Adequate Chest Compression Research Articles

Abstract 11888: Mechanical Circulatory Support Increases Return of Spontaneous Circulation in Patients Receiving Mechanical Chest Compressions for Cardiac Arrest in the Cardiac Catheterization Laboratory

Introduction: In the cardiac catheterization laboratory (CCL), use of a mechanical chest compression (MCC) device allows acute cardiac life support (ACLS) and percutaneous interventions to occur simultaneously. Use of MCC in the CCL ensures adequate chest compressions without relying on manual compression providers. This is especially important in the context of recent studies that have shown that therapies offered in the CCL increase survival in patients with cardiac arrest. Furthermore, mechanical circulatory support (MCS) has been shown to improve outcomes of patients with cardiac arrest, but it is not known whether emergent, percutaneous MCS initiation provides clinical efficacy in patients undergoing MCC-assisted ACLS in the CCL. Methods: We performed a retrospective analysis of patients who received MCC-assisted ACLS in the CCL at our institution between April 2014 and February 2016. Baseline characteristics, resuscitation characteristics, and clinical outcomes were compared between patients who were treated with MCS and those who were not. Unpaired two-sample t-tests were used to compare continuous variables. Fisher’s exact test was used to compare categorical variables. Results: Thirty-one patients received MCC-assisted ACLS in the CCL. Twenty-two patients (71%) were treated with MCS (14 external cardiac life support (ECLS), 3 Impella, 5 intra-aortic balloon pump (IABP)). Patients who received MCS were significantly more likely to achieve return of spontaneous circulation (ROSC) than those who did not receive MCS (95% v 22%, p = 0.00). Thirty-day survival was more common in the group receiving MCS (Table 1). The majority of patients who received MCS suffered cardiac arrest either outside the hospital or in the emergency department. Conclusions: The addition of percutaneous MCS to MCC-assisted ACLS increased the rate of ROSC. These findings support the use of emergent percutaneous MCS during MCC-assisted ACLS in the CCL.

337 CPR in Whitewater Drowning Victims: Is it Possible to Perform Adequate Chest Compressions Through a Personal Flotation Device?

337 CPR in Whitewater Drowning Victims: Is it Possible to Perform Adequate Chest Compressions Through a Personal Flotation Device?

Chest compressions performance of emergency medical technicians in Japan before and after 2015 CoSTR statement

Background: Adequate chest compression (CC) depth is critical for effective cardiopulmonary resuscitation (CPR). Although previous recommendations regarding compression depth have been at least 5 cm, the statement of Consensus on Science and Treatment Recommendations (CoSTR) 2015 proposed a lower threshold of 5 cm and an upper threshold of chest compression of 6 cm. Adherence to both upper and lower thresholds is challenging.

CPR in Whitewater Drowning Victims: Is It Possible To Perform Adequate Chest Compressions Through a Personal Flotation Device (PFD)?

CPR in Whitewater Drowning Victims: Is It Possible To Perform Adequate Chest Compressions Through a Personal Flotation Device (PFD)?

Remember fatigue during neonatal cardiopulmonary resuscitation and don't forget to change resuscitators

