Average Chest Compression Depth Research Articles

Design and Evaluation of CPR Emergency Equipment for Non-Professionals.

Sudden cardiac death is a sudden and highly fatal condition. Implementing high-quality emergency cardiopulmonary resuscitation (CPR) early on is an effective rescue method for this disease. However, the rescue steps of CPR are complicated and difficult to remember, and the quantitative indicators are difficult to control, which leads to a poor quality of CPR emergency actions outside the hospital setting. Therefore, we have developed CPR emergency equipment with a multisensory feedback function, aiming to guide rescuers in performing CPR through visual, auditory, and tactile interaction. This equipment consists of three components: first aid clothing, an audio-visual integrated terminal, and a vital sign detector. These three components are based on a micro-power WiFi-Mesh network, enabling the long-term wireless transmission of the multisensor data. To evaluate the impact of the multisensory feedback CPR emergency equipment on nonprofessionals, we conducted a controlled experiment involving 32 nonmedical subjects. Each subject was assigned to either the experimental group, which used the equipment, or the control group, which did not. The main evaluation criteria were the chest compression (CC) depth, the CC rate, the precise depth of the CC ratio (5-6 cm), and the precise rate of the CC ratio -(100-120 times/min). The results indicated that the average CC depth in the experimental group was 51.5 ± 1.3 mm, which was significantly better than that of the control group (50.2 ± 2.2 mm, p = 0.012). Moreover, the average CC rate in the experimental group (110.1 ± 6.2 times/min) was significantly higher than that of the control group (100.4 ± 6.6 times/min) (p < 0.001). Compared to the control group (66.37%), the experimental group showed a higher proportion of precise CC depth (82.11%), which is closer to the standard CPR rate of 100%. In addition, the CC ratio of the precise rate was 93.75% in the experimental group, which was significantly better than that of 56.52% in the control group (p = 0.024). Following the experiment, the revised System Availability Scale (SUS) was utilized to evaluate the equipment's usability. The average total SUS score was 78.594, indicating that the equipment's acceptability range was evaluated as 'acceptable', and the overall adjective rating was 'good'. In conclusion, the multisensory feedback CPR emergency equipment significantly enhances the CC performance (CC depth, CC rate, the precise depth of CC ratio, the precise rate of CC ratio) of nonprofessionals during CPR, and the majority of participants perceive the equipment as being easy to use.

Effects of resuscitation guideline terminology on pediatric cardiopulmonary resuscitation

This study aimed to investigate the effect of resuscitation guideline terminology on pediatric cardiopulmonary resuscitation (CPR) performance. This was a prospective randomised crossover simulation trial. A total of 32 medical doctors conducted 2-min single-rescuer CPR using the one-handed chest compression technique (OHCC) or two-handed chest compression technique (THCC) on a pediatric manikin. The participants conducted chest compressions according to the chest compression depth (CCD) target of '5 cm (Test 1)' or 'at least one third of the anterior-posterior dimension of the chest (Test 2)' in a random order. In both techniques (OHCC or THCC), the average CCD of Test 1 were significantly lower than those of Test 2 (OHCC: 50.0 mm [46.0-52.0 mm] in Test 1 vs. 52.0 mm [50.3-55.0 mm] in Test 2, P = 0.001; THCC: 52.0 mm [50.3-55.0 mm] in Test 1 vs. 58.0 mm [54.0-62.0 mm] in Test 2, P < 0.001). The adequacy of the chest compressions was also superior in Test 2 (OHCC: 63.0% [7.5-95.8%] in Test 1 vs. 96.5% [78.8-99.9%] in Test 2, P < 0.001; THCC: 96.5% [78.8-99.9%] in Test 1 vs. 100.0% [100.0-100.0%] in Test 2, P < 0.001). Ventilation parameters were not significantly different between Tests 1 and 2. Average CCD during simulated pediatric CPR according to the CCD target of '5 cm' was significantly lower than those according to the CCD target of 'at least one third of the anterior-posterior dimension of the chest'.

