Chest compression fraction calculation: A new, automated, robust method to identify periods of chest compressions from defibrillator data – tested in Zoll X Series

Background: Chest compression efficacy determines blood flow in cardiopulmonary resuscitation (CPR) and relies on body mechanics, so resuscitator weight matters. Individuals of insufficient weight are incapable of generating a sufficient downward chest compression force using traditional methods. Aims: This study investigated how a resuscitator's weight affects chest compression efficacy, determined the minimum weight required to perform chest compressions and, for children and adults below this minimum weight, examine alternate means to perform chest compressions. Methods: Volunteers aged 8 years and above were enrolled to perform video-recorded, music-facilitated, compression-only CPR on an audible click-confirming manikin for 2 minutes, following brief training. Subjects who failed this proceeded to alternate modalities: chest compressions by jumping on the lower sternum; and squat-bouncing (bouncing the buttocks on the chest). These methods were assessed via video review. Findings: There were 57 subjects. The 30 subjects above 40kg were all able to complete nearly 200 compressions in 2 minutes. Success rates declined in those who weighed less than 40kg. Below 30 kg, only one subject (29.9 kg weight) out of 14 could achieve 200 effective compressions. Nearly all of the 23 subjects who could not perform conventional chest compressions were able to achieve effective chest compressions using alternate methods. Conclusion: A weight below 40kg resulted in a declining ability to perform standard chest compressions effectively. For small resuscitators, the jumping and squat-bouncing methods resulted in sufficient compressions most of the time; however, chest recoil and injuries are concerns.

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Abstract 17334: The Detrimental Effect of Chest Compression Interruptions on Coronary Perfusion Pressure Dynamics

Circulation ◽

10.1161/circ.132.suppl_3.17334 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Norman A Paradis ◽

Karen L Moodie ◽

Christopher L Kaufman ◽

Joshua W Lampe

Keyword(s):

Blood Flow ◽

Chest Compression ◽

Detrimental Effect ◽

Perfusion Pressure ◽

Vena Cava ◽

Coronary Perfusion Pressure ◽

Right Atrial ◽

Coronary Perfusion ◽

Chest Compressions ◽

Over Time

Introduction: Guidelines for treatment of cardiac arrest recommend minimizing interruptions in chest compressions based on research indicating that interruptions compromise coronary perfusion pressure (CPP) and blood flow and reducing the likelihood of successful defibrillation. We investigated the dynamics of CPP before, during, and after compression interruptions and how they change over time. Methods: CPR was performed on domestic swine (~30 Kg) using standard physiological monitoring. Blood flow was measured in the abdominal aorta (AAo), the inferior vena cava, the right common carotid and external jugular. Ventricular fibrillation (VF) was electrically induced. Mechanical chest compressions (CC) were started after four minutes of VF. CC were delivered at a rate of 100 compressions per minute (cpm) and at a depth of 2” for a total of 12 min. CPP was calculated as the difference between aortic and right atrial pressure at end-diastole per Utstein guidelines. CPP was determined for 5 compressions prior to the interruption, every 2 seconds during the CC interruption, and for 7 compressions after the interruption. Per protocol, 12 interruptions occurred at randomized time points. Results: Across 12 minutes of CPR, averaged CPP prior to interruption was significantly greater than the averaged CPP after the interruption (22.4±1.0 vs. 15.5±0.73 mmHg). As CPR continued throughout the 12 minutes, CPP during compressions decreased (First 6 min = 24.1±1.4 vs. Last 6 min = 20.1±1.3 mmHg, p=0.05), but the effect of interruptions remained constant resulting in a 20% drop in CPP for every 2 seconds irrespective of the prior CPP. The increase (slope) of CPP after resumption of compressions was significantly reduced over time (First 6 min = 1.47±0.18 vs. Last 6 min = 0.82±0.13 mmHg/compression). Conclusions: Chest compression interruptions have a detrimental effect on coronary perfusion and blood flow. The magnitude of this effect increases over time as a resuscitation effort continues. These data confirm the importance of providing uninterrupted CPR particularly in long duration resuscitations.

