Decompression Cardiopulmonary Resuscitation Research Articles

Abstract 385: Comparison of Rapid Implementation of Automated Head and Thorax Elevation With Active Compression Decompression Cardiopulmonary Resuscitation and an Impedance Threshold Device versus National Outcome Data: A Prospective Observational Study

Background: Pre-clinical work has shown automated head and thorax elevation with active compression decompression CPR and an impedance threshold device (AHUP-CPR) improved 24-hour neurological survival. Propensity matched studies of out-of-hospital-cardiac arrest (OHCA) patients have shown a time dependent association between survival to hospital discharge (SHD) and application of AHUP CPR.Hypothesis: Rapid application of AHUP CPR for OHCA will have a higher incidence of SHD compared to national data. Methods: This is an ongoing prospective observational study of patients from an AHUP-CPR registry of non-traumatic adult OHCA receiving AHUP CPR as part of first responder care. OHCA patients from pre-hospital sites that consistently implemented rapid AHUP CPR were included. Patient demographics, arrest characteristics, ROSC, SHD, and SHD with favorable neurological function, defined as a Cerebral Performance Category score of 1 or 2, were recorded. Data are reported as means ± SD. Combined 2021 and 2022 data from the Cardiac Arrest Registry to Enhance Survival (CARES) were used for comparison of the primary study endpoint, SHD, and secondary endpoints. Chi-square testing was used to compare outcomes. Results: Of 11 registry sites, 7 (US States AL, FL, IL, MN, OK, TN, VA) met inclusion criteria and 1457 patients from January 2020 to June 2023 were enrolled. Average age was 65 ± 16.4 years, 61.8% (901) were male, and 71% (1035) received AHUP CPR. Average time (mm:ss) from 9-1-1 call to start of CPR was 9:52 (6:47) and time to start of AHUP CPR was 12:59 (5:51). Presenting rhythms were: asystole 47.8% (696), PEA 25.8% (376), and VF 20.5% (298). For all AHUP patients, SHD was 13.6% (198) versus 9.2% (26316/286525) for CARES (p < 0.0001). SHD with favorable neurological function was higher for AHUP (10.3% (150) versus 7.3% for CARES (20889), p < 0.0001) and ROSC (29.4% (428) vs 27.0% (77301), p = 0.039). Conclusions: In an unadjusted analysis, the incidence of SHD, ROSC, and neurologically favorable SHD with rapid implementation of AHUP-CPR was higher than nationally reported data. These results support prior findings of a time sensitive association between survival and time to AHUP-CPR. Additional analyses and study are needed for confirmation.

Abstract 11244: Active Decompression During Device Assisted Elevation of the Head and Thorax, an Impedance Threshold Device, and Active Compression Decompression Cardiopulmonary Resuscitation is Needed for Sustained Hemodynamic Benefit in a Porcine Model of Prolonged Cardiac Arrest

Introduction: Active compression decompression cardiopulmonary resuscitation (CPR), an impedance threshold device (ITD), and automated device-assisted controlled head up positioning, collectively termed AHUP CPR, work synergistically to lower intracranial pressure, augment venous return to the heart and significantly improve neurological survival versus conventional (C)-CPR in animals and patients in cardiac arrest. The current study focused on the role of active decompression (AD) during prolonged AHUP CPR, since AD can be difficult to perform manually for an extended period. Hypothesis: Full AD is needed to optimize hemodynamics during prolonged AHUP CPR Methods: Six female and male farm pigs (~40 kg) were sedated, intubated, anesthetized, and monitored. After 8 min of untreated ventricular fibrillation followed by ≥ 30 min of AHUP CPR with an automated device, AHUP CPR was continued except that AD was intentionally reduced from an average of 3.33 ± 0.37 cm of lift to 0 cm lift above the resting neutral position as this is the amount of decompression that occurs with C-CPR and passive chest wall recoil. After 1 min of AHUP CPR with 0 cm lift, AD was progressively increased back to 3 cm of lift over 3 min. Hemodynamics (mean ± SD) were compared using Student’s t test, where p<0.05 was considered statistically significant. Results Coronary perfusion pressure (CorPP) (p<0.005), cerebral perfusion pressure (CerPP) (p<0.001), and ETCO2 (p<0.0001) significantly decreased after AD was discontinued (Fig.1). With restoration of AD to 3 cm, CorPP (p<0.009) and ETCO2 (p<0.001) significantly improved and CerPP trended higher (p=0.084). Conclusion During prolonged (≥ 30 min) AHUP CPR in pigs, active lift of the chest wall is essential to maintain stable hemodynamics. Hemodynamics deteriorated rapidly with intentional loss of AD, but could be partially restored with resumption of AD.