Long-term benefits of chest compression-only cardiopulmonary resuscitation training using real-time visual feedback manikins: a randomized simulation study.

ObjectiveCardiopulmonary resuscitation (CPR) education with a feedback device is known to result in better CPR skills compared to one without the feedback device. However, its long-term benefits have not been established. The purpose of this study was to evaluate the long-term CPR skill retention after training using real-time visual manikins in comparison to that of non-feedback manikins.MethodsWe recruited 120 general university students who were randomly divided into the real-time feedback group (RTFG) and the non-feedback group. Of them, 95 (RTFG, 48; non-feedback group, 47) attended basic life support and automated external defibrillation training for 1 hour. For comparison of retention of CPR skills, the two groups were evaluated based on 2-minute chest compression performed immediately after training and at 3, 6, and 9 months. The CPR parameters between the two groups were also compared using a generalized linear model.ResultsAt immediately after training, the performance of RTFG was better in terms of average chest compression depth (51.9±1.1 vs. 45.5±1.1, p<0.001) and a higher percentage of adequate chest compression depth (51.0±4.1 vs. 26.9±4.2, p<0.001). This significant difference was maintained until 6 months after training, but there was no difference at 9 months after training. However, there was no significant difference in the chest compression rate and the correct hand position at any time point.ConclusionCPR training with a real-time visual feedback manikin improved skill acquisition in chest compression depth, but only until 6 months after the training. It could be a more effective educational method for basic life support training in laypersons.

Evaluation of Chest Compression Quality and Appropriateness in the Pediatric Cardiopulmonary Resuscitation

Background/Objective: This study aimed to verify the quality and the appropriateness of pediatric CPR chest compressions according to 2015 Korean Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care.Method/Statistical Analysis: The participants of this study were 64 EMT and nursing students who were quailified as BLS providers. Four sets of 5 CPR cycles were performed with one hand and two hands at the ratio of chest compression (30 times) to respiration (2 times), and fatigue was confirmed by NRS(numeral rating scale). Collected data were analyzed using frequency, descriptive statistics, paired t-test, and repeated measure ANOVA by SPSS 22.0.Findings: While the total number of chest compressions (629.6 times vs. 618.3 times, p=.016) and hands-off time (6.6 sec vs. 6.9 sec, p=.006) were effective for one-handed chest compression, average pressure depth (42.2mm vs. 43.8mm, p<.001), sufficient chest compression depth rate (83.0% vs. 89.1%, p=.038) and fatigue (7.0 points vs. 6.2 points, p=.040) were more effective in two-handed chest compressions. In addition, there were significant differences in the average chest compression depth over time(p=.003) and the total elapsed time (p=.332), but no significant difference in inappropriate chest compression.Improvements/Applications: Performing pediatric CPR according to the 2015 Guidelines for Pediatric Cardiopulmonary resuscitation is acceptable, but it is necessary to consider two-hand chest compression more than one hand compression.

Differences in the performance of resuscitation according to the resuscitation guideline terminology during infant cardiopulmonary resuscitation: "Approximately 4 cm" versus "at least one-third the anterior-posterior diameter of the chest".

