Skeletal chest injuries secondary to cardiopulmonary resuscitation

Cardiopulmonary resuscitation-associated injuries in still-/newborns, infants and toddlers in a German forensic collective

INTRODUCTION

Cardiopulmonary resuscitation (CPR) may lead to injuries. Forensic experts are sometimes confronted with claims that fatal injuries were caused by chest compressions during CPR rather than by assaults. We want to answer, how often CPR-associated injuries are present in younger children and if they may mimic injuries caused by abuse.

MATERIAL AND METHODS

All autopsy records of the Institute of Legal Medicine in Leipzig, Germany in a 6-year study period were used (2011-2016). There were 3664 forensic autopsies in total, comprising 97 autopsies of children ≤4 years. After exclusion criteria we were able to include 51 cases in the study. Following this, all CPR-related variables were collected according to the 'Utstein style'. Standard procedures were used for statistical evaluation of the data.

RESULTS

The most common cause of cardiac arrest was SIDS. The mean duration of CPR was 50min. Bystander CPR was performed in 43.1%. In no single case death was declared without at least partly professional CPR. Most of the children were first resuscitated out-of-hospital (41.2%). 27.5% of the children had at least one CPR injury without preference to an age group. None of the recorded CPR-associated injuries were considered significant or life-threatening. The duration of CPR or presence of bystander CPR did not correlate to the presence of any detected injury.

CONCLUSION

Skeletal injuries and relevant injuries to the soft tissue and organs seem to occur only very rarely after pediatric CPR. Whenever such injuries are diagnosed, the children should be examined thoroughly for potential abuse.

The optimum chest compression site with regard to heart failure demonstrated by computed tomography

BACKGROUND

To determine the optimum chest compression site during cardiopulmonary resuscitation (CPR) with regard to heart failure (HF) by applying three-dimensional (3D) coordinates on computed tomography (CT).

METHODS

This retrospective, cross-sectional study involved adults who underwent echocardiography and CT on the same day from 2007 to 2017. Incomplete CT images or information on HF, cardiac medication between echocardiography and CT, or thoracic abnormalities were excluded. Cases were checked whether they had HF through symptom/sign assessment, N-terminal pro-B type natriuretic peptide, and echocardiography. We set the xiphisternal joint's midpoint as the reference (0, 0, 0) to draw a 3D coordinate system, designating leftward, upward, and into-the-thorax directions as positive. The coordinate of the maximum LV diameter's midpoint (P_max.LV) was identified.

RESULTS

Enrolled were 148 patients (63.0±15.1 years) with 87 females and 76 HF cases. P_max.LV of HF cases was located more leftwards, lower, and deeper than non-HF cases (5.69±0.98, -1.51±1.67, 5.76±1.09 cm vs. 5.00±0.83, -0.99±1.36, 5.25±0.71 cm, all p<0.05). Fewer HF cases had their LV compressed than non-HF cases (59.2% vs. 77.8%, p=0.025) when being compressed according to the current guidelines. The aorta (vs. LV) was compressed in 85.5% and 81.9% of HF and non-HF cases, respectively, at 3 cm above the xiphisternal joint. At 6cm above the joint, the highest allowable position according to the current guidelines, all victims would have their aorta compressed directly during CPR rather than the LV.

CONCLUSIONS

The lowest possible sternum just above the xiphisternal joint should be compressed especially for HF patients during CPR.

Effectiveness of feedback with a smartwatch for high-quality chest compressions during adult cardiac arrest: A randomized controlled simulation study

Previous studies have demonstrated the potential for using smartwatches with a built-in accelerometer as feedback devices for high-quality chest compression during cardiopulmonary resuscitation. However, to the best of our knowledge, no previous study has reported the effects of this feedback on chest compressions in action. A randomized, parallel controlled study of 40 senior medical students was conducted to examine the effect of chest compression feedback via a smartwatch during cardiopulmonary resuscitation of manikins. A feedback application was developed for the smartwatch, in which visual feedback was provided for chest compression depth and rate. Vibrations from smartwatch were used to indicate the chest compression rate. The participants were randomly allocated to the intervention and control groups, and they performed chest compressions on manikins for 2 min continuously with or without feedback, respectively. The proportion of accurate chest compression depth (≥5 cm and ≤6 cm) was assessed as the primary outcome, and the chest compression depth, chest compression rate, and the proportion of complete chest decompression (≤1 cm of residual leaning) were recorded as secondary outcomes. The proportion of accurate chest compression depth in the intervention group was significantly higher than that in the control group (64.6±7.8% versus 43.1±28.3%; p = 0.02). The mean compression depth and rate and the proportion of complete chest decompressions did not differ significantly between the two groups (all p>0.05). Cardiopulmonary resuscitation-related feedback via a smartwatch could provide assistance with respect to the ideal range of chest compression depth, and this can easily be applied to patients with out-of-hospital arrest by rescuers who wear smartwatches.