Evaluation of abdominal compression–decompression combined with chest compression CPR performed by a new device: Is the prognosis improved after this combination CPR technique?

IntroductionThis study was designed to compare the outcomes of standard cardiopulmonary resuscitation (STD-CPR) and combined chest compression and abdominal compression–decompression cardiopulmonary resuscitation (CO-CPR) with a new device following out-of-hospital cardiac arrest (OHCA). Moreover, we investigated whether patient prognosis improved with this combination treatment.MethodsThis trial was a single-centre, prospective, randomized trial, and a blinded assessment of the outcomes was performed. A total of 297 consecutive patients with OHCA were initially screened, and 278 were randomized to the STD-CPR group (n = 135) or the CO-CPR group (n = 143). We compared the proportions of patients who achieved a return of spontaneous circulation (ROSC), survived to hospital admission and survived to hospital discharge. In addition, we also performed the Kaplan–Meier analysis with a log-rank test at the end of the follow-up period to compare the survival curves of the two groups.ResultsThe differences were not statistically significant in the proportion of patients who achieved ROSC [31/135 (23.0%) versus 35/143 (24.5%)] and survived to hospital admission [28/135 (20.7%) versus 33/143 (23.1%)] between the CO-CPR group and STD-CPR group. However, there was a significant difference in the proportion of patients who survived to hospital discharge [16/135 (11.9%) versus 7/143 (4.9%)] between the two groups. Nine patients (6.7%) in the CO-CPR group and 2 patients (1.4%) in the STD group showed good neurological outcomes according to the cerebral performance category (CPC) scale score, and the difference was statistically significant (P = 0.003). The Kaplan–Meier curves showed that the patients in the CO-CPR group achieved better survival benefits than those in the STD-CPR group at the end of the follow-up period (log-rank P = 0.007).ConclusionCO-CPR was more beneficial than STD-CPR in terms of survival benefits in patients who have suffered out-of-hospital cardiac arrest.Trial registration Chinese Clinical Trial Registry, registered number: ChiCTR2100049581. Registered 30 July 2021- Retrospectively registered. http://www.medresman.org.cn/uc/index.aspx.

Faster time to automated elevation of the head and thorax during cardiopulmonary resuscitation increases the probability of return of spontaneous circulation

