Prediction of blood pressure using chest compression waveform during cardiopulmonary resuscitation.

OBJECTIVES: This study aimed to predict blood pressure during CPR using chest compression waveform information obtained from a CPR feedback device. METHODS: Quantitative data including chest compression waveforms from a CPR feedback device and the blood pressure measured by arterial cannulation in patients with cardiac arrest during CPR were used. Forty-one features to predict blood pressure were selected from chest compression waveform and demographic characteristics with neighborhood component analysis algorithm. Optimized Gaussian process regression was used as a machine learning algorithm. RESULTS: A total of 14,619 datasets from 19 patients with cardiac arrest (mean age: 66 ± 13 years, 14 men) were used in the analysis. The model could predict blood pressure with high precision and low bias for almost the whole range of systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP). The correlation coefficients (r) between the predicted and actual values were 0.954 (95% confidence interval: 0.951-0.957, p < 0.001) for SBP, 0.926 (95% confidence interval: 0.921-0.931, p < 0.001) for DBP, and 0.958 (95% confidence interval: 0.955-0.961, p < 0.001) for MBP, which all indicated a very good agreement. CONCLUSIONS: Blood pressure generated by chest compressions can be predicted with high accuracy by a machine learning method using chest compression waveform information obtained from a CPR feedback device and the patient's demographic characteristics. Real-time provision of the predicted blood pressure can be used to monitor the quality and efficacy of CPR.

Vitamin D deficiency as a risk factor for sudden cardiac arrest: A multicenter case-control study.

BACKGROUND AND AIMS: Vitamin D is known to influence the risk of cardiovascular disease, which is a recognized risk factor for sudden cardiac arrest (SCA). However, the relationship between vitamin D and SCA is not well understood. Therefore, this study aims to investigate the association between vitamin D and SCA in out-of-hospital cardiac arrest (OHCA) patients compared to healthy controls. METHODS AND RESULTS: Using the Phase II Cardiac Arrest Pursuit Trial with Unique Registration and Epidemiologic Surveillance (CAPTURES II) registry, a 1:1 propensity score-matched case-control study was conducted between 2017 and 2020. Serum 25-hydroxyvitamin D (vitamin D) levels in patients with OHCA (454 cases) and healthy controls (454 cases) were compared after matching for age, sex, cardiovascular risk factors, and lifestyle behaviors. The mean vitamin D levels were 14.5 ± 7.6 and 21.3 ± 8.3 ng/mL among SCA cases and controls, respectively. Logistic regression analysis was used adjusting for cardiovascular risk factors, lifestyle behaviors, corrected serum calcium levels, and estimated glomerular filtration rate (eGRF). The adjusted odds ratio (aOR) for vitamin D was 0.89 (95% confidence interval [CI] 0.87-0.91). The dose-response relationship demonstrated that vitamin D deficiency was associated with SCA incidence (severe deficiency, aOR 10.87, 95% CI 4.82-24.54; moderate deficiency, aOR 2.24, 95% CI 1.20-4.20). CONCLUSION: Vitamin D deficiency was independently and strongly associated with an increased risk of SCA, irrespective of cardiovascular and lifestyle factors, corrected calcium levels, and eGFR.

The Magnitude of Change in Serum Phosphate Concentration Is Associated with Mortality in Patients with Severe Trauma.

PURPOSE: Previous studies have suggested that serum phosphate concentration is a prognostic factor in critically ill patients. However, the association between changes in serum phosphate levels and prognosis of patients with trauma remains unclear. MATERIALS AND METHODS: This study included patients with severe trauma who were treated at the emergency department. Delta phosphate (Δ phosphate) was defined as the difference between serum phosphate concentrations measured at baseline and after 24 hours from the initial measurement. Patients were divided into five groups according to their Δ phosphate levels: group I (Δ phosphate <-2 mg/dL), group II (Δ phosphate -2 to -0.5 mg/dL), group III (Δ phosphate -0.5 to 0.5 mg/dL), group IV (Δ phosphate 0.5 to 2 mg/dL), and group V (Δ phosphate ≥2 mg/dL). RESULTS: Overall, 1905 patients with severe trauma were included in the analysis. The 30-day mortality was the lowest in group III and tended to increase in groups with a larger Δ phosphate in both the positive and negative directions (group I: 13.7%, group II: 6.8%, group III: 4.6%, group IV: 6.6%, and group V: 26.8%). In multivariable analysis with group III as the reference group, the odds ratios (ORs) of mortality were statistically significant in group IV [OR, 1.92; 95% confidence interval (CI), 1.05-3.56] and group V (OR, 5.28; 95% CI, 2.47-11.24). CONCLUSION: An increase in serum phosphate concentrations 24 hours after the initial measurement could be considered as an independent prognostic factor in patients with severe trauma.