Flail Chest Following Failed Cardiopulmonary Resuscitation

Following the death of a woman with blunt force chest trauma, the question was asked how common was the finding at autopsy of a flail chest in decedents after failed cardiopulmonary resuscitation. It was suggested in court that this was an uncommon occurrence. To address this issue, autopsy cases in adults (>18 years) with rib fractures attributable to cardiopulmonary resuscitation were taken from the files of Forensic Science SA over a 7-year period from 2008 to 2014. Flail chest injuries were defined as those arising from fractures at two sites in at least three consecutive ribs. From 236 cases with rib fractures attributed to resuscitation, a total of 43 flail chest injuries were found in 35 cases (14.8%). The majority occurred in the 60-79-year-old age group. These data suggest that flail chest injuries are a more common sequelae of cardiopulmonary resuscitation than has been previously appreciated in autopsy cases, particularly in the elderly.

Aortic Dissection in a Survivor after Cardiopulmonary Resuscitation

We describe a case of traumatic aortic dissection associated with cardiac compression in a patient with anaphylactic cardiac arrest who underwent cardiopulmonary resuscitation (CPR). A 54-year-old man who was scheduled to undergo surgery for gastric cancer went into cardiac arrest caused by an anaphylactic reaction to prophylactic antibiotics in the operating room. Veno-arterial extracorporeal membrane oxygenation (ECMO) was performed. CPR, including chest compressions, was performed for 35 minutes, and the patient was transferred to the intensive care unit (ICU) after spontaneous circulation returned. The patient received ECMO for 9 hours until confirmation of normal cardiac function on transthoracic echocardiography (TTE). Twenty days after cardiac arrest, an aortic dissection and fractures in the left fourth and fifth ribs due to chest compression were detected by abdominal computed tomography. The DeBakey type III aortic dissection extended from the distal arch of the thoracic aorta to the proximal level of the renal artery, involving the celiac trunk. It was considered an uncomplicated type B aortic dissection with no sign of malperfusion of the major vessels. This case demonstrates the potential traumatic injuries that can occur after CPR and encourages proper management of mechanical complications in cardiac arrest survivors.

Concealed resuscitation-related injuries as reversible cause of recurrent arrest following extracorporeal cardiopulmonary resuscitation

A life-threatening cardiopulmonary resuscitation (CPR)-related injury can cause recurrent arrest after return of circulation. Such injuries are difficult to identify during resuscitation, and their contribution to failed resuscitation can be missed given the limitations of conventional CPR. Extracorporeal cardiopulmonary resuscitation (ECPR), increasingly being considered for selected patients with potentially reversible etiology of arrest, may identify previously occult CPR-related injuries by restoring arterial pressure and flow. Herein, we describe two cases of severe CPR-related injuries contributing to recurrent arrest. Each case had ECPR implemented within 60 minutes of the start of CPR. After the presumed cardiac etiology had been addressed with percutaneous coronary intervention, life-threatening cardiovascular injuries with recurrent arrest were noted, and resuscitative thoracotomy was performed under ECPR. One patient survived to hospital discharge.

ECPR may provide an opportunity to identify and correct severe resuscitation-related injuries causing recurrent arrest. Chest compression depth >6 cm, especially in older women, may contribute to these injuries.

Parenchymal lung injuries related to standard cardiopulmonary resuscitation

OBJECTIVES

We analyzed chest computed tomographic scan to evaluate parenchymal lung injury and its clinical significance in patients who received standard cardiopulmonary resuscitation and were resuscitated from cardiac arrest.

METHODS

We enrolled nontraumatic out-of-hospital cardiac arrest patients older than 19 years who had been admitted to the emergency department in cardiac arrest and successfully resuscitated after cardiopulmonary resuscitation. Chest computed tomography was obtained immediately after return of spontaneous circulation (ROSC). To allocate the area of lung contusion, we divided both hemithoraces into 3 regions longitudinally, and each part was subdivided into 4 segments except the lower part of the left lung. To stratify the severity of lung contusion, each segment was scored depending on the area of lung contusion. Oxygen index (OI) was measured at the time of ROSC, 24, 48, and 72 hours and 1 week after cardiac arrest.

RESULTS

Lung contusion was developed in 37 (41%) patients and median lung contusion score (LCS) was 17 (12-26). Lung contusion was not associated with hospital mortality (P = .924) or length of intensive care unit stay (P = .446). The OI at the time of ROSC was lower in patients with LCS greater than 23 than that in patients with LCS less than or equal to 23 (126 [93-224] vs 278 [202-367]; P = .008); however, the OI at the other timelines was not different between patients with LCS greater than 23 and patients with LCS less than or equal to 23.

CONCLUSION

Extensive lung contusion is associated with a lower oxygenation index at the time of ROSC, but did not affect the resuscitation outcome.

Thoracic Spine Fracture in a Survivor of Out-of-Hospital Cardiac Arrest with Mechanical CPR

This is a report of a thoracic vertebral fracture in a 79-year-old male survivor of out-of-hospital cardiac arrest with chest compressions provided by a LUCAS 2 (Physio-Control Inc.; Lund Sweden) device. This is the first such report in the literature of a vertebral fracture being noted in a survivor of cardiac arrest where an automated compression device was used. Marshall RT , Kotecha H , Chiba T , Tennyson J . Thoracic spine fracture in a survivor of out-of-hospital cardiac arrest with mechanical CPR. Prehosp Disaster Med. 2016;31(6):684-686.