ObjectivesResuscitation in the Head Up position improves outcomes in animals treated with active compression decompression cardiopulmonary resuscitation and an impedance threshold device (ACD + ITD CPR).We assessed impact of time to deployment of an automated Head Up position (AHUP) based bundle of care after out-of-hospital cardiac arrest on return of spontaneous circulation (ROSC). MethodsObservational data were analyzed from a patient registry. Patients received treatment with 1) ACD + and/or automated CPR 2) an ITD and 3) an AHUP device. Probability of ROSC (ROSCprob) from the 9-1-1 call to AHUP device placement was assessed with a restricted cubic spline model and linear regression. ResultsOf 11 sites, 6 recorded the interval from 9-1-1 to AHUP device (n = 227). ROSCprobfor all rhythms was 34%(77/227). Median age (range) was 66 years (19-101) and 68% men. TheROSCprobfor shockable rhythms was 47%(18/38). Minutes from 9-1-1 to AHUP device (median, range) varied between sites: 1) 6.4(4,15), 2) 8.0(5,19), 3) 9.9(4, 12), 4) 14.1(6, 36), 5) 15.9(6, 34), 6) 19.0(8, 38),(p = 0.0001).ROSCprobalso varied; 1) 55.1%(16/29), 2) 60%(3/5), 3) 50%(3/6), 4) 22.7%(17/75), 5) 26.4%(9/34), and 6) 37.1%(29/78), (p = 0.019). For all rhythms between 4 and 12 min (n = 85),ROSCprobdeclined 5.6% for every minute elapsed (p = 0.024). For shockable rhythms, between 6 and 15 min (n = 23),ROSCprobdeclined 9.0% for every minute elapsed (p = 0.006). ConclusionsFaster time to deployment of an AHUP based bundle of care is associated with higher incidence of ROSC. This must be considered when evaluating and implementing this bundle.

Mathematical model of modified hybrid pump mechanism for cardiopulmonary resuscitation

Background and objectiveThe “Cardiac pump theory” and “Thoracic pump theory” are representative theories of cardiopulmonary resuscitation (CPR) mechanisms. Based on these theories, many studies on mathematical modeling have been performed to help understand hemodynamics during CPR. However, there are parts that do not yet properly reflect the physiology of CPR. Therefore, this study aims to develop a lumped parameter model of CPR that can more accurately reflect the current CPR physiology. MethodsBy adding compartments of the superior and inferior vena cava of the thoracic cavity to the existing CPR model, and the “Hybrid pump” mechanism was applied to simulate CPR. To compare the hemodynamics of the conventional CPR model and the developed CPR model, various conditions, such as active compression–decompression CPR with an impedance threshold valve device (ACD–CPR+ITV), head-up-tilt (HUT), and head-down-tilt (HDT), were simulated. The coronary perfusion pressure (CPP) was compared by modulating the compression ratio of the atrium and ventricle with the thoracic pump factor. ResultsThe result for the comparison of coronary blood flow showed that the existing model is predominant in the compression phase, whereas the developed model is dominant in the relaxation phase. ACD–CPR + ITV results showed that the CPP decreased by 5 % in the existing model, and increased by about 46 % in the developed model, revealing a distinct hemodynamic difference between the two models. Likewise, as a result of comparing the hemodynamic differences of the two models according to the changes in tilt angle, the HUT showed similar trends, while the HDT showed slightly different results. The CPP varied accordingly with the ratio of the ventricular and atrial thoracic pump factor. ConclusionComparison of the hemodynamics with the existing model by simulating various conditions showed that the developed CPR model reflects the CPR physiology better. The model suggests that the hemodynamics may vary depending on the ventricle and atrium compression ratio. This study may provide an important basis for helping understand various situations and patient-specific hemodynamic characteristics during CPR through in-depth research, such as patient-specific model and parameter optimization.

Controlled sequential elevation of the head and thorax combined with active compression decompression cardiopulmonary resuscitation and an impedance threshold device improves neurological survival in a porcine model of cardiac arrest

