Impacto das superfícies de compressão na massagem cardíaca durante a reanimação cardiopulmonar: uma revisão integrativa / Impacto de las superficies de compresión en el masaje cardíaco durante la reanimación cardiopulmonar: una revisión integrativa / Impact of compression surfaces on cardiac massage during cardiopulmonary reanimation: an integrative review

Resumo Objetivo sintetizar as evidências disponíveis na literatura sobre os tipos de superfícies de compressão utilizadas na RCP e analisar quais características das superfícies de compressão têm impacto na eficácia da compressão torácica durante a RCP. Método revisão integrativa da literatura, cujos critérios de seleção e inclusão foram: artigos completos, em inglês, português ou espanhol e que respondessem a seguinte questão de pesquisa: "Quais são as características das superfícies de compressão que têm impacto na eficácia das compressões torácicas durante a RCP?". Realizada entre os meses de junho e julho de 2019. Resultados inclui-se 12 artigos de estudos experimentais, cuja extração de dados revelou 13 tipos diferentes de colchões. Em relação às pranchas, seis tamanhos diferentes foram relatados, com diferentes materiais. Constatou-se influências do tipo de superfície de compressão na força necessária para realizar as compressões torácicas. Conclusão as evidências apontam que colchões de maiores dimensões e com tecnologia para redução de pressão e camas mais largas apresentam impactos negativos na qualidade das compressões torácicas. Implicação para prática o conhecimento sobre a influência do tipo e características das superfícies de apoio na qualidade das compressões torácicas podem subsidiar profissionais na escolha e incorporação de tecnologias no ambiente hospitalar.

Resumen Objetivo Sintetizar la evidencia disponible en la literatura sobre los tipos de superficies de compresión utilizadas en la RCP y analizar qué características de las superficies de compresión tienen un impacto en la efectividad de la compresión torácica durante la RCP. Método Revisión bibliográfica integradora, cuyos criterios de selección e inclusión fueron: artículos completos, en inglés, portugués o español y que respondieran a la siguiente pregunta de investigación: "¿Cuáles son las características de las superficies de compresión que inciden en la efectividad de las compresiones torácicas durante la RCP?". Se llevó a cabo entre junio y julio de 2019. Resultados se incluyeron 12 artículos de estudios experimentales, cuya extracción de datos reveló 13 tipos diferentes de colchones. En cuanto a los Tabelaros, se reportaron seis tamaños diferentes, con diferentes materiales. Se encontraron influencias del tipo de superficie de compresión sobre la fuerza requerida para realizar las compresiones torácicas. Conclusión la evidencia señala que los colchones más grandes con tecnología de reducción de presión y las camas más grandes tienen impactos negativos en la calidad de las compresiones torácicas. Implicación para la práctica El conocimiento sobre la influencia del tipo y características de las superficies de apoyo en la calidad de las compresiones torácicas puede ayudar a los profesionales en la elección e incorporación de tecnologías en el ámbito hospitalario.

Abstract Objective To synthesize the available evidence in the literature on the types of compression surfaces used in CPR and to analyze which characteristics of the compression surfaces impact the effectiveness of chest compression during CPR. Method Integrative literature review, whose selection and inclusion criteria were complete articles, in English, Portuguese or Spanish and that answered the following research question: "What are the characteristics of the compression surfaces that impact the effectiveness of chest compressions during CPR?". It was carried out between June and July 2019. Results 12 articles from experimental studies were included. 13 different types of mattresses were found. Regarding the boards, six different sizes and many materials were reported. Influences of the type of compression surface on the force required to perform chest compressions were found. Conclusion Evidence points out that larger mattresses with pressure reduction technology and larger beds have negative impacts on the quality of chest compressions. Implication for practice Knowledge about the influence of the type and characteristics of support surfaces on the quality of chest compressions can support professionals in the choice and incorporation of technologies in the hospital environment.

