The use of CPR feedback/prompt devices during training and CPR performance: A systematic review

Variability in quality of chest compressions provided during simulated cardiac arrest across nine pediatric institutions

AIM

The variability in quality of CPR provided during cardiac arrest across pediatric institutions is unknown. We aimed to describe the degree of variability in the quality of CPR across 9 pediatric institutions, and determine if variability across sites would be affected by Just-in-Time CPR training and/or visual feedback during simulated cardiac arrest.

METHODS

We conducted secondary analyses of data collected from a prospective, multi-center trial. Participants were equally randomized to either: (1) No intervention; (2) Real-time CPR visual feedback during cardiac arrest or (3) Just-in-Time CPR training. We report the variability in median chest compression depth and rate across institutions, and the variability in the proportion of 30-s epochs of CPR meeting 2010 American Heart Association guidelines for depth and rate.

RESULTS

We analyzed data from 528 epochs in the no intervention group, 552 epochs in the visual feedback group, and 525 epochs in the JIT training group. In the no intervention group, compression depth (median range 22.2-39.2mm) and rate (median range 116.0-147.6 min(-1)) demonstrated significant variability between study sites (p<0.001). The proportion of compressions with adequate depth (0-11.5%) and rate (0-60.5%) also varied significantly across sites (p<0.001). The variability in compression depth and rate persisted despite use of real-time visual feedback or JIT training (p<0.001).

CONCLUSION

The quality of CPR across multiple pediatric institutions is variable. Variability in CPR quality across institutions persists even with the implementation of a Just-in-Time training session and visual feedback for CPR quality during simulated cardiac arrest.

Impact of simulation training on Jordanian nurses' performance of basic life support skills: A pilot study

BACKGROUND

Providing efficient basic life support (BLS) training is crucial for practicing nurses who provide direct patient care. Nevertheless, data addressing the impact of BLS courses on the skills and performance of Jordanian nurses are scarce. This study aimed to assess the effectiveness of a BLS simulation training on Jordanian nurses' skill improvement in cardiopulmonary resuscitation.

METHODS

A prospective quasi-experimental, single group pretest-posttest design was used to study the effect of BLS simulation; using a 9-item checklist; on the spot training; American Heart Association, on a group of Jordanian nurses. A pre-test was conducted following a CPR scenario to test the skills using 9-item checklist extrapolated from the American Heart Association guidelines. After debriefing, an interactive on spot training was provided. Later, participants undertook an unscheduled post-test after four weeks that included the same nine items.

RESULTS

Thirty registered nurses with a mean clinical experience of 6.1years participated in the study. Comparing pre-test (M=4.6, SD=2.9, range=0 to 9) with post-test results (M=7.5, SD=1.7, range=4 to 9) showed an overall improvement in skills and BLS scores after the simulation training program (t=7.4, df=29, p<0.0001).

CONCLUSIONS

BLS simulation training sessions are associated with significant improvement in skills and performance among Jordanian nurses. A refreshment BLS training session for nurses is highly recommended to guarantee nurses' preparedness in actual CPR scenarios.

An investigation of thrust, depth and the impedance cardiogram as measures of cardiopulmonary resuscitation efficacy in a porcine model of cardiac arrest

OBJECTIVE

Optimising the depth and rate of applied chest compressions following out of hospital cardiac arrest is crucial in maintaining end organ perfusion and improving survival. The impedance cardiogram (ICG) measured via defibrillator pads produces a characteristic waveform during chest compressions with the potential to provide feedback on cardiopulmonary resuscitation (CPR) and enhance performance. The objective of this pre-clinical study was to investigate the relationship between mechanical and physiological markers of CPR efficacy in a porcine model and examine the strength of correlation between the ICG amplitude, compression depth and end-tidal CO2 (ETCO2).

METHODS

Two experiments were performed using 24 swine (12 per experiment). For experiment 1, ventricular fibrillation (VF) was induced and mechanical CPR commenced at varying thrusts (0-60 kg) for 2 min intervals. Chest compression depth was recorded using a Philips QCPR device with additional recording of invasive physiological parameters: systolic blood pressure, ETCO2, cardiac output and carotid flow. For experiment 2, VF was induced and mechanical CPR commenced at varying depths (0-5 cm) for 2 min intervals. The ICG was recorded via defibrillator pads attached to the animal's sternum and connected to a Heartsine 500 P defibrillator. ICG amplitude, chest compression depth, systolic blood pressure and ETCO2 were recorded during each cycle. In both experiments the within-animal correlation between the measured parameters was assessed using a mixed effect model.

