The impact of increased chest compression fraction on survival for out-of-hospital cardiac arrest patients with a non-shockable initial rhythm

Out-of-Hospital Cardiac Arrest

Survival from out-of-hospital cardiac arrest (OHCA) is predicated on a community and system-wide approach that includes rapid recognition of cardiac arrest, capable bystander CPR, effective basic and advanced life support (BLS and ALS) by EMS providers, and coordinated postresuscitation care. Management of these critically ill patients continues to evolve. This article focuses on the management of OHCA by EMS providers.

High Variability in the Duration of Chest Compression Interruption is Associated With Poor Outcomes in Pediatric Extracorporeal Cardiopulmonary Resuscitation

OBJECTIVES

To determine the association between chest compression interruption (CCI) patterns and outcomes in pediatric patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR).

DESIGN

Cardiopulmonary resuscitation (CPR) data were collected using defibrillator-electrode and bedside monitor waveforms from pediatric ECPR cases between 2013 and 2021. Duration and variability of CCI during cannulation for ECPR was determined and compared with survival to discharge using Fishers exact test and logistic regressions with cluster-robust se s for adjusted analyses.

SETTING

Quaternary care children's hospital.

PATIENTS

Pediatric patients undergoing ECPR.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 41 ECPR events, median age was 0.7 years (Q1, Q3: 0.1, 5.4), 37% (15/41) survived to hospital discharge with 73% (11/15) of survivors having a favorable neurologic outcome. Median duration of CPR from start of ECPR cannulation procedure to initiation of extracorporeal membrane oxygenation (ECMO) flow was 21 minutes (18, 30). Median duration of no-flow times associated with CCI during ECMO cannulation was 11 seconds (5, 28). Following planned adjustment for known confounders, survival to discharge was inversely associated with maximum duration of CCI (odds ratio [OR] 0.91 [0.86-0.95], p = 0.04) as well as the variability in the CCI duration (OR 0.96 [0.93-0.99], p = 0.04). Cases with both above-average CCI duration and higher CCI variability ( sd > 30 s) were associated with lowest survival (12% vs. 54%, p = 0.009). Interaction modeling suggests that lower variability in CCI is associated with improved survival, especially in cases where average CCI durations are higher.

CONCLUSIONS

Shorter duration of CCI and lower variability in CCI during cannulation for ECPR were associated with survival following refractory pediatric cardiac arrest.

Bag-Valve-Mask Ventilation and Survival From Out-of-Hospital Cardiac Arrest: A Multicenter Study

BACKGROUND

Few studies have measured ventilation during early cardiopulmonary resuscitation (CPR) before advanced airway placement. Resuscitation guidelines recommend pauses after every 30 chest compressions to deliver ventilations. The effectiveness of bag-valve-mask ventilation delivered during the pause in chest compressions is unknown. We sought to determine: (1) the incidence of lung inflation with bag-valve-mask ventilation during 30:2 CPR; and (2) the association of ventilation with outcomes after out-of-hospital cardiac arrest.

METHODS

We studied patients with out-of-hospital cardiac arrest from 6 sites of the Resuscitation Outcomes Consortium CCC study (Trial of Continuous Compressions versus Standard CPR in Patients with Out-of-Hospital Cardiac Arrest). We analyzed patients assigned to the 30:2 CPR arm with ≥2 minutes of thoracic bioimpedance signal recorded with a cardiac defibrillator/monitor. Detectable ventilation waveforms were defined as having a bioimpedance amplitude ≥0.5 Ω (corresponding to ≥250 mL VT) and a duration ≥1 s. We defined a chest compression pause as a 3- to 15-s break in chest compressions. We compared the incidence of ventilation and outcomes in 2 groups: patients with ventilation waveforms in <50% of pauses (group 1) versus those with waveforms in ≥50% of pauses (group 2).

