Quality of cardiopulmonary resuscitation on manikins: on the floor and in the bed

Efficacy of in-bed chest compressions depending on provider position during in-hospital cardiac arrest: a controlled manikin study

BACKGROUND

In contrast to the pre-hospital environment, patients with in-hospital cardiac arrest are usually lying in a hospital bed. Interestingly, there are no current recommendations for optimal provider positioning. The present study evaluates in bed chest compression quality in different provider positions during in-hospital-cardiac-arrest.

METHODS

Paramedics conducted four resuscitation scenarios: manikin lying on the floor with provider position kneeling next to the manikin (control group), manikin lying in a hospital bed with the provider kneeling astride, kneeling beside or standing next to the manikin. A resuscitation board was not used according to the current guideline recommendations. Quality of resuscitation, compression depth, compression rate and percentage of compressions with complete chest rebound were recorded. Afterwards, the paramedics were asked about subjective efficiency and fatigue. Data were analyzed using Generalized-Linear-Mixed-Models and, in addition, by non-parametric Friedman test.

RESULTS

A total of 60 participants were recruited. The total quality of chest compressions was significantly higher in floor-based control position compared to the standing (P<.001) and both kneeling positions (P<.05). Also, the compression depth was significantly more guideline compliant in the control (P<.001) and the kneeling position (P<.05) compared to the standing position. The compression frequency as well as the complete chest wall recoil did not differ significantly. The standing position was rated as more fatiguing than the other positions (p≤0.001), kneeling beside as subjectively more efficient than the standing position (P<0.001).

CONCLUSIONS

In case of an in-bed resuscitation, high quality chest compressions are possible. Kneeling astride or beside the patient should be preferred because these positions demonstrated a good chest compression quality and were more efficient and less exhausting.

Effectiveness of Lay Bystander Hands-Only Cardiopulmonary Resuscitation on a Mattress versus the Floor: A Randomized Cross-Over Trial

STUDY OBJECTIVE

Bystander cardiopulmonary resuscitation increases the likelihood of out-of-hospital cardiac arrest survival by more than two-fold. A common barrier to the prompt initiation of compressions is moving victims to the floor, but compression quality on a "floor" versus a "mattress" has not been tested among lay bystanders.

METHODS

We conducted a prospective, randomized, cross-over trial comparing lay bystander compression quality using a manikin on a bed versus the floor. Participants included adults without professional health care training. We randomized participants to the order of manikin placement, either on a mattress or on the floor. For both, participants were instructed to perform 2 minutes of chest compressions on a cardiopulmonary resuscitation Simon manikin Gaumard (Gaumard Scientific, Miami, FL). The primary outcome was mean compression depth (cm) over 2 minutes. We fit a linear regression model adjusted for scenario order, age, sex, and body mass index with robust standard errors to account for repeated measures and reported mean differences with 95% confidence intervals (CIs).

RESULTS

Our sample of 80 adults was 66% female with a mean age of 50.5 years (SD 18.2). The mean compression depth on the mattress was 2.9 cm (SD 2.3) and 3.5 cm (SD 2.2) on the floor, a mean difference of 0.58 cm (95% CI 0.18, 0.98). Compression depth fell below the 5 to 6 cm depth recommended by the American Heart Association on both surfaces. In the adjusted model, the mean depth was greater when the manikin was on the floor than the mattress (adjusted mean difference 0.62 cm; 95% CI 0.23 to 1.01), and mean depth was less for females than males (adjusted mean difference -1.42 cm, 95% CI -2.59, -0.25). In addition, the difference in compression depth was larger for female participants (mean difference 0.94 cm; 95% CI 0.54, 1.34) than for male participants (mean difference -0.01 cm; 95% CI -0.80, 0.78), and the interaction was statistically significant (P = .04).

CONCLUSION

The mean compression depth was significantly smaller on the mattress and with female bystanders. Further research is needed to understand the benefit of moving out-of-hospital cardiac arrest victims to the floor relative to the detrimental effect of delaying chest compressions.