CPR-associated right ventricular rupture in the setting of pulmonary embolism

Cardiopulmonary resuscitation (CPR) is an inherently traumatic procedure. Successful resuscitations are often complicated by iatrogenic injuries to structures of the neck, thorax, or abdomen. Rib and sternal fractures are the most frequently induced injuries. However, rare and life-threatening trauma to vital organs such as the heart may also occur during CPR. We describe a novel case of CPR-associated right ventricular rupture in a woman with acute-on-chronic pulmonary embolism and no known pre-existing cardiac disease. We propose that chest compressions in the setting of elevated right ventricular pressure resulted in cardiac rupture, in this case.

Intra-thoracic injuries associated with cardiopulmonary resuscitation - Frequent and serious

AIM OF THE STUDY

The aim of the study was to evaluate prevalence, seriousness and risk factors of intra-thoracic injuries (ITI) injuries associated with CPR in non-survivors after out-of-hospital cardiac arrest.

METHODS

This was a prospective forensic autopsy cohort study conducted in a single institution. Pathologists recorded autopsy data using standardized protocol which contained data from external and internal examination of the body focused on ITI.

RESULTS

In total, 80 persons were included in this study. CPR-associated injuries were found in 93.7% of cases; majority of injuries were skeletal chest fractures (rib fractures in 73.7%, sternal fractures in 66.3%). ITI were identified in 41.2% of cases. Contusion of at least one lung lobe was found in 31.2%, lung laceration in 2.5%, and hemothorax in 5.0% of cases. Transmural heart contusion was identified in 17.5% of cases; hemopericard on the grounds of right atrium rupture of aortic rupture was revealed in 8.7% of cases. Risk factor analysis did not show any statistically significant correlation between ITI and any of general data (age, gender, BMI, cause of death, season of the year or location where the body was found) or CPR specifications (type and duration of CPR, manner of chest compressions). A strong correlation between ITI and skeletal chest fractures was proven.

CONCLUSION

ITI present frequent and serious complications of unsuccessful CPR. ITI could contribute to the death only provided the fact that ROSC had been achieved. Correct performance of chest compressions according to guidelines is the best way to avoid ITI.

Do-not-attempt-cardiopulmonary-resuscitation decisions: an evidence synthesis

Background

Cardiac arrest is the final common step in the dying process. In the right context, resuscitation can reverse the dying process, yet success rates are low. However, cardiopulmonary resuscitation (CPR) is a highly invasive medical treatment, which, if applied in the wrong setting, can deprive the patient of dignified death. Do-not-attempt-cardiopulmonary-resuscitation (DNACPR) decisions provide a mechanism to withhold CPR. Recent scientific and lay press reports suggest that the implementation of DNACPR decisions in NHS practice is problematic.

Aims and objectives

This project sought to identify reasons why conflict and complaints arise, identify inconsistencies in NHS trusts’ implementation of national guidelines, understand health professionals’ experience in relation to DNACPR, its process and ethical challenges, and explore the literature for evidence to improve DNACPR policy and practice.

Methods

A systematic review synthesised evidence of processes, barriers and facilitators related to DNACPR decision-making and implementation. Reports from NHS trusts, the National Reporting and Learning System, the Parliamentary and Health Service Ombudsman, the Office of the Chief Coroner, trust resuscitation policies and telephone calls to a patient information line were reviewed. Multiple focus groups explored service-provider perspectives on DNACPR decisions. A stakeholder group discussed the research findings and identified priorities for future research.

Results

The literature review found evidence that structured discussions at admission to hospital or following deterioration improved patient involvement and decision-making. Linking DNACPR to overall treatment plans improved clarity about goals of care, aided communication and reduced harms. Standardised documentation improved the frequency and quality of recording decisions. Approximately 1500 DNACPR incidents are reported annually. One-third of these report harms, including some instances of death. Problems with communication and variation in trusts’ implementation of national guidelines were common. Members of the public were concerned that their wishes with regard to resuscitation would not be respected. Clinicians felt that DNACPR decisions should be considered within the overall care of individual patients. Some clinicians avoid raising discussions about CPR for fear of conflict or complaint. A key theme across all focus groups, and reinforced by the literature review, was the negative impact on overall patient care of having a DNACPR decision and the conflation of ‘do not resuscitate’ with ‘do not provide active treatment’.

Limitations

The variable quality of some data sources allows potential overstatement or understatement of findings. However, data source triangulation identified common issues.

Conclusion

There is evidence of variation and suboptimal practice in relation to DNACPR decisions across health-care settings. There were deficiencies in considering, discussing and implementing the decision, as well as unintended consequences of DNACPR decisions being made on other aspects of patient care.

Future work

Recommendations supported by the stakeholder group are standardising NHS policies and forms, ensuring cross-boundary recognition of DNACPR decisions, integrating decisions with overall treatment plans and developing tools and training strategies to support clinician and patient decision-making, including improving communication.

Study registration

This study is registered as PROSPERO CRD42012002669.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Estimation of optimal pediatric chest compression depth by using computed tomography

OBJECTIVE

This study aimed to compare the optimal chest compression depth for infants and children with that of adults when the simulated compression depth was delivered according to the current guidelines.