The majority of newborn infants successfully make the transition from foetal to neonatal life without any help 1. However, an estimated 10% of newborns need help to establish effective ventilation, which remains the most critical step of neonatal resuscitation. Fortunately, the need for chest compression (CC) or medications in the delivery room (DR) is rare. Approximately 0.8% term neonates and up to 10% of preterm neonates require CC at birth 1, 2. In term infants, these interventions result in approximately 1 million newborn deaths annually worldwide 3. The current resuscitation techniques, which are revised by the International Liaison Committee On Resuscitation (ILCOR) every 5 years, are based on current understanding and latest evidence 4. If a newborn infants needs chest compression, ILCOR recommends to deliver a CC to ventilation (C:V) ratio of 3 CC and 1 ventilation (3:1 C:V ratio) 4. The recommendation of a ratio of 3:1 C:V is based on expert opinion and consensus rather than strong scientific evidence. Rationales for using a 3:1 C:V ratio include the higher physiological heart rate of 120–160/min and breathing rates of 40–60/min in newborns compared with adults. Furthermore, profound bradycardia or cardiac arrest in newborns is usually caused by hypoxia rather than primary cardiac compromise; therefore, providing ventilation is more likely to be beneficial in neonatal CPR compared with adult CPR 1. Successful resuscitation requires the delivery of high-quality CC, encompassing several factors including (A) optimal C:V ratio, (B) adequate rate, (C) depth of CC and (D) full recoil between compressions 3. Although there is an agreement that these factors are all important for a successful resuscitation, neither has been extensively studied to optimise coronary and cerebral perfusion while providing adequate ventilation of an asphyxiated newborn. In this issue of Acta paediatrica, Boldingh et al. 5 examined two of these important factors (factors A and C) in a manikin model. Factor A: Current neonatal resuscitation guidelines recommend 3:1 C:V ratio; however, the most effective C:V ratio in newborns remains controversial. Unfortunately, during clinical observation not even experienced resuscitators do always comply with the current algorithm of neonatal CPR 6. These observations are further supported by manikin studies that participants did not manage to deliver the intended number of ventilations during CPR at the 3:1 C:V ratio 7. In particular, compliance with the current algorithm is poor in simulated neonatal CPR with providers, irrespective of experience, performing CC at a significantly higher rate than the recommended 90 CC per minute 8. In the current study, Boldingh et al. reported similar observations, although the CC and ventilation were within the target range and CC rate and number of CC/min were below the target 5. These deviations from the current suggested 3:1 C:V ratio might be attributed to increased stress level during these situations and that this deviation from the guidelines is not exceptional. Current neonatal resuscitation guidelines recommend an external CC depth of ~33% of the anterior–posterior (AP) chest diameter 4. In addition, there is a positive correlation between receiving adequate CC and improved outcomes (e.g. to achieve adequate cardiac output) 9. In contrary, over-compressing of the chest will result in inadequate residual chest depth during CPR and could lead to rib fractures, cardiac contusion and other thoracic injuries. Despite the importance of delivering appropriate CC, adequate CC AP depth has not been rigorously evaluated in neonates. Further, CC depth should be tailored to produce a palpable pulse and sufficient diastolic blood pressure during CPR. A recent computer tomography study reported the AP diameter to be 90 mm in newborn infants 10. This would suggest that CC depth should be ~30 mm. Boldingh et al. reported a similar depth in their current study. Participants had higher and more consistent CC depth during 3:1 C:V CPR, and the depth decay during CC was significantly higher during continuous CC with asynchronised ventilation 5. Similar results have been reported form several other manikin studies 11, 12. Overall using a 3:1 C:V ratio compared with continuous CC with asynchronised ventilation seems to allow some fatigue recovery. However, the current study by Boldingh et al. in addition to the already published studies strongly suggests that during neonatal resuscitation, operators should change every 2–3 minutes to avoid fatigue, which could lead to a lower AP diameter during CC. This potentially could cause increased mortality. Overall, the study by Boldingh et al. supports the currently recommended 3:1 C:V ratio. However, more studies are needed to investigate different chest compression ratios to optimise neonatal resuscitation. Dr. Schmölzer is a recipient of the Heart and Stroke Foundation/University of Alberta Professorship of Neonatal Resuscitation and a Heart and Stroke Scholarship.

Muscular fitness as a mediator of quality cardiopulmonary resuscitation

BackgroundIt has been hypothesized that body mass index (BMI) and muscle strength (MS) of the rescuers are predictors of adequate external chest compressions (ECC). The aims of this study were: (a) to analyze, in college students, the relationship between BMI and MS with adequate ECC parameters; and (b) to examine whether the association between BMI and adequate ECC parameters is mediated by MS. MethodsA cross-sectional analysis of the evaluation of a CPR performance test involving students (n=63). We determined BMI and MS. After previous training, participants performed cardiopulmonary resuscitation on a mannequin for 20 minutes. PROCESS macro developed by Preacher and Hayes was used to assess whether the association between BMI and ECC was mediated by MS. ResultsUnderweight subjects achieved lower results than those with normal weight and overweight/obese in several dependent variables including: correct compression depth (P<.001) and adequate ECC (P<.001). This differences remained after adjusting for muscle strength except for the compression rate (P=.053). Moreover, participants in the low MS quartile were lower in both correct compression depth (P=.001) and adequate ECC (P<.001) than participants in the medium/high quartile after adjusting for confounding variables. The effect of BMI on adequate ECC was partially mediated by MS. Similar results were obtained in the analysis of the mediator role of MS in the relationship between BMI and correct compression depth. ConclusionsThe ability to provide adequate ECC is influenced by the rescuer's MS. Rescuers should be advised to exercise arm strength to improve the quality of CPR.

