Chest compression-only vs standard CPR in adults with out-of-hospital cardiac arrest (OHCA): Cardiac and neurological outcomes.

Resuscitative cesarean delivery: prioritizing team preparedness for one of the most challenging obstetric emergencies.

Introduction: Neurological injury significantly contributes to poor outcomes after return of spontaneous circulation (ROSC) following cardiac arrest (CA). Prior in vitro studies showed that hypothermia promotes VDAC3 ubiquitination, reducing microglial apoptosis under ischemia/reperfusion (I/R) conditions. This study explored the in vivo role of the E3 ubiquitin ligase HECTD1 in mediating VDAC3 degradation and neuroprotection during therapeutic hypothermia. Methods: Adult male Sprague–Dawley rats underwent 8 minutes of asphyxial CA followed by standardized cardiopulmonary resuscitation (CPR). Rats were randomized into normothermia (T37, core temperature 37 ± 0.5°C) and hypothermia (T33, 33 ± 0.5°C) groups, initiated 5 minutes post-ROSC and maintained for 6 hours. Each temperature group was subdivided into PBS control, si-NC (non-targeting siRNA), and si-Hectd1 subgroups. The si-Hectd1 group received intracerebroventricular injection of adeno-associated virus encoding Hectd1-targeting siRNA. Survival was monitored for 72 hours. Neurological function were assessed at 72 hours after ROSC, including neurological deficit score (NDS), serum S100B and NSE levels, and histopathological evaluation (H&E, electron microscopy). Apoptosis-related protein expression (VDAC3, cleaved caspase-3, BAX, BCL-2) was measured by western blot. HECTD1–VDAC3 interaction and colocalization were analyzed via co-immunoprecipitation and immunofluorescence. Results: Hypothermia significantly improved 72-hour survival and neurological outcomes compared to normothermia. The T33 group demonstrated reduced expression of VDAC3, cleaved caspase-3, and BAX, and increased HECTD1 and BCL-2 levels (p < 0.05). Hypothermia enhanced the interaction between HECTD1 and VDAC3 and promoted VDAC3 ubiquitination, which were abrogated by Hectd1 knockdown. The T37+si-Hectd1 subgroup exhibited the worse survival and neurological outcomes. No significant differences were observed between PBS and si-NC subgroups at either temperature. Conclusions: Therapeutic hypothermia mitigates brain injury following CA/CPR by promoting HECTD1-dependent VDAC3 degradation and suppressing apoptosis.These findings suggest a novel molecular mechanism underlying hypothermic neuroprotection and identify HECTD1 as a potential therapeutic target.

Transthoracic echocardiography is superior to AHA guidelines location in identifying the left ventricle for chest compressions.

With the emergence of long-duration space travel, space exploration missions pose a major concern due to the heightened risk of medical emergencies, such as sudden cardiac arrest. While several cardiopulmonary resuscitation (CPR) methods have been proposed for human spaceflight, their reliability and effectiveness remain uncertain, as these methods lack systematic evaluation through physiological metrics. To address this gap, a high-fidelity CPR simulator was developed to simulate blood circulation and deliver real-time hemodynamic feedback. Herein, we show that in normogravity, the CPR simulator generates compression-decompression waveforms that align with published animal and test bench studies. As an exploratory comparison, we also report relative differences in hemodynamic pressure observed between normogravity and hypogravity conditions. The findings highlight that internal physiological responses are critical for evaluating CPR effectiveness in hypogravity, with the CPR simulator serving as a plausible tool. The current study represents an initial step toward the validation of a gold standard CPR protocol and may contribute to the complex health challenges surrounding long-duration spaceflight.

Survival and Neurologic Performance at 30 Days and Beyond Following Out-of-Hospital Cardiac Arrest Comparing Standard Cardiopulmonary Resuscitation Versus Chest Compression-Only Resuscitation by Bystanders: A Systematic Review and Meta-Analysis.

