuscitation. CDC by EMS personnel was confirmed by review of impedance channel measures. We evaluated the relationship between CDC and shock pause duration as the primary outcome measure. Secondary outcome measures investigated the association between CDC and CPR quality measures.

Results

Among 747 treated OHCA 149 (23.4%) presented in a shockable rhythm of which 129 (81.6%) met study inclusion criteria. Seventy (54.2%) received CDC. There was no significant difference between the CDC and no CDC group with respect to Utstein variables. Median pre-shock pause (15.0 vs. 3.5 s; Δ 11.5; 95% CI: 6.81, 16.19), post-shock pause (4.0 vs. 3.0 s; Δ 1.0; 95% CI: −2.57, 4.57), and peri-shock pause (21.0 vs. 9.0 s; Δ 12.0; 95% CI: 5.03, 18.97) were all lower for those who received CDC. Mean chest compression fraction was significantly greater (0.77 vs. 0.70, Δ 0.07; 95% CI: 0.03, 0.11) with CDC. No significant difference was noted in compression rate or depth with CDC. Clinical outcomes did not differ between the two approaches (return of spontaneous circulation 62.7% vs. 62.9% p = 0.98, survival 25.4% vs. 27.1% p = 0.82), although the study was not powered to detect clinical outcome differences.

Conclusions

Compressions during defibrillator charging may shorten shock pause duration and improves chest compression fraction in shockable OHCA. Given the impact on shock pause duration, further study with a larger sample size is required to determine the impact of this technique on clinical outcomes from shockable OHCA.     

CPR variability during ground ambulance transport of patients in cardiac arrest

Aim of study

High-quality CPR is associated with improved outcomes from out-of-hospital cardiac arrest (OHCA). The purpose of this investigation was to compare the quality of CPR provided at the prehospital scene, during ambulance transport, and during the early minutes in the emergency department (ED).

Methods

A prospective observational review of consecutive adult patients with non-traumatic OHCA was conducted between September 2008 and February 2010. Patients with initiation of prehospital CPR were included as part of a statewide cardiac resuscitation quality improvement program. A monitor-defibrillator with accelerometer-based CPR measurement capability (E-series, ZOLL Medical) was utilized. CPR quality measures included variability in chest compression (CC) depth and rate, mean depth and rate, and the CC fraction. Variability of CC was defined as the mean of minute-to-minute standard deviation in CC depth or rate. CC fraction was defined as the percent of time that CPR was being performed when appropriate throughout resuscitation.

Results

Fifty-seven adult patients with OHCA had electronic CPR data recorded at the scene, in the ambulance, and upon arrival in the ED. Across time periods, there was increased variability in CC depth (scene: 0.20 in.; transport: 0.26 in.; ED: 0.31 in., P < 0.01) and rate (scene: 18.2 CC min⁻¹; transport: 26.1 CC min⁻¹; ED: 26.3 CC min⁻¹, P < 0.01). The mean CC depth, rate, and the CC fraction did not differ significantly between groups.

Conclusions

There was increased CC variability from the prehospital scene to the ED though there was no difference in mean CC depth, rate, or in CC fraction. The clinical significance of CC variability remains to be determined.     

The impact of therapeutic hypothermia on neurological function and quality of life after cardiac arrest

Aims

To assess the impact of therapeutic hypothermia on cognitive function and quality of life in comatose survivors of out of Hospital Cardiac arrest (OHCA).

Methods

We prospectively studied comatose survivors of OHCA consecutively admitted in a 4-year period. Therapeutic hypothermia was implemented in the last 2-year period, intervention period (n = 79), and this group was compared to patients admitted the 2 previous years, control period (n = 77). We assessed Cerebral Performance Category (CPC), survival, Mini Mental State Examination (MMSE) and self-rated quality of life (SF-36) 6 months after OHCA in the subgroup with VF/VT as initial rhythm.

Results

CPC in patients alive at hospital discharge was significantly better in the intervention period with a CPC of 1–2 in 97% vs. 71% in the control period, p = 0.003, corresponding to an adjusted odds ratio of a favourable cerebral outcome of 17, p = 0.01. No significant differences were found in long-term survival (57% vs. 56% alive at 30 months), MMSE, or SF-36. Therapeutic hypothermia (hazard ratio: 0.15, p = 0.007) and bystander CPR (hazard ratio 0.19, p = 0.002) were significantly related to survival in the intervention period.