Parada cardiorrespiratória na pandemia por coronavírus: revisão compreensiva da literatura / Cardiorespiratory arrest in a coronavirus pandemic: comprehensive literature review / Paro cardiorrespiratorio en una pandemia de coronavirus: revisión exhaustiva de la literatura

Objetivo: apresentar atualizações para a ressuscitação cardiopulmonar em pacientes suspeitos e confirmados com COVID-19. Método: revisão compreensiva da literatura, com síntese narrativa das evidências de diretrizes e recomendações da Organização Mundial de Saúde, Associação de Medicina Intensiva Brasileira, American Heart Association, Resuscitation Council UK, American College of Surgions Committee on Trauma e National Association of Emergency Medical Technicians. Resultados: as principais atualizações trazem informações sobre especificidades das manobras de ressuscitação cardiopulmonar; preparação do ambiente, recursos humanos e materiais, reconhecimento da parada cardiorrespiratória e ações iniciais; estratégias de ventilação e acesso invasivo da via aérea; ajustes do ventilador mecânico e manobras de ressuscitação cardiopulmonar em pacientes pronados. Considerações finais: profissionais de saúde envolvidos no atendimento à parada cardiorrespiratória de pacientes suspeitos e/ou confirmados com COVID-19 podem encontrar inúmeros desafios, portanto devem seguir com rigor o protocolo estabelecido para maximizar a efetividade das manobras de ressuscitação e minimizar o risco de contágio pelo vírus e sua disseminação.

Objective: to present updates for cardiopulmonary resuscitation in suspected and confirmed patients with COVID-19. Method: comprehensive literature review with narrative synthesis of the evidence of guidelines and recommendations from World Health Organization, Associação de Medicina Intensiva Brasileira, American Heart Association, Resuscitation Council UK, American College of Surgions Committee on Trauma and National Association of Emergency Medical Technicians. Results: the main updates bring information about the specifics of cardiopulmonary resuscitation maneuvers; preparation of the environment and human and material resources, recognition of cardiorespiratory arrest and initial actions; ventilation and invasive airway access strategies; mechanical ventilator adjustments and cardiopulmonary resuscitation maneuvers in patients in the prone position. Final considerations: health professionals involved in the care of cardiorespiratory arrest of suspected and/or confirmed patients with COVID-19 can face numerous challenges, so they must strictly follow the protocol established to maximize the effectiveness of resuscitation maneuvers and minimize the risk of contagion by the virus and its spread.

Objetivo: apresentar actualizaciones para la reanimación cardiopulmonar en pacientes sospechos os y confirmados con COVID-19. Método: revisión exhaustiva de la literatura con síntesis narrativa de la evidencia de guías y recomendaciones de la Organización Mundial de la Salud, Associação de Medicina Intensiva Brasileira, American Heart Association, Resuscitation Council UK, American College of Surgions Committee on Trauma and National Association of Emergency Medical Technicians. Resultados: las principales actualizaciones aportan información sobre los detalles de las maniobras de reanimación cardiopulmonar; preparación del medio ambiente y recursos humanos y materiales, reconocimiento de paro cardiorrespiratorio y acciones iniciales; estrategias de ventilación y acceso invasivo a las vías aéreas; ajustes del ventilador mecánico y maniobras de reanimación cardiopulmonar en pacientes en decúbito prono. Consideraciones finales: los profesionales de la salud involucrados en la atención del paro cardiorrespiratorio de pacientes sospechosos y/o confirmados con COVID-19 pueden enfrentar numerosos desafíos, por lo que deben seguir estrictamente el protocolo establecido para maximizar la efectividad de las maniobras de reanimación y minimizar el riesgo de contagio por el virus y supropagación.

Effect of Watch-Type Haptic Metronome on the Quality of Cardiopulmonary Resuscitation: A Simulation Study / 대한의료정보학회지

OBJECTIVES: The aim of this study was to test the applicability of haptic feedback using a smartwatch to the delivery of cardiac compression (CC) by professional healthcare providers. METHODS: A prospective, randomized, controlled, case-crossover, standardized simulation study of 20 medical professionals was conducted. The participants were randomly assigned into haptic-first and non-haptic-first groups. The primary outcome was an adequate rate of 100–120/min of CC. The secondary outcome was a comparison of CC rate and adequate duration between the good and bad performance groups. RESULTS: The mean interval between CCs and the number of haptic and non-haptic feedback-assisted CCs with an adequate duration were insignificant. In the subgroup analysis, both the good and bad performance groups showed a significant difference in the mean CC interval between the haptic and non-haptic feedback-assisted CC groups—good: haptic feedback-assisted (0.57–0.06) vs. non-haptic feedback-assisted (0.54–0.03), p < 0.001; bad: haptic feedback-assisted (0.57–0.07) vs. non-haptic feedback-assisted (0.58–0.18), p = 0.005—and the adequate chest compression number showed significant differences— good: haptic feedback-assisted (1,597/75.1%) vs. non-haptic feedback-assisted (1,951/92.2%), p < 0.001; bad: haptic feedbackassisted (1,341/63.5%) vs. non-haptic feedback-assisted (523/25.4%), p < 0.001. CONCLUSIONS: A smartwatch cardiopulmonary resuscitation feedback system could not improve rescuers' CC rate. According to our subgroup analysis, participants might be aided by the device to increase the percentage of adequate compressions after one minute.