RESULTS

In experiment 1 moderate within-animal correlations were observed between physiological parameters and compression depth (r=0.69-0.77) and thrust (r=0.66-0.82). A moderate correlation was observed between compression depth and thrust (r=0.75). In experiment 2 a strong within-animal correlation and moderate overall correlations were observed between ICG amplitude and compression depth (r=0.89, r=0.79) and ETCO2 (r=0.85, r=0.64).

CONCLUSION

In this porcine model of induced cardiac arrest moderate within animal correlations were observed between mechanical and physiological markers of chest compression efficacy demonstrating the challenge in utilising a single mechanical metric to quantify chest compression efficacy. ICG amplitude demonstrated strong within animal correlations with compression depth and ETCO2 suggesting its potential utility to provide CPR feedback in the out of hospital setting to improve performance.

Mechanical versus manual chest compression for out-of-hospital cardiac arrest (PARAMEDIC): a pragmatic, cluster randomised controlled trial

BACKGROUND

Mechanical chest compression devices have the potential to help maintain high-quality cardiopulmonary resuscitation (CPR), but despite their increasing use, little evidence exists for their effectiveness. We aimed to study whether the introduction of LUCAS-2 mechanical CPR into front-line emergency response vehicles would improve survival from out-of-hospital cardiac arrest.

METHODS

The pre-hospital randomised assessment of a mechanical compression device in cardiac arrest (PARAMEDIC) trial was a pragmatic, cluster-randomised open-label trial including adults with non-traumatic, out-of-hospital cardiac arrest from four UK Ambulance Services (West Midlands, North East England, Wales, South Central). 91 urban and semi-urban ambulance stations were selected for participation. Clusters were ambulance service vehicles, which were randomly assigned (1:2) to LUCAS-2 or manual CPR. Patients received LUCAS-2 mechanical chest compression or manual chest compressions according to the first trial vehicle to arrive on scene. The primary outcome was survival at 30 days following cardiac arrest and was analysed by intention to treat. Ambulance dispatch staff and those collecting the primary outcome were masked to treatment allocation. Masking of the ambulance staff who delivered the interventions and reported initial response to treatment was not possible. The study is registered with Current Controlled Trials, number ISRCTN08233942.

FINDINGS

We enrolled 4471 eligible patients (1652 assigned to the LUCAS-2 group, 2819 assigned to the control group) between April 15, 2010 and June 10, 2013. 985 (60%) patients in the LUCAS-2 group received mechanical chest compression, and 11 (<1%) patients in the control group received LUCAS-2. In the intention-to-treat analysis, 30 day survival was similar in the LUCAS-2 group (104 [6%] of 1652 patients) and in the manual CPR group (193 [7%] of 2819 patients; adjusted odds ratio [OR] 0·86, 95% CI 0·64-1·15). No serious adverse events were noted. Seven clinical adverse events were reported in the LUCAS-2 group (three patients with chest bruising, two with chest lacerations, and two with blood in mouth). 15 device incidents occurred during operational use. No adverse or serious adverse events were reported in the manual group.

INTERPRETATION

We noted no evidence of improvement in 30 day survival with LUCAS-2 compared with manual compressions. On the basis of ours and other recent randomised trials, widespread adoption of mechanical CPR devices for routine use does not improve survival.

FUNDING

National Institute for Health Research HTA - 07/37/69.

Factors affecting the accuracy of chest compression depth estimation

OBJECTIVE

We aimed to estimate the accuracy of visual estimation of chest compression depth and identify potential factors affecting accuracy.

METHODS

This simulation study used a basic life support mannequin, the Ambu man. We recorded chest compression with 7 different depths from 1 to 7 cm. Each video clip was recorded for a cycle of compression. Three different viewpoints were used to record the video. After filming, 25 clips were randomly selected. Health care providers in an emergency department were asked to estimate the depth of compressions while watching the selected video clips. Examiner determinants such as experience and cardiopulmonary resuscitation training and environment determinants such as the location of the camera (examiner) were collected and analyzed. An estimated depth was considered correct if it was consistent with the one recorded. A multivariate analysis predicting the accuracy of compression depth estimation was performed.