[Basic life support]

The European Resuscitation Council has produced these basic life support guidelines, which are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. The topics covered include cardiac arrest recognition, alerting emergency services, chest compressions, rescue breaths, automated external defibrillation (AED), cardiopulmonary resuscitation (CPR) quality measurement, new technologies, safety, and foreign body airway obstruction.

European Resuscitation Council Guidelines 2021: Basic Life Support

The European Resuscitation Council has produced these basic life support guidelines, which are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. The topics covered include cardiac arrest recognition, alerting emergency services, chest compressions, rescue breaths, automated external defibrillation (AED), CPR quality measurement, new technologies, safety, and foreign body airway obstruction.

Implementation of Chest Compression for Cardiac Arrest Patient in Indonesia: True or False

Introduction: The highest cause of death is cardiac arrest. Proper manual chest compression will increase survival of cardiac arrest. The aim of this study was to know the implementation of chest compressions for cardiac arrest patient in Indonesia.Methods: This study used a descriptive quantitative design. The samples were nurse and code blue team when performing manual chest compression to 74 patients experiencing cardiac arrest. The sample have body mass index (BMI) > 20. Research was conducted in two hospitals in Java, Indonesia.  Implementation of chest compression is measured based on depth accuracy. Depth accuracy of chest compressions was assessed based on the comparison of the number of R waves with a height >10 mV on the bedside monitor with the number of chest compressions performed. The data were analyzed descriptively (mean, median, mode, standard deviation, and variances).Results: Result of this study is the mean of accuracy of compression depth is 75.97%. The result shows accuracy of compression depth on manual chest compression still under the American Heart Association (AHA) recommendation of 80%, because chest compression rate are not standardized. Chest compression rates are between 100-160 rates/minute, while AHA’s recommendations are 100-120 rates/minute. High compression speed causes a decrease in accuracy of chest compressions depth.Conclusion: In conclusion, the implementation of chest compressions in Indonesia if measured based on accuracy of compression depth is not effective. Nurses and the code blue team have to practice considering the use of cardiac resuscitation aids.

Adult Basic Life Support: International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care Science With Treatment Recommendations on basic life support summarizes evidence evaluations performed for 20 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 3 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Adult Basic Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This2020 International Consensus on Cardiopulmonary Resuscitation(CPR)and Emergency Cardiovascular Care Science With Treatment Recommendationson basic life support summarizes evidence evaluations performed for 22 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 5 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Effect of using a home-bed mattress on bystander chest compression during out-of-hospital cardiac arrest

Background:

Bystander cardiopulmonary resuscitation is a key component of life-saving after an out-of-hospital cardiac arrest. In the pre-arrival instructions for out-of-hospital cardiac arrest, it is recommended that the patient be laid on a flat floor. However, the most common reason for not performing cardiopulmonary resuscitation is that the bystander could not move the patient.

Objectives:

This study aim to investigate the effects of using a home-bed mattress on the quality of chest compression.

Methods:

In this prospective, randomized study, chest compression without ventilation was performed for 4 min on a Resusci Anne manikin placed on a flat floor or on three types of home-bed mattresses (hard, medium and soft). Chest compression depth, chest compression rate and chest recoil were measured from the manikin with the Laerdal PC Skill Reporting System, and changes in chest compression quality using the four different surfaces were compared.

Results:

Thirty participants were enrolled to perform chest compression. There was no significant difference in chest compression depth and depth accuracy between the four surfaces. The median chest compression rates were 108.1 ± 8.5, 107.0 ± 8.3, 103.3 ± 8.9 and 98.3 ± 7.9 compressions/min ( p < 0.001) for the flat floor, hard-, medium-, and soft-firmness mattresses, respectively. Moreover, there was no a significant difference in chest recoil accuracy.

Conclusion:

Using a home-bed mattress did not decrease the chest compression quality, except chest compression rate of soft-firmness mattress. Thus, it may be effective to initiate chest compression on a home-bed mattress if the bystander cannot move the patient to the floor.

In a bed or on the floor? - The effect of realistic hospital resuscitation training: A randomised controlled trial

INTRODUCTION

In-hospital cardiac arrest has a poor prognosis and often occurs in patients lying in a hospital bed. A bed mattress is a soft compressible surface that may decrease cardiopulmonary resuscitation (CPR) quality. Often hospital CPR training is performed with a manikin on the floor.