Conclusion

CPC at discharge from hospital was significantly improved following implementation of therapeutic hypothermia in comatose patients resuscitated from OCHA with VF/VT. However, significant improvement in survival, cognitive status or quality of life could not be detected at long-term follow-up.     

Comparison of Medical Priority Dispatch (MPD) and Criteria Based Dispatch (CBD) relating to cardiac arrest calls

Background

Prompt emergency medical service (EMS) system activation with rapid delivery of pre-hospital treatment is essential for patients suffering out-of-hospital cardiac arrest (OHCA). The two most commonly used dispatch tools are Medical Priority Dispatch (MPD) and Criteria Based Dispatch (CBD). We compared cardiac arrest call processing using these two dispatch tools in two different dispatch centres.

Methods

Observational study of adult EMS confirmed (non-EMS witnessed) OHCA calls during one year in Richmond, USA (MPD) and Oslo, Norway (CBD). Patients receiving CPR prior to call, interrupted calls or calls where the caller did not have access to the patients were excluded from analysis. Dispatch logs, ambulance records and digitalized dispatcher and caller voice recordings were compared.

Results

The MPDS-site processed 182 cardiac arrest calls and the CBD-site 232, of which 100 and 140 calls met the inclusion criteria, respectively. The recognition of cardiac arrest was not different in the MPD and CBD systems; 82% vs. 77% (p = 0.42), and pre-EMS arrival CPR instructions were offered to 81% vs. 74% (p = 0.22) of callers, respectively. Time to ambulance dispatch was median (95% confidence interval) 15 (13, 17) vs. 33 (29, 36) seconds (p < 0.001) and time to chest compression delivery; 4.3 (3.7, 4.9) vs. 3.7 (3.0, 4.1) min for the MPD and CBD systems, respectively (p = 0.05).

Conclusion

Pre-arrival CPR instructions were offered faster and more frequently in the CBD system, but in both systems chest compressions were delayed 3–4 min. Earlier recognition of cardiac arrest and improved CPR instructions may facilitate earlier lay rescuer CPR.     

Haemodynamic variables and functional outcome in hypothermic patients following out-of-hospital cardiac arrest

Aim of the study

To evaluate the association between haemodynamic variables during the first 24 h after intensive care unit (ICU) admission and neurological outcome in out-of-hospital cardiac arrest (OHCA) victims undergoing therapeutic hypothermia.

Methods

In a multi-disciplinary ICU, records were reviewed for comatose OHCA patients undergoing therapeutic hypothermia. The hourly variable time integral of haemodynamic variables during the first 24 h after admission was calculated. Neurologic outcome was assessed at day 28 and graded as favourable or adverse based on the Cerebral Performance Category of 1–2 and 3–5. Bi- and multivariate regression models adjusted for confounding variables were used to evaluate the association between haemodynamic variables and functional outcome.

Results

67/134 patients (50%) were classified as having favourable outcome. Patients with adverse outcome had a higher mean heart rate (73 [62–86] vs. 66 [60–78] bpm; p = 0.04) and received noradrenaline more frequently (n = 17 [25.4%] vs. n = 9 [6%]; p = 0.02) and at a higher dosage (128 [56–1004] vs. 13 [2–162] μg h⁻¹; p = 0.03) than patients with favourable outcome. The mean perfusion pressure (mean arterial blood pressure minus central venous blood pressure) (OR = 1.001, 95% CI  = 1–1.003; p = 0.04) and cardiac index time integral (OR = 1.055, 95% CI = 1.003–1.109; p = 0.04) were independently associated with adverse outcome at day 28.

Conclusion

Mean perfusion pressure and cardiac index during the first 24 h after ICU admission were weakly associated with neurological outcome in an OHCA population undergoing therapeutic hypothermia. Further studies need to elucidate whether norepinephrine-induced increases in perfusion pressure and cardiac index may contribute to adverse neurologic outcome following OHCA.     

Chest compression-only cardiopulmonary resuscitation performed by lay rescuers for adult out-of-hospital cardiac arrest due to non-cardiac aetiologies

Objective

Bystander CPR improves survival in patients with out-of-hospital cardiac arrest (OHCA). For adult sudden collapse, bystander chest compression-only CPR (COCPR) is recommended in some circumstances by the American Heart Association and European Resuscitation Council. However, adults who arrest from non-cardiac causes may also receive COCPR. Because rescue breathing may be more important for individuals suffering OHCA secondary to non-cardiac causes, COCPR is not recommended for these cases. We evaluated the relationship of lay rescuer COCPR and survival after OHCA from non-cardiac causes.