RESULTS

Overall, 103 subjects were enrolled in the study; 42 (40.8%) were physicians, 56 (54.4%) nurses, and 5 (4.8%) emergency medical technicians. The mean accuracy was 0.89 (standard deviation, 0.76). Among examiner determinants, only subjects' occupation and clinical experience showed significant association with outcome (P=0.03 and P=0.08, respectively). All environmental determinants showed significant association with the outcome (all P<0.001). Multivariate analysis showed that accuracy rate was significantly associated with occupation, camera position, and compression depth.

CONCLUSIONS

The accuracy rate of chest compression depth estimation was 0.89 and was significantly related with examiner's occupation, camera view position, and compression depth.

Reliability and accuracy of the thoracic impedance signal for measuring cardiopulmonary resuscitation quality metrics

AIM

To determine the accuracy and reliability of the thoracic impedance (TI) signal to assess cardiopulmonary resuscitation (CPR) quality metrics.

METHODS

A dataset of 63 out-of-hospital cardiac arrest episodes containing the compression depth (CD), capnography and TI signals was used. We developed a chest compression (CC) and ventilation detector based on the TI signal. TI shows fluctuations due to CCs and ventilations. A decision algorithm classified the local maxima as CCs or ventilations. Seven CPR quality metrics were computed: mean CC-rate, fraction of minutes with inadequate CC-rate, chest compression fraction, mean ventilation rate, fraction of minutes with hyperventilation, instantaneous CC-rate and instantaneous ventilation rate. The CD and capnography signals were accepted as the gold standard for CC and ventilation detection respectively. The accuracy of the detector was evaluated in terms of sensitivity and positive predictive value (PPV). Distributions for each metric computed from the TI and from the gold standard were calculated and tested for normality using one sample Kolmogorov-Smirnov test. For normal and not normal distributions, two sample t-test and Mann-Whitney U test respectively were applied to test for equal means and medians respectively. Bland-Altman plots were represented for each metric to analyze the level of agreement between values obtained from the TI and gold standard.

RESULTS

The CC/ventilation detector had a median sensitivity/PPV of 97.2%/97.7% for CCs and 92.2%/81.0% for ventilations respectively. Distributions for all the metrics showed equal means or medians, and agreements >95% between metrics and gold standard was achieved for most of the episodes in the test set, except for the instantaneous ventilation rate.

CONCLUSION

With our data, the TI can be reliably used to measure all the CPR quality metrics proposed in this study, except for the instantaneous ventilation rate.

Performance of chest compressions with the use of a new audio-visual feedback device: a randomized manikin study in health care professionals

AIM

Optimal depth (50-60mm) and rate (100-120min(-1)) of chest compressions (CC) is the prerequisite of effective cardiopulmonary resuscitation (CPR). However, insufficient CC during CPR are common even among health care professionals. We sought to evaluate if CC are more effective with the use of a novel feedback device compared to standard CC. Primary endpoints were absolute percentage of correct CC of all CC (correct rate and correct depth, classified as "optimal" CC), and the percentage of CC in target rate and percentage of CC in target depth.

METHODS

63 healthcare professionals performed CC on a manikin with the use of a novel feedback device. The device provides audio-visual information about compression depth and rate. Each participant performed two minutes of CC with and without feedback. Participants were randomized into two groups that performed either CC with feedback first, followed by a trial without feedback, or vice versa. All participants answered a short questionnaire on self-estimation of CC performance.

RESULTS

The absolute percentage of optimal compressions of all compressions has increased from 27.9±28.8% to 47.6±33.5% (p<0.001) with use of the device. Furthermore, a significant increase of the percentage of CC in target depth (35.9±30.6% without vs. 54.8±33.5% with the device, p=0.003) and in target rate (70.5±37.7% without vs. 82.7±27.8 with the device, p=0.039) were observed.

CONCLUSION

This novel feedback device significantly improved the quality of CC in health care professionals.

A new method for feedback on the quality of chest compressions during cardiopulmonary resuscitation

Quality of cardiopulmonary resuscitation (CPR) improves through the use of CPR feedback devices. Most feedback devices integrate the acceleration twice to estimate compression depth. However, they use additional sensors or processing techniques to compensate for large displacement drifts caused by integration. This study introduces an accelerometer-based method that avoids integration by using spectral techniques on short duration acceleration intervals. We used a manikin placed on a hard surface, a sternal triaxial accelerometer, and a photoelectric distance sensor (gold standard). Twenty volunteers provided 60 s of continuous compressions to test various rates (80–140 min⁻¹), depths (3–5 cm), and accelerometer misalignment conditions. A total of 320 records with 35312 compressions were analysed. The global root-mean-square errors in rate and depth were below 1.5 min⁻¹ and 2 mm for analysis intervals between 2 and 5 s. For 3 s analysis intervals the 95% levels of agreement between the method and the gold standard were within −1.64–1.67 min⁻¹ and −1.69–1.72 mm, respectively. Accurate feedback on chest compression rate and depth is feasible applying spectral techniques to the acceleration. The method avoids additional techniques to compensate for the integration displacement drift, improving accuracy, and simplifying current accelerometer-based devices.