Hemodynamic Effect of Repeated Epinephrine Doses Decreases With Cardiopulmonary Resuscitation Cycle Progression.

BACKGROUND: Epinephrine is administered to increase coronary perfusion pressure during advanced life support and promote short-term survival. Recent cardiopulmonary resuscitation (CPR) guidelines recommend an epinephrine dosing interval of 3 to 5 minutes during resuscitation; however, scientific evidence supporting this recommendation is lacking. Therefore, we aimed to investigate the hemodynamic effects of repeated epinephrine doses during CPR by monitoring augmented blood pressure after its administration in a swine model of cardiac arrest. METHODS AND RESULTS: A secondary analysis of data from a published study was performed using a swine cardiac arrest model. The epinephrine dose was fixed at 1 mg, and the first dose of epinephrine was administered after no-flow and low-flow times of 2 minutes and 8 minutes, respectively, and subsequently administered every 4 minutes. Four cycles of dosing intervals were defined because a previous study was terminated 26 minutes after the induction of ventricular fibrillation. Augmented blood pressures and corresponding timelines were determined. Augmented blood pressure trends following cycles and the epinephrine effect duration were also monitored. Among the 140 CPR cycles, the augmented blood pressure after epinephrine administration was the highest during the first cycle of CPR and decreased gradually with further cycle repetitions. The epinephrine effect duration did not differ between repeated cycles. The maximum blood pressure was achieved 78 to 97 seconds after epinephrine administration. CONCLUSIONS: Hemodynamic augmentation with repeated epinephrine administration during CPR decreased with cycle progression. Further studies are required to develop an epinephrine administration strategy to maintain its hemodynamic effects during prolonged resuscitation.

End-tidal carbon dioxide after sodium bicarbonate infusion during mechanical ventilation or ongoing cardiopulmonary resuscitation.

PURPOSE: End-tidal CO2 is used to monitor the ventilation status or hemodynamic efficacy during mechanical ventilation or cardiopulmonary resuscitation (CPR), and it may be affected by various factors including sodium bicarbonate administration. This study investigated changes in end-tidal CO2 after sodium bicarbonate administration. MATERIALS AND METHODS: This single-center, prospective observational study included adult patients who received sodium bicarbonate during mechanical ventilation or CPR. End-tidal CO2 elevation was defined as an increase of ≥20% from the baseline end-tidal CO2 value. The time to initial increase (lag time, Tlag), time to peak (Tpeak), and duration of the end-tidal CO2 rise (Tduration) were compared between the patients with spontaneous circulation (SC group) and those with ongoing resuscitation (CPR group). RESULTS: Thirty-three patients, (SC group, n = 25; CPR group, n = 8), were included. Compared with the baseline value, the median values of peak end-tidal CO2 after sodium bicarbonate injection increased by 100% (from 21 to 41 mmHg) in all patients, 89.5% (from 21 to 39 mmHg) in the SC group, and 160.2% (from 15 to 41 mmHg) in the CPR group. The median Tlag was 17 s (IQR: 12-21) and the median Tpeak was 35 s (IQR: 27-52). The median Tduration was 420 s (IQR: 90-639). The median Tlag, Tpeak, and Tduration were not significantly different between the groups. Tduration was associated with the amount of sodium bicarbonate for SC group (correlation coefficient: 0.531, p = 0.006). CONCLUSION: The administration of sodium bicarbonate may lead to a substantial increase in end-tidal CO2 for several minutes in patients with spontaneous circulation and in patients with ongoing CPR. After intravenous administration of sodium bicarbonate, the use of end-tidal CO2 pressure as a physiological indicator may be limited.