RESULTS

Among 1976 patients, the mean age was 65 years; 66% were male. From the start of chest compressions until advanced airway placement, mean±SD duration of 30:2 CPR was 9.8±4.9 minutes. During this period, we identified 26 861 pauses in chest compressions; 60% of patients had ventilation waveforms in <50% of pauses (group 1, n=1177), and 40% had waveforms in ≥50% of pauses (group 2, n=799). Group 1 had a median of 12 pauses and 2 ventilations per patient versus group 2, which had 12 pauses and 12 ventilations per patient. Group 2 had higher rates of prehospital return of spontaneous circulation (40.7% versus 25.2%; P<0.0001), survival to hospital discharge (13.5% versus 4.1%; P<0.0001), and survival with favorable neurological outcome (10.6% versus 2.4%; P<0.0001). These associations persisted after adjustment for confounders.

CONCLUSIONS

In this study, lung inflation occurred infrequently with bag-valve-mask ventilation during 30:2 CPR. Lung inflation in ≥50% of pauses was associated with improved return of spontaneous circulation, survival, and survival with favorable neurological outcome.

Residual Psychomotor Skills of Orderlies After a Novel Chest Compression Training Intervention

BACKGROUND

High-quality chest compressions are essential to favorable patient outcomes after in-hospital cardiac arrest. Without frequent training, however, skill in performing compressions declines considerably. The Timely Chest Compression Training (T-CCT) intervention was introduced in 2019 as a quality improvement initiative to address this problem. The long-term impact of the T-CCT is unknown.

METHODS

A cohort study was conducted at a university-affiliated hospital in Quebec, Canada. Chest compression performance among orderlies was measured by using a subtractive scoring model and mannequins. The association of exposure to the T-CCT 10 months earlier with having an excellent chest compression performance (score ≥90 out of 100), after adjusting for potential confounders, was examined.

RESULTS

A total of 412 orderlies participated in the study. More than half (n = 232, 56%) had been exposed to the T-CCT, and the rest (n = 180, 44%) had not. Nearly half (n = 106, 46%) of orderlies exposed to the T-CCT had an excellent performance, compared with less than one-third (n = 53, 30%) of nonexposed orderlies. In univariable analysis, previous exposure to the T-CCT was associated with 1.53 times greater risk of having an excellent performance (risk ratio, 1.53; 95% CI, 1.17-1.99). This effect remained after adjustment for potential confounders (risk ratio, 1.57; 95% CI, 1.19-2.07).

CONCLUSION

The results of this study suggest that the T-CCT has a lasting effect on the psychomotor skills of orderlies 10 months after initial exposure. Further research should investigate the impact of the intervention on patient outcomes after in-hospital cardiac arrest.

Out-of-Hospital Cardiac Arrest

Survival from out-of-hospital cardiac arrest (OHCA) is predicated on a community and system-wide approach that includes rapid recognition of cardiac arrest, capable bystander CPR, effective basic and advanced life support (BLS and ALS) by EMS providers, and coordinated postresuscitation care. Management of these critically ill patients continues to evolve. This article focuses on the management of OHCA by EMS providers.

Methods for calculating ventilation rates during resuscitation from out-of-hospital cardiac arrest

OBJECTIVE

Ventilation control is important during resuscitation from out-of-hospital cardiac arrest (OHCA). We compared different methods for calculating ventilation rates (VR) during OHCA.

METHODS

We analyzed data from the Pragmatic Airway Resuscitation Trial, identifying ventilations through capnogram recordings. We determined VR by: 1) counting the number of breaths within a time epoch ("counted" VR), and 2) calculating the mean of the inverse of measured time between breaths within a time epoch ("measured" VR). We repeated the VR estimates using different time epochs (10, 20, 30, 60 sec). We defined hypo- and hyperventilation as VR <6 and >12 breaths/min, respectively. We assessed differences in estimated hypo- and hyperventilation with each VR measurement technique.

RESULTS

Of 3,004 patients, data were available for 1,010. With the counted method, total hypoventilation increased with longer time epochs ([10-s epoch: 75 sec hypoventilation] to [60-s epoch: 97 sec hypoventilation]). However, with the measured method, total hypoventilation decreased with longer time epochs ([10-s epoch: 223 sec hypoventilation] to [60-s epoch: 150 sec hypoventilation]). With the counted method, the total duration of hyperventilation decreased with longer time epochs ([10-s epochs: 35 sec hyperventilation] to [60-s epoch: 0 sec hyperventilation]). With the measured method, total hyperventilation decreased with longer time epochs ([10-s epoch: 78 sec hyperventilation] to [60-s epoch: 0 sec hyperventilation]). Differences between the measured and counted estimates were smallest with a 60-s time epoch.