Emergency Department Thoracotomy with Clamshell Incision for Traumatic Cardiac Tamponade

The emergency department thoracotomy (EDT) is a bold and challenging procedure, which may be the only chance of survival for some moribund trauma patients. EDT provides ample exposure to the injury site of the heart, enabling an effective open cardiac massage. Clamshell thoracotomy is a rapid and simple procedure that provides excellent exposure to internal structures. Because EDT has more favorable outcomes for penetrating injuries than for blunt injuries, the indication for EDT in patients with blunt trauma should be well established. Cardiac tamponade is a life-threatening condition that requires emergent pericardial decompression. EDT has been associated with successful initial resuscitation for traumatic cardiac arrest with cardiac tamponade. To date, there has not been any reports of clamshell incision via EDT for trauma patients in South Korea. Hence, herein, we describe two cases in which EDT with clamshell incision was implemented for cardiac tamponade with cardiac arrest after blunt trauma.

Initiation of resuscitation in the delivery room for extremely preterm infants: a profile of neonatal resuscitation instructors

OBJECTIVE: The goal of the present study was to examine the decisions of pediatricians who teach neonatal resuscitation in Brazil, particularly those who start resuscitation in the delivery room for newborns born at 23-26 gestational weeks. METHODS: The present study was a cross-sectional study that used electronic questionnaires (Dec/11-Sep/13) sent to instructors of the Neonatal Resuscitation Program of the Brazilian Society of Pediatrics. The primary outcome was the gestational age at which the respondent said that he/she would initiate positive pressure ventilation in the delivery room. Latent class analysis was used to identify the major profiles of these instructors, and logistic regression was used to identify variables associated with belonging to one of the derived classes. RESULTS: Of 685 instructors, 82% agreed to participate. Two latent classes were identified: ‘pro-resuscitation’ (instructors with a high probability of performing ventilation on infants born at 23-26 weeks) and ‘pro-limitation’ (instructors with a high probability of starting ventilation only for infants born at 25-26 weeks). In the multivariate model, compared with the ‘pro-limitation’ class, ‘pro-resuscitation’ pediatricians were more likely to be board-certified neonatologists and less likely to base their decision on the probability of the infant’s death or on moral/religious considerations. CONCLUSION: The pediatricians in the most aggressive group were more likely to be specialists in neonatology and to use less subjective criteria to make delivery room decisions.

Can a Rescuer Gazing Point Intervention Improve the Depth of Chest Compressions in Hands-only Cardiopulmonary Resuscitation? A Randomized Simulation Study

PURPOSE: The aim of this study was to evaluate whether a simple verbal instruction regarding the rescuer gazing point can improve the depth of chest compressions (CCs) in the hands-only cardiopulmonary resuscitation (CPR). METHODS: Participants who took part in basic life support training courses for lay-rescuers were eligible for inclusion in this prospective, single-blinded, cluster randomized controlled study. After the training courses, both the control and the intervention groups performed the hands-only CPR for two minutes on a manikin placed on the ground. Immediately prior to CCs, instructors provided the intervention group with brief verbal instructions to look in the opposite direction of the adducted arm after placing the heel of the hand on the mid-sternum. RESULTS: One hundred and twenty-two participants (61 for each group) were enrolled in this study. The intervention group showed significantly deeper CCs than the control group (47.9±8.2 mm vs. 43±8.4 mm, p<0.01); however, there were no significant differences between the two groups in the quality of chest recoil, CC rate, or duty cycle of CCs. However, the frequency of incorrect hand position was higher in the intervention group when compared with the control group (10.3 [2.3-35.7] vs. 5.7 [0-33.0], p=0.036) CONCLUSION: Instructions to look in the opposite direction of the adducted arm during CCs improved the mean depth of CCs without significant adverse effects on the quality of recoil, CC rate, or duty cycle of CCs. However, the frequency of incorrect hand position was higher in the intervention group than the control group.