Epidemiological Characteristics of a COVID-19 Outbreak in a Psychiatric Hospital in Chung-buk.

This study investigated the causes and risks for infection spread in three psychiatric hospitals in Chung-buk, South Korea, to strategize measures to block transmission and prevent a large-scale epidemic. From December 2020 to January 2021, 358 inpatients of Psychiatric Hospitals A, B, and C were enrolled to identify the epidemiological characteristics of confirmed patients. Epidemic curves and propagation relationships were constructed and a genotype analysis was conducted. The index case inpatient from Hospital A transmitted the infection to patients in Hospitals B and C; the infection was confirmed in 47, 193, and 118 patients in Hospitals A, B, and C, respectively. The patient characteristics hampered communication and the close identification of symptom onset. The incidence rate was 10 (2.9%) among employees and 348 (35.8%) among inpatients. The relative risk was 12.1 (95% CI: 6.6-22.5) times higher among inpatients than employees. Next-generation sequencing confirmed the probable infection source as a genotype identical to that of two different outbreaks, although the infection spread was undetermined. Direct risk factors emerged from patient characteristics, wherein cohort isolation was meaningless due to uncontrolled communication. Indirect risk factors included hospital-specific problems due to external factors (non-patient system deficiencies or employee negligence). Prior inspections, a confirmation of non-infection, and institutional emergent measures are needed.

Efficacy of Cardiopulmonary Resuscitation Using Automatic Compression-Defibrillation Apparatus: An Animal Study and A Manikin-Based Simulation Study.

BACKGROUND: Chest compression and defibrillation are essential components of cardiac arrest treatment. Mechanical chest compression devices (MCCD) and automated external defibrillators (AED) are used separately in clinical practice. We developed an automated compression-defibrillation apparatus (ACDA) that performs mechanical chest compression and automated defibrillation. We investigated the performance of cardiopulmonary resuscitation (CPR) with automatic CPR (A-CPR) compared to that with MCCD and AED (conventional CPR: C-CPR). METHODS: Pigs were randomized into A-CPR or C-CPR groups: The A-CPR group received CPR+ACDA, and the C-CPR group received CPR+MCCD+AED. Hemodynamic parameters, outcomes, and time variables were measured. During a simulation study, healthcare providers performed a basic life support scenario for manikins with an ACDA, MCCD, and AED, and time variables and chest compression parameters were measured. RESULTS: The animals showed no significant in hemodynamic effects, including aortic pressures, coronary perfusion pressure, carotid blood flow, and end-tidal CO2, and resuscitation outcomes between the two groups. In both animal and simulation studies, the time to defibrillation, time to chest compression, and hands-off time were significantly shorter in the A-CPR group than those in the C-CPR group. CONCLUSIONS: CPR using ACDA showed similar hemodynamic effects and resuscitation outcomes as CPR using AED and MCCD separately, with the advantages of a reduction in the time to compression, time to defibrillation, and hands-off time.

Development of an automatic device performing chest compression and external defibrillation: An animal-based pilot study.