METHODS

A total of 467 consecutive chest computed tomography scans (93 infants, 110 children, and 264 adults) were reviewed. The anteroposterior diameter and compressible diameter (CD) for infants and children were measured at the inter-nipple level and at the mid-lower half of the spine for adults. Compression ratio (CR) to CD was calculated at simulated 1/4, 1/3, and 1/2 antero-posterior compressions in infants and children, and simulated 5- and 6-cm compressions in adults.

RESULTS

In adults, the CRs to CD at simulated 5- and 6-cm compression depth were 41.7±0.16%, 50.0±7.3% respectively. In children and infants, the CRs to CD at 1/3 chest compression were 55.1±2.4% and 51.8±2.4%, respectively, and at 1/2 chest compression, CRs were 82.7±3.7% and 77.7±3.6%, respectively. The CRs to CD of 4-cm compression depth in infants and 5-cm compression depth in children were 74.4±10.9%, 62.5±8.7%, respectively. The CRs to CD for children and infants were significantly higher than in adults (P<0.001). The CR to CD of 4-cm compression depth in children was almost similar to that of 6-cm compression depth in adults (50.0± 6.9% vs. 50.0±7.3%, P=0.985).

CONCLUSION

Current pediatric guidelines for compression depth are too deep compared to those in adults. We suggest using 1/3 of the anteroposterior chest diameter or about 4 cm in children and less than 4 cm in infants.

Restart the heart

Early bystander cardiopulmonary resuscitation and rapid defibrillation are the most important factors for favourable outcomes after out of hospital cardiac arrest (OHCA)-as the new American Heart Association/European Resuscitation Council (AHA/ERC) guidelines emphasise. The patient in our case was a healthy young man who had a witnessed cardiac arrest due to a chest collision with the goalkeeper during a football match. Basic life support was immediately provided by his teammates until an automated external defibrillator was brought to the scene. Blunt cardiac injury (BCI) may result in injured myocardium or arrhythmias. Ventricular fibrillation due to BCI in absence of structural cardiac disease is one of the main causes of OHCA in young healthy athletes with high mortality rates. We demonstrate important aspects of the recently released guidelines on cardiac arrest and the chain of survival by the leading societies.

Internal Mammary Artery Injury Related to Chest Compressions in a Patient with Post-cardiac Arrest Syndrome

Although high-quality cardiopulmonary resuscitation (CPR) is essential for survival from cardiac arrest, chest compressions can also sometimes lead to life-threatening chest injuries. In addition, post-cardiac arrest syndrome patients often have coagulopathy due to therapeutic hypothermia, mechanical hemodynamic support, or both. Therefore, when progressive anemia and prolonged shock are detected in patients who have received CPR, identifying the cause of hemorrhagic shock is crucial. We herein present an interesting case of hemorrhagic shock due to an internal mammary artery injury secondary to CPR that was detected by computed tomography and invasive angiography.

Comparison of complications secondary to cardiopulmonary resuscitation between out-of-hospital cardiac arrest and in-hospital cardiac arrest

OBJECTIVE

The aim of this study was to assess whether there was a significant difference in the complications of cardiopulmonary resuscitation (CPR) between out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA) survivors using multidetector computed tomography (MDCT).

SUBJECTS AND METHODS

We performed a retrospective analysis of prospective registry data. We enrolled both OHCA and IHCA patients who underwent successful CPR. We classified chest injuries secondary to chest compression into rib fractures, sternum fractures, and uncommon complications such as lung contusions and extrathoracic complications. We compared these complications according to CPR locations. We also analysed risk factors for CPR complications using multiple regression analysis and classification and regression tree analysis.

RESULTS

During the study period, a total of 148 patients were included in the primary analysis. Rib fractures were detected more in OHCA survivors than in IHCA survivors (74 patients (83.2%) vs. 37 patients (62.7%), p=0.05), and frequency of multiple rib fractures was higher in OHCA survivors than IHCA survivors (69 patients (77.5%) vs. 34 patients (57.6%), p=0.01). Although other complications were not significantly different between the groups, there was a trend for OHCA survivors to sustain more serious and direct high-energy related complications. Older age, longer CPR, and OHCA were significantly associated with incidence of rib fractures, multiple rib fractures, and number of rib fractures.

CONCLUSIONS

Rib fractures were more likely to occur in OHCA survivors, and serious complications tended to occur more often in OHCA compared to IHCA survivors.

Cardiopulmonary Resuscitation-induced Thoracic Vertebral Fracture: A Case Report

Thoracic vertebral fractures are very unusual complications of cardiopulmonary resuscitation (CPR). A 78-year-old man developed cardiac arrest after aspirating and conventional CPR was performed. After recovery, the patient had complete paraplegia (Frankel grade A). Magnetic resonance image of spine showed a dislocation fracture with hematoma at T6 thoracic level. Computed tomography scan of chest revealed the fracture of sternum. After the patient's condition became stable with subsequent medical treatment, posterior decompression and pedicle screw fixation was performed. The patient had uneventful postoperative course with continued rehabilitation. Thus, this report emphasizes that care should be taken especially in elderly patients with fragile bone to recognize such rare complication of chest compression; however, adequate compressions to ensure circulation should be maintained.