Effective CPR Procedure With Real Time Evaluation and Feedback Using Smartphones

Timely cardio pulmonary resuscitation (CPR) can mean the difference between life and death. A trained person may not be available at emergency sites to give CPR. Normally, a 9-1-1 operator gives verbal instructions over the phone to a person giving CPR. In this paper, we discuss the use of smartphones to assist in administering CPR more efficiently and accurately. The two important CPR parameters are the frequency and depth of compressions. In this paper, we used smartphones to calculate these factors and to give real-time guidance to improve CPR. In addition, we used an application to measure oxygen saturation in blood. If blood oxygen saturation falls below an acceptable threshold, the person giving CPR can be asked to do mouth-to-mouth breathing. The 9-1-1 operator receives this information real time and can further guide the person giving CPR. Our experiments show accuracy >90% for compression frequency, depth, and oxygen saturation.

Every second counts: innovations to increase timely defibrillation rates

Early defibrillation is an essential step in the "chain of survival" for patients with in-hospital cardiac arrest. To increase the rate of early defibrillation by nurse first responders in noncritical care areas, our institution employed a quality resuscitation consultant, implemented nursing education programs, and standardized equipment and practices. Automated external defibrillator application by nurse first responders prior to advanced cardiac life support team arrival has improved from 15% in 2011 to 76% in 2013 (P < .001).

Automatic detection of chest compressions for the assessment of CPR-quality parameters

AIM

Accurate chest compression detection is key to evaluate cardiopulmonary resuscitation (CPR) quality. Two automatic compression detectors were developed, for the compression depth (CD), and for the thoracic impedance (TI). The objective was to evaluate their accuracy for compression detection and for CPR quality assessment.

METHODS

Compressions were manually annotated using the force and ECG in 38 out-of-hospital resuscitation episodes, comprising 869 min and 67,402 compressions. Compressions were detected using a negative peak detector for the CD. For the TI, an adaptive peak detector based on the amplitude and duration of TI fluctuations was used. Chest compression rate (CC-rate) and chest compression fraction (CCF) were calculated for the episodes and for every minute within each episode. CC-rate for rescuer feedback was calculated every 8 consecutive compressions.

RESULTS

The sensitivity and positive predictive value were 98.4% and 99.8% using CD, and 94.2% and 97.4% using TI. The mean CCF and CC-rate obtained from both detectors showed no significant differences with those obtained from the annotations (P>0.6). The Bland-Altman analysis showed acceptable 95% limits of agreement between the annotations and the detectors for the per-minute CCF, per-minute CC-rate, and CC-rate for feedback. For the detector based on TI, only 3.7% of CC-rate feedbacks had an error larger than 5%.

CONCLUSION

Automatic compression detectors based on the CD and TI signals are very accurate. In most cases, episode review could safely rely on these detectors without resorting to manual review. Automatic feedback on rate can be accurately done using the impedance channel.

Cardiac arrest teams and medical emergency teams in Finland: a nationwide cross-sectional postal survey

BACKGROUND

The implementation, characteristics and utilisation of cardiac arrest teams (CATs) and medical emergency teams (METs) in Finland are unknown. We aimed to evaluate how guidelines on advanced in-hospital resuscitation have been translated to practice.

METHODS

A cross-sectional postal survey including all public hospitals providing anaesthetic services.