Methods

Analysis of a statewide Utstein-style registry of adult OHCA, during a large scale campaign endorsing COCPR for OHCA from presumed cardiac cause. The relationship between lay rescuer CPR (both conventional CPR and COCPR) and survival to hospital discharge was evaluated.

Results

Presumed non-cardiac aetiologies of OHCA accounted for 15% of all cases, and lay rescuer CPR was provided in 29% of these cases. Survival to hospital discharge occurred in 3.8% after conventional CPR, 2.7% after COCPR, and 4.0% after no CPR (p = 0.85). The proportion of patients receiving COCPR was much lower in the cohort of OHCA from respiratory causes (8.3%) than for those with presumed cardiac OHCA (18.0%; p < 0.001).

Conclusions

In the setting of a campaign endorsing lay rescuer COCPR for cardiac OHCA, bystanders were less likely to perform COCPR on OHCA victims who might benefit from rescue breathing.     

Reduced in-hospital survival rates of out-of-hospital cardiac arrest victims with obstructive pulmonary disease

Aim

Out-of-hospital cardiac arrest (OHCA) due to sustained ventricular tachycardia/fibrillation (VT/VF) is common and often lethal. Patient's co-morbidities may determine survival after OHCA, and be instrumental in post-resuscitation care, but are poorly studied. We aimed to study whether patients with obstructive pulmonary disease (OPD) have a lower survival rate after OHCA than non-OPD patients.

Methods

We performed a community-based cohort study of 1172 patients with non-traumatic OHCA with ECG-documented VT/VF between 2005 and 2008. We compared survival to Emergency Room (ER), to hospital admission, to hospital discharge, and at 30 days after OHCA, of OPD-patients and non-OPD patients, using logistic regression analysis. We also compared 30-day survival of patients who were admitted to hospital, using multivariate logistic regression analysis.

Results

OPD patients (n = 178) and non-OPD patients (n = 994) had comparable survival to ER (75% vs. 78%, OR 0.9 [95% CI: 0.6–1.3]) and to hospital admission (56% vs. 57%, OR 1.0 [0.7–1.4]). However, survival to hospital discharge was significantly lower among OPD patients (21% vs. 33%, OR 0.6 [0.4–0.9]). Multivariate regression analysis among patients who were admitted to hospital (OPD: n = 100, no OPD: n = 561) revealed that OPD was an independent determinant of reduced 30-day survival rate (39% vs. 59%, adjusted OR 0.6 [0.4–1.0, p = 0.035]).

Conclusion

OPD-patients had lower survival rates after OHCA than non-OPD patients. Survival to ER and to hospital admission was not different between both groups. However, among OHCA victims who survived to hospital admission, OPD was an independent determinant of reduced 30-day survival rate.     

Can a flowchart improve the quality of bystander cardiopulmonary resuscitation?

Background

Since the introduction of basic life support in the 1950s, on-going efforts have been made to improve the quality of bystander cardiopulmonary resuscitation (CPR). Even though bystander-CPR can increase the chance of survival almost fourfold, the rates of bystander initiated CPR have remained low and rarely exceed 20%. Lack of confidence and fear of committing mistakes are reasons why helpers refrain from initiating CPR. The authors tested the hypothesis that quality and confidence of bystander-CPR can be increased by supplying lay helpers with a basic life support flowchart when commencing CPR, in a simulated resuscitation model.

Materials and methods

After giving written informed consent, 83 medically untrained laypersons were randomised to perform basic life support for 300s with or without a supportive flowchart. The primary outcome parameter was hands-off time (HOT). Furthermore, the participants’ confidence in their actions on a 10-point Likert-like scale and time-to-chest compressions were assessed.

Results

Overall HOT was 147 ± 30 s (flowchart) vs. 169 ± 55 s (non-flowchart), p = 0.024. Time to chest compressions was significantly longer in the flowchart group (60 ± 24 s vs. 23 ± 18 s, p < 0.0001). Participants in the flowchart group were significantly more confident when performing BLS than the non-flowchart counterparts (7 ± 2 vs. 5 ± 2, p = 0.0009).