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Abstract 20: Peripheral Intravenous Analysis Detects Return of Spontaneous Circulation Without Interruption of Chest Compressions in a Rat Model of Cardiopulmonary Resuscitation

Circulation ◽

10.1161/circ.140.suppl_2.20 ◽

2019 ◽

Vol 140 (Suppl_2) ◽

Author(s):

Claudius Balzer ◽

Franz J Baudenbacher ◽

Antonio Hernandez ◽

Michele M Salzman ◽

Matthias L Riess ◽

...

Keyword(s):

Mechanical Ventilation ◽

Cardiopulmonary Resuscitation ◽

Chest Compression ◽

Venous Pressure ◽

Fold Increase ◽

Spontaneous Circulation ◽

Arterial Line ◽

Chest Compressions ◽

Waveform Data ◽

Return Of Spontaneous Circulation

Introduction: A higher chest compression fraction (CCF) or percentage of time providing chest compressions is associated with improved survival after cardiac arrest (CA). Pauses in chest compression duration during cardiopulmonary resuscitation (CPR) to palpate a pulse can reduce the CCF. Peripheral Intravenous Analysis (PIVA) is a novel method for determining cardiac and volume status using waveforms from a standard peripheral intravenous (IV) line. We hypothesize that PIVA will demonstrate the onset of return of spontaneous circulation (ROSC) without interruption of CPR. Methods: Eight Zucker Diabetic Fatty (ZDF) rats (4 lean, 4 diabetic) were intubated, ventilated, and cannulated with a 24g IV in the tail vein and a 22g IV in the femoral artery, each connected to a TruWave pressure transducer. Mechanical ventilation was discontinued to achieve CA. After 8 minutes, CPR began with mechanical ventilation, IV epinephrine, and chest compressions using 1.5 cm at 200 times per minute until mean arterial pressure (MAP) increased to 120 mmHg per arterial line. All waveforms were recorded and analyzed in LabChart. PIVA was measured using a Fourier transform of the peripheral venous waveform. Data are mean ± SD. Statistics: Unpaired student’s t-test (two-tailed), α = 05. Results: CA and ROSC were achieved in all 8 rats. Within 1 minute of CPR, there was a 70 ± 35 fold increase/decrease in PIVA during CPR that was temporally associated with ROSC. Within 8 ± 13 seconds of a reduction in PIVA, there was a rapid increase in end-tidal CO 2 . In all rats, ROSC occurred within 38 ± 9 seconds of the maximum PIVA value. Peripheral venous pressure decreased by 1.2 ± 0.9 mmHg during resuscitation and ROSC, which was not significant different at p=0.05. Conclusion: In this pilot study, PIVA detected ROSC without interrupting CPR. Use of PIVA may obviate the need pause CPR for pulse checks, and may result in a higher CCF and survival. Future studies will focus on PIVA and CPR efficacy.

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A Chest Compression Quality Evaluation Using Mechanical Chest Compressions under Different Working Situations in the Ambulance

International Journal of Clinical Medicine ◽

10.4236/ijcm.2015.68071 ◽

2015 ◽

Vol 06 (08) ◽

pp. 530-537

Author(s):

Pär Lindblad ◽

Annika Åström Victorén ◽

Christer Axelsson ◽

Bjarne Madsen Härdig

Keyword(s):

Chest Compression ◽

Quality Evaluation ◽

Chest Compressions

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An alternative method of chest compression from over-the-head during cardiopulmonary resuscitation

10.21203/rs.2.11675/v1 ◽

2019 ◽

Author(s):

Michał Ćwiertnia ◽

Marek Kawecki ◽

Tomasz Ilczak ◽

Monika Mikulska ◽

Mieczyslaw Dutka ◽

...

Keyword(s):