RESULTS

Of the 55 hospitals, 51 (93%) participated in the study. All hospitals with intensive care units (university and central hospitals, n = 24) took part. In total, 88% of these hospitals (21/24) and 30% (8/27) of the small hospitals had CATs. Most hospitals with CATs (24/29) recorded team activations. A structured debriefing after a resuscitation attempt was organised in only one hospital. The median incidence of in-hospital cardiac arrest in Finland was 1.48 (Q1 = 0.93, Q3 = 1.93) per 1000 hospital admissions. METs had been implemented in 31% (16/51) of the hospitals. A physician participated in MET activation automatically in half (8/16) of the teams. Operating theatres (13/16), emergency departments (10/16) and paediatric wards (7/16) were the most common sites excluded from the METs' operational areas. The activation thresholds for vital signs varied between hospitals. The lower upper activation threshold for respiratory rate was associated with a higher MET activation rate. The national median MET activation rate was 2.3 (1.5, 4.8) per 1000 hospital admissions and 1.5 (0.96, 4.0) per every cardiac arrest.

CONCLUSIONS

Current guidelines emphasise the preventative actions on in-hospital cardiac arrest. Practices are changing accordingly but are still suboptimal especially in central and district hospitals. Unified guidelines on rapid response systems are required.

Effect of mattress and bed frame deflection on real chest compression depth measured with two CPR sensors

AIM

Implementation of chest compression (CC) feedback devices with a single force and deflection sensor (FDS) may improve the quality of CPR. However, CC depth may be overestimated if the patient is on a compliant surface. We have measured the true CC depth during in-hospital CPR using two FDSs on different bed and mattress types.

METHODS

This prospective observational study was conducted at Tampere University Hospital between August 2011 and September 2012. During in-hospital CPR one FDS was placed between the rescuer's hand and the patient's chest, with the second attached to the backboard between the patient's back and the mattress. The real CC depth was calculated as the difference between the total depth from upper FDS to lower FDS.

RESULTS

Ten cardiac arrests on three different bed and mattress types yielded 10,868 CCs for data analyses. The mean (SD) mattress/bed frame effect was 12.8 (4) mm on a standard hospital bed with a gel mattress, 12.4 (4) mm on an emergency room stretcher with a thin gel mattress and 14.1 (3) mm on an ICU bed with an emptied air mattress. The proportion of CCs with an adequate depth (≥50 mm) decreased on all mattress types after compensating for the mattress/bed frame effect from 94 to 64%, 98 to 76% and 91 to 17%, in standard hospital bed, emergency room stretcher and ICU bed, respectively (p<0.001).

CONCLUSION

The use of FDS without real-time correction for deflection may result in CC depth not reaching the recommended depth of 50 mm.

Schoolchildren as life savers: at what age do they become strong enough?

OBJECTIVE

It is not clear when schoolchildren become enough strong to perform good quality chest compressions (CC). Our purpose was to assess CC quality in schoolchildren.

METHODS

721 children, 10-15 years old (YO) participated in 1 h hands-on training session. Subjects were tested during performing 2 min of continuous CC by means of Laerdal Resusci Anne(®) with Skillreporter(®), without feedback.

RESULTS

Mean compression depth (MCD) increased with age, from 30.7 mm in 10YO to 42.9 mm in 15YO (p<0.05) and was related to height, weight, and BMI. Boys delivered significantly deeper CC than girls in the 10, 13, 14 and 15YO groups (p<0.001). The percentage of children who achieved the MCD goal (50-60 mm), increased with age, from 0.0% at 10 years to 26.5% at 15 years (p<0.001). Mean compression rate (MCR) ranged from 121 min(-1) in 15YO to 134 min(-1) in 12YO. The percentage of children who achieved a CC rate inside the goal (100-120 min(-1)), ranged from 20.3% in 11YO to 31.0% in 15YO. Correct CC fraction was low and ranged from 2% in the 10YO to 22% in the 15YO (p<0.05). Children older than 13YO obtained better results than younger ones for all analyzed variables (p<0.001). Performance decreased with time: 12% of children achieved >50% of correct CC fraction in first minute, while only 5% did it in second minute (p<0.001).

CONCLUSIONS

In schoolchildren, age, sex and anthropometry are significant CPR quality factors. Although quality increases with age, their global performance is poor. Thirteen years is the minimum age to be able to achieve a minimum CPR quality similar to the one adult possess. CPR performance in schoolchildren significantly deteriorates within 60 s.

The quality of manual chest compressions during transport--effect of the mattress assessed by dual accelerometers

BACKGROUND

The quality of cardiopulmonary resuscitation (CPR) has an impact on survival. The quality may be impaired if the patient needs to be transported to the hospital with ongoing CPR. The aim of this study was to analyse whether the quality of CPR can be improved during transportation by using real-time audiovisual feedback. In addition, we sought to evaluate the real compression depths taking into account the mattress and stretcher effect.