CONCLUSIONS

Quantifications of hypo- and hyperventilation vary with the applied measurement methods. Measurement methods are important when characterizing ventilation rates in OHCA.

Impact of Ultrasonography on Chest Compression Fraction and Survival in Patients with Out-of-hospital Cardiac Arrest

INTRODUCTION

Whether ultrasonography (US) contributes to delays in chest compressions and hence a negative impact on survival is uncertain. In this study we aimed to investigate the impact of US on chest compression fraction (CCF) and patient survival.

METHODS

We retrospectively analyzed video recordings of the resuscitation process in a convenience sample of adult patients with non-traumatic, out-of-hospital cardiac arrest. Patients receiving US once or more during resuscitation were categorized as the US group, while the patients who did not receive US were categorized as the non-US group. The primary outcome was CCF, and the secondary outcomes were the rates of return of spontaneous circulation (ROSC), survival to admission and discharge, and survival to discharge with a favorable neurological outcome between the two groups. We also evaluated the individual pause duration and the percentage of prolonged pauses associated with US.

RESULTS

A total of 236 patients with 3,386 pauses were included. Of these patients, 190 received US and 284 pauses were related to US. Longer resuscitation duration was observed in the US group (median, 30.3 vs 9.7 minutes, P<.001). The US group had comparable CCF (93.0% vs 94.3%, P=0.29) with the non-US group. Although the non-US group had a better rate of ROSC (36% vs 52%, P=0.04), the rates of survival to admission (36% vs 48%, P=0.13), survival to discharge (11% vs 15%, P=0.37), and survival with favorable neurological outcome (5% vs 9%, P=0.23) did not differ between the two groups. The pause duration of pulse checks with US was longer than pulse checks alone (median, 8 vs 6 seconds, P=0.02). The percentage of prolonged pauses was similar between the two groups (16% vs 14%, P=0.49).

CONCLUSION

When compared to the non-ultrasound group, patients receiving US had comparable chest compression fractions and rates of survival to admission and discharge, and survival to discharge with a favorable neurological outcome. The individual pause was lengthened related to US. However, patients without US had a shorter resuscitation duration and a better rate of ROSC. The trend toward poorer results in the US group was possibly due to confounding variables and nonprobability sampling. It should be better investigated in further randomized studies.

2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimizing pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.

2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimizing pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.

Impact of Two Resuscitation Sequences on Alveolar Ventilation during the First Minute of Simulated Pediatric Cardiac Arrest: Randomized Cross-Over Trial

The International Liaison Committee on Resuscitation regularly publishes a Consensus on Science with Treatment Recommendations, but guidelines can nevertheless differ when knowledge gaps persist. In case of pediatric cardiac arrest, the American Heart Association recommends following the adult resuscitation sequence, i.e., starting with chest compressions. Conversely, the European Resuscitation Council advocates the delivery of five initial rescue breaths before starting chest compressions. This was a superiority, randomized cross-over trial designed to determine the impact of these two resuscitation sequences on alveolar ventilation in a pediatric model of cardiac arrest. The primary outcome was alveolar ventilation during the first minute of resuscitation maneuvers according to the guidelines used. A total of 56 resuscitation sequences were recorded (four sequences per team of two participants). The ERC approach enabled higher alveolar ventilation volumes (370 mL [203−472] versus 276 mL [140−360], p < 0.001) at the cost of lower chest compression fractions (57% [54;64] vs. 66% [59;68], p < 0.001). Although statistically significant, the differences found in this simulation study may not be clinically relevant. Therefore, and because of the importance of overcoming barriers to resuscitation, advocating a pediatric-specific resuscitation algorithm may not be an appropriate strategy.

2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimising pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.