Aortic luminal thrombus and intramural hematoma after cardiopulmonary resuscitation

We describe the case of a patient with an intramural hematoma and floating thrombus after cardiopulmonary resuscitation. The 92-year old man had a cardiac arrest due to ventricular fibrillation and witnesses immediately initiated manual cardiopulmonary resuscitation. Transesophageal echocardiography was performed immediately on hospital admission because the patient was in cardiogenic shock. In addition to an akinetic anterior wall, examination of the descending thoracic aorta demonstrated an intramural hematoma and a floating intra-aortic thrombus at a distance of 40cm from the dental arch. There was no aortic dissection. The thrombus was attributed to aortic compression during cardiopulmonary resuscitation. Although the aortic thrombus and intramural hematoma were not associated with any complications in this patient, insertion of an intra-aortic balloon may have led to aortic rupture or embolic events. Transesophageal echocardiography should be performed, when available, prior to insertion of an intra-aortic balloon for counterpulsation in patients who have undergone cardiopulmonary resuscitation.

Frequency and number of resuscitation related rib and sternum fractures are higher than generally considered

AIM OF THE STUDY

This study aimed to establish the incidence, number and location of CPR-related skeletal chest injuries (SCI) and to investigate the influence of age, gender, changes in resuscitation guidelines and technique of resuscitation.

METHODS

We analysed SCI in 2148 patients who had undergone resuscitation for non-traumatic cardiac arrest, as shown by autopsies performed at the Institute of Forensic Medicine in Ljubljana in the period 2004-2013.

RESULTS

External cardiac massage caused SCI in 86% of males and in 91% of females; sternum fractures occurred in 59% of males and 79% of females, rib fractures in 77% of males and 85% of females and sternocostal separations in 33% of males and 12% of females. The average number of all SCI per person was thus almost the same in males and females: 10.95 vs. 10.96. The percentage of patients injured and the number of SCI increased with age. Changes in resuscitation guidelines were also identified as a factor contributing to the incidence and number of SCI. No adverse effect of the use of LUCAS was found.

CONCLUSION

It is generally considered that at least 1/3 of resuscitated patients sustain rib fractures and at least 1/5 sustains sternum fractures. However, our study showed that these injuries are much more frequent and that increased compression rate and depth cause more SCI. Since in the period 2011-2013 accompanying severe injuries occurred in only 1.85% of cases, the resuscitation technique has not yet jeopardised patient's safety, but further close monitoring is needed.

Cardiac arrest diagnostic accuracy of 9-1-1 dispatchers: a prospective multi-center study

INTRODUCTION

We sought to determine the ability of 9-1-1 dispatchers to accurately determine the presence of out-of-hospital cardiac arrest (OOHCA) over the telephone, and to determine the frequency with which CPR instructions are initiated and chest compressions delivered in patients not in cardiac arrest.

METHODS

We conducted a multi-center, prospective cohort study of adult OOHCA patients not witnessed by EMS for which resuscitation was attempted. Dispatchers were not health care professionals and received 6 weeks of training followed by a 6-month preceptorship. We reviewed 9-1-1 call digital recordings for all unconscious patients for which the possibility of cardiac arrest was considered using a piloted standardized data collection sheet.

RESULTS

We reviewed 2260 recordings occurring between January 2008 and October 2009. Among those, 1536 were confirmed OOHCA, and 724 were not. Among the 1536 confirmed OOHCA cases, 1012 were recognized by dispatchers and 524 were not. Among the 724 cases not in cardiac arrest, dispatchers suspected cardiac arrest was present in 490 and absent in 234. OOHCA diagnostic accuracy characteristics were: sensitivity 65.9% (95% CI 63.5-68.2%), specificity 32.3% (95% CI 29.0-35.9%), PPV 67.4%, and NPV 30.9%. Dispatchers believed that OOHCA was present in 490/2260 (21.7%) cases when it was not, resulting in 54/490 (11.0%) patients inappropriately receiving chest compressions, or 54/2260 (2.4%) of the whole cohort.

CONCLUSIONS

Dispatchers had a fair sensitivity and modest specificity for the recognition of OOHCA. We found a very small number of patients receiving CPR when not in cardiac arrest, supporting the current use of dispatch-assisted CPR instructions.

A mechanical chest compressor closed-loop controller with an effective trade-off between blood flow improvement and ribs fracture reduction

Chest compression (CC) is a significant emergency medical procedure for maintaining circulation during cardiac arrest. Although CC produces the necessary blood flow for patients with heart arrest, improperly deep CC will contribute significantly to the risk of chest injury. In this paper, an optimal CC closed-loop controller for a mechanical chest compressor (OCC-MCC) was developed to provide an effective trade-off between the benefit of improved blood perfusion and the risk of ribs fracture. The trade-off performance of the OCC-MCC during real automatic mechanical CCs was evaluated by comparing the OCC-MCC and the traditional mechanical CC method (TMCM) with a human circulation hardware model based on hardware simulations. A benefit factor (BF), risk factor (RF) and benefit versus risk index (BRI) were introduced in this paper for the comprehensive evaluation of risk and benefit. The OCC-MCC was developed using the LabVIEW control platform and the mechanical chest compressor (MCC) controller. PID control is also employed by MCC for effective compression depth regulation. In addition, the physiological parameters model for MCC was built based on a digital signal processor for hardware simulations. A comparison between the OCC-MCC and TMCM was then performed based on the simulation test platform which is composed of the MCC, LabVIEW control platform, physiological parameters model for MCC and the manikin. Compared with the TMCM, the OCC-MCC obtained a better trade-off and a higher BRI in seven out of a total of nine cases. With a higher mean value of cardiac output (1.35 L/min) and partial pressure of end-tidal CO2 (15.7 mmHg), the OCC-MCC obtained a larger blood flow and higher BF than TMCM (5.19 vs. 3.41) in six out of a total of nine cases. Although it is relatively difficult to maintain a stable CC depth when the chest is stiff, the OCC-MCC is still superior to the TMCM for performing safe and effective CC during CPR. The OCC-MCC is superior to the TMCM in performing safe and effective CC during CPR and can be incorporated into the current version of mechanical CC devices for high quality CPR, in both in-hospital and out-of-hospital CPR settings.