METHODS

Paramedics (n = 24) performed standard CPR on a Resusci Anne Mannequin in a moving ambulance. Participants were instructed to perform CPR according to European Resuscitation Council Resuscitation guidelines 2010. Each pair acted as their own controls performing CPR first without and then with the feedback device. Compression depth, rate and no-flow fraction and also the mattress effect were recorded by using dual accelerometers by two Philips, HeartStart MRx Q-CPR defibrillators.

RESULTS

In the feedback phase, the mean compression depth increased from 51 (10) to 56 (5) mm (P < 0.001), and the percentage of compression fractions with adequate depth was 60% vs. 89% (P < 0.001). However, taking account of the mattress effect, the real depth was only 41 (8) vs. 44 (5) mm without and with feedback, respectively (P < 0.001). The values for compression rate did not differ.

CONCLUSIONS

CPR quality was good during transportation in general. However, the results suggest that the feedback system improves CPR quality. Dual accelerometer measurements show, on the other hand, that the mattress effect may be a clinically relevant impediment to high quality CPR.

Debriefing after resuscitation

PURPOSE OF REVIEW

Evidence of suboptimal cardiopulmonary resuscitation (CPR) delivery in practice has driven interest in strategies to improve CPR quality. Early data suggest that debriefing may be an effective strategy. In this review, we analyse types of debriefing and the evidence to support their usage.

RECENT FINDINGS

There is a general lack of standardization in terminology and methods used for debriefing that limits evaluation. Debriefing interventions generally take two different formats. Hot debriefing is one where individuals or teams are provided with debriefing immediately after the event. Although perhaps the most widely used and easiest to implement, research evidence for its effectiveness is scant. Cold debriefing, where individuals or teams are provided with feedback sometime after the event, is associated with improvements in process and patient outcomes. Such feedback usually involves the use of objective performance data, such as defibrillator downloads or videotape records. Before and after cohort studies have found that both verbal debriefing in groups and individual written feedback seem to be associated with an improvement in performance.

SUMMARY

Debriefing is a useful strategy to improve resuscitation performance, but the optimal delivery method remains unclear. Future high-quality research is required to identify the most effective form of debriefing.

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.

First quantitative analysis of cardiopulmonary resuscitation quality during in-hospital cardiac arrests of young children

AIM

The objective of this study is to report, for the first time, quantitative data on CPR quality during the resuscitation of children under 8 years of age. We hypothesized that the CPR performed would often not achieve 2010 Pediatric Basic Life Support (BLS) Guidelines, but would improve with the addition of audiovisual feedback.

METHODS

Prospective observational cohort evaluating CPR quality during chest compression (CC) events in children between 1 and 8 years of age. CPR recording defibrillators collected CPR data (rate (CC/min), depth (mm), CC fraction (CCF), leaning (%>2.5 kg.)). Audiovisual feedback was according to 2010 Guidelines in a subset of patients. The primary outcome, "excellent CPR" was defined as a CC rate ≥ 100 and ≤ 120 CC/min, depth ≥ 50 mm, CCF >0.80, and <20% of CC with leaning.

RESULTS

8 CC events resulted in 285 thirty-second epochs of CPR (15,960 CCs). Percentage of epochs achieving targets was 54% (153/285) for rate, 19% (54/285) for depth, 88% (250/285) for CCF, 79% (226/285) for leaning, and 8% (24/285) for excellent CPR. The median percentage of epochs per event achieving targets increased with audiovisual feedback for rate [88 (IQR: 79, 94) vs. 39 (IQR 18, 62) %; p=0.043] and excellent CPR [28 (IQR: 7.2, 52) vs. 0 (IQR: 0, 1) %; p=0.018].

CONCLUSIONS

In-hospital pediatric CPR often does not meet 2010 Pediatric BLS Guidelines, but compliance is better when audiovisual feedback is provided to rescuers.

Real-time audiovisual feedback system in a physician-staffed helicopter emergency medical service in Finland: the quality results and barriers to implementation

OBJECTIVES

To evaluate the quality of cardiopulmonary resuscitation (CPR) in a physician staffed helicopter emergency medical service (HEMS) using a monitor-defibrillator with a quality analysis feature. As a post hoc analysis, the potential barriers to implementation were surveyed.