AIM

To study CPR quality following realistic CPR training with a manikin in a bed compared with one on the floor.

METHODS

We conducted a randomised controlled study. Healthcare professionals were randomised to CPR training with a manikin in a hospital bed or one on the floor. Data on CPR quality was collected from manikins. The primary outcome measure was chest compression depth.

RESULTS

In total, 108 healthcare professionals (age: 40years, female: 94%) were included. The mean chest compression depth was 39mm (standard deviation (SD): 10), for the bed group compared with 38mm (SD: 9) for the floor group, p=0.49. A post hoc analysis showed that regardless of the training method, the participants who optimised their working position by jumping onto the bed or lowering the bed had a median chest compression depth of 39mm (25th-75th percentiles: 33-45) compared with 29mm (25th-75th percentiles: 23-41) for participants who did neither, p=0.04.

CONCLUSION

There was no significant difference in chest compression depth between healthcare professionals who trained CPR on a manikin in a hospital bed compared with one on the floor. Chest compression depth was too shallow in both groups. Irrespective of the training method, participants who optimised their working position performed deeper chest compressions.

Performance of different support surfaces during experimental resuscitation (CPR)

The relationship between the efficacy of resuscitation and the mattresses and backboards used in acute care units, has been studied previously. However, few reports focus on the relative efficacy of resuscitation when using mattresses with different modes of function. This study examines the performance of different support surfaces during experimental cardiopulmonary resuscitation (CPR). The surfaces included a hard surface, a higher specification foam mattress, a dynamic, alternating pressure mattress, and a dynamic, reactive minimum pressure air mattress system. A pressure sensitive mat was placed between the mattresses and each surface and the efficacy of resuscitation measured using differences in compression frequency, compression depth and hands-on time. Our results suggest that the efficacy of resuscitation is dependent on the mode of action of the mattress, while adequate compression frequency and depth do not have a significant effect. In the open system alternating mattress, deflation of the mattress using the CPR function improved the stability of the resuscitation in our study, especially in situations where the height of the air mattress is greater than 20–25 centimeters. Using our experimental system, resuscitation on a closed air system mattress optimally combined stability and effort, while the CPR function converts the air system of the mattress to open, which impairs its functionality during resuscitation. These results indicate that resuscitation is dependent of the mode of action of the mattress and whether the mattress-specific CPR function was used or not. However, the interactions are complex and are dependent on the interaction between the body and the mattress, i.e. its immersion and envelopment properties. Furthermore, this study casts doubt on the necessity of the CPR function in air mattresses.

Manual versus Mechanical Chest Compressions on Surfaces of Varying Softness with or without Backboards: A Randomized, Crossover Manikin Study

BACKGROUND

Chest compression quality is decisive for overall outcome after cardiac arrest. Chest compression depth may decrease when cardiopulmonary resuscitation (CPR) is performed on a mattress, and the use of a backboard does not necessarily improve compression depth. Mechanical chest compression devices may overcome this problem.

OBJECTIVES

We sought to investigate the effectiveness of manual chest compressions both with and without a backboard compared to mechanical CPR performed on surfaces of different softness.

METHODS

Twenty-four advanced life support (ALS)-certified rescuers were enrolled. LUCAS2 (Physio-Control, Redmond, WA) delivers 52 ± 2 mm deep chest compressions and active decompressions back to the neutral position (frequency 102 min(-1); duty cycle, 50%). This simulated CPR scenario was performed on a Resusci-Anne manikin (Laerdal, Stavanger, Norway) that was lying on 3 different surfaces: 1) a concrete floor, 2) a firm standard mattress, and 3) a pressure-relieving mattress. Data were recorded by the Laerdal Skill Reporting System.