Proper target depth of an accelerometer-based feedback device during CPR performed on a hospital bed: a randomized simulation study

PurposeFeedback devices are used to improve chest compression (CC) quality related to survival rates in cardiac arrest. However, several studies have shown that feedback devices are not sufficiently reliable to ensure adequate CC depth on soft surfaces. Here, we determined the proper target depth of feedback (TDF) using an accelerometer during cardiopulmonary resuscitation in hospital beds. MethodsIn prospective randomized crossover study, 19 emergency physicians performed CCs for 2 minutes continuously on a manikin in 2 different beds with 3 TDFs (5, 6, and 7 cm). We measured CC depth, the proportion of accurate compression depths, CC rate, the proportion of incomplete chest decompressions, the velocity of CC (CC velocity), the proportion of time spent in CC relative to compression plus decompression (duty cycle), and the time spent in CC (CC time). ResultsMean (SD) CC depths at TDF 5, 6, and 7 were 45.42 (5.79), 52.68 (4.18), and 58.47 (2.48) on one bed and 46.26 (4.49), 53.58 (3.15), and 58.74 (2.10) mm on the other bed (all P < .001), respectively. The proportions of accurate compression depths and CC velocity at TDF 5, 6, and 7 differed significantly according to TDF on both beds (all P < .001).The CC rate, CC time, and proportion of incomplete chest decompression did not differ on both beds (all P > .05). The duty cycle differed significantly on only B2. ConclusionsThe target depth of the real-time feedback device should be at least 6 cm but should not exceed 7 cm for optimal CC on patients on hospital beds.

Mechanical chest compression: an alternative in helicopter emergency medical services?

Mechanical chest compression devices are mentioned in the current guidelines of the European Resuscitation Council (ERC) as an alternative in long-lasting cardiopulmonary resuscitations (CPR) or during transport with ongoing CPR. We compared manual chest compression with mechanical devices in a rescue-helicopter-based scenario using a resuscitation manikin. Manual chest compression was compared with the mechanical devices LUCAS™ 2, AutoPulse™ and animax mono (10 series each) using the resuscitation manikin AmbuMan MegaCode Wireless, which was intubated endotracheally and controlled ventilated during the entire scenario. The scenario comprised the installation of each device, transport and loading phases, as well as a 10-min phase inside the helicopter (type BK 117). We investigated practicability as well as measured compression quality. All mechanical devices could be used readily in a BK 117 helicopter. The LUCAS 2 group was the only one that fulfilled all recommendations of the ERC (frequency 102 ± 0.1 min(-1), compression depth 54 ± 3 mm, hands-off time 2.5 ± 1.6 %). Performing adequate manual chest compression was barely possible (fraction of correct compressions 21 ± 15 %). In all four groups, the total hands-off time was <10 %. Performing manual chest compressions during rescue-helicopter transport is barely possible, and only of poor quality. If rescuers are experienced, mechanical chest compression devices could be good alternatives in this situation. We found that the LUCAS 2 system complied with all recommendations of ERC guidelines, and all three tested devices worked consistently during the entire scenario.

Magical manoeuvre: a 5-second instructor's intervention helps lightweight female rescuers achieve the required chest compression depth

Adequate chest compression (CC) depth is crucial for resuscitation outcomes. Lightweight rescuers, particularly women, are often unable to achieve the required 5 to 6 cm CC depth. This nonrandomised cohort study investigated new strategies to improve CC performance.

