A manually powered mechanical resuscitation device used by a single rescuer: A randomised controlled manikin study

Survival to intensive care unit discharge among in-hospital cardiac arrest patients by applying audiovisual feedback device

Aims

Survival rates after in‐hospital cardiac arrest remain very low. Although there is evidence that the use of audiovisual feedback devices can improve compression components, there are no data on patient survival. Therefore, we conducted this study to analyse the survival rate of patients with in‐hospital cardiac arrest after discharge from the intensive care unit.

Methods and results

This study was a secondary analysis of a prospective, randomized, controlled, parallel study of patients who received either standard manual chest compression or a real‐time feedback device. Parametric and semi‐parametric models were fitted to the data. Different survival time of length of stay was investigated by univariate and multiple analyses. Pearson's correlation between length of stay and hospital length of stay was obtained. A total of 900 patients with a mean survival time of 35 days were included. Intervention was associated with a higher length of stay. Relative time was significant in adjusted fitted log‐normal regression for intervention group, female gender, and cardiopulmonary resuscitation in the night shift. A positive correlation between length of stay and hospital length of stay was found.

Conclusions

Implementation of feedback device improved survival and length of stay. Cardiopulmonary resuscitation performance during the night shift decreased the survival time, which could be due to the inexperienced staff available outside working hours.

Devices to enhance organ perfusion during cardiopulmonary resuscitation

INTRODUCTION

The recommended method of cardiopulmonary resuscitation (CPR) has been closed-chest cardiac compressions, but the development of CPR adjunctive devices has called into question the efficacy and role of these adjunctive devices. In this review, we provide a comprehensive evaluation and discussion on the commercially available noninvasive CPR adjuncts used during out-of-hospital cardiac arrest (OHCA).

AREAS COVERED

We review the three most common CPR adjunctive devices: the piston mechanism, the load distributing band, and the impedance threshold device. All three CPR adjunctive devices have preclinical data to support their use during cardiac arrest. In clinical trials, limited data show improvement in survival and neurologic recovery for these devices, and there is insufficient high-level evidence to support their use over manual chest compressions. However, there is a role for them when adequate manual chest compressions are not feasible.

EXPERT OPINION

The commercially available CPR adjuncts do not consistently show improved outcomes in the literature. There is still a need for research and development into innovative solutions to improve OHCA survival and neurologic recovery. Efforts focused on increasing the speed of CPR initiation and increasing perfusion to the cerebral and coronary vasculature have the potential to advance resuscitative practices.

Effects of the Cardio First AngelTM on chest compression performance

BACKGROUND

Survival rates of out-of-hospital cardiac arrest remain poor. Bystander cardiopulmonary resuscitation (CPR) is crucial for survival and feedback devices could improve its quality.

OBJECTIVE

We investigated the quality of chest compression when using the Cardio First AngelTM (CFA) feedback device compared to standard basic life support (BLS). The analysis focused on laymen.

METHODS

Laymen without (n= 43) and with (n= 96) explanation of the device, medical students (n= 128) and medical staff (n= 27) performed 60 seconds of standard versus assisted chest compression using the CFA on a resuscitation manikin. Compression frequency, depth and position were analyzed according to current guidelines.

RESULTS

Laymen showed significantly better success rates regarding correct compression depth when using the CFA (23.3% vs. 55.8%, p= 0.004 and 25.0% vs. 52.1%, p< 0.001, laymen without and with explanation of the device, respectively). Medical students likewise improved (22.7% vs. 42.2%, p= 0.004). Hand positioning was 100% correct in all groups with the device. Improvement in frequency yielded by the CFA was more pronounced for probands with fears of contact (p= 0.02). The benefit of using the device did not differ significantly in laymen with or without explanation.

CONCLUSIONS

Chest compression as performed by laymen was significantly improved with regard to compression depth when using the CFA for guidance and feedback. With the device, no cases of incorrect hand positioning occurred in any group.

Is a mechanical-assist device better than manual chest compression? A randomized controlled trial

Background

Chest compression quality is a determinant of survival from sudden cardiac arrest. The CPR RsQ Assist Device (CPR RAD) is a new cardiopulmonary resuscitation device for chest compression. It is operated manually but it does not pull up on the chest on the up stroke. The aim of this study was to compare the CPR RAD with standard manual compression in terms of chest compression quality in a manikin model.

Methods

Participants were randomly assigned to either the device or manual chest compression group. Each participant performed a maximum of 4 minutes of hands-only compression with or without the device. During chest compression, the following quality parameters from the manikin were recorded: compression rate, compression depth, and correctness of hand position.

Results

Duration of chest compression was significantly higher in device users compared with manual compression (223.93±36.53 vs 179.67±50.81 seconds; P<0.001). The mean compression depth did not differ in a statistically significant way between manual compression and device at 2 minutes (56.42±6.42 vs 54.25±5.32; P=0.052). During the first and second minutes, compression rate was higher in cases of standard compression (133.21±15.95 vs 108±9.45; P<0.001 and 127.41±27.77 vs 108.5±9.93; P<0.001). There was no statistically significant difference in the percentage of participants who employed compression that was too shallow or exhibited incorrect hand position.