Traumatic injuries after mechanical cardiopulmonary resuscitation (LUCAS2): a forensic autopsy study

AIM

The aim of our study was to compare traumatic injuries observed after cardiopulmonary resuscitation (CPR) by means of standard (manual) or assisted (mechanical) chest compression by Lund University Cardiopulmonary Assist System, 2nd generation (LUCAS2) device.

METHODS

A retrospective study was conducted including cases from 2011 to 2013, analysing consecutive autopsy reports in two groups of patients who underwent medicolegal autopsy after unsuccessful CPR. We focused on traumatic injuries from dermal to internal trauma, collecting data according to a standardised protocol.

RESULTS

The study group was comprised of 26 cases, while 32 cases were included in the control group. Cardiopulmonary resuscitation performed by LUCAS2 was longer than manual CPR performed in control cases (study group: mean duration 51.5 min; controls 29.4 min; p = 0.004). Anterior chest lesions (from bruises to abrasions) were described in 18/26 patients in the LUCAS2 group and in 6/32 of the control group. A mean of 6.6 rib fractures per case was observed in the LUCAS2 group, but this was only 3.1 in the control group (p = 0.007). Rib fractures were less frequently observed in younger patients. The frequency of sternal factures was similar in both groups. A few trauma injuries to internal organs (mainly cardiac, pulmonary and hepatic bruises), and some petechiae (study 46%; control 41 %; p = 0.79) were recorded in both groups.

CONCLUSION

LUCAS™2-CPR is associated with more rib fractures than standard CPR. Typical round concentric skin lesions were observed in cases of mechanical reanimation. No life-threatening injuries were reported. Petechiae were common findings.

Computed tomography findings of complications resulting from cardiopulmonary resuscitation

INTRODUCTION

This retrospective study was conducted to evaluate injuries related to cardiopulmonary resuscitation (CPR) and their associated factors using postmortem computed tomography (PMCT) and whole body CT after successful resuscitation.

METHODS

The inclusion criteria were adult, non-traumatic, out-of-hospital cardiac arrest patients who were transported to our emergency room between April 1, 2008 and March 31, 2013. Following CPR, PMCT was performed in patients who died without return of spontaneous circulation (ROSC). Similarly, CT scans were performed in patients who were successfully resuscitated within 72h after ROSC. The injuries associated with CPR were analysed retrospectively on CT images.

RESULTS

During the study period, 309 patients who suffered out-of hospital cardiac arrest were transported to our emergency room and received CPR; 223 were enrolled in the study. The CT images showed that 156 patients (70.0%) had rib fractures, and 18 patients (8.1%) had sternal fractures. Rib fractures were associated with older age (78.0 years vs. 66.0 years, p<0.01), longer duration of CPR (41min vs. 33min, p<0.01), and lower rate of ROSC (26.3% vs. 55.3%, p<0.01). All sternal fractures occurred with rib fractures and were associated with a greater number of rib fractures, higher age, and a lower rate of ROSC than rib fractures only cases. Bilateral pneumothorax was observed in two patients with rib fractures.

CONCLUSIONS

PMCT is useful for evaluating complications related to chest compression. Further investigations with PMCT are needed to reduce complications and improve the quality of CPR.

Complete cardiac rupture associated with closed chest cardiac massage: case report and review of the literature

Chest skeletal injuries are the most frequent complications of external chest massage (ECM) during cardiopulmonary resuscitation, but heart and great vessels lacerations that are indeed very rare. We report the case of a 35-year-old workman who collapsed and underwent ECM by his co-workers for almost 30 min. At autopsy, no external injuries, fractures or bruises of the ribs or sternum, were observed. A hemopericardium with a rupture of the heart was found, with no signs of pre-existent cardiac disease. Bruises of thoracic aortic wall, lung petechiae, a contusion of the liver, and bruises of lumbar muscles were found. The cause of death was due to sudden cardiac death with an extensive cardiac rupture. This is an unusual report of massive heart damage without any skeletal or muscle chest injuries, secondary to cardiopulmonary resuscitation. This kind of cardiac lesions may be considered when thoracic–abdominal trauma, or medical history, is unclear.

The importance of victim chest exposure during cardiopulmonary resuscitation: a simulation study

BACKGROUND

During cardiopulmonary resuscitation (CPR), inaccurate positioning of the rescuer's hand might damage internal organs due to compression around the xiphoid process.

OBJECTIVE

This study aimed to determine whether exposing the victim's chest during CPR would help adequate positioning of a rescuer's hand on the chest.