Effectiveness and feasibility of assistant push on improvement of chest compression quality: a crossover study

PurposeTo improve the quality of chest compression (CC), we developed the assistant-push method, whereby the second rescuer pushes the back of the chest compressor during CC. We investigated the effectiveness and feasibility of assistant push in achieving and maintaining the CC quality. MethodsThis was a randomized crossover trial in which 41 subjects randomly performed both of standard CC (single-rescuer group) and CC with instructor-driven assistant push (assistant-push group) in different order. Each session of CC was performed for 2 minutes using a manikin. Subjects were also assigned to both roles of chest compressor and assistant and together performed CC with subject-driven assistant push. Depth of CC, compression to recoil ratio, duty cycle, and rate of incomplete recoil were quantified. ResultsThe mean depth of CC (57.0 [56.0-59.0] vs 55.0 [49.5-57.5], P < .001) was significantly deeper, and the compression force (33.8 [29.3-36.4] vs 23.3 [20.4-25.3], P < .001) was stronger in the assistant-push group. The ratio of compression to recoil, duty cycle, and rate of incomplete chest recoil were comparable between the 2 groups. The CC depth in the single-rescuer group decreased significantly every 30 seconds, whereas in the assistant-push group, it was comparable at 60- and 90-second time points (P = .004). The subject assistant-push group performed CCs at a depth comparable with that of the instructor assistant-push group. ConclusionThe assistant-push method improved the depth of CC and attenuated its decline, eventually helping maintain adequate CC depth over time. Subjects were able to feasibly learn assistant push and performed effectively.

Perception of CPR quality: Influence of CPR feedback, Just-in-Time CPR training and provider role

AimMany healthcare providers rely on visual perception to guide cardiopulmonary resuscitation (CPR), but little is known about the accuracy of provider perceptions of CPR quality. We aimed to describe the difference between perceived versus measured CPR quality, and to determine the impact of provider role, real-time visual CPR feedback and Just-in-Time (JIT) CPR training on provider perceptions. MethodsWe conducted secondary analyses of data collected from a prospective, multicenter, randomized trial of 324 healthcare providers who participated in a simulated cardiac arrest scenario between July 2012 and April 2014. Participants were randomized to one of four permutations of: JIT CPR training and real-time visual CPR feedback. We calculated the difference between perceived and measured quality of CPR and reported the proportion of subjects accurately estimating the quality of CPR within each study arm. ResultsParticipants overestimated achieving adequate chest compression depth (mean difference range: 16.1–60.6%) and rate (range: 0.2–51%), and underestimated chest compression fraction (0.2–2.9%) across all arms. Compared to no intervention, the use of real-time feedback and JIT CPR training (alone or in combination) improved perception of depth (p<0.001). Accurate estimation of CPR quality was poor for chest compression depth (0–13%), rate (5–46%) and chest compression fraction (60–63%). Perception of depth is more accurate in CPR providers versus team leaders (27.8% vs. 7.4%; p=0.043) when using real-time feedback. ConclusionHealthcare providers’ visual perception of CPR quality is poor. Perceptions of CPR depth are improved by using real-time visual feedback and with prior JIT CPR training.

Magical manoeuvre

BackgroundAdequate chest compression (CC) depth is crucial for resuscitation outcomes. Lightweight rescuers, particularly women, are often unable to achieve the required 5–6 cm CC depth. This nonrandomized cohort study investigated new strategies to improve CC performance.ObjectiveTo evaluate the effects of a 5-s instructor’s intervention on the depth of CCs performed by female rescuers during standard video self-instruction basic life support training.MethodsData were prospectively collected from January 2011 to January 2012 from 336 female medical and pharmacy students undergoing cardiopulmonary resuscitation (CPR) training at the Lithuanian University of Health Sciences. During the training process, the instructors performed a simple 5-s intervention (Andrew’s manoeuvre) with all of the rescuers in the study group. The instructor pushed 10 times on the shoulders of each trainee while she performed CCs to achieve the maximal required compression depth. Immediately after training, the participants were asked to perform a 6-min basic life support test on a manikin that was connected to a PC with Skill Reporter System software; the quality of the participants’ CPR skills was then evaluated.ResultsThe CC depth in the study group increased by 6.4 mm (P<0.001) compared with the control group (52.9 vs. 46.6 mm). A regression analysis showed that Andrew’s manoeuvre increased the depth of the CCs among women by 14.87×(1−0.01×weight) mm.ConclusionA simple 5-s instructor’s intervention during the CPR training significantly improved the performance of the female rescuers and helped them achieve the CC depth required by 2010 resuscitation guidelines. Andrew’s manoeuvre is most effective among the women with the lowest body weight.

Comparison of CPR quality and rescuer fatigue between standard 30:2 CPR and chest compression-only CPR: a randomized crossover manikin trial.