Cardiopulmonary Resuscitation ◽

Chest Compression ◽

Artificial Respiration ◽

Hand Position ◽

Chest Compressions ◽

Confined Spaces ◽

Medical Response ◽

Emergency Interventions ◽

The Subject

Abstract Background Maintaining highly effective cardiopulmonary resuscitation (CPR) can be particularly difficult when artificial respiration using a bag-valve-mask device, combined with chest compression have to be carried out by one person. The aim of the study is to compare the quality of CPR conducted by one paramedic using chest compression from the patient’s side, with compression carried out from behind the patient’s head. Methods The subject of the study were two methods of CPR – ‘standard’ (STD) and ‘over-the-head’ (OTH). The STD method consisted of 30 chest compressions from the patient’s side, and two attempts at artificial respiration after moving round to behind the patient’s head. In the OTH method, both compression and respiration were conducted from behind the patient’s head. Results Both CPR methods were conducted by 38 paramedics working in medical response teams. The average time of the interruptions between compression cycles (STD 9.184 s, OTH 7.316 s, p<0.001); the depth of compression 50–60 mm (STD 50.65%, OTH 60.22%, p<0.001); the rate of compression 100–120/min. (STD 46.39%, OTH 53.78%, p<0.001); complete chest wall recoil (STD 84.54%, OTH 91.46%, p<0.001); correct hand position (STD 99.32%, OTH method 99.66%, p<0.001). The remaining parameters showed no significant differences in comparison to reference values. Conclusions The demonstrated higher quality of CPR in the simulated research using the OTH method conducted by one person justifies the use of this method in a wider range of emergency interventions than only for CPR conducted in confined spaces.

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Abstract 122: Compression-Induced Ventilation Volumes Decrease with Chest Compression Depth and Prolonged CPR

Circulation ◽

10.1161/circ.130.suppl_2.122 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Simone Ordelman ◽

Paul Aelen ◽

Paul van Berkom ◽

Gerrit J Noordergraaf

Keyword(s):

Gas Exchange ◽

Endotracheal Tube ◽

Chest Compression ◽

Minute Ventilation ◽

Time Effect ◽

Chest Compressions ◽

Initial Value ◽

Compression Depth ◽

Minute Period ◽

Over Time

Introduction: Compression-induced ventilation may aid gas exchange during CPR. We hypothesized that the amount of gas moving in and out of the lungs depends on chest compression depth. Methods: VF was induced in five female, anesthetized and intubated pigs of about 30 kg. After 30 seconds of non-intervention time, chest compressions were started and maintained at a rate of 100 compressions per minute. Every two minutes chest compression depth was altered, resulting in 14 minutes of CPR with a depth sequence of 4 cm, 3 cm, 4 cm, 5 cm, 5.5 cm, 5 cm and 4 cm. Ventilations were performed manually with a bag-valve device 10 times per minute during continuous chest compressions by a dedicated expert. Airway flow was measured at the end of the endotracheal tube. Compression-induced ventilation was determined from the periods between the manual ventilations. The average compression-induced minute ventilation volume was determined over the last minute of each two minute period of CPR at each specific chest compression depth. Results: The compression-induced ventilation volume in the first period of CPR at 4 cm of depth was 1.6 ± 0.9 L/min (about 4% of total ventilation volume). The figure shows how the compression-induced ventilation volume decreases with increasing chest compression depth, relative to this initial value. CPR with a chest compression depth of 4 cm was performed three times in each pig, and the corresponding compression-induced ventilation volumes decreased with time. This suggested that there might be just a time effect (e.g. atelectasis). However, the final compression depth of 4 cm resulted in larger compression-induced ventilation volumes than the preceding 5 cm and 5.5 cm compression depths, indicating that the decreased volume over time could not purely be a time effect, but must also be an effect of the depth. Conclusion: In conclusion, compression-induced ventilation volume appears to decrease with deeper chest compressions as well as with prolonged CPR.

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Abstract 167: Epinephrine Plus Chest Compressions May Be Superior to Epinephrine Alone in a Hypoxia-Induced Porcine Model of Lifeless Shock

Circulation ◽

10.1161/circ.140.suppl_2.167 ◽

2019 ◽

Vol 140 (Suppl_2) ◽

Author(s):

Felipe Teran ◽

Claire Centeno ◽

Alex L Lindqwister ◽

William J Hunckler ◽

William Landis ◽

...