To determine whether high-resolution (HighRes) and multimodal integration of physiologic signals improve prediction of return of spontaneous circulation (ROSC) during pediatric cardiopulmonary resuscitation (CPR) compared with low-resolution (LowRes) and single-modality approaches. Retrospective analysis of experimental data using machine learning models for outcome prediction. Laboratory setting with pediatric swine models of cardiac arrest. A total of 187 pediatric swine undergoing standardized cardiac arrest and CPR protocols. Animals were monitored using multiple physiologic signals during CPR, including aortic blood pressure (ABP), right atrial pressure (RAP), capnography, and electrocardiography. No therapeutic interventions were evaluated. Four data approaches were evaluated: 1) Waveform-HighRes (100 Hz waveforms); 2) Compression-HighRes (compression-by-compression physiologic series); 3) Waveform-LowRes (15-s averaged waveforms); and 4) Compression-LowRes (15-s averaged compression-by-compression series). Models were developed to predict ROSC using segments 2-4, 2-6, 2-8, and 2-10 minutes of CPR, using both single and combined signal modalities. Area under the receiver operating characteristic curve (AUROC) was used to evaluate models' performance. In early CPR (2-4 min), Compression-HighRes outperformed both LowRes approaches for ABP (AUROC, 0.74 [0.65-0.82] vs. 0.65 [0.55-0.74] and 0.54 [0.44-0.64]) and RAP (0.70 [0.62-0.79] vs. 0.61 [0.51-0.70] and 0.57 [0.48-0.66]; p < 0.05). In multimodal models, LowRes data performed comparably to HighRes models (AUROC, 0.76-0.79). Across time points, ABP-based model performance improved, reaching AUROC 0.90 (0.84-0.95) for the full CPR period (2-10 min)-comparable to the multimodal model (0.89 [0.83-0.95]). HighRes monitoring improved early ROSC prediction for individual signals, especially ABP and RAP. However, combining multiple modalities compensates for lower resolution, enabling comparable predictive performance. These findings support data-driven strategies for selecting physiologic targets and technical requirements in physiology-directed CPR.

A musical metronome is one method to assist the public in performing optimal chest compressions. This study evaluated the influence of innovative downbeat Fit-cardiopulmonary resuscitation (CPR) music versus no music on guiding laypersons to perform high-quality CPR. A randomised controlled trial was conducted among non-medical undergraduate students in Klang Valley, comparing a Fit-CPR music group (intervention) to standard CPR training (control). The intervention group received 90 minutes of hands-only CPR training, including a lecture, video presentation and three rounds of CPR practice with facilitators while listening to music. The control group underwent the same training without music. Primary outcomes included chest compression-associated components (rate, depth, recoil) and non-compression components (safety, response, help, breathing check, hand placement). A total of 53 students participated, with 27 (50.9%) in the intervention and 26 (49.1%) in the control group. Both groups showed significant improvement post-training (p &lt; 0.001). The intervention group outperformed the control in compression and non-compression components (p = 0.008, p = 0.031). A significant association was found between the intervention and compression rate (p &lt; 0.001), with 96.3% achieving the target rate compared to 53.8% in the control. However, no significant association was found for compression depth or recoil (p = 1.000, p = 0.498). This study demonstrates that Fit-CPR music helps laypersons to sustain the American Heart Association-recommended chest compression rate, highlighting its potential as an effective CPR training aid.

Bag-valve-endotracheal ventilation vs mechanical ventilation during cardiopulmonary resuscitation: a randomized experimental porcine study

Limb compression is proposed as a supplement to cardiopulmonary resuscitation (CPR) because it has the potential to increase central organ blood flow rates. This is significant because CPR only has a survival rate of 10-15%, and survival depends on the amount of blood flow generated during CPR. However, the underlying physiological mechanisms are not understood, thereby limiting optimal application of limb compression during CPR. Therefore, this study addressed the hypothesis that circuit pathway reduction, volume displacement, and wave reflection mechanisms contribute to higher central organ blood flow rates. Mathematical models were utilized because modeling is the only way to isolate physiological mechanisms. This study utilized two validated mathematical models that were minimally altered to investigate limb compression during CPR. A lumped-parameter model addressed circuit pathway reduction and volume displacement while the other model isolated wave reflections. Relative to standard CPR, the model simulating circuit pathway reduction via CPR with tourniquets predicted increases of cerebral and coronary flow rates by 3% each while the model simulating volume displacement via CPR with constant pressure cuffs predicted increased cerebral and coronary flow rates by up to 74% and 109%, respectively. Furthermore, the wave reflection model predicted increases in blood flow rates of major cerebral arteries up to 11% and across all major abdominal arteries up to 27%. All limb compression configurations and modalities resulted in increased predicted central organ blood flow rates with volume displacement, wave reflection, and circuit pathway reduction mechanisms, in that order, being most influential.