Aim of the studyControlled sequential elevation of the head and thorax (CSE) during active compression decompression (ACD) cardiopulmonary resuscitation (CPR) with an impedance threshold device (ITD) has been shown to increase cerebral perfusion pressure and cerebral blood flow in previous animal studies as compared to the traditional supine position. The potential for this novel bundled treatment strategy to improve survival with intact neurological function is unknown. MethodsFemale farm pigs were sedated, intubated, and anesthetized. Central arterial and venous access were continuously monitored. Regional brain tissue perfusion (CerO2) was also measured transcutaneous. Ventricular fibrillation (VF) was induced and untreated for 10 min. Pigs were randomized to (1) Conventional CPR (C-CPR) flat or (2) ACD + ITD CSE CPR that included 2 min of ACD + ITD with the head and heart first elevated 10 and 8 cm, and then gradual elevation over 2 min to 22 and 9 cm, respectively. After 19 min of CPR, pigs were defibrillated and recovered. A veterinarian blinded to the intervention assessed cerebral performance category (CPC) at 24 h. A neurologically intact outcome was defined as a CPC score of 1 or 2. Categorical outcomes were analyzed by Fisher's exact test and continuous outcomes with an unpaired student's t-test. ResultsIn 16 animals, return of spontaneous circulation rate was 8/8 (100%) with ACD + ITD CSE and 3/8 (25%) for C-CPR (p = 0.026). For the primary outcome of neurologically intact survival, 6/8 (75%) pigs had a CPC score 1 or 2 with ACD + ITD CSE versus 1/8 (12.5%) with C-CPR (p = 0.04). Coronary perfusion pressure (mmHg, mean ± SD) was higher with CSE at 18 min (41 ± 24 versus 10 ± 5, p = 0.004). rSO2 (%, mean ± SD) and ETCO2 (mmHg, mean ± SD) values were higher at 18 min with CSE (32 ± 9 versus 17 ± 2, p = 0.01, and 55 mmHg ± 10 versus 21 mmHg ± 4, p < 0.001), respectively. ConclusionsThe novel bundled resuscitation approach of CSE with ACD + ITD CPR increased favorable neurological survival versus C-CPR in a swine model of cardiac arrest.

Elevation of head and thorax increases cerebral perfusion pressure and lowers intracranial pressure after restoration of spontaneous circulation in a porcine model of cardiac arrest

Aim: Pre-clinical studies have shown that a controlled sequential head and thorax elevation during active compression decompression (ACD) cardiopulmonary resuscitation (CPR) with an impedance threshold device (ITD) improves cerebral blood flow vs. the flat position. The optimal head and thorax position after return of spontaneous circulation (ROSC) is unknown. The aim of this study is to determine whether head and thorax elevation is beneficial post-ROSC.

Abstract 259: Controlled Sequential Elevation of the Head and Thorax Combined With Active Compression Decompression Cardiopulmonary Resuscitation and an Impedance Threshold Device Improves Neurological Survival in a Swine Model of Cardiac Arrest

Introduction: Survival rates after cardiac arrest with intact brain function remain poor and are not uniformly improved with a single intervention. A bundle of care approach to CPR that enhances cerebral and coronary circulation while simultaneously lowering intracranial pressure (ICP) provides new opportunity to improve neurological survival. Hypothesis: Active compression decompression (ACD) CPR and an impedance threshold device (ITD) to regulate intrathoracic pressure with controlled sequential elevation of the head and thorax (CSE) to lower ICP and increase cerebral and coronary (CoPP) perfusion pressures, will increase neurologically intact survival when compared to a conventional (C) CPR in the flat position in pigs. Methods: Female farm pigs were sedated, intubated, and anesthetized. Central arterial and venous access were continuously monitored. Regional brain tissue perfusion (CerO2) was also measured transcutaneously. Ventricular fibrillation was induced and untreated for 10 minutes. Pigs were randomized to 1) C-CPR flat or 2) CSE ACD+ITD CPR that included 2 min of ACD+ITD with the head and heart first elevated 10 and 8 cm, respectively, and then further elevation over 2 min to 22 and 9 cm, respectively. After 19 min of CPR, pigs were defibrillated and recovered. A veterinarian blinded to the intervention assessed cerebral performance category (CPC) at 24 hours. A neurologically intact outcome was defined as a CPC score of 1 or 2. Categorical outcomes were analyzed by Chi-Square and continuous outcomes with an unpaired student’s t-test. All p-values are unadjusted. Results: Return of spontaneous circulation rate was 8/8 (100%) with CSE and 2/8 (25%) for C-CPR (p = 0.002). For the primary outcome of neurologically intact survival, 6/8 (75%) pigs survived with CPC 1 or 2 with CSE versus 1/8 (12.5%) with C-CPR (p = 0.012). CoPP (mmHg, mean ± SD) was higher with CSE at 18 minutes (41 ± 24 vs 10 ± 5, p = 0.004). CerO2 (%, mean ± SD) and ETCO 2 (mmHg, mean ± SD) values were higher at 18 minutes with CSE (32.2 ± 8.5 vs 16.5 ± 2.1, p = 0.003, and 54.9 ± 8.6 vs 19.1 ± 7.0, p &lt; 0.001), respectively. Conclusions: The novel bundled resuscitation approach of CSE with ACD+ITD CPR increased neurologically intact survival 6-fold versus C-CPR in a swine model of cardiac arrest.