BACKGROUND: Automatic chest compression devices (ACCDs) can promote high-quality cardiopulmonary resuscitation (CPR) and are widely used worldwide. Early application of automated external defibrillators (AEDs) along with high-quality CPR is crucial for favorable outcomes in patients with cardiac arrest. Here, we developed an automated CPR (A-CPR) apparatus that combines ACCD and AED and evaluated its performance in a pilot animal-based study. METHODS: Eleven pigs (n = 5, A-CPR group; n = 6, ACCD CPR and AED [conventional CPR (C-CPR)] group) were enrolled in this study. After 2 min observation without any treatment following ventricular fibrillation induction, CPR with a 30:2 compression/ventilation ratio was performed for 6 min, mimicking basic life support (BLS). A-CPR or C-CPR was applied immediately after BLS, and resuscitation including chest compression and defibrillation, was performed following a voice prompt from the A-CPR device or AED. Hemodynamic parameters, including aortic pressure, right atrial pressure, coronary perfusion pressure, carotid blood flow, and end-tidal carbon dioxide, were monitored during resuscitation. Time variables, including time to start rhythm analysis, time to charge, time to defibrillate, and time to subsequent chest compression, were also measured. RESULTS: There were no differences in baseline characteristics, except for arterial carbon dioxide pressure (39 in A-CPR vs. 33 in C-CPR, p = 0.034), between the two groups. There were no differences in hemodynamic parameters between the groups. However, time to charge (28.9 ± 5.6 s, A-CPR group; 47.2 ± 12.4 s, C-CPR group), time to defibrillate (29.1 ± 7.2 s, A-CPR group; 50.5 ± 12.3 s, C-CPR group), and time to subsequent chest compression (32.4 ± 6.3 s, A-CPR group; 56.3 ± 10.7 s, C-CPR group) were shorter in the A-CPR group than in the C-CPR group (p = 0.015, 0.034 and 0.02 respectively). CONCLUSIONS: A-CPR can provide effective chest compressions and defibrillation, thereby shortening the time required for defibrillation.

Development of a Gait Feature-Based Model for Classifying Cognitive Disorders Using a Single Wearable Inertial Sensor.

BACKGROUND AND OBJECTIVES: Gait changes are potential markers of cognitive disorders (CDs). We developed a model for classifying older adults with CD from those with normal cognition using gait speed and variability captured from a wearable inertial sensor and compared its diagnostic performance for CD with that of the model using the Mini-Mental State Examination (MMSE). METHODS: We enrolled community-dwelling older adults with normal gait from the Korean Longitudinal Study on Cognitive Aging and Dementia and measured their gait features using a wearable inertial sensor placed at the center of body mass while they walked on a 14-m long walkway thrice at comfortable paces. We randomly split our entire dataset into the development (80%) and validation (20%) datasets. We developed a model for classifying CD using logistic regression analysis from the development dataset and validated it in the validation dataset. In both datasets, we compared the diagnostic performance of the model with that using the MMSE. We estimated optimal cutoff score of our model using receiver operator characteristic analysis. RESULTS: In total, 595 participants were enrolled, of which 101 of them experienced CD. Our model included both gait speed and temporal gait variability and exhibited good diagnostic performance for classifying CD from normal cognition in both the development (area under the receiver operator characteristic curve [AUC] = 0.788, 95% CI 0.748-0.823, p < 0.001) and validation datasets (AUC = 0.811, 95% CI 0.729-0.877, p < 0.001). Our model showed comparable diagnostic performance for CD with that of the model using the MMSE in both the development (difference in AUC = 0.026, standard error [SE] = 0.043, z statistic = 0.610, p = 0.542) and validation datasets (difference in AUC = 0.070, SE = 0.073, z statistic = 0.956, p = 0.330). The optimal cutoff score of the gait-based model was >-1.56. DISCUSSION: Our gait-based model using a wearable inertial sensor may be a promising diagnostic marker of CD in older adults. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that gait analysis can accurately distinguish older adults with CDs from healthy controls.

Gastric Inflation in Prehospital Cardiopulmonary Resuscitation: Aspiration Pneumonia and Resuscitation Outcomes.