Keyword(s):

Chest Compression ◽

Porcine Model ◽

Contractile Activity ◽

Coronary Perfusion Pressure ◽

Spontaneous Circulation ◽

Swine Model ◽

Coronary Perfusion ◽

Chest Compressions ◽

Fraction Of Inspired Oxygen ◽

External Chest Compressions

Background: Lifeless shock (LS) (previously called EMD and pseudo-PEA) is a global hypotensive ischemic state with retained coordinated myocardial contractile activity and an organized ECG. We have previously described our hypoxic LS model. The role of standard external chest compressions remains unclear in the setting of LS and its associated intrinsic hemodynamics. Although it is known the patients with LS have better prognosis compared to PEA, it is unclear what is the best treatment strategy. Prior work has shown that chest compressions (CC) when synchronized with native systole results in significant hemodynamic improvement, most notably coronary perfusion pressure (CPP), and hence it is plausible that standard dyssynchronous CC may be detrimental to hemodynamics. Furthermore, retrospective clinical data has shown that LS patients treated with vasopressors and no CC, may have better outcomes. We compared epinephrine only versus epinephrine and chest compression, in a porcine model of LS. Methods: Our porcine model of hypoxic LS has previously been described. We randomized pigs to episodes of LS treated with epinephrine only (control) (0.0015 mg/kg) versus epinephrine plus standard external chest compressions (intervention). Animals were endotracheally intubated and mechanically ventilated, and the fraction of inspired oxygen (FiO 2 ) was gradually lowered from room air (20-30% O 2 ) to a target FiO 2 of 3-7% O 2 . This target FiO 2 was maintained until the systolic blood pressure (SBP) dropped to 30 mmHg for 30 seconds, or the animal became bradycardic (HR less than 40), which was defined as the start of LS. FiO 2 was then raised to 100%, and then animal would receive control or intervention. Return of spontaneous circulation (ROSC) was defined as SBP 60 mmHg, stable after 2 minutes. Results: Twenty-six episodes of LS in 11 animals received epinephrine only control and 21 episodes the epinephrine plus chest compression intervention. The rates of ROSC in two minutes or less were 5/26 (19%) in the control arm vs 14/21 (67%) in the intervention arm (P=0.001;95% CI 19.7 %-67.2%). Conclusions: In a swine model of hypoxia induced LS, epinephrine plus CPR may be superior to epinephrine alone.

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Abstract 133: Electrical Insulating Gloves for Safe Hands-on Defibrillation Do Not Compromise the Quality of Chest Compressions

Circulation ◽

10.1161/circ.130.suppl_2.133 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Jakob E Thomsen ◽

Martin Harpsø ◽

Graham W Petley ◽

Svend Vittinghus ◽

Charles D Deakin ◽

...

Keyword(s):

Clinical Examination ◽

Chest Compression ◽

Electrical Insulation ◽

Compression Rate ◽

Chest Compressions ◽

Compression Depth ◽

Resuscitation Guidelines ◽

Hands On ◽

Class 1

Introduction: We have recently shown that Class 1 electrical insulating gloves are safe for hands-on defibrillation. Continuous chest compressions during defibrillation reduce the peri-shock pauses and increase the subsequent chance of successful defibrillation. In this study we have investigated the effect of these electrical insulation gloves on the quality of chest compressions, compared with normal clinical examination gloves. Methods: Emergency medical technicians trained in 2010 resuscitation guidelines delivered uninterrupted chest compressions for 6 min on a manikin, whilst wearing Class 1 electrical insulating gloves or clinical examination gloves. The order of gloves was randomized and each session of chest compressions was separated by at least 30 min to avoid fatigue. Data were collected from the manikin. Compression depth and compression rate were compared. Results: Data from 35 participants are shown in Figure 1. There was no statistically significant difference between Class 1 electrical insulating gloves in chest compression depth (median±range: 45 (28-61) vs 43 (28-61) p=0.69) and chest compression rate (113 (67-150) vs 113(72-145), p=0.87) when compared to clinical examination cloves. Conclusion: These preliminary data suggest that the use of Class 1 electrical insulation gloves does not reduce the quality of chest compressions during simulated CPR compared to clinical examination gloves.