Small animal models are indispensable in cardiopulmonary resuscitation (CPR) research. High-quality CPR, characterized by consistent chest compression rate, depth, and positioning is crucial for survival. However, achieving standardization in manual high-frequency chest compressions in small animal models remains technically challenging. This study evaluated the reproducibility of manual chest compressions and introduced a novel mechanical chest compression device (MCD) designed to improve consistency in rodent experiments. In an in vitro setup, manual compressions were performed by ten participants at target rates ranging from 100 to 260 bpm, guided by a metronome. Compressions performed on a fluid-filled polymer reservoir were analyzed for the compression rate, variability, and time within a ± 10% target range. A color indicator was used to assess the variability of the compression point. A small animal MCD was designed and tested under the same conditions. In vivo, 5 Sprague-Dawley rats underwent 5 min of electrically induced normothermic cardiac arrest followed by 8 min of external chest compressions using the MCD. Obtained data was compared to the in vitro results. A total of 21,650 manual and 20,098 mechanical compressions were analyzed. At 200 bpm, chest compressions using the MCD were significantly more precise (201 ± 1.2 bpm) than manual compressions (218 ± 21 bpm, p < 0.001) with a significant reduced compression point variability (1.7 ± 0.1 cm2 vs. 10.8 ± 3.1 cm2, p < 0.001). Manual compressions maintained target rate in 58.8% of time compared to 100% for the MCD. In vivo testing confirmed these findings with chest compressions remaining within the target range 100% of the time and showing minimal rate variability (1.8 ± 1.7 bpm). These results highlight the limitations of manual chest compressions and demonstrate the potential of the MCD to enhance standardization and reproducibility in rodent CPR research.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-31959-2.

Refractory ventricular fibrillation, which fails to respond to defibrillation, is associated with poor survival. Despite this, there are no treatments that are proven effective beyond standard defibrillation and cardiopulmonary resuscitation. Double sequential external defibrillation (DSED) has been proposed as an alternative defibrillation strategy for this patient population. In this review, we will discuss key evidence surrounding DSED, as we present two opposing arguments, 'pro' that DSED is ready for clinical practice and 'con' that more research is needed prior to implementation of this technique. The Double Sequential External Defibrillation for Refractory Ventricular Fibrillation (DOSE VF) randomized clinical trial demonstrated improved patient outcomes for patients with refractory ventricular fibrillation who did not respond to standard defibrillation attempts. There remain unanswered questions with respect to the mechanism by which DSED may improve outcomes and the logistics of implementation into clinical practice. This article discusses some of the key controversies surrounding DSED and whether this novel defibrillation strategy is ready for integration into standard practice. Further research is ongoing that may help to answer further questions related to the utility of DSED.

Cardiopulmonary Resuscitation (CPR) is a vital lifesaving intervention for cardiac arrest. The systematic review is to investigate CPR knowledge, attitude, self-efficacy, and influencing factors among health professionals. This review analyzed cross-sectional studies published from 2019 to 2024 using data sources from PubMed, Scopus, and Google Scholar. The result revealed a good knowledge ranging from 11.9% to 89.5%. Approximately 65.0% had positive attitudes, and 89.4% positive self-efficacy. Affecting factors include age, work experience, CPR training, specialty area, and exposure to cardiac arrest cases. The findings highlight the importance of standardized and frequent CPR training, leading to improved quality of care.

Active abdominal compression-decompression resuscitation (AACD-CPR) has been proposed as an alternative to standard cardiopulmonary resuscitation (STD-CPR) for cases of multiple rib fractures with asphyxial cardiac arrest (CA), yet its underlying hemodynamic effects remain unclear. In this study, thirty-eight rats underwent bilateral rib fracture modeling, with thirty successfully modeled and then randomly assigned to the AACD-CPR, STD-CPR, or sham groups (n = 10 each). After surgical procedures, rats experienced 8min of asphyxia followed by assigned CPR, or no intervention in the sham group. Hemodynamic and arterial blood gas parameters were measured at multiple time points during and after resuscitation, and rates of return of spontaneous circulation (ROSC) as well as cumulative 240-minute survival were recorded. AACD-CPR resulted in lower right atrial diastolic pressure during resuscitation and less severe acidosis at 30min post-resuscitation compared to STD-CPR, although other hemodynamic and outcome measures did not differ significantly between the two resuscitation techniques. These findings suggest that AACD-CPR can achieve similar hemodynamic performance and survival outcomes to STD-CPR in a rat model of multiple rib fractures causing asphyxial cardiac arrest, supporting its potential as an alternative when conventional chest compressions are compromised.