Compromised cardiopulmonary resuscitation quality due to regurgitation during endotracheal intubation: a randomised crossover manikin simulation study

Background

Regurgitation is a complication common during cardiopulmonary resuscitation (CPR). This manikin study evaluated the effect of regurgitation during endotracheal intubation on CPR quality.

Methods

An airway-CPR manikin was modified to regurgitate simulated gastric contents into the oropharynx during chest compression during CPR. In total, 54 emergency medical technician-paramedics were assigned to either an oropharyngeal regurgitation or clean airway scenario and then switched to the other scenario after finishing the first. The primary outcomes were CPR quality metrics, including chest compression fraction (CCF), chest compression depth, chest compression rate, and longest interruption time. The secondary outcomes were intubation success rate and intubation time.

Results

During the first CPR–intubation sequence, the oropharyngeal regurgitation scenario was associated with a significantly lower CCF (79.6% vs. 85.1%, P < 0.001), compression depth (5.2 vs. 5.4 cm, P < 0.001), and first-pass success rate (35.2% vs. 79.6%, P < 0.001) and greater longest interruption duration (4.0 vs. 3.0 s, P < 0.001) than the clean airway scenario. During the second and third sequences, no significant difference was observed in the CPR quality metrics between the two scenarios. In the oropharyngeal regurgitation scenario, successful intubation was independently and significantly associated with compression depth (hazard ratio = 0.47, 95% confidence interval, 0.24–0.91), whereas none of the CPR quality metrics were related to successful intubation in the clean airway scenario.

Conclusion

Regurgitation during endotracheal intubation significantly reduces CPR quality.

Trial registration

ClinicalTrials.gov, NCT05278923, March 14, 2022.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-022-00662-0.

Airway Strategy and Ventilation Rates in the Pragmatic Airway Resuscitation Trial

BACKGROUND

We sought to describe ventilation rates during out-of-hospital cardiac arrest (OHCA) resuscitation and their associations with airway management strategy and outcomes.

METHODS

We analyzed continuous end-tidal carbon dioxide capnography data from adult OHCA enrolled in the Pragmatic Airway Resuscitation Trial (PART). Using automated signal processing techniques, we determined continuous ventilation rate for consecutive 10-second epochs after airway insertion. We defined hypoventilation as a ventilation rate <6 breaths/min. We defined hyperventilation as a ventilation rate >12 breaths/min. We compared differences in total and percentage post-airway hyper- and hypoventilation between airway interventions (laryngeal tube (LT) vs. endotracheal intubation (ETI). We also determined associations between hypo-/hyperventilation and OHCA outcomes (ROSC, 72-hour survival, hospital survival, hospital survival with favorable neurologic status).

RESULTS

Adequate post-airway capnography were available for 1,010 (LT n=714, ETI n=296) of 3,004 patients. Median ventilation rates were: LT 8.0 (IQR 6.5-9.6) breaths/min, ETI 7.9 (6.5-9.7) breaths/min. Total duration and percentage of post-airway time with hypoventilation were similar between LT and ETI: median 1.8 vs. 1.7 minutes, p=0.94; median 10.5% vs. 11.5%, p=0.60. Total duration and percentage of post-airway time with hyperventilation were similar between LT and ETI: median 0.4 vs. 0.4 minutes, p=0.91; median 2.1% vs. 1.9%, p=0.99. Hypo- and hyperventilation exhibited limited associations with OHCA outcomes.

CONCLUSION

In the PART Trial, EMS personnel delivered post-airway ventilations at rates satisfying international guidelines, with only limited hypo- or hyperventilation. Hypo- and hyperventilation durations did not differ between airway management strategy and exhibited uncertain associations with OCHA outcomes.

A Multicenter, Prospective Study Comparing Subxiphoid and Parasternal Views During Brief Echocardiography: Effect on Image Quality, Acquisition Time, and Visualized Anatomy

BACKGROUND

Recent literature has suggested echocardiography (echo) may prolong pauses in chest compressions during cardiac arrest.