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Abstract 2019: Untrained Volunteers Perform High Quality CPR When using an Automatic External Defibrillator with a CPR Voice Prompting Algorithm

Circulation ◽

10.1161/circ.116.suppl_16.ii_437 ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Benjamin S Abella ◽

Salem Kim ◽

Alexandra Colombus ◽

Cheryl L Shea ◽

Lance B Becker

Keyword(s):

Real Time ◽

Patient Outcomes ◽

Chest Compression ◽

Automatic External Defibrillator ◽

Chest Compressions ◽

High Quality ◽

Cpr Training ◽

Adult Volunteers ◽

Improve Patient ◽

External Defibrillator

Background: Recent investigations have demonstrated that CPR performance among trained providers can be improved by audiovisual prompting and real-time feedback, and higher quality CPR before defibrillation can improve shock success and has the potential to improve patient outcomes. Objective: We hypothesized that simplified voice prompts incorporated into an automatic external defibrillator (AED) can lead to improvements in CPR performance by untrained lay rescuers. Methods: Adult volunteers with no prior CPR training were assessed in their use of an AED with chest compression voice instructions and metronome prompts on a CPR-recording manikin. Volunteers were given minimal instructions regarding use of the device and were given no instructions regarding CPR performance. The AED was designed to prompt five cycles of 30 chest compressions between defibrillatory attempts. Chest compression rates and depths were measured via review of videotape and manikin recording data, respectively. Results: A total of 60 adults were assessed in their use of the AED, with a mean age of 33.6±12.8; 36/63 (57%) were female. Mean chest compression rate was 103±12 and mean depth was 37±14 mm. Furthermore, minimal decay in chest compression rates occurred over 5 cycles of chest compressions, with mean rate of 101±19 during the first cycle and 104±10 during the 5 th cycle. No volunteers were unable to use the AED or complete 5 cycles of chest compressions. Conclusions: Our work demonstrates that with appropriate real-time prompts delivered even in the absence of training or human coaching, laypersons can perform CPR that has a quality often similar to trained providers. This finding has important implications for AED design especially in light of the renewed importance of both CPR and the interaction of quality chest compressions and defibrillatory success.

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Abstract 325: Resuscitation Practices in Pediatric Hospitals: Insights From Get with the Guidelines-Resuscitation

Circulation ◽

10.1161/circ.142.suppl_4.325 ◽

2020 ◽

Vol 142 (Suppl_4) ◽

Author(s):

Jesse L Chan ◽

Yuanyuan Tang ◽

Joan S Roberts ◽

Paul S Chan

Keyword(s):

Chest Compression ◽

Pediatric Patients ◽

National Registry ◽

Chest Compressions ◽

Free Standing ◽

Pediatric Hospitals ◽

Adults And Children ◽

Get With The Guidelines ◽

Mock Codes ◽

Hospital Cardiac Arrest

Background: Resuscitation practices for adult in-hospital cardiac arrest (IHCA) vary widely, based on setting and size. Resuscitation practices in pediatric hospitals have not been examined in detail, and whether practices differ between free-standing pediatric hospitals and combined hospitals (which care for adults and children) is unknown. Methods: We conducted a survey of U.S. hospitals that submit data on pediatric IHCA to GWTG-Resuscitation, a large national registry of IHCA, to elicit detailed information on resuscitation practices. Hospitals were categorized as free-standing pediatric hospitals and combined hospitals, and rates of resuscitation practices were compared. Results: A total of 33 hospitals with at least 5 IHCA events between 2015-2019 completed the survey, of which 9 (27.3%) were freestanding pediatric hospitals and 24 (72.7%) were combined hospitals. Overall, 18 (54.5%) hospitals used a device to measure chest compression quality, 2 (6.1%) used a mechanical device to deliver chest compressions, 6 (18.2%) routinely monitored diastolic pressures during resuscitations, 16 (48.5%) had a staff member monitor chest compression quality, 10 (30.3%) used lanyards or hats to designate leaders during a resuscitation, 16 (48.5%) routinely conducted immediate code debriefings, and 7 (21.2%) conducted mock codes at least quarterly and 17 (51.5%) reported no set schedule. Freestanding pediatric hospitals were more likely to employ a device to measure chest compressions (88.9% vs. 41.7%; P=0.016), conduct code debriefing always or frequently after resuscitations (77.8% vs. 37.5%, P=0.044), use lanyards or a hat to designate the code team leader during resuscitations (66.7% vs. 16.7%, P=0.006), and allow nurses to defibrillate using an AED (77.8% vs. 29.2%, P=0.01). There were no differences in simulation frequency or other resuscitation practices between the 2 hospital groups. Conclusions: Across hospitals caring for pediatric patients, substantial variation exists in resuscitation practices. For some resuscitation practices, there were differences between freestanding pediatric hospitals and hospitals which care for both adults and children.

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