Abstract Introduction Improving emergency protocols during space missions is a topic of current interest with the upcoming long-lasting missions and the advent of space tourism (1–3). In the unique environment of spaceflight, cardiac arrest is a particularly challenging emergency as both the rescuer and the patient are floating due to microgravity, thus requiring the development of specific positions to provide efficient chest compression during cardiopulmonary resuscitation (CPR). As recommended by international guidelines (4), the Hand-Stand method is the current gold standard CPR method since it achieves the best compression depth and rate (5) but necessitates specific training to be accurately performed. Here, we postulated that automatic chest compression devices (ACCDs) routinely used on Earth by physicians facing cardiac arrests, particularly in hostile environments or during refractory (i.e. sustained) cardiac arrests(6-8), could improve CPR in microgravity. We aimed to compare ACCDs versus manual CPR in weightlessness simulated through parabolic flights. Methods This prospective, open, controlled study compared CPR performed by 3 ACCDs (one standard mechanical piston device, one compression band device, and one small-sized piston device) to manual CPR during a CNES (Centre National d’Etudes Spatiales, the French space agency) parabolic flights campaign onboard a modified A310 aircraft turned into a flying laboratory. This setup could re-create accurate microgravity, during the free falling phases of parabolic flight. Chest compression depths and rates were monitored by a high fidelity CPR training manikin. Results (presented as median [IQR]) The standard piston device had a median compression depth of 53.0 [53.0 - 54.0] mm, significantly higher than the other two devices, and than Manual CPR (Handstand method), measured at 29.0 [26.0 - 32.0] mm, 29.0 [27.5 - 30.7] mm and 34.5 [29.6 - 43.3] mm, respectively (p value &amp;lt;0.001). Compression rates were 101 [101 - 101], 100 [100 - 100] and 80 [80 - 80] compressions per minute (cpm) for the standard piston device, compression band device, and small sized piston device, respectively. Manual CPR provided a significantly higher compression rate with 115 [109 - 123] cpm (p value &amp;lt;0.001). Conclusion Manual CPR remains undereffective under Zero Gravity and ACCDs, especially the standard piston device (i.e., the only experimental group reproducing CPR matching with international guidelines), should be considered in emergency procedures to manage cardiac arrest in microgravity. Other keystones of cardiac arrest management should also be translated to the spaceflight environment, such as early defibrillation or emergency drug administration if required (epinephrine), as these are already described in the NASA emergency protocols for the International Space Station.Visual abstract

Background: Interposed abdominal compression cardiopulmonary resuscitation (IAC-CPR) has been proposed as a novel approach to augment forward blood flow and improve resuscitation outcomes in cardiac arrest. However, its clinical efficacy and hemodynamic advantages compared to standard CPR remain incompletely defined. Objective: To assess the impact of IAC-CPR versus standard CPR on hemodynamic parameters and clinically meaningful outcomes in adult patients undergoing resuscitation. Methods: A systematic review and meta-analysis was conducted adhering to PRISMA guidelines. Outcomes assessed included return of spontaneous circulation (ROSC), survival to hospital discharge, favorable neurological recovery (CPC 1–2), and hemodynamic parameters: mean arterial pressure (MAP), end-tidal CO2 (ETCO2), and CPR duration. Meta-analyses were performed using random-effects models with Hedges’ g or odds ratios (OR) where appropriate. Heterogeneity was evaluated via I2 and τ2 statistics. Results: 11 studies with a combined total of 1,025 patients (IAC: 581; Standard: 444) was included. ROSC was significantly higher in the IAC group (OR = 1.78, 95% CI [1.16, 2.74]; p = 0.014; I2 = 27.5%). Survival to discharge showed a trend favoring IAC (OR = 2.09, 95% CI [0.74, 5.88]; p = 0.092). Favorable neurological outcome (CPC 1–2) was significantly improved with IAC (OR = 3.34, 95% CI [1.67, 6.66]; p = 0.017). MAP was significantly higher with IAC-CPR (SMD = 1.62, 95% CI [1.47, 1.78]; p &lt; 0.001). ETCO2 was significantly elevated in IAC (SMD = 1.31, 95% CI [1.10, 1.53]; p &lt; 0.001). CPR duration was shorter in IAC (SMD = –0.12, 95% CI [–0.19, –0.05]; p = 0.006). There was minimal statistical heterogeneity in most outcomes (I2 = 0% for MAP, ETCO2, CPC, and duration). Conclusions: IAC-CPR significantly improves hemodynamic variables and is associated with better ROSC and favorable neurological outcomes compared to standard CPR. While survival to discharge showed a favorable trend, further high-quality RCTs are warranted to confirm long-term benefits. IAC-CPR may represent a promising adjunctive strategy during advanced cardiac life support.