OBJECTVES

We sought to determine the impact of the sonographic approach (subxiphoid [SX] vs. parasternal long [PSL]) on time to image completion, image quality, and visualization of cardiac anatomy during echo, as performed during Advanced Cardiac Life Support.

METHODS

This was a multicenter, randomized controlled trial conducted at 29 emergency departments (EDs) assessing the time to image acquisition and image quality between SX and PSL views for echo. Patients were enrolled in the ED and imaged in a simulated cardiac arrest scenario. Clinicians experienced in echo performed both SX and PSL views, first view in random order. Image quality and time to image acquisition were recorded. Echos were evaluated for identification of cardiac landmarks. Data are presented as percentages or medians with interquartile ranges (IQRs).

RESULTS

We obtained 6247 echo images, comprising 3124 SX views and 3123 PSL. Overall time to image acquisition was 9.0 s (IQR 6.7-14.1 s). Image acquisition was shorter using PSL (8.8 s, IQR 6.5-13.5 s) compared with SX (9.3 s, IQR 6.7-15.0 s). The image quality was better with the PSL view (3.86 vs. 3.54; p < 0.0001), twice as many SX images scoring in the worst quality category compared with PSL (8.6% vs. 3.7%). Imaging of the pericardium, cardiac chambers, and other anatomic landmarks was superior with PSL imaging.

CONCLUSIONS

Echo was performed in < 10 s in > 50% of patients using either imaging technique. Imaging using PSL demonstrated improved image quality and improved identification of cardiac landmarks.

Chest Compression Fraction Alone Does Not Adequately Measure Cardiopulmonary Resuscitation Quality in Out-of-Hospital Cardiac Arrest

BACKGROUND

High-quality cardiopulmonary resuscitation in out-of-hospital cardiac arrest is important for increased survival and improved neurological outcome. Chest compression fraction measures the proportion of time chest compressions are given during a cardiac arrest resuscitation. Chest compression fraction has not been compared with the quality of chest compressions delivered at the recommended rate and depth of 100-120/min and 2.0-2.4 inches, respectively.

OBJECTIVES

We evaluate whether chest compression fraction correlates with compressions at a target rate of 100-120/min and depth of 2.0-2.4 inches in chest diameter.

METHODS

A prospective, observational study design was used to compare chest compression fraction to compressions in target in out-of-hospital cardiac arrest patients in a prehospital urban setting. We include all adult, non-traumatic out-of-hospital cardiac arrest patients with a resuscitation attempt during January 1, 2019 through September 30, 2019, for a total of 9 months. Spearman's rank correlation was used to determine correlation between compression fraction and compressions in target.

RESULTS

A total of 120 out-of-hospital cardiac arrest cases were included in the study. We found a high chest compression fraction median of 83% (interquartile range 72-90%), but a low compression in target median of 13% (interquartile range 5-29%). There was no significant correlation between chest compression fraction and compressions in target when analyzed linearly (Spearman's Rho = 0.165, p = 0.072). No difference was found when dichotomizing chest compression fraction into high and low variables in comparison with compressions in target (14% vs. 10%, p = 0.119).

CONCLUSION

Chest compression fraction is not associated with compressions in target for rate and depth for out-of-hospital cardiac arrest cardiopulmonary resuscitation.

Effect of Early Supraglottic Airway Device Insertion on Chest Compression Fraction during Simulated Out-of-Hospital Cardiac Arrest: Randomised Controlled Trial

Early insertion of a supraglottic airway (SGA) device could improve chest compression fraction by allowing providers to perform continuous chest compressions or by shortening the interruptions needed to deliver ventilations. SGA devices do not require the same expertise as endotracheal intubation. This study aimed to determine whether the immediate insertion of an i-gel^® while providing continuous chest compressions with asynchronous ventilations could generate higher CCFs than the standard 30:2 approach using a face-mask in a simulation of out-of-hospital cardiac arrest. A multicentre, parallel, randomised, superiority, simulation study was carried out. The primary outcome was the difference in CCF during the first two minutes of resuscitation. Overall and per-cycle CCF quality of compressions and ventilations parameters were also compared. Among thirteen teams of two participants, the early insertion of an i-gel^® resulted in higher CCFs during the first two minutes (89.0% vs. 83.6%, p = 0.001). Overall and per-cycle CCF were consistently higher in the i-gel^® group, even after the 30:2 alternation had been resumed. In the i-gel^® group, ventilation parameters were enhanced, but compressions were significantly shallower (4.6 cm vs. 5.2 cm, p = 0.007). This latter issue must be addressed before clinical trials can be considered.