Conclusions

A chart provided at the beginning of resuscitation attempts improves quality of CPR significantly by decreasing HOT and increasing the participants’ confidence when performing CPR. As reducing HOT is associated with improved outcome and positively impacting the helpers’ confidence is one of the main obstacles to initiate CPR for lay helpers, charts could be utilised as simple measure to improve outcome in cardiopulmonary arrest.     

Use of impedance threshold device in conjunction with our novel adhesive glove device for ACD-CPR does not result in additional chest decompression

Objective

To evaluate the hemodynamic effects of using an adhesive glove device (AGD) to perform active compression–decompression CPR (AGD-CPR) in conjunction with an impedance threshold device (ITD) in a pediatric cardiac arrest model.

Design

Controlled, randomized animal study.

Methods

In this study, 18 piglets were anesthetized, ventilated, and continuously monitored. After 3 min of untreated ventricular fibrillation, animals were randomized (6/group) to receive either standard CPR (S-CPR), active compression–decompression CPR via adhesive glove device (AGD-CPR) or AGD-CPR along with an ITD (AGD-CPR + ITD) for 2 min at 100–120 compressions/min. AGD is delivered using a fingerless leather glove with a Velcro patch on the palmer aspect and the counter Velcro patch adhered to the pig's chest. Data (mean ± SD) were analyzed using one-way ANOVA with pair wise multiple comparisons to assess differences between groups. p-Value ≤ 0.05 was considered significant.

Results

Both AGD-CPR and AGD-CPR + ITD groups produced lower intrathoracic pressure (IttP, mmHg) during decompression phase (−13.4 ± 6.7, p = 0.01 and −11.9 ± 6.5, p = 0.01, respectively) in comparison to S-CPR (−0.3 ± 4.2). Carotid blood flow (CBF, % of baseline mL/min) was higher in AGD-CPR and AGD-CPR + ITD (respectively 64.3 ± 47.3%, p = 0.03 and 67.5 ± 33.1%, p = 0.04) as compared with S-CPR (29.1 ± 12.5%). Coronary perfusion pressure (CPP, mmHg) was higher in AGD-CPR and AGD-CPR + ITD (respectively 19.7 ± 4.6, p = 0.04 and 25.6 ± 12.1, p = 0.02) when compared to S-CPR (9.6 ± 9.1). There was no statistically significant difference between AGD-CPR and AGD-CPR + ITD groups with reference to intra-thoracic pressure, carotid blood flow and coronary perfusion pressure.

Conclusion

Active compression decompression delivered by this simple and inexpensive adhesive glove device resulted in improved cerebral blood flow and coronary perfusion pressure. There was no statistically significant added effect of ITD use along with AGD-CPR on the decompression of the chest.     

Comparing three CPR feedback devices and standard BLS in a single rescuer scenario: A randomised simulation study

Background

Efficiently performed basic life support (BLS) after cardiac arrest is proven to be effective. However, cardiopulmonary resuscitation (CPR) is strenuous and rescuers’ performance declines rapidly over time. Audio-visual feedback devices reporting CPR quality may prevent this decline. We aimed to investigate the effect of various CPR feedback devices on CPR quality.

Methods

In this open, prospective, randomised, controlled trial we compared three CPR feedback devices (PocketCPR^®, CPRmeter^®, iPhone app PocketCPR^®) with standard BLS without feedback in a simulated scenario. 240 trained medical students performed single rescuer BLS on a manikin for 8 min. Effective compression (compressions with correct depth, pressure point and sufficient decompression) as well as compression rate, flow time fraction and ventilation parameters were compared between the four groups.

Results

Study participants using the PocketCPR^® performed 17 ± 19% effective compressions compared to 32 ± 28% with CPRmeter^®, 25 ± 27% with the iPhone app PocketCPR^®, and 35 ± 30% applying standard BLS (PocketCPR^® vs. CPRmeter^®p = 0.007, PocketCPR^® vs. standard BLS p = 0.001, others: ns). PocketCPR^® and CPRmeter^® prevented a decline in effective compression over time, but overall performance in the PocketCPR^® group was considerably inferior to standard BLS. Compression depth and rate were within the range recommended in the guidelines in all groups.

Conclusion

While we found differences between the investigated CPR feedback devices, overall BLS quality was suboptimal in all groups. Surprisingly, effective compression was not improved by any CPR feedback device compared to standard BLS. All feedback devices caused substantial delay in starting CPR, which may worsen outcome.