Parada cardiorrespiratória / Cardiorespiratory arrest

Os suportes básicos e avançados de vida continuam a ser a chave para melhorar os resultados de sobrevivência da parada cardiorrespiratória (PCR). O objetivo deste artigo é atualizar a abordagem da PCR, enfatizando os diferentes cenários clínicos e individualizando as terapias conforme o ritmo e a etiologia.

Basic life support and advanced cardiovascular life support continue to be the key to improve survival rates of sudden cardiac arrest (SCA). The purpose of this article is to update the approach to SCA, emphasizing the different clinical scenarios and individualizing therapies according to rhythm and etiology.

Right Ventricular Rupture Caused by Prolonged Cardiopulmonary Resuscitation after Sudden Cardiac Arrest / 대한내과학회지

A 46-year-old male arrived at the emergency department with acute dyspnea. On the way to the hospital, heart massage was performed in the ambulance due to asystole on electrocardiography. After 2 hr of resuscitation, sinus rhythm was restored. Extracorporeal life support and an intra-aortic balloon pump were applied due to cardiogenic shock, but the patient showed sustained hypotension. Echocardiography showed moderate pericardial effusion with physiological evidence of cardiac tamponade; emergency pericardiocentesis was performed, which produced bloody pericardial fluid. An explorative sternotomy revealed a massive hematoma in the mediastinum and right ventricular (RV) free wall rupture. After primary repair, echocardiography showed improved left ventricular systolic function and the patient was stable clinically. This case presents RV free wall rupture as an unusual complication of prolonged heart massage. Heart rupture should be considered in hemodynamically unstable patients after prolonged heart massage.

Changes of One-handed Chest Compression Qualities According to Rescuer Fatigue and the Effects of Alternating Hands in the Prehospital Setting: Prospective Randomized Pilot Study using Pediatric Manikin Simulation Trial

PURPOSE: One-handed chest compression (OHCC) technique is performed by one hand. Therefore chest compression (CC) depth might decrease rapidly. This study will evaluate the patterns of CC depth decaying in performing OHCC and assess the effects of alternating the hand which performs CC on the patterns of CC depth decaying. METHODS: This study was designed as a prospective randomized manikin simulation trial. Students of medical college participated. First, 10 students performed OHCC (chest compression:ventilation=30:2) in a pediatric manikin lying on a hard floor for 5 minutes (baseline study). After the baseline study, 32 students were recruited and randomized to group A and B. Group A performed OHCC with hand shift every other cycle (test 1). Group B performed OHCC with hand shift when they feel fatigue (test 2). The compression data were collected using the CPRmeter. The mean compression depths (MCD) were calculated at one minute intervals using the Q-CPR review software. The heart rates were monitored and the fatigue scales were collected every 1 minute. RESULTS: The MCD values were decreased significantly after 1 minute in the baseline study (p<0.05). However they were not changed in test 1 and decreased significantly after 4 minutes in test 2 (p<0.05). The heart rate and the fatigue scales were increased significantly with time in all tests (p<0.05). CONCLUSION: When OHCC was performed without shifting the hand which performed CC, the MCD decreased significantly after 1 minute. However, we could delay the time of decreasing MCD by shifting the hand which performed CC.

The Effect of Counting Numbers out for Giving Breaths on the Interrupting Time and Fraction of Chest Compressions in 2-rescuer Cardiopulmonary Resuscitation: A Manikin Pilot Study

PURPOSE: The aim of this study was to estimate the effect of counting numbers out for giving breaths on the interruption time (IT) of chest compressions (CCs) and chest compression fraction (CCF) in the 2-rescuer cardiopulmonary resuscitation (CPR). METHODS: Thirty medical students were enrolled in this randomized control simulation study, and were randomly divided into the control group and the study group. Both groups performed 2-rescuer CPR for 5-cycles with giving breaths using a bag-mask. Only participants in the study group were instructed to count numbers out for each breath verbally ("one, two") at the end point of each inspiration period and immediately perform CCs at the point of counting "two". RESULTS: However, no differences in terms of depth, rate, incorrect location, and duty cycle of CCs, as well as ventilation volume of each breath, time to delivery of two breaths, and counts of breathing during 1 minute were observed between the two groups. CONCLUSION: The study group had significantly shorter IT and higher CCF compared with the control group. And no significant differences in the other measured parameters of CPR quality were observed between the two groups.