Conclusion

The CPR RAD is more effective in chest compression compared with manual chest compression, as using the device led to better results in terms of fatigue reduction and correct compression rate than standard manual compression.

Effect of the Cardio First Angel™ device on CPR indices: a randomized controlled clinical trial

Background

A number of cardiopulmonary resuscitation (CPR) adjunct devices have been developed to improve the consistency and quality of manual chest compressions. We investigated whether a CPR feedback device would improve CPR quality and consistency, as well as patient survival.

Methods

We conducted a randomized controlled study of patients undergoing CPR for cardiac arrest in the mixed medical-surgical intensive care units of four academic teaching hospitals. Patients were randomized to receive either standard manual CPR or CPR using the Cardio First Angel™ CPR feedback device. Recorded variables included guideline adherence, CPR quality, return of spontaneous circulation (ROSC) rates, and CPR-associated morbidity.

Results

A total of 229 subjects were randomized; 149 were excluded; and 80 were included. Patient demographics were similar. Adherence to published CPR guidelines and CPR quality was significantly improved in the intervention group (p < 0.0001), as were ROSC rates (72 % vs. 35 %; p = 0.001). A significant decrease was observed in rib fractures (57 % vs. 85 %; p = 0.02), but not sternum fractures (5 % vs. 17 %; p = 0.15).

Conclusions

Use of the Cardio First Angel™ CPR feedback device improved adherence to published CPR guidelines and CPR quality, and it was associated with increased rates of ROSC. A decrease in rib but not sternum fractures was observed with device use. Further independent prospective validation is warranted to determine if these results are reproducible in other acute care settings.

Trial registration

ClinicalTrials.gov identifier: NCT02394977. Registered on 5 Mar 2015.

Short structured feedback training is equivalent to a mechanical feedback device in two-rescuer BLS: a randomised simulation study

BACKGROUND

Resuscitation guidelines encourage the use of cardiopulmonary resuscitation (CPR) feedback devices implying better outcomes after sudden cardiac arrest. Whether effective continuous feedback could also be given verbally by a second rescuer ("human feedback") has not been investigated yet. We, therefore, compared the effect of human feedback to a CPR feedback device.

METHODS

In an open, prospective, randomised, controlled trial, we compared CPR performance of three groups of medical students in a two-rescuer scenario. Group "sCPR" was taught standard BLS without continuous feedback, serving as control. Group "mfCPR" was taught BLS with mechanical audio-visual feedback (HeartStart MRx with Q-CPR-Technology™). Group "hfCPR" was taught standard BLS with human feedback. Afterwards, 326 medical students performed two-rescuer BLS on a manikin for 8 min. CPR quality parameters, such as "effective compression ratio" (ECR: compressions with correct hand position, depth and complete decompression multiplied by flow-time fraction), and other compression, ventilation and time-related parameters were assessed for all groups.

RESULTS

ECR was comparable between the hfCPR and the mfCPR group (0.33 vs. 0.35, p = 0.435). The hfCPR group needed less time until starting chest compressions (2 vs. 8 s, p < 0.001) and showed fewer incorrect decompressions (26 vs. 33 %, p = 0.044). On the other hand, absolute hands-off time was higher in the hfCPR group (67 vs. 60 s, p = 0.021).

CONCLUSIONS

The quality of CPR with human feedback or by using a mechanical audio-visual feedback device was similar. Further studies should investigate whether extended human feedback training could further increase CPR quality at comparable costs for training.

[Mechanical resuscitation assist devices]

In Germany 100,000-160,000 people suffer from out-of-hospital cardiac arrest (OHCA) annually. The incidence of cardiopulmonary resuscitation (CPR) after OHCA varies between emergency ambulance services but is in the range of 30-90 CPR attempts per 100,000 inhabitants per year. Basic life support (BLS) involving chest compressions and ventilation is the key measure of resuscitation. Rapid initiation and quality of BLS are the most critical factors for CPR success. Even healthcare professionals are not always able to ensure the quality of CPR measures. Consequently in recent years mechanical resuscitation devices have been developed to optimize chest compression and the resulting circulation. In this article the mechanical resuscitation devices currently available in Germany are discussed and evaluated scientifically in context with available literature. The ANIMAX CPR device should not be used outside controlled trials as no clinical results have so far been published. The same applies to the new device Corpuls CPR which will be available on the market in early 2014. Based on the current published data a general recommendation for the routine use of LUCAS™ and AutoPulse® CPR cannot be given. The preliminary data of the CIRC trial and the published data of the LINC trial revealed that mechanical CPR is apparently equivalent to good manual CPR. For the final assessment further publications of large randomized studies must be analyzed (e.g. the CIRC and PaRAMeDIC trials). However, case control studies, case series and small studies have already shown that in special situations and in some cases patients will benefit from the automatic mechanical resuscitation devices (LUCAS™, AutoPulse®). This applies especially to emergency services where standard CPR quality is far below average and for patients who require prolonged CPR under difficult circumstances. This might be true in cases of resuscitation due to hypothermia, intoxication and pulmonary embolism as well as for patients requiring transport or coronary intervention when cardiac arrest persists. Three prospective randomized studies and the resulting meta-analysis are available for active compression-decompression resuscitation (ACD-CPR) in combination with an impedance threshold device (ITD). These studies compared ACD-ITD-CPR to standard CPR and clearly demonstrated that ACD-ITD-CPR is superior to standard CPR concerning short and long-term survival with good neurological recovery after OHCA.