This study was conducted to investigate the effect of resuscitation guideline terminology on the performance of infant cardiopulmonary resuscitation (CPR). A total of 40 intern or resident physicians conducted 2-min CPR with the two-finger technique (TFT) and two-thumb technique (TT) on a simulated infant cardiac arrest model with a 1-day interval. They were randomly assigned to Group A or B. The participants of Group A conducted CPR with the chest compression depth (CCD) target of "approximately 4 cm" and those of Group B conducted CPR with the CCD target of "at least one-third the anterior-posterior diameter of the chest". Single rescuer CPR was performed with a 15:2 compression to ventilation ratio on the floor. In both chest compression techniques, the average CCD of Group B was significantly deeper than that of Group A (TFT: 41.0 [range, 39.3-42.0] mm vs. 36.5 [34.0-37.9] mm, P = 0.002; TT: 42.0 [42.0-43.0] mm vs. 37.0 [35.3-38.0] mm, P < 0.001). Adequacy of CCD also showed similar results (Group B vs. A; TFT: 99% [82-100%] vs. 29% [12-58%], P = 0.001; TT: 100% [100-100%] vs. 28% [8-53%], P < 0.001). Using the CCD target of "at least one-third the anterior-posterior diameter of the chest" resulted in deep and adequate chest compressions during simulated infant CPR in contrast to the CCD target of "approximately 4 cm". Therefore, changes in the terminology used in the guidelines should be considered to improve the quality of CPR. Clinical Research Information Service; cris.nih.go.kr/cris/en (Registration number: KCT0003486).

Comparison between modified and conventional one-handed chest compression techniques for child cardiopulmonary resuscitation: A randomised, non-blind, cross-over simulation trial.

Chest compression depth (CCD) decreases significantly when performing one-handed chest compression (OHCC). We modified OHCC posture to increase CCD as follows: first, the axis of the compression hand was adjusted to the compression area; second, the opposite hand was wrapped around the elbow of the compression arm. This study compared modified OHCC with conventional OHCC for child cardiopulmonary resuscitation. A total of 46 health-care providers performed 2 min of continuous chest compression using conventional OHCC (trial 1) and modified OHCC (trial 2) in a random order on a 5-year-old-sized child manikin lying on a bed. Chest compression parameters were assessed with an accelerometer and analysed by comparing the mean values of 30-s segments. The average CCD decreased significantly in all segments in both trials (trial 1 (segments 1-4): 40.9 ± 5.6 mm, 39.4 ± 6.6 mm, 38.0 ± 6.9 mm, 36.7 ± 7.3 mm, P < 0.001; trial 2 (segments 1-4): 42.3 ± 5.4 mm, 41.2 ± 6.2 mm, 40.1 ± 6.8 mm, 39.0 ± 6.9 mm, P < 0.001). However, the average CCD in trial 2 was significantly greater in all segments than that in trial 1 (segments 1-4: P = 0.016; P = 0.009; P = 0.004; P = 0.001). The average chest compression rates were comparable in all segments in both trials. By modifying OHCC posture, a deeper mean CCD could be maintained for 2 min than by using conventional OHCC.

Why should we switch chest compression providers every 2 minutes during cardiopulmonary resuscitation?

Objective. This study was conducted to determine whether trained male rescuers could maintain adequate chest compres-sion depth (CCD) for longer than the cur-rent recommended guidelines of 2 minutes. Methods. Forty male medical doctors ad-ministered a 5-minute single rescuer car-diopulmonary resuscitation (CPR) to a manikin on the floor with conventional CPR or randomly administered continu-ous chest compressions (CCC). The ratio of compression to ventilation was set to 30:2 with mouth-to-mouth technique dur-ing conventional CPR. Chest compression data were recorded with an accelerometer device and divided into 1-minute segments for analysis.Results. Although average CCD main-tained the recommended depths through-out 5 minutes in conventional CPR, it de-creased significantly with CCC (1 minute: 55.4 ± 4.5 mm; 2 minutes: 54.2 ± 5.4 mm; 3 minutes: 52.6 ± 5.6 mm; 4 minutes: 51.6 ± 5.5 mm; 5 minutes: 49.9 ± 5.8 mm, p < 0.001). The average chest compression numbers (ACCN) per minute were main-tained over 80/min and have not been changed significantly within 5 minutes in the CCC. However, it didn’t reach to the 80/min and decreased significantly after 3minutes compared to the baseline ACCN during first 1-minute segment in the con-ventional CPR.Conclusions. Despite the chest compres-sion providers being limited to trained male medical doctors, the average CCD decreased significantly within 5minutes with CCC. Although maintaining adequate CCD, ACCN in each minute decreased sig-nificantly after 3minutes in the conventional CPR. Therefore, we should rotate chest compression providers every 2minutes re-gardless of the rescuer’s qualifications and CPR methods.