Monitoring mechanical impedance of the thorax with compression and decompression cardiopulmonary resuscitation device

To reduce the complications of cardiopulmonary resuscitation (CPR) and increase its effectiveness, the quality of CPR must be measured and feedback provided to the CPR practitioner. Although CPR ancillary devices that attach sensors to measure the compression frequency and depth have been used, these devices did not previously capture the parameters necessary to determine whether the compression position was appropriate, or whether the thorax was deformed by fracture or other causes. In this study, we proposed a system for measuring the mechanical impedance of a patient’s thorax using a load cell and an accelerometer, incorporated into a CPR ancillary device; the mechanical impedance measurements enabled monitoring of the characteristics and deformations of the thorax during in vitro experiments using dummies, and in an animal experiment using two pigs. When CPR was performed, sensors attached to the CPR assist device measured the compression force and movement, and then the single frequency elements of force and velocity at chest compression frequency were calculated. The mechanical impedance can be determined by calculating the ratio of the obtained force to the velocity. Dummies with different elastic moduli show differences in mechanical impedance. In the animal experiment using pigs, the mechanical impedance of the pig’s thorax steadily decreased in response to successive chest compressions. The mechanical impedance system proposed in this study may be useful in the development of new methods to rapidly measure the mechanical properties of the human body or other complex structures.

Abstract 138: A Before and After Study of Active Compression Decompression Cardiopulmonary Resuscitation With the Impedance Threshold Device in a Large Urban Pre-Hospital System

Introduction: Active Compression Decompression cardiopulmonary resuscitation with an impedance threshold device (ACD+ITD CPR) is available for use in the United States. However, little is known regarding integration of this CPR system into a large urban prehospital system with short response times, routine use of mechanical CPR and ITD, and transport of patients to cardiac arrest centers. This is an ongoing before and after study of the implementation of ACD+ITD CPR in non-traumatic cardiac arrest cases 6 months pre and post protocol change. Hypothesis: Neurologically intact rates of survival, defined by Cerebral Performance Category (CPC) score of 1 or 2, would be higher post protocol. Methods: Basic life support first responders (n = 420) and paramedics (n = 207) underwent training including didactic and hands-on sessions to learn ACD+ITD CPR. The protocol included ACD+ITD CPR initially, with the option to transition to mechanical CPR at 15 minutes. Demographics, response time, CPR duration, initial rhythm, signs of perfusion during CPR, and return of spontaneous circulation (ROSC) were recorded prospectively by first responders. Chart review was performed to determine survival to hospital admission and CPC score at discharge. Results: Training occurred October 2016 to March 2017, with protocol change on May 1, 2017. Cases from November 2016-April 2017 (n = 136) and May 2017-November 2017 (n= 103) were reviewed. Complete data were available for 128 subjects pre-protocol change (94%) and 96 subjects (94%) post. Age, gender, response time, rhythm, total CPR time, and rates of bystander CPR and witnessed arrest were similar between groups. Post protocol change, 87% (89/102) received ACD+ITD CPR with median ACD+ITD CPR time of 15 minutes (range 2-300). Pre-protocol, 6/128 (4.7%) subjects survived with CPC score 1 or 2, versus 8/96 (13.5%) subjects post (difference 8.8%, 95% CI 1%-17%). ROSC rates were similar (pre: 54/127, 42.5% post: 44/93, 47%, difference 4.8%, 95% CI -8% - 18%) Conclusions: The change in protocol was straightforward with a high rate of adherence of the system for the recommended duration of therapy. Results are suggestive of a higher rate of neurological survival with the routine use of ACD+ITD CPR in a small cardiac arrest patient population.