ObjectiveWe aimed to compare rescuer fatigue and cardiopulmonary resuscitation (CPR) quality between standard 30:2 CPR (ST-CPR) and chest compression only CPR (CO-CPR) performed for 8 minutes on a realistic manikin by following the 2010 CPR guidelines.MethodsAll 36 volunteers (laypersons; 18 men and 18 women) were randomized to ST-CPR or CO-CPR at first, and then each CPR technique was performed for 8 minutes with a 3-hour rest interval. We measured the mean blood pressure (MBP) of the volunteers before and after performing each CPR technique, and continuously monitored the heart rate (HR) of the volunteers during each CPR technique using the MRx monitor. CPR quality measures included the depth of chest compression (CC) and the number of adequate CCs per minute.ResultsThe adequate CC rate significantly differed between the 2 groups after 2 minutes, with it being higher in the ST-CPR group than in the CO-CPR group. Additionally, the adequate CC rate significantly differed between the 2 groups during 8 minutes for male volunteers (p =0.012). The number of adequate CCs was higher in the ST-CPR group than in the CO-CPR group after 3 minutes (p =0.001). The change in MBP before and after performing CPR did not differ between the 2 groups. However, the change in HR during 8 minutes of CPR was higher in the CO-CPR group than in the ST-CPR group (p =0.007).ConclusionsThe rate and number of adequate CCs were significantly lower with the CO-CPR than with the ST-CPR after 2 and 6 minutes, respectively, and performer fatigue was higher with the CO-CPR than with the ST-CPR during 8 minutes of CPR.

A Randomised, Cross over Study Using a Mannequin Model to Evaluate the Effects on CPR Quality of Real-Time Audio-Visual Feedback Provided by a Smartphone Application

Objective To evaluate the effect of real time feedback provided by smartphone application on cardiopulmonary resuscitation (CPR) performance. Methods Participants were randomised in two groups based on whether chest compression with or without the assistance of the smartphone application. Both groups performed hands-only CPR on a mannequin for 4 minutes. Data on CPR performance of both groups was compared. To assess the reliability the feedback value, we compared the CPR data from Skillmeter and data from smartphone. A questionnaire survey to participants about the usefulness of the application was also evaluated. Results Twenty-one subjects were recruited for the study. We found no significant difference in mean chest compression rate (103.3±5.0/min vs. 107.1±1.7/min; p=0.133) and depth between the two groups (47.3 [39.3, 56.2] mm vs. 45.8 [40.3, 49.9] mm; p=0.085). The proportion of adequate compression depth over the total compression was significantly higher in the group using the smartphone (38.1% vs. 22.2%; p=0.034). The CPR data displayed on smartphone application in mannequin's chest was not different from Skillmeter software. The majority of the participants considered the application easy to use, but holding the smartphone during CPR hampered compression. Conclusions Real-time audio-visual feedback on CPR depth and rate using a smartphone application can help to maintain the adequate chest compression depth in prolonged CPR. A better method to hold the smartphone may maximise the feedback effect on CPR quality. (Hong Kong j.emerg.med. 2014;21:153-160)

The effect of inclined step stool on the quality of chest compression during in-hospital cardiopulmonary resuscitation

PurposeA step stool is an ordinary device to improve the quality of chest compression (CC) during in-hospital cardiopulmonary resuscitation (CPR). We investigated the effect of an inclined step stool on the quality of CC during CPR on a hospital bed. MethodsWe conducted a randomized crossover study of simulation using a manikin. Two different methods of CC were performed and compared: CC using a flat stool and CC using an inclined (20°) stool. Each session of CC was performed for 2 minutes using a metronome at a rate of 110 beats per minute. The primary outcome was the depth of CC. The adequate CC rate, duty cycle, rate of incomplete recoil, and the angle between the arm of the participants and the bed were also measured. ResultsThe median value of the mean depth of CC was 50.5 mm (45.0-57.0 mm) in the flat stool group and 54.5 mm (47.0-58.3 mm) in the inclined stool group (P = .014). The adequate CC rate was significantly higher in the inclined stool group (84.2% [37.6%-99.1%] vs 57.0% [15.2%-95.0%]; P = .016). The duty cycle and the rate of incomplete recoil were comparable between the 2 groups. The angles between the arm of the participants and the bed were more vertical in the inclined stool group (84.0° ± 5.2° vs 81.0° ± 4.8°; P = .014). ConclusionUsing an inclined stool resulted in an improvement in the depth of CC and the adequate CC rate without increasing the rate of incomplete chest recoil.