Outcomes of Out-of-hospital Cardiac Arrests After a Decade of System-wide Initiatives Optimising Community Chain of Survival in Taipei City

OBJECTIVE

A strengthened chain of survival benefits patient outcomes after out-of-hospital cardiac arrest (OHCA).² Over the past decade, the Taipei Fire Department (TFD) has continuously implemented system-wide initiatives on this issue.We hypothesised that for adult, non-trauma OHCA patients, the bundle of these system-wide initiatives are associated with better outcomes.

METHODS

We conducted a registry-based, retrospective study to examine the association between consecutive system-level initiatives and OHCA survival on a two-yearly basis using trend analysis and multivariable logistic regression. The primary outcome was survival to hospital discharge (STHD) and favourable neurological status.

RESULTS

We analysed 18,076 cases from 2008 to 2017. The numbers of two-yearly cases of OHCA with resuscitation attempts from 2008 to 2017 were 3,576, 3,456, 3,822, 3,811, and 3,411. There was a significant trend of improved STHD (Two-fold) and favourable neurological outcome (Six-fold) over the past decade. Similar trends were observed in the shockable and non-shockable groups. Considering the first 2 years as baseline, the odds of STHD and favourable neurological status in the end of the initiatives increased significantly after adjusting for universally recognised predictors for OHCA survival.

CONCLUSION

For non-trauma adult OHCA in Taipei, continuous, multifaceted system-wide initiatives on the community chain of survival were associated with improved odds of STHD and favourable neurologic outcomes.

Quality of Cardiopulmonary Resuscitation and 5-Year Survival Following in-Hospital Cardiac Arrest

Purpose

To improve cardiac arrest survival, international resuscitation guidelines emphasize measuring the quality of cardiopulmonary resuscitation (CPR). We aimed to investigate CPR quality during in-hospital cardiac arrest (IHCA) and study long-term survival outcomes.

Patients and Methods

This was a cohort study of IHCA from December 2011 until November 2014. Data were collected from the hospital switch board, patient records, and from defibrillators. Impedance data from defibrillators were analyzed manually at the level of single compressions. Long-term survival at 1-, 3-, and 5 years is reported.

Results

The study included 189 IHCAs; median (interquartile range (IQR)) time to first rhythm analysis was 116 (70-201) seconds and median (IQR) time to first defibrillation was 133 (82-264) seconds. Median (IQR) chest compression rate was 126 (119-131) per minute and chest compression fraction (CCF) was 78% (69-86). Thirty-day survival was 25%, while 1-year-, 3-year-, and 5-year survival were 21%, 14%, and 13%, respectively. There was no significant association between any survival outcomes and CCF, whereas chest compression rate was associated with survival to 30 days and 3 years. Overall, 5-year survival was associated with younger age (median 68 vs 74 years, p=0.003), less comorbidity (Charlson comorbidity index median 3 vs 5, p<0.001), and witnessed cardiac arrest (96% vs 77%, p=0.03).

Conclusion

We established a systematic collection of IHCA CPR quality data to measure and improve CPR quality and long-term survival outcomes. Median time to first rhythm check/defibrillation was <3 minutes, but median chest compression rate was too fast and median CCF slightly below 80%. More than half of 30-day survivors were still alive at 5 years.

Methodology and framework for the analysis of cardiopulmonary resuscitation quality in large and heterogeneous cardiac arrest datasets

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) data debriefing and clinical research often require the retrospective analysis of large datasets containing defibrillator files from different vendors and clinical annotations by the emergency medical services.

AIM

To introduce and evaluate a methodology to automatically extract cardiopulmonary resuscitation (CPR) quality data in a uniform and systematic way from OHCA datasets from multiple heterogeneous sources.