Life-Threatening and Suspicious Lesions Caused by Mechanical Cardiopulmonary Resuscitation

Chest compression devices for mechanical cardiopulmonary resuscitation (CPR) have become more common. Here, we report the case of a young woman who attempted resuscitated with LUCAS™2 after she was found unconscious at home. At autopsy, we found extensive intramuscular hemorrhages in posterior neck, between the scapulae, and in the lumbar region. Investigation of internal organs showed injuries to the lung, spleen, and kidney. The extension of the injuries gave rise to suspicion of homicide by smothering, which police investigation subsequently did not support. The pattern of injury could be attributed to automatic compression decompression CPR with LUCAS™2.The injuries may have been lethal had the patient survived. For the forensic pathologists, it is important to remain updated on developments in treatment techniques to avoid pitfalls when interpreting injury.Larger studies, prospective or retrospective, may be able to qualify the possible risks of automatic compression decompression CPR even further.

Head and thorax elevation during active compression decompression cardiopulmonary resuscitation with an impedance threshold device improves cerebral perfusion in a swine model of prolonged cardiac arrest

Aim of the studyAs most cardiopulmonary resuscitation (CPR) efforts last longer than 15min, the aim of this study was to compare brain blood flow between the Head Up (HUP) and supine (SUP) body positions during a prolonged CPR effort of 15min, using active compression-decompression (ACD) CPR and impedance threshold device (ITD) in a swine model of cardiac arrest. MethodsVentricular fibrillation (VF) was induced in anesthetized pigs. After 8min of untreated VF followed by 2min of ACD-CPR+ITD in the SUP position, pigs were randomized to 18min of continuous ACD-CPR+ITD in either a 30° HUP or SUP position. Microspheres were injected before VF and then 5 and 15min after start of CPR. ResultsThe mean blood flow (ml/min/g, mean±SD) to the brain after 15min of CPR was 0.42±0.05 in the HUP group (n=8) and 0.21±0.04 SUP (n=10), respectively, (p<0.01). The HUP group also had statistically significantly lower intracranial pressures and higher calculated cerebral perfusion pressures after 5, 15, 19 (before adrenaline) and 20 (after adrenaline) minutes of HUT versus SUP CPR. ConclusionsAfter prolonged ACD-CPR+ITD in the HUP position, brain blood flow was 2-fold higher versus the SUP position. These positive findings provide strong pre-clinical support to proceed with a clinical evaluation of elevation of the head and thorax during ACD-CPR+ITD in humans in cardiac arrest.

The future is now: neuroprotection during cardiopulmonary resuscitation.

Survival with favorable neurological function after cardiac arrest remains low. The purpose of this review is to identify recent advances that focus on neuroprotection during cardiopulmonary resuscitation (CPR). Multiple strategies have been shown to enhance neuroprotection during CPR. Brain perfusion during CPR is increased with therapies such as active compression decompression CPR and intrathoracic pressure regulation that improve cardiac preload and decrease intracranial pressure. Head Up CPR has been shown to decrease intracranial pressure thereby increasing cerebral perfusion pressure and cerebral blood flow. Sodium nitroprusside enhanced CPR increases cerebral perfusion, facilitates heat exchange, and improves neurologic survival in swine after cardiac arrest. Postconditioning has been administered during CPR in laboratory settings. Poloxamer 188, a membrane stabilizer, and ischemic postconditioning have been shown to improve cardiac and neural function after cardiac arrest in animal models. Postconditioning with inhaled gases protects the myocardium, with more evidence mounting for the potential for neural protection. Multiple promising neuroprotective therapies are being developed in animal models of cardiac arrest, and are in early stages of human trials. These therapies have the potential to be bundled together to improve rates of favorable neurological survival after cardiac arrest.