RESULTS

Manual chest compression with or without a backboard were performed correctly less often than mechanical chest compressions (floor: 33% [interquartile range {IQR}, 27-48%] vs. 90% [IQR, 86-94%], p < 0.001; standard mattress: 32% [IQR, 20-45%] vs. 27% [IQR, 14-46%] vs. 91% [IQR, 51-94%], p < 0.001; and pressure-relieving mattress 29% [IQR, 17-49%] vs. 30% [IQR, 17-52%] vs. 91% [IQR, 87-95%], p < 0.001). The mean compression depth on both mattresses was deeper with mechanical chest compressions (floor: 53 mm [range, 47-57 mm] vs. 56 mm [range, 54-57 mm], p = 0.003; standard mattress: 50 mm [range, 44-55 mm] vs. 51 mm [range, 47-55 mm] vs. 55 mm [range, 54-58 mm], p < 0.001; and pressure-relieving mattress: 49 mm [range, 44-55 mm] vs. 50 mm [range, 44-53 mm] vs. 55 mm [range, 55-56 mm], p < 0.001). In this ∼6-min scenario, the mean hands-off time was ∼15 to 20 s shorter in the manual CPR scenarios.

CONCLUSIONS

In this experimental study, only ∼30% of manual chest compressions were performed correctly compared to ∼90% of mechanical chest compressions, regardless of the underlying surface. Backboard use did not influence the mean compression depth during manual CPR. Chest compressions were deeper with mechanical CPR. The mean hands-off time was shorter with manual CPR.

The most effective rescuer's position for cardiopulmonary resuscitation provided to patients on beds: a randomized, controlled, crossover mannequin study

BACKGROUND

The effectiveness of chest compressions for cardiopulmonary resuscitation (CPR) is affected by the rescuer's position with respect to the patient. In hospitals, chest compressions are typically performed while standing beside the patient, who is placed on a bed.

STUDY OBJECTIVES

To compare the effectiveness of chest compressions, performed on a bed during 2 min of CPR, among three different rescuer positions: standing, on a footstool, or kneeling on the bed.

METHODS

We performed a crossover randomized simulation trial. Participants were recruited from among students in the Department of Paramedics from July to August 2011. Thirty-eight participants were enrolled, and they performed chest compressions on a mannequin for 2 min in each of the three different positions, with a 1-week interval between each position.

RESULTS

The number of adequate compressions (depth > 50 mm) and the mean compression depth were significantly greater in the kneeling and footstool positions than in the standing position, but there was no significant difference between the kneeling and footstool positions. There were no significant differences in the compression rate, the percentage of correctly released compressions, and the percentage of compressions performed using the correct hand position among the three rescuer positions.

CONCLUSION

The mean compression depth and the number of adequate compressions were greater for both the kneeling and footstool positions than for the standing position during 2 min of CPR. We recommend kneeling on a bed or standing on a footstool as the rescuer positions during hospital CPR on a bed.

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.

Use of backboard and deflation improve quality of chest compression when cardiopulmonary resuscitation is performed on a typical air inflated mattress configuration

No study has examined the effectiveness of backboards and air deflation for achieving adequate chest compression (CC) depth on air mattresses with the typical configurations seen in intensive care units. To determine this efficacy, we measured mattress compression depth (MCD, mm) on these surfaces using dual accelerometers. Eight cardiopulmonary resuscitation providers performed CCs on manikins lying on 4 different surfaces using a visual feedback system. The surfaces were as follows: A, a bed frame; B, a deflated air mattress placed on top of a foam mattress laid on a bed frame; C, a typical air mattress configuration with an inflated air mattress placed on a foam mattress laid on a bed frame; and D, C with a backboard. Deflation of the air mattress decreased MCD significantly (B; 14.74 ± 1.36 vs C; 30.16 ± 3.96, P < 0.001). The use of a backboard also decreased MCD (C; 30.16 ± 3.96 vs D; 25.46 ± 2.89, P = 0.002). However, deflation of the air mattress decreased MCD more than use of a backboard (B; 14.74 ± 1.36 vs D; 25.46 ± 2.89, P = 0.002). The use of a both a backboard and a deflated air mattress in this configuration reduces MCD and thus helps achieve accurate CC depth during cardiopulmonary resuscitation.

Muscles used for chest compression under static and transportation conditions

BACKGROUND

Unstable conditions during ambulance transportation are not conducive to the performance of high-quality cardiopulmonary resuscitation by emergency medical technicians.

OBJECTIVE

The present study was conducted to clarify differences in the quality of chest compression and associated muscle activity between static and ambulance transportation conditions.