METHODS

A dataset of 2236 OHCA cases from multiple defibrillator models and manufacturers was analyzed. Chest compressions were automatically identified using the thoracic impedance and compression depth signals. Device event time-stamps and clinical annotations were used to set the start and end of the analysis interval, and to identify periods with spontaneous circulation. A manual audit of the automatic annotations was conducted and used as gold standard. Chest compression fraction (CCF), rate (CCR) and interruption ratio were computed as CPR quality variables. The unsigned error between the automated procedure and the gold standard was calculated.

RESULTS

Full-episode median errors below 2% in CCF, 1 min^-1 in CCR, and 1.5% in interruption ratio, were measured for all signals and devices. The proportion of cases with large errors (>10% in CCF and interruption ratio, and >10 min^-1 in CCR) was below 10%. Errors were lower for shorter sub-intervals of interest, like the airway insertion interval.

CONCLUSIONS

An automated methodology was validated to accurately compute CPR metrics in large and heterogeneous OHCA datasets. Automated processing of defibrillator files and the associated clinical annotations enables the aggregation and analysis of CPR data from multiple sources.

Assessment of chest compression interruptions during advanced cardiac life support

AIM

To identify potentially avoidable factors responsible for chest compression interruptions and to evaluate the influence of chest compression fraction on achieving return of spontaneous circulation and survival to hospital discharge.

METHODS

In this prospective observational study, each resuscitation managed by mobile medical teams from August 1st, 2016, to August 1st, 2018 was video recorded using a body-mounted GoPro camera. The duration of all chest compression interruptions was recorded and chest compression fraction was calculated. All actions causing an interruption of at least 10 s were analyzed.

RESULTS

Two hundred and six resuscitations of both in- and out-of-hospital cardiac arrest patients were analysed. In total 1867 chest compression interruptions were identified. Of these, 623 were longer than 10 s in which a total of 794 actions were performed. In 4.3% of the registered pauses, cardiopulmonary resuscitation was interrupted for more than 60 s. The most performed actions during prolonged interruptions were rhythm/pulse checks (51.6%), installation/use of mechanical chest compression devices (11.1%), cardiopulmonary resuscitation provider switches (6.7%) and ETT placements (6.2%). No statistically significant relationship was found between chest compression fraction and return of spontaneous circulation or survival.

CONCLUSION

The majority of chest compression interruptions during resuscitation were caused by prolonged rhythm checks, cardiopulmonary resuscitation provider switches, incorrect use of mechanical chest compression devices and ETT placement. No association was found between chest compression fraction and return of spontaneous circulation, nor an influence on survival. This was presumably caused by the high baseline chest compression fraction of >86%.

Effect on Chest Compression Fraction of Continuous Manual Compressions with Asynchronous Ventilations Using an i-gel® versus 30:2 Approach during Simulated Out-of-Hospital Cardiac Arrest: Protocol for a Manikin Multicenter Randomized Controlled Trial

The optimal airway management strategy during cardiopulmonary resuscitation is uncertain. In the case of out-of-hospital cardiac arrest, a high chest compression fraction is paramount to obtain the return of spontaneous circulation and improve survival and neurological outcomes. To improve this fraction, providing continuous chest compressions should be more effective than using the conventional 30:2 ratio. Airway management should, however, be adapted, since face-mask ventilation can hardly be carried out while continuous compressions are administered. The early insertion of a supraglottic device could therefore improve the chest compression fraction by allowing ventilation while maintaining compressions. This is a protocol for a multicenter, parallel, randomized simulation study. Depending on randomization, each team made up of paramedics and emergency medical technicians will manage the 10-min scenario according either to the standard approach (30 compressions with two face-mask ventilations) or to the experimental approach (continuous manual compressions with early insertion of an i-gel® supraglottic device to deliver asynchronous ventilations). The primary outcome will be the chest compression fraction during the first two minutes of cardiopulmonary resuscitation. Secondary outcomes will be chest compression fraction (per cycle and overall), compressions and ventilations quality, time to first shock and to first ventilation, user satisfaction, and providers' self-assessed cognitive load.