Rate at 120/min provides qualified chest compression during cardiopulmonary resuscitation

ObjectivesThe quality of cardiopulmonary resuscitation (CPR) is a very important prognostic factor for cardiac arrest. Chest compression is thought to be one of the most important aspects of high-quality CPR. Recent studies have prompted that there may be an interaction between chest compression rate and other factors related to the quality of chest compression. We aimed to investigate the effect of different compression rates on chest compression depth, recoil, and rescuers' fatigue point during CPR. MethodsParticipants performed 2 minutes of chest compression-only CPR after the guiding sounds, at 3 rates (100, 120, and 140 compressions/min) in random sequence. A repeated-measures analysis of variance was used to compare the average chest compression depth and other factors related to the quality of chest compression among the groups. ResultsAs the chest compression rate increases through all the 3 rates, the fractions of chest compressions with complete release and the fractions of chest compressions with sufficient depth were deteriorated at the rate of 140 compressions/min (P < .05), although the average compression depth was above the recommended 2010 guideline depth of 5 cm(P > .05). Of note, the fatigue point at 140 compressions/min happened significantly (P < .05) sooner. ConclusionOur study supported the concern of some that there may be a risk of increasing recommended chest compression rate without providing an upper limit. An appropriate choice may be 120 compressions/min.

2010 American Heart Association recommended compression depths during pediatric in-hospital resuscitations are associated with survival

AimGaps exist in pediatric resuscitation knowledge due to limited data collected during cardiac arrest in real children. The objective of this study was to evaluate the relationship between the 2010 American Heart Association (AHA) recommended chest compression (CC) depth (≥51mm) and survival following pediatric resuscitation attempts. MethodsSingle-center prospectively collected and retrospectively analyzed observational study of children (>1 year) who received CCs between October 2006 and September 2013 in the intensive care unit (ICU) or emergency department (ED) at a tertiary care children's hospital. Multivariate logistic regression models controlling for calendar year and known potential confounders were used to estimate the association between 2010 AHA depth compliance and survival outcomes. The primary outcome was 24-h survival. The primary predictor variable was event AHA depth compliance, prospectively defined as an event with ≥60% of 30-s epochs achieving an average CC depth ≥51mm during the first 5min of the resuscitation. ResultsThere were 89 CC events, 87 with quantitative CPR data collected (23 AHA depth compliant). AHA depth compliant events were associated with improved 24-h survival on both univariate analysis (70% vs. 16%, p<0.001) and after controlling for potential confounders (calendar year of arrest, gender, first documented rhythm; aOR 10.3; CI95: 2.75–38.8; p<0.001). Conclusions2010 AHA compliant chest compression depths (≥51mm) are associated with higher 24-h survival compared to shallower chest compression depths, even after accounting for potentially confounding patient and event factors.

Simplified dispatcher instructions improve bystander chest compression quality during simulated pediatric resuscitation