Differences in Hands-off Time According to the Position of a Second Rescuer When Switching Compression in Pre-hospital Cardiopulmonary Resuscitation Provided by Two Bystanders: A Randomized, Controlled, Parallel Study

The change of compressing personnel will inevitably accompany hands off time when cardiopulmonary resuscitation (CPR) is performed by two or more rescuers. The present study assessed whether changing compression by a second rescuer located on the opposite side (OS) of the first rescuer can reduce hands-off time compared to CPR on the same side (SS) when CPR is performed by two rescuers. The scenario of this randomized, controlled, parallel simulation study was compression-only CPR by two laypersons in a pre-hospital situation. Considering sex ratio, 64 participants were matched up in 32 teams equally divided into two gender groups, i.e. , homogenous or heterogeneous. Each team was finally allocated to one of two study groups according to the position of changing compression (SS or OS). Every team performed chest compression for 8 min and 10 sec, with chest compression changed every 2 min. The primary endpoint was cumulative hands-off time. Cumulative hands-off time of the SS group was about 2 sec longer than the OS group, and was significant (6.6 +/- 2.6 sec vs. 4.5 +/- 1.5 sec, P = 0.005). The range of hands off time of the SS group was wider than for the OS group. The mean hands-off times of each rescuer turn significantly shortened with increasing number of turns (P = 0.005). A subgroup analysis in which cumulative hands-off time was divided into three subgroups in 5-sec intervals revealed that about 70% of the SS group was included in subgroups with delayed hands-off time > or = 5 sec, with only 25% of the OS group included in these subgroups (P = 0.033). Changing compression at the OS of each rescuer reduced hands-off time compared to the SS in prehospital hands-only CPR provided by two bystanders.

Out-of-hospital cardiopulmonary resuscitation needs the ventilation / 浙江大学学报·医学版

Cardiopulmonary resuscitation (CPR) is series of rescue measures for saving cardiac arrest patients. Early initiation and good quality of CPR is crucial for increasing chance of survival from out-of-hospital cardiac arrest. In recent years, the CPR guidelines have changed a lot, especially in basic life support. The guideline now pays more attention on chest compression and less to ventilation. CPR with chest compression only and without mouth-to-mouth ventilation is more popular. In this article, we outline the development and recent researches of CPR. As depriving oxygen from a collapsed patient for 6 min may result in poor outcome, the average time for ambulance transport is longer (about 10 to 16 min) in China, which makes rescuers easy to feel fatigue, chest compression only CPR is not suitable in China. Though non-professional rescuers have difficulty to perform mouth-to-mouth ventilation, they generally show a willingness to do so. To strengthen public standard CPR training including mouth-to-mouth ventilation and chest compression, is most important to promote CPR in China.

Effects of chest compressions on cardiorespiratory function in a non-arrested porcine model / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The effects of chest compressions to hemodynamic and respiratory parameters during hands-only cardiopulmonary resuscitation (CPR) in a non-arrested patient who suddenly collapses are confusing. In this research, we investigated the effects of chest compressions in a non-arrested porcine model.</p><p><b>METHODS</b>Fourteen male domestic pigs were randomized into sham control group (SHAM group, only anesthetized and instrumented without chest compression, n = 6) or chest compression group (CC group, 2 minutes of chest compressions, n = 8). Continuous hemodynamic parameters, dynamic lung compliance (Cdyn), and blood gas analysis outcomes were recorded. Serum levels of catecholamine were measured at baseline and 2 minutes, 30 minutes, 4 hours, and 24 hours after chest compressions. Chest computed tomography (CT) was performed at 30 minutes and 24 hours. Conventional histopathology evaluation was performed.</p><p><b>RESULTS</b>After two minutes of chest compressions in the CC group, heart rate and extravascular lung water increased significantly; mean arterial pressure, stroke volume, and global ejection fraction significantly decreased. Cdyn significantly decreased to valley levels at 30 minutes and slowly recovered. Compared with the baseline, serum levels of catecholamine significantly increased at 2 minutes and rapidly decreased 24 hours later. At 30 minutes after chest compressions, chest CT showed local exudation, which was absorbed 24 hours later.</p><p><b>CONCLUSIONS</b>This research showed that 2 minutes of chest compressions causes various heart and lung tissue damage in the normal a normal porcine model. It also impacts the hemodynamic and Cdyn.</p>

Successful resuscitation of cardiac arrest caused by CO2 embolism with intra-aortic injection of epinephrine during off-pump coronary bypass surgery: a case report / 대한마취과학회지