METHODS

Nine paramedic students performed chest compression for 5 minutes on the floor and during ambulance transportation. Compression rate and depth and success and error rates of chest compression were determined using the Resusci Anne manikin with a PC SkillReporting System (Laerdal Medical). Integrated electromyography (i-EMG) values of eight different muscles were also recorded bilaterally during the first and last 30 seconds of compression.

RESULTS

There was no significant difference in compression rate per minute (p = 0.232) and depth of chest compression (p = 0.174) between the two conditions. The success rate was significantly lower under the ambulance transportation condition than under the static condition (p = 0.0161). Compared with those under the static condition, the total i-EMG values were significantly lower for the multifidus (p = 0.0072) and biceps femoris (p < 0.0001) muscles and significantly higher for the deltoid (p = 0.0032), pectoralis major (p = 0.0037), triceps brachii (p = 0.0014), vastus lateralis (p < 0.0001), and gastrocnemius (p = 0.0004) muscles under the ambulance transportation condition.

CONCLUSIONS

Chest compression is performed mainly through flexion and extension of the hip joint while kneeling on the floor and through the elbow and shoulder joints while standing in a moving ambulance. Therefore, the low quality of chest compression during ambulance transportation may be attributable to an altered technique of performing the procedure.

Backboards are important when chest compressions are provided on a soft mattress

AIM

Determine the impact of backboard placement, torso weight and bed compression on chest compression (CC) depth feedback in simulated cardiac arrest patients.

METHODS

Epochs of 50 high quality CCs with real-time feedback of sternum-to-spine compression depth were provided by a blinded BLS/ACLS/PALS certified provider on manikins of two torso weights (25 vs. 50 kg), using three bed surfaces (stretcher, Stryker hospital bed with Impression mattress, soft Total Care ICU bed), with/without a backboard (BB). Two BB sizes were tested (small: 60 cm × 50 cm; large: 89 cm × 50 cm) in vertical vs. horizontal orientation. Mattress displacement was measured using an accelerometer placed internally on the spine plate of the manikin. Mattress displacement of ≥ 5 mm was prospectively defined as the minimal clinically important difference.

RESULTS

During CPR (CC depth: 51.8 ± 2.8mm), BB use significantly reduced mattress displacement only for soft ICU beds. Mattress displacement was reduced (vs. no BB) for 25 kg torso weight: small BB12.3mm (95%CI 11.9-12.6), horizontally oriented large BB 11.2mm (95%CI 10.8-11.7), and vertically oriented large BB 12.2mm (95%CI 11.8-12.6), and for 50 kg torso weight: small BB 7.4mm (95%CI 7.1-7.8), horizontally oriented large BB 7.9 mm (95%CI 7.6-8.3), and vertically oriented large BB 6.2mm (95%CI 5.8-6.5; all p<0.001). BB size and orientation did not significantly affect mattress displacement. Lighter torso weight was associated with larger displacement in soft ICU beds without BB (difference: 6.9 mm, p<0.001).

CONCLUSION

BB is important for CPR when performed on soft surfaces, such as ICU beds, especially when torso weight is light. BB may not be needed on stretchers, relatively firm hospital beds, or for patients with heavy torso weights.

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.

Effect of feedback on delaying deterioration in quality of compressions during 2 minutes of continuous chest compressions: a randomized manikin study investigating performance with and without feedback

Background

Good quality basic life support (BLS) improves outcome following cardiac arrest. As BLS performance deteriorates over time we performed a parallel group, superiority study to investigate the effect of feedback on quality of chest compression with the hypothesis that feedback delays deterioration of quality of compressions.

Methods

Participants attending a national one-day conference on cardiac arrest and CPR in Denmark were randomized to perform single-rescuer BLS with (n = 26) or without verbal and visual feedback (n = 28) on a manikin using a ZOLL AED plus. Data were analyzed using Rescuenet Code Review. Blinding of participants was not possible, but allocation concealment was performed. Primary outcome was the proportion of delivered compressions within target depth compared over a 2-minute period within the groups and between the groups. Secondary outcome was the proportion of delivered compressions within target rate compared over a 2-minute period within the groups and between the groups. Performance variables for 30-second intervals were analyzed and compared.