AimCardiopulmonary resuscitation (CPR) quality is associated with survival outcomes after out-of-hospital cardiac arrest. The objective of this study was to evaluate the effectiveness of simplified dispatcher CPR instructions to improve the chest compression (CC) quality during simulated pediatric cardiac arrest in public places. MethodsAdult bystanders recruited in public places were randomized to receive one of two scripted dispatcher CPR instructions: (1) “Push as hard as you can” (PUSH HARD) or (2) “Push approximately 2 inches” (TWO INCHES). A pediatric manikin with realistic CC characteristics (similar to a 6-year-old child), and a CPR recording defibrillator was used for quantitative CC data collection during a 2-min simulated pediatric scenario. The primary outcome was average CC depth treated as a continuous variable. Secondary outcomes included compliance with American Heart Association (AHA) CPR targets. Analysis was by two-sided unpaired t-test and Chi-square test, as appropriate. Results128 out of 140 providers screened met inclusion/exclusion criteria and all 128 consented. The average CC depth (mean (SEM)) was greater in PUSH HARD compared to TWO INCHES (43 (1) vs. 36 (1) mm, p<0.01) and met AHA targets more often (39% (25/64) vs. 20% (13/64), p=0.02). CC rates trended higher in the PUSH HARD group (93 (4) vs. 82 (4) CC/min, p=0.06). More providers did not achieve full chest recoil with PUSH HARD compared to TWO INCHES (53% (34/64) vs. 75% (48/64), p=0.01). ConclusionsSimplified dispatcher assisted pediatric CPR instructions: “Push as hard as you can” was associated with lay bystanders providing deeper and faster CCs on a simulated, 6-year-old pediatric manikin. However, percentage of providers leaning between CC increased. The potential effect of these simplified instructions in younger children remains unanswered.

배근력과 심폐소생술의 가슴압박과의 관련성

Purpose : The purpose of the study is to investigate the quality and relevance of back strength or chest compression which is applied by isotonic exercise of hip joint. Methods : Subjects were 37 students who participated in the BLS course and accepted the informed consent from December 7 to 8, 2012. During CPR performance, back strength was measured by the researcher. CPR was used the manikin for practical training with using PC, conducted by standard CPR for 2 minutes, Quality of chest compressions included average chest compression depth, rate, and recoil ratio. Results : Back strength (kg) is related to the chest compression depth (mm) (r

Induction of a shorter compression phase is correlated with a deeper chest compression during metronome-guided cardiopulmonary resuscitation: a manikin study

ObjectivesRecent studies have shown that there may be an interaction between duty cycle and other factors related to the quality of chest compression. Duty cycle represents the fraction of compression...

심폐소생술 구조자의 무릎 높이 정도가 흉부압박의 질에 미치는 효과

본 연구는 심폐소생술 시행 시 구조자의 무릎이 바닥으로부터 10 cm 높은 위치와 바닥 위치 간에서 흉부압박의 질에 차이가 있는지를 알아보고자 시행하였다. G광역시의 G대학 응급구조과 1학년 재학생으로 심폐소생술 교육 과정을 이수한 66명 중, 무작위추출과정을 통해 2011년 11월 8일부터 9일까지 실험군 31명, 대조군 32명으로 선정하였다. 바닥으로부터 10 cm 위치(재질: B4 Copy Paper)와 바닥 위치에는 공통으로 매트리스(재질: PVC, 사이즈: <TEX>$185{\times}125{\times}0.65cm$</TEX>)를 깔고 2분 동안 흉부압박 만을 시행하였다. 실험 처치는 Resusci Anne 마네킨 1대를 사용하였으며, Laerdal PC SkillReporting System으로 시행결과를 기록하였다. 수집된 자료는 SPSS 14.0 for Window으로 <TEX>$x^2$</TEX>-test와 Fisher's exact probability test, Mann-Whitney U-test, Wilcoxon signed rank test를 사용하였다. 연구결과, 심폐소생술 구조자의 무릎이 바닥으로부터 10 cm 높은 위치가 바닥 위치보다 흉부압박 적절한 깊이(회), 평균 흉부압박 깊이(mm)가 더 효과적이었는데, 신장 170 cm 이하 그룹, 몸무게 65 kg 이하 그룹에서 흉부압박의 적절한 깊이(회), 평균 흉부압박 깊이(mm)가 효과적 이었다. This study was conducted to examine the differences of the quality of chest compression between 10 cm higher position of rescuer's knee from the bottom and its bottom position during implementation of CPR. It selected randomly subjects out of 66 students who attend the Dept. of Emergency Medical Technology in G college, G metropolitan city as the first grader and divided them into 31 experimental group and 32 control group from Nov. 8 to 9, 2011. Mattress was spread 10 cm higher from the bottom(material: B4 Copy Paper) and on the bottom(material: PVC, size: <TEX>$185{\times}125{\times}0.65cm$</TEX>) and only chest compression was conducted for 2 minutes. Experiment was conducted with 1 Resusci Anne mannequin and the results of experiment were recorded with Laerdal PC Skill Reporting System. Data collected were analyzed with <TEX>$x^2$</TEX>-test and Fisher's exact probability test using SPSS 14.0 for Window, Mann-Whitney U-test, and Wilcoxon signed rank test. As a result of the study, it was found that 10 cm higher position of rescuer knee from the bottom than the bottom position and group below 170 cm in their height and 65 kg in their weight were more effective in proper depth of chest compression and average chest compression depth.