Treatment of non-traumatic out-of-hospital cardiac arrest with active compression decompression cardiopulmonary resuscitation plus an impedance threshold device

BackgroundA recent out-of-hospital cardiac arrest (OHCA) clinical trial showed improved survival to hospital discharge (HD) with favorable neurologic function for patients with cardiac arrest of cardiac origin treated with active compression decompression cardiopulmonary resuscitation (CPR) plus an impedance threshold device (ACD+ICD) versus standard (S) CPR. The current analysis examined whether treatment with ACD+ITD is more effective than standard (S-CPR) for all cardiac arrests of non-traumatic origin, regardless of the etiology. MethodsThis is a secondary analysis of data from a randomized, prospective, multicenter, intention-to-treat, OHCA clinical trial. Adults with presumed non-traumatic cardiac arrest were enrolled and followed for one year post arrest. The primary endpoint was survival to hospital discharge (HD) with favorable neurologic function (Modified Rankin Scale score≤3). ResultsBetween October 2005 and July 2009, 2738 patients were enrolled (S-CPR=1335; ACD+ITD=1403). Survival to HD with favorable neurologic function was greater with ACD+ITD compared with S-CPR: 7.9% versus 5.7%, (OR 1.42, 95% CI 1.04, 1.95, p=0.027). One-year survival was also greater: 7.9% versus 5.7%, (OR 1.43, 95% CI 1.04, 1.96, p=0.026). Nearly all survivors in both groups had returned to their baseline neurological function by one year. Major adverse event rates were similar between groups. ConclusionsTreatment of out-of-hospital non-traumatic cardiac arrest patients with ACD+ITD resulted in a significant increase in survival to hospital discharge with favorable neurological function when compared with S-CPR. A significant increase survival rates was observed up to one year after arrest in subjects treated with ACD+ITD, regardless of the etiology of the cardiac arrest.

AP035 Active compression–decompression (ACD) cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrest

AP035 Active compression–decompression (ACD) cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrest

AS03 Use of an impedance threshold device with active compression decompression cardiopulmonary resuscitation improves survival with good neurologic function following cardiac arrest from non-traumatic etiologies

AS03 Use of an impedance threshold device with active compression decompression cardiopulmonary resuscitation improves survival with good neurologic function following cardiac arrest from non-traumatic etiologies

AS09 Active compression decompression cardiopulmonary resuscitation and augmentation of negative intrathoracic pressure is neuro-protective in patients with an out-of-hospital cardiac arrest

AS09 Active compression decompression cardiopulmonary resuscitation and augmentation of negative intrathoracic pressure is neuro-protective in patients with an out-of-hospital cardiac arrest

Treatment of out-of-hospital cardiac arrest with an impedance threshold device and active compression decompression cardiopulmonary resuscitation improves survival with good neurological outcome: Results from the resqtrial

Treatment of out-of-hospital cardiac arrest with an impedance threshold device and active compression decompression cardiopulmonary resuscitation improves survival with good neurological outcome: Results from the resqtrial

Mechanical active compression–decompression cardiopulmonary resuscitation (ACD-CPR) versus manual CPR according to pressure of end tidal carbon dioxide (P ETCO 2) during CPR in out-of-hospital cardiac arrest (OHCA)