Results

24 (92%) and 23 (82%) had CPR experience in the group with and without feedback respectively. 14 (54%) were CPR instructors in the feedback group and 18 (64%) in the group without feedback. Data from 26 and 28 participants were analyzed respectively. Although median values for proportion of delivered compressions within target depth were higher in the feedback group (0-30 s: 54.0%; 30-60 s: 88.0%; 60-90 s: 72.6%; 90-120 s: 87.0%), no significant difference was found when compared to without feedback (0-30 s: 19.6%; 30-60 s: 33.1%; 60-90 s: 44.5%; 90-120 s: 32.7%) and no significant deteriorations over time were found within the groups. In the feedback group a significant improvement was found in the proportion of delivered compressions below target depth when the subsequent intervals were compared to the first 30 seconds (0-30 s: 3.9%; 30-60 s: 0.0%; 60-90 s: 0.0%; 90-120 s: 0.0%). Significant differences were not found in secondary outcome and in other performance variables between the groups and over time

Conclusions

Quality of CPR was maintained during 2 minutes of continuous compressions regardless of feedback in a group of trained rescuers.

The use of dual accelerometers improves measurement of chest compression depth

BACKGROUND

Chest compression (CC) feedback devices are used to perform CC measurements effectively and accurately on patients in hospital beds. However, these devices do not take account of the compression of the mattress, which results in overestimation of CC depth. In this study, we propose a new method using two accelerometers to overcome this limitation and thus measure compression depth more accurately when performing cardiopulmonary resuscitation (CPR) on patients.

METHOD

One accelerometer was placed on the manikin's sternum (a1), and the other between the manikin's back and the mattress (a2). The compression depth was calculated by integrating the acceleration twice using a digital signal processing technique. We compared CC depth from dual accelerometers and single accelerometer (a1) on the foam and inflated air mattress with eight CPR providers.

RESULT

When CC was done on a manikin lying on the floor, there was no significant difference between measurement techniques (p>0.05). When CC was done on a manikin lying on the foam and inflated air mattress supporting system, our method significantly improved the estimation of CC depth, irrespective of the presence or absence of a backboard (p<0.001).

CONCLUSION

Measuring CC depth using two accelerometers is more effective than using one in increasing the accuracy of CC depth estimation when CPR is performed on the foam and inflated air mattress, regardless of the presence or absence of a backboard.

Decay in chest compression quality due to fatigue is rare during prolonged advanced life support in a manikin model

BACKGROUND

The aim of this study was to measure chest compression decay during simulated advanced life support (ALS) in a cardiac arrest manikin model.

METHODS

19 paramedic teams, each consisting of three paramedics, performed ALS for 12 minutes with the same paramedic providing all chest compressions. The patient was a resuscitation manikin found in ventricular fibrillation (VF). The first shock terminated the VF and the patient remained in pulseless electrical activity (PEA) throughout the scenario. Average chest compression depth and rate was measured each minute for 12 minutes and divided into three groups based on chest compression quality; good (compression depth ≥ 40 mm, compression rate 100-120/minute for each minute of CPR), bad (initial compression depth < 40 mm, initial compression rate < 100 or > 120/minute) or decay (change from good to bad during the 12 minutes). Changes in no-flow ratio (NFR, defined as the time without chest compressions divided by the total time of the ALS scenario) over time was also measured.

RESULTS

Based on compression depth, 5 (26%), 9 (47%) and 5 (26%) were good, bad and with decay, respectively. Only one paramedic experienced decay within the first two minutes. Based on compression rate, 6 (32%), 6 (32%) and 7 (37%) were good, bad and with decay, respectively. NFR was 22% in both the 1-3 and 4-6 minute periods, respectively, but decreased to 14% in the 7-9 minute period (P = 0.002) and to 10% in the 10-12 minute period (P < 0.001).

CONCLUSIONS

In this simulated cardiac arrest manikin study, only half of the providers achieved guideline recommended compression depth during prolonged ALS. Large inter-individual differences in chest compression quality were already present from the initiation of CPR. Chest compression decay and thereby fatigue within the first two minutes was rare.