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

BackgroundThe aim of this study was to measure chest compression decay during simulated advanced life support (ALS) in a cardiac arrest manikin model.Methods19 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.ResultsBased 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).ConclusionsIn 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.

Objective assessment of cardiopulmonary resuscitation skills of 10–11-year-old schoolchildren using two different external chest compression to ventilation ratios

To objectively evaluate how effectively children can perform cardiopulmonary resuscitation CPR) 2 months after a single, 2h training session and establish whether or not their performance is affected by the ratio of external chest compressions to ventilations used. Eighty-five schoolchildren aged 10-11 years old were given a 2-h CPR training programme. After 2 months they were randomised into two groups and asked to perform CPR on a resuscitation skills reporter manikin for 3min at a ratio of 30:2 followed by 5min rest, then for 3min at 15:2 (or vice versa). Chest compression depths and ventilation volumes were recorded on a laptop computer and analysed using the Hills and Armitage crossover trial design. The school children were found to be capable of performing effective CPR 2 months after a single training session. In both groups the percentage of chest compressions, of depth recommended by current CPR guidelines, was greater when the 15:2 ratio was being used (P<0.001). The average chest compression depth was significantly greater when the children were performing CPR at a ratio of 15:2 (P<0.001). The compression to ventilation ratio used did not affect the average volume or percentage of effective ventilations given. However, in both groups, the ventilation variables showed enhanced performance during the second period of CPR. Children as young as 10-11 years are capable of performing effective CPR after a single, 2h training session in cardiopulmonary resuscitation given in school. This age group are able to achieve greater depth of chest compressions, when using a ratio of 15:2 rather than 30:2.

Instructions to “push as hard as you can” improve average chest compression depth in dispatcher-assisted cardiopulmonary resuscitation

Cardiopulmonary resuscitation (CPR) with adequate chest compression depth appears to improve first shock success in cardiac arrest. We evaluate the effect of simplification of chest compression instructions on compression depth in dispatcher-assisted CPR protocol. Data from two randomized, double-blinded, controlled trials with identical methodology were combined to obtain 332 records for this analysis. Subjects were randomized to either modified Medical Priority Dispatch System (MPDS) v11.2 protocol or a new simplified protocol. The main difference between the protocols was the instruction to "push as hard as you can" in the simplified protocol, compared to "push down firmly 2in. (5cm)" in MPDS. Data were recorded via a Laerdal ResusciAnne SkillReporter manikin. Primary outcome measures included: chest compression depth, proportion of compressions without error, with adequate depth and with total release. Instructions to "push as hard as you can", compared to "push down firmly 2in. (5cm)", resulted in improved chest compression depth (36.4 mm vs. 29.7 mm, p<0.0001), and improved median proportion of chest compressions done to the correct depth (32% vs. <1%, p<0.0001). No significant difference in median proportion of compressions with total release (100% for both) and average compression rate (99.7 min(-1) vs. 97.5 min(-1), p<0.56) was found. Modifying dispatcher-assisted CPR instructions by changing "push down firmly 2in. (5cm)" to "push as hard as you can" achieved improvement in chest compression depth at no cost to total release or average chest compression rate.