Although compressed gas (CO2) blowers have been used safely to aid accurate grafting during off-pump coronary bypass surgery, hemodynamic collapse due to gas embolism into the right coronary artery may occur. Supportive measures to facilitate gas clearance by increasing the coronary perfusion pressure have been reported to be successful in restoring hemodynamic stability. However, right ventricular dysfunction and atrioventricular nodal ischemia may hinder effective systemic delivery of the vasoactive medications, even when performing resuscitative measures such as direct cardiac massage. We herein report a case of cardiac arrest that was caused by a right coronary gas embolism and that could not be restored by cardiac resuscitation. When supportive measures fail, direct aortic injection of epinephrine to increase the coronary perfusion pressure can be attempted before initiating cardiopulmonary bypass, and this approach may be life-saving in situations that limit systemic drug delivery from the venous side despite the performance of direct cardiac massage.

Center of the Chest Versus Inter-nipple Line in the Selection of a Chest Compression Site by Novice Rescuers

PURPOSE: The aim of this study was to compare the distribution and risk from hand positions applied at the center of the chest (CoC) versus the inter-nipple line (INL) during external chest compression by novice rescuers. METHODS: This simulation study included 105 participants. The participants were given photographs of the unexposed male chest and asked to mark a cross at the center of the chest and at the midpoint of the inter-nipple line. The range of contact with the chest was estimated by measuring the participants' palm width. The median and distribution of the two points were then compared and analyzed to determine whether the range in contact with the chest involved the xiphoid process. RESULTS: The level of the INL was approximately 0.8 cm higher at the sternum than the CoC (p<0.001), while the standard deviation of the CoC [1.8(0.6-3.8)] was higher than that of the INL [1.2(0.4-2.4)] (p<0.001). There were more cases in which the palm range involved the xiphoid process in the CoC group [15(14.3%)] than the INL group [1(0.9%)] (p<0.001). CONCLUSION: For male adult patients, chest compression at the level of the INL by novice rescuers is safer and more intensive than compression at the level of the CoC.

A Telephone Method for Helping Lay Rescuers Perform High Quality Cardiopulmonary Resuscitation

PURPOSE: Dispatcher-assisted telephone instruction during cardiopulmonary resuscitation (CPR) improves the quality of CPR performed by laypersons. However, in Korea, CPR instruction guidelines for bystanders have not made. We therefore studied the effects of verbal instruction on the quality of chest compression. METHODS: Data from two randomized, double-blinded, controlled trials using identical methodology were combined to obtain 175 records for analysis. Subjects were randomized into either a "push as hard as you can and fast" (n=87) or "push down 5~6 cm, 100~120 rate/min" (n=88), verbal instructions in the 2011 Korea Guidelines for Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care (ECC). Data were recorded via a Resusci(R) Anne SkillReporter(TM), Laerdal Medical mannequin. Primary outcome measures included chest compression depth and chest compression rate per minute. RESULTS: The average compression depth and speed of chest compressions did not significantly differ between the two verbal instructions. CONCLUSION: The verbal istructions provided by telephone based on the 2011 Korean Guidelines for CPR and ECC are not effective. The instructions for high quality CPR of layperson should therefore be studied.

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.

A Comparison of Compression Rates on the Quality of Cardiopulmonary Resuscitation

PURPOSE: In cardiopulmonary resuscitation (CPR) there are different opinions on the compression rate that should be applied. The aim of this study was to compare the total number of adequate compressions delivered during a five-minute period among four groups of lay persons (> or =139 min-1, 129-138, 114-128, and 100 times/minute and a depth of >5 cm for five minutes. A total of 86 participants were then divided into four groups based on their mean compression rate. Age, sex, and body mass index were analyzed as factors affecting the compression rates. RESULTS: The group delivering a compression rate above 139 compressions min-1 performed better than those delivering below 114 compressions min-1 (p=0.03). There was no significant difference in the mean compression depth (p=0.13), percentage of incomplete chest recoil (p=0.277), or the percentage of incorrect hand positioning (p=0.091). All participants (except five) performed chest compressions at a rate above 100 compressions min-1. CONCLUSION: Our results suggest that a chest compression rate above 139 compressions min-1 does not deteriorate the quality of compressions compared to a lower chest compression rate (below 114 min-1) during a five-minute period. Most untrained lay people performed chest compressions well, within a range of 100~150 min-1.