METHODS

The quality of CPR performed by the HEMS from November 2008 to April 2010 was analysed. To evaluate the implementation rate of quality analysis, the HEMS database was screened for all cardiac arrest missions during the study period. As a consequence of the observed low implementation rate, a survey was sent to physicians working in the HEMS to evaluate the possible reasons for not utilizing the automated quality analysis feature.

RESULTS

During the study period, the quality analysis was used for 52 out of 187 patients (28%). In these cases the mean compression depth was < 40 mm in 46% and < 50 mm in 96% of the 1-min analysis intervals, but otherwise CPR quality corresponded with the 2005 resuscitation guidelines. In particular, the no-flow fraction was remarkably low 0.10 (0.07, 0.16). The most common reasons for not using quality-controlled CPR were that the device itself was not taken to the scene, or not applied to the patient, because another EMS unit was already treating the patient with another defibrillator.

CONCLUSIONS

When quality-controlled CPR technology was used, the indicators of good quality CPR as described in the 2005 resuscitation guidelines were mostly achieved albeit with sufficient compression depth. The use of the well-described technology in improving patient care was low. Wider implementation of the automated quality control and feedback feature in defibrillators could further improve the quality of CPR on the field.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT00951704).

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

Deeper chest compression - more complications for cardiac arrest patients?

AIM OF THE STUDY

Sternal and rib fractures are frequent complications caused by chest compressions during cardiopulmonary resuscitation (CPR). This study aimed to investigate the potential association of CPR-related thoracic and abdominal injuries and compression depth measured with an accelerometer.

METHODS

We analysed the autopsy records, CT scans or chest radiographs of 170 adult patients, suffering in-hospital cardiac arrest at the Tampere University Hospital during the period 2009-2011 to investigate possible association of chest compressions and iatrogenic injuries. The quality of manual compressions during CPR was recorded on a Philips, HeartStart MRx Q-CPR™-defibrillator.

RESULTS

Patients were 110 males and 60 females. Injuries were found in 36% of male and 23% of female patients. Among male patients CPR-related injuries were associated with deeper mean - and peak compression depths (p<0.05). No such association was observed in women. The frequency of injuries in mean compression depth categories <5, 5-6 and >6 cm, was 28%, 27% and 49% (p=0.06). Of all patients 27% sustained rib fractures, 11% sternal fracture and eight patients had haematomas/ruptures in the myocardium. In addition, we observed one laceration of the stomach without bleeding, one ruptured spleen, one mediastinal haemorrhage and two pneumothoraxes.

CONCLUSION

The number of iatrogenic injuries in male patients was associated with chest compressions during cardiopulmonary resuscitation increased as the measured compression depth exceeded 6 cm. While there is an increased risk of complications with deeper compressions it is important to realize that the injuries were by and large not fatal.

Motion detection technology as a tool for cardiopulmonary resuscitation (CPR) quality training: a randomised crossover mannequin pilot study

INTRODUCTION

Outcome after cardiac arrest is dependent on the quality of chest compressions (CC). A great number of devices have been developed to provide guidance during CPR. The present study evaluates a new CPR feedback system (Mini-VREM: Mini-Virtual Reality Enhanced Mannequin) designed to improve CC during training.

METHODS

Mini-VREM system consists of a Kinect(®) (Microsoft, Redmond, WA, USA) motion sensing device and specifically developed software to provide audio-visual feedback. Mini-VREM was connected to a commercially available mannequin (Laerdal Medical, Stavanger, Norway). Eighty trainees (healthcare professionals and lay people) volunteered in this randomised crossover pilot study. All subjects performed a 2 min CC trial, 1h pause and a second 2 min CC trial. The first group (FB/NFB, n=40) performed CC with Mini-VREM feedback (FB) followed by CC without feedback (NFB). The second group (NFB/FB, n=40) performed vice versa. Primary endpoints: adequate compression (compression rate between 100 and 120 min(-1) and compression depth between 50 and 60mm); compressions rate within 100-120 min(-1); compressions depth within 50-60mm.

RESULTS

When compared to the performance without feedback, with Mini-VREM feedback compressions were more adequate (FB 35.78% vs. NFB 7.27%, p<0.001) and more compressions achieved target rate (FB 72.04% vs. 31.42%, p<0.001) and target depth (FB 47.34% vs. 24.87%, p=0.002). The participants perceived the system to be easy to use with effective feedback.

CONCLUSIONS

The Mini-VREM system was able to improve significantly the CC performance by healthcare professionals and by lay people in a simulated CA scenario, in terms of compression rate and depth.