METHODS

This simulation study included 187 participants. We gave them four photographs each of exposed chests and unexposed chests. Participants were then asked to mark a cross at the center of the chest (CoC) and at the inter-nipple line (INL), and we measured the width of participants' palms to estimate the range of hand contact with the victim's chest. Finally, we compared the position and distribution of the CoC and INL markings and analyzed whether the hand contact range on the victim's chest involved the xiphoid process.

RESULTS

The participants' CoC markings were similar regardless of whether the pictures showed an exposed or unexposed chest (p = 0.638). However, the level of INL marking was significantly lower in pictures of an exposed chest (p < 0.001). When exposing the chest, the distribution of markings was narrower for both CoC (p = 0.001) and INL (p < 0.001). The proportion of CoC markings involving the xiphoid process were lower when the chest was exposed (10.7%) than when was clothed (12.3%) (p < 0.001). Similarly, INL markings involving the xiphoid process followed the same trend in exposed vs. unexposed chest images (0% vs. 1.6%, respectively).

CONCLUSIONS

Exposing the chest during CPR can improve the rescuer's ability to recognize the CoC and INL, leading to more intense chest compression and reducing the risk of inaccurate compression.

[Mechanical resuscitation assist devices]

In Germany 100,000-160,000 people suffer from out-of-hospital cardiac arrest (OHCA) annually. The incidence of cardiopulmonary resuscitation (CPR) after OHCA varies between emergency ambulance services but is in the range of 30-90 CPR attempts per 100,000 inhabitants per year. Basic life support (BLS) involving chest compressions and ventilation is the key measure of resuscitation. Rapid initiation and quality of BLS are the most critical factors for CPR success. Even healthcare professionals are not always able to ensure the quality of CPR measures. Consequently in recent years mechanical resuscitation devices have been developed to optimize chest compression and the resulting circulation. In this article the mechanical resuscitation devices currently available in Germany are discussed and evaluated scientifically in context with available literature. The ANIMAX CPR device should not be used outside controlled trials as no clinical results have so far been published. The same applies to the new device Corpuls CPR which will be available on the market in early 2014. Based on the current published data a general recommendation for the routine use of LUCAS™ and AutoPulse® CPR cannot be given. The preliminary data of the CIRC trial and the published data of the LINC trial revealed that mechanical CPR is apparently equivalent to good manual CPR. For the final assessment further publications of large randomized studies must be analyzed (e.g. the CIRC and PaRAMeDIC trials). However, case control studies, case series and small studies have already shown that in special situations and in some cases patients will benefit from the automatic mechanical resuscitation devices (LUCAS™, AutoPulse®). This applies especially to emergency services where standard CPR quality is far below average and for patients who require prolonged CPR under difficult circumstances. This might be true in cases of resuscitation due to hypothermia, intoxication and pulmonary embolism as well as for patients requiring transport or coronary intervention when cardiac arrest persists. Three prospective randomized studies and the resulting meta-analysis are available for active compression-decompression resuscitation (ACD-CPR) in combination with an impedance threshold device (ITD). These studies compared ACD-ITD-CPR to standard CPR and clearly demonstrated that ACD-ITD-CPR is superior to standard CPR concerning short and long-term survival with good neurological recovery after OHCA.

CPR-related injuries after manual or mechanical chest compressions with the LUCAS™ device: a multicentre study of victims after unsuccessful resuscitation

AIM

The reported incidence of injuries due to cardiopulmonary resuscitation using manual chest compressions (manual CPR) varies greatly. Our aim was to elucidate the incidence of CPR-related injuries by manual chest compressions compared to mechanical chest compressions with the LUCAS device (mechanical CPR) in non-survivors after out-of-hospital cardiac arrest.

METHODS

In this prospective multicentre trial, including 222 patients (83 manual CPR/139 mechanical CPR), autopsies were conducted after unsuccessful CPR and the results were evaluated according to a specified protocol.

RESULTS

Among the patients included, 75.9% in the manual CPR group and 91.4% in the mechanical CPR group (p=0.002) displayed CPR-related injuries. Sternal fractures were present in 54.2% of the patients in the manual CPR group and in 58.3% in the mechanical CPR group (p=0.56). Of the patients in the manual CPR group, there were 64.6% with at least one rib fracture versus 78.8% in the mechanical CPR group (p=0.02). The median number of rib fractures among patients with rib fractures was 7 in the manual CPR group and 6 in the mechanical CPR group. No CPR-related injury was considered to be the cause of death.

CONCLUSION

In patients with unsuccessful CPR after out-of-hospital cardiac arrest, rib fractures were more frequent after mechanical CPR but there was no difference in the incidence of sternal fractures. No injury was deemed fatal by the pathologist.