Video analysis of cardiopulmonary resuscitation performance of ambulance crews during transportation

High quality of chest compressions during cardiopulmonary resuscitation (CPR) is a critical determinant of outcome from out-of-hospital cardiac arrest (OHCA). Unfortunately, however, victims often do not receive adequate chest compression for various reasons, particularly during transportation. Recent studies have demonstrated the interruption time of chest compression using transthoracic impedance analysis, but more information is needed to evaluate the performance of CPR provided by ambulance crews and reveal reasons for hands off chest during CPR.

Improvement in chest compression quality using a feedback device (CPRmeter): a simulation randomized crossover study

PurposesCardiac arrest survival depends on celerity and efficiency of life support action. Guidelines emphasized the chest compression (CC) quality and feedback devices are encouraged. The purpose is to study the impact of the CPRmeter feedback device on resuscitation performed by untrained rescuers. Basic proceduresThis is a prospective randomized crossover study on manikins (Resusci Anne). One hundred and forty four students inexperienced in cardiopulmonary resuscitation representing untrained rescuers were included. Participants performed 2 minutes of CC without interruption with (group G) or without (group B) feedback. Four months passed between the 2 crossover phases to avoid resilience effect. Data collected by the CPRmeter device were: CC rate, depth and release. Main findingsEfficient CC rate ([simultaneous and correct CC rate, depth and release] primary outcome) (absolute difference [95% CI]) was significantly improved in group G (71%) compared to group B (26%; [45 {36-55}]; P < .0001). Adequate depth rate (>38 mm) was significantly improved in group G (85%) compared to group B (43%; [42 {33-52}]; P < .0001). Adequate CC rate (90-120/min) was significantly improved in group G (81%) compared to group B (56%; [25 {15-35}]; P < .0001). The average CC rate and depth in group G were significantly less dispersed around the mean compared to group B (test of variance P < .007; P < .015 respectively). Principal conclusionsThe use of the CPRmeter significantly improved CC quality performed by students inexperienced in cardiopulmonary resuscitation.

Does the quality of chest compressions deteriorate when the chest compression rate is above 120/min?

ObjectivesThe quality of chest compressions along with defibrillation is the cornerstone of cardiopulmonary resuscitation (CPR), which is known to improve the outcome of cardiac arrest. We aimed to investigate the...

Decline in Adequate Chest Compressions Is Similar in Children and Adults

The American Heart Association defines effective chest compression during cardiopulmonary resuscitation (CPR) as >100 compressions per minute at a depth >38 mm. In a prospective randomized crossover study, investigators compared quality of compressions and the work required to perform them on a 5-year old manikin and an adult …

Evaluation of Chest Compression Depth during Nine Minutes of Hands-Only Cardiopulmonary Resuscitation Performed by a Lone Rescuer and its Effect by Age Group: A Pilot Simulation Study Using a Manikin

Objective There have been few studies on the use of long-standing hands-only cardiopulmonary resuscitation (CPR) by a lone rescuer. This study aimed to evaluate the long-standing (nine minutes) hands-only CPR by a lone rescuer, and the change of chest compression depth over time. The effect of age of rescuer on chest compression depth was also studied. Methods From a total of 404 adult lay-persons who participated in CPR training, 91 subjects were enrolled in the simulation trial of nine minutes of hands-only CPR using a manikin with a Skill-Reporter™. The quality of the chest compression over time and the effects of rescuer age were analysed. Results Of the 91 participants, 74 (81%) fully completed the nine minutes of CPR. No significant differences of incomplete CPR rate between each age group were observed. No significant differences in the degree of reduction in effective chest compressions were observed based on the time course among the different age groups. The total number of compressions decreased abruptly from the six-minute time point onwards (five minutes vs. six minutes, p=0.038). Conclusions Most trained lay-persons could complete the 9 minutes of hands-only CPR. The rate of chest compression shows a significant decrease after 6 minute. We do not find a significant difference in the decrease of adequate chest compressions over time among various age groups in this pilot simulation study.