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 8min. 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.

Cardiopulmonary resuscitation quality: [corrected] improving cardiac resuscitation outcomes both inside and outside the hospital: a consensus statement from the American Heart Association

The "2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care" increased the focus on methods to ensure that high-quality cardiopulmonary resuscitation (CPR) is performed in all resuscitation attempts. There are 5 critical components of high-quality CPR: minimize interruptions in chest compressions, provide compressions of adequate rate and depth, avoid leaning between compressions, and avoid excessive ventilation. Although it is clear that high-quality CPR is the primary component in influencing survival from cardiac arrest, there is considerable variation in monitoring, implementation, and quality improvement. As such, CPR quality varies widely between systems and locations. Victims often do not receive high-quality CPR because of provider ambiguity in prioritization of resuscitative efforts during an arrest. This ambiguity also impedes the development of optimal systems of care to increase survival from cardiac arrest. This consensus statement addresses the following key areas of CPR quality for the trained rescuer: metrics of CPR performance; monitoring, feedback, and integration of the patient's response to CPR; team-level logistics to ensure performance of high-quality CPR; and continuous quality improvement on provider, team, and systems levels. Clear definitions of metrics and methods to consistently deliver and improve the quality of CPR will narrow the gap between resuscitation science and the victims, both in and out of the hospital, and lay the foundation for further improvements in the future.

Single rescuer exertion using a mechanical resuscitation device: a randomized controlled simulation study

OBJECTIVES

The goal of this experimental study was to investigate rescuer exertion when using "Animax," a manually operated hand-powered mechanical resuscitation device (MRD) for cardiopulmonary resuscitation (CPR), compared to standard basic life support (BLS).

METHODS

This was a prospective, open, randomized, crossover simulation study. After being trained, 80 medical students with substantial knowledge in BLS performed one-rescuer CPR using either the MRD or the standard BLS for 12-minute intervals in random order. The main outcome parameter was the heart rate pressure product (RPP) as an index of cardiac work. Secondary outcome parameters were physical exhaustion quantified by the Borg scale (measurement of perceived exertion), Nine Hole Peg Test (NHPT; measurement of fine motor skills), and capillary lactate concentration during testing.

RESULTS

While no significant difference could be found for the RPP, a significantly increased mean heart rate during the final minute of standard BLS compared to the MRD was found (139 ± 22 beats/min vs. 135 ± 26 beats/min, p = 0.027). By contrast, subjective exertion using the MRD was rated significantly higher on the Borg scale (15.1 ± 2.4 vs. 14.6 ± 2.6, p = 0.027). Mean serum lactate concentration was significantly higher when the MRD was used compared to standard BLS (3.4 ± 1.5 mmol/L vs. 2.1 ± 1.3 mmol/L, p ≤ 0.001).

CONCLUSIONS

Use of the MRD leads to a RPP of the rescuers comparable to standard BLS. These findings suggest that there is no clinically relevant reduction of exertion if this MRD is used by a single rescuer. If this kind of MRD is used for CPR, frequent changeovers with a second rescuer should be considered as the guidelines suggest for standard CPR.

Effective compression ratio--a new measurement of the quality of thorax compression during CPR

PURPOSE

Computer-based feedback systems for assessing the quality of cardiopulmonary resuscitation (CPR) are widely used these days. Recordings usually involve compression and ventilation dependent variables. Thorax compression depth, sufficient decompression and correct hand position are displayed but interpreted independently of one another. We aimed to generate a parameter, which represents all the combined relevant parameters of compression to provide a rapid assessment of the quality of chest compression-the effective compression ratio (ECR).

METHODS

The following parameters were used to determine the ECR: compression depth, correct hand position, correct decompression and the proportion of time used for chest compressions compared to the total time spent on CPR. Based on the ERC guidelines, we calculated that guideline compliant CPR (30:2) has a minimum ECR of 0.79. To calculate the ECR, we expanded the previously described software solution. In order to demonstrate the usefulness of the new ECR-parameter, we first performed a PubMed search for studies that included correct compression and no-flow time, after which we calculated the new parameter, the ECR.

RESULTS

The PubMed search revealed 9 trials. Calculated ECR values ranged between 0.03 (for basic life support [BLS] study, two helpers, no feedback) and 0.67 (BLS with feedback from the 6th minute).

CONCLUSION

ECR enables rapid, meaningful assessment of CPR and simplifies the comparability of studies as well as the individual performance of trainees. The structure of the software solution allows it to be easily adapted to any manikin, CPR feedback devices and different resuscitation guidelines (e.g. ILCOR, ERC).