Chest Compression Injuries Detected via Routine Post-arrest Care in Patients Who Survive to Admission after Out-of-hospital Cardiac Arrest

Abstract Objective. To examine injuries produced by chest compressions in out-of-hospital cardiac arrest (OHCA) patients who survive to hospital admission. Methods. A retrospective cohort study was conducted among 235 consecutive patients who were hospitalized after nontraumatic OHCA in Minnesota between January 2009 and May 2012 (117 survived to discharge; 118 died during hospitalization). Cases were eligible if the patient had received prehospital compressions from an emergency medical services (EMS) provider. One EMS provider in the area was using a mechanical compression device (LUCAS^TM) as standard equipment, so the association between injury and use of mechanical compression was also examined. Prehospital care information was abstracted from EMS run sheets, and hospital records were reviewed for injuries documented during the post-arrest hospitalization that likely resulted from compressions. Results. Injuries were identified in 31 patients (13%), the most common being rib fracture (9%) and intrathoracic hemorrhage (3%). Among those who survived to discharge, the mean length of stay was not statistically significantly different between those with injuries (13.5 days) and those without (10.8 days; p = 0.23). Crude injury prevalence was higher in those who died prior to discharge, had received compressions for >10 minutes (versus ≤10 minutes) and underwent computer tomography (CT) imaging, but did not differ by bystander compressions or use of mechanical compression. After multivariable adjustment, only compression time > 10 min and CT imaging during hospitalization were positively associated with detected injury (OR = 7.86 [95% CI = 1.7-35.9] and 6.30 [95% CI = 2.6-15.5], respectively). Conclusion. In patients who survived OHCA to admission, longer duration of compressions and use of CT during the post-arrest course were associated positively with documented compression injury. Compression-induced injuries detected via routine post-arrest care are likely to be largely insignificant in terms of length of recovery.

Cardiopulmonary resuscitation (CPR)-related posterior rib fractures in neonates and infants following recommended changes in CPR techniques

Posterior rib fractures are highly indicative of non-accidental trauma (NAT) in infants. Since 2000, the "two-thumbs" technique for cardiopulmonary resuscitation (CPR) of newborns and infants has been recommended by the American Heart Association (AHA). This technique is similar to the grip on an infant's thorax while shaking. Is it possible that posterior rib fractures in newborns and infants could be caused by the "two-thumbs" technique? Using computerized databases from three German children's hospitals, we identified all infants less than 12 months old who underwent professional CPR within a 10-year period. We included all infants with anterior-posterior chest radiographs taken after CPR. Exclusion criteria were sternotomy, osteopenia, various other bone diseases and NAT. The radiographs were independently reviewed by the Chief of Pediatric Radiology (MB) and a Senior Pediatrician, Head of the local Child Protection Team (IF). Eighty infants with 546 chest radiographs were identified, and 50 of those infants underwent CPR immediately after birth. Data concerning the length of CPR was available for 41 infants. The mean length of CPR was 11min (range: 1-180min, median: 3min). On average, there were seven radiographs per infant. A total of 39 infants had a follow-up radiograph after at least 10 days. No rib fracture was visible on any chest X-ray. The results of this study suggest rib fracture after the use of the "two-thumbs" CPR technique is uncommon. Thus, there should be careful consideration of abuse when these fractures are identified, regardless of whether CPR was performed and what technique used. The discovery of rib fractures in an infant who has undergone CPR without underlying bone disease or major trauma warrants a full child protection investigation.

KneePR--Substantial injuries caused by unorthodox resuscitation technique

We report a case of cardiopulmonary resuscitation involving chest compressions performed with the rescuer's knee. The substantial injuries caused by this unorthodox technique could have been mistaken for the cause of death were it not for careful scene investigation and documentation.

Compression, distortion and dislodgement of large caliber stents in congenital heart defects caused by cardiopulmonary resuscitation: a case series and review of the literature

Stenting of vascular, extracardiac or lately intracardiac stenosis has become an established interventional treatment for a variety of problems in congenital or acquired heart disease. Most stent procedures are completed successfully and the long-term outcome is favorable in the majority of cases. Stent collapse or deformation is a well recognized entity in peripheral stents and can be attributed to insufficient radial force; it can also be attributed to excessive external forces, like deformation of stents in the right ventricular outflow tract, where external compression is combined with continuous movement caused by the beating heart. The protection of the thoracic cage may prove to be insufficient in extraordinary circumstances, such as chest compression in trauma or cardiopulmonary resuscitation (CPR). In this case series, we describe three patients in whom large endovascular stents were placed to treat significant stenosis of the aorta, the aortic arch or the venous system of the inferior vena cava close to the atrium. In all patients, CPR was necessary during their clinical course for various reasons; after adequate CPR, including appropriate chest compression all patients survived the initial resuscitation phase. Clinical, echocardiographic as well as radiologic re-evaluation after resuscitation revealed significant stent distortion, compression, displacement or additional vascular injury. The possibility of mechanical deformation of large endovascular stents needs to be considered and recognized when performing CPR; if CPR is successful, immediate re-evaluation of the implanted stents--if possible by biplane fluoroscopy--seems mandatory.

Isolated right atrial rupture because of external cardiac massage after coronary artery bypass grafting

Background: Isolated right atrial rupture is a very rare catastrophic complication of cardiopulmonary resuscitation.

Objective: We described a rare case of right atrial rupture after external cardiac massage.

Methods: We reported the case of a 62-year-old male patient who developed excessive bleeding following external cardiac massage for sudden cardiac arrest in the intensive care unit after coronary artery bypass grafting.

Results: This man underwent successful emergency repair of the tear of the right atrium without using cardiopulmonary bypass.

Conclusion: Right atrial rupture can occur after external cardiac massage. An emergency repair is needed.