Background: Limb compression is commonly used in medicine to address many physiological and pathological conditions. Limb compression is also proposed as a supplement to cardiopulmonary resuscitation (CPR) because it has the potential to increase central organ blood flows. This is significant since CPR only has a survival rate of 10-15%, and survival depends on the amount of blood flow generated during CPR. However, the underlying physiological mechanisms are not understood, thereby limiting application of limb compression during CPR. Hypothesis: Circuit pathway reduction and volume displacement are limb compression mechanisms that contribute to higher central organ blood flows during CPR. Methods: This study utilized a modified but previously validated lumped-parameter mathematical model (Figure 1, Halperin et al., Annals of Biomedical Engineering 1987) that isolated the effects of circuit pathway reduction and volume displacement. Briefly, CPR was simulated by applying extramural pressure to the compartments of the thorax via a sine wave at 60 Hz with a duty cycle of 0.40 and a maximum of 100 mmHg. Circuit pathway reduction via tourniquets was simulated by increasing arterial and venous resistances (R17 and R19, respectively) of the limbs. Volume displacement via cuffs was modeled by applying constant (100 mmHg) or cyclic extramural pressure to the arterial and venous compartments (C17 and C18) of the limbs. Limb and chest compression waveforms were the same but 180° out-of-phase from one another. All models simulated 90 seconds of CPR, and flows were taken as the time-averaged flow throughout the last three cycles. Results: Relative to standard CPR (Figure 2, orange), tourniquets (Figure 2, red) were predicted to increase cerebral and coronary flows by 3%. Simulations involving constantly inflated cuffs (Figure 2, blue) forecasted cerebral and coronary blood flow increases of 74 and 109%, respectively, as compared to standard CPR. Cyclic counterpulsation cuffs (Figure 2, black) were predicted to increase cerebral and coronary blood flows by 40 and 67%, respectively, relative to standard CPR. All limb compression modalities resulted in increased predicted abdominal blood flows and decreased cardiac outputs and venous returns, compared to standard CPR. Conclusion: Limb compression during CPR, via circuit pathway reduction and volume displacement mechanisms, is predicted to contribute to higher central organ blood flows, which could increase survival.

Background: Out-of-hospital cardiac arrests (OHCAs) are a major public health concern worldwide. Early cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use have significantly improved survival outcomes. Police officers are often the first to arrive at the OHCA scene of and play a critical role in early intervention. In 2024, the New Taipei City Police Department launched a Police AED Program in collaboration with the Fire Department. Despite this initiative, concerns remain regarding officer preparedness and willingness to perform CPR and use AEDs when dispatched. Methods: A cross-sectional survey was conducted from January to December 2024 among 4,867 frontline police officers who received standardized CPR and AED training (15-minute lecture and 45-minute hands-on session). Before training, a 33-item validated questionnaire assessing demographics, knowledge, confidence, legal awareness, and willingness to be dispatched was completed. After excluding incomplete responses, 3,744 valid questionnaires (76.9%) were analyzed. Cronbach's alpha was 0.81. Statistical analyses included chi-square, Fisher’s exact tests, and stepwise logistic regression, with subgroup analysis by age and years of service quartiles. This study was approved by the Institutional Review Board of Far Eastern Memorial Hospital (Approval No. 112212-E). Results: Among the 3,744 respondents, 2,785 (74.4%) were willing to be dispatched for CPR and AED use. Officers aged 28–32 showed higher willingness than those ≤27 (OR = 1.29, 95% CI: 1.01–1.63, p = 0.038), while those with 4–7 years of service were less willing than those with ≤4 years (OR = 0.67, 95% CI: 0.54–0.84, p &lt; 0.001). No significant differences were found in older groups. Barriers included legal concerns and low confidence, with younger officers citing workload and preference to help known individuals. Key facilitators were training, legal protection, and incentives, with patterns varying by age and experience. Conclusion: Our study revealed that most frontline officers were willing to be dispatched to perform CPR and to use AEDs; however, barriers such as legal concerns and low self-confidence persist. Tailored interventions such as legal protection, skill-focused training, and age-appropriate incentives are recommended to enhance police participation in prehospital resuscitation efforts.

Comparison of Outcomes between Standard Cardiopulmonary Resuscitation (S-CPR) and Over-the-Head Cardiopulmonary Resuscitation (OTH-CPR): A Systematic Review and Meta-Analysis.

Combined end-tidal CO2 and diastolic blood pressure-guided CPR improves survival from cardiac arrest in porcine model.