Aim In animal and human studies, measuring the pressure of end tidal carbon dioxide (P ETCO 2) has been shown to be a practical non-invasive method that correlates well with the pulmonary blood flow and cardiac output (CO) generated during cardiopulmonary resuscitation (CPR). This study aims to compare mechanical active compression–decompression (ACD) CPR with standard CPR according to P ETCO 2 among patients with out-of-hospital cardiac arrest (OHCA), during CPR and with standardised ventilation. Methods This prospective, on a cluster level, pseudo-randomised pilot trial took place in the Municipality of Göteborg. During a 2-year period, all patients aged >18 years suffering an out-of-hospital cardiac arrest (OHCA) of presumed cardiac etiology were enrolled. The present analysis included only tracheally intubated patients in whom P ETCO 2 was measured for 15 min or until the detection of a pulse-giving rhythm. Results In all, 126 patients participated in the evaluation, 64 patients in the mechanical chest compression group and 62 patients in the control group. The group receiving mechanical ACD-CPR obtained the significantly highest P ETCO 2 values according to the average ( p = 0.04), initial ( p = 0.01) and minimum ( p = 0.01) values. We found no significant difference according to the maximum value between groups. Conclusion In this hypothesis generating study mechanical ACD-CPR compared with manual CPR generated the highest initial, minimum and average value of P ETCO 2. Whether these data can be repeated and furthermore be associated with an improved outcome after OHCA need to be confirmed in a large prospective randomised trial.

Shock outcome prediction before and after CPR: A comparative study of manual and automated active compression–decompression CPR

We report on a study designed to compare the relative efficacy of manual CPR (M-CPR) and automated mechanical CPR (ACD-CPR) provided by an active compression-decompression (ACD) device. The ECG signals of out-of-hospital cardiac arrest patients of cardiac aetiology were analysed just prior to, and immediately after, cardiopulmonary resuscitation (CPR) to assess the likelihood of successful defibrillation at these time points. The cardioversion outcome prediction (COP) measure previously developed by our group was used to quantify the probability of return of spontaneous circulation (ROSC) after counter-shock and was used as a measure of the efficacy of CPR. An initial validation study using COP to predict shock outcome from the patient data set resulted in a performance of 60% specificity achieved at 100% sensitivity on a blind test of the data. This is comparable with previous studies and provided confidence in the robustness of the technique across hardware platforms. Significantly, the COP marker also displayed an ability to stratify according to outcomes: asystole, ventricular fibrillation (VF), pulseless electrical activity (PEA), normal sinus rhythm (NSR). We then used the validated COP marker to analyse the ECG data record just prior to and immediately after the chest compression segments. This was initially performed for 87 CPR segments where VF was both the pre- and post-CPR waveform. An increase in the mean COP values was found for both CPR types. A signed rank sum test found the increase due to manual CPR not to be significant (p>0.05) whereas the automated CPR was found to be significant (p<0.05). This increase was larger for the automated CPR (1.26, p=0.024) than for the manual CPR (0.99, p=0.124). These results indicate that the application of CPR does indeed provide beneficial preparation of the heart prior to defibrillation therapy whether manual or automated CPR is applied. The COP marker shows promise as a definitive, quantitative determinant of the immediate positive effect of both types of CPR regardless of the details of use. In work of a more exploratory nature we then used the validated COP marker to analyse the ECG pre- and post-CPR for all rhythm types (212 traces). We show a significant increase in the COP measure (p<0.001 in both cases) as indicated by a shift in the median COP marker distribution values. This increase was more pronounced for automated ACD-CPR than for manual CPR. However, a detailed statistical analysis carried out between the groups adjusted for pre-CPR value showed no significant difference between the two methods of CPR (p=0.20). Similarly, adjusting for length of CPR showed no significant difference between the groups. Secondary, subgroup analysis of the ECG according to the length of time for which CPR was performed showed that both types of CPR led to an increase in the likelihood of successful defibrillation after increasing durations of CPR, however results were less reliable after longer periods of continuous CPR.