Background: Gastric inflation (GI) can induce gastric regurgitation and subsequent aspiration pneumonia, which can prolong intensive care unit stay. However, it has not been verified in patients with out-of-hospital cardiac arrest (OHCA). This study aimed to investigate the incidence of GI during prehospital resuscitation and its effect on aspiration pneumonia and resuscitation outcomes in patients with out-of-hospital cardiac arrest. Methods: This was a multicenter, retrospective, observational study. Patients with non-traumatic OHCA aged > 19 years who had been admitted to the emergency department were enrolled. Patients who received mouth-to-mouth ventilation during bystander cardiopulmonary resuscitation (CPR) were excluded from the evaluation owing to the possibility of GI following bystander CPR. Patients who experienced cardiac arrest during transportation to the hospital who were treated by the emergency medical service (EMS) personnel, and those with a nasogastric tube at the time of chest or abdominal radiography were also excluded. Radiologists independently reviewed plain chest or abdominal radiographs immediately after resuscitation to identify GI. Chest computed tomography performed within 24 h after return of spontaneous circulation was also reviewed to identify aspiration pneumonia. Results: Of 499 patients included in our analysis, GI occurred in approximately 57% during the prehospital resuscitation process, and its frequency was higher in a bag-valve mask ventilation group (n = 70, 69.3%) than in the chest compression-only cardiopulmonary resuscitation (n = 31, 55.4%), supraglottic airway (n = 180, 53.9%), and endotracheal intubation groups (n = 3, 37.5%) (p = 0.031). GI was inversely associated with initial shockable rhythm (adjusted odds ratio [OR] 0.53; 95% confidence interval [CI]: 0.30-0.94). Aspiration pneumonia was not associated with GI. Survival to hospital discharge and favorable neurologic outcomes were not associated with GI during prehospital resuscitation. Conclusions: GI in patients with OHCA was not associated with the use of different airway management techniques.

Intra-arrest transesophageal echocardiography during cardiopulmonary resuscitation.

Determining the cause of cardiac arrest (CA) and the heart status during CA is crucial for its treatment. Transesophageal echocardiography (TEE) is an imaging method that facilitates close observation of the heart without interfering with cardiopulmonary resuscitation (CPR). Intra-arrest TEE is a point-of-care ultrasound technique that is used during CPR. Intra-arrest TEE is performed to diagnose the cause of CA, determine the presence of cardiac contraction, evaluate the quality of CPR, assist with catheter insertion, and explore the mechanism of blood flow during CPR. The common causes of CA diagnosed using intra-arrest TEE include cardiac tamponade, aortic dissection, pulmonary embolism, and intracardiac thrombus, which can be observed on a few simple image planes at the mid-esophageal and upper esophageal positions. To operate an intra-arrest TEE program, it is necessary to secure a physician who is capable of performing TEE, provide appropriate training, establish implementation protocols, and prepare a plan in collaboration with the CPR team.

Effect of Chitosan Coating for Efficient Encapsulation and Improved Stability under Loading Preparation and Storage Conditions of Bacillus Lipopeptides.

This study aims to evaluate the effect of chitosan coating on the formation and properties of Bacillus cyclic lipopeptide (CLP)-loaded liposomes. A nanoencapsulation strategy for a chitosan-coated liposomal system using lecithin phospholipids for the entrapment of antibiotic CLP prepared from Bacillus subtilis KB21 was developed. The produced chitosan-coated CLP liposome had mean size in the range of 118.47-121.67 nm. Transmission electron microscopy showed the spherical-shaped vesicles. Fourier transform infrared spectroscopy findings indicated the successful coating of the produced CLP-loaded liposomes by the used chitosan. Liposomes coated with 0.2% and 0.5% chitosan concentration decreased the surface tension by 7.3-12.1%, respectively, and increased the CLP content by 15.1-27.0%, respectively, compared to the uncoating liposomes. The coated concentration of chitosan influenced their CLP loading encapsulation efficiency and release kinetics. The physicochemical results of the dynamic light scattering, CLP capture efficiency and long-term storage capacity of nanocapsules increased with chitosan coating concentration. Furthermore, the chitosan-coated liposomes exhibited a significant enhancement in the stability of CLP loading liposomes. These results may suggest the potential application of chitosan-coated liposomes as a carrier of antibiotics in the development of the functional platform.

Diet-related complications according to the timing of enteral nutrition support in patients who recovered from out-of-hospital cardiac arrest: a propensity score matched analysis.

BACKGROUND: A proper nutritional plan for resuscitated patients is important in intensive care; however, specific nutritional guidelines have not yet been established. This study aimed to determine the incidence of diet-related complications that were affected by the timing of enteral nutrition in resuscitated patients after cardiac arrest. METHODS: This retrospective and 1:1 propensity score matching study involved patients who recovered after nontraumatic, out-of-hospital cardiac arrest at a tertiary hospital. Patients were divided into an early nutrition support (ENS) group and a delayed nutrition support (DNS) group according to the nutritional support time within 48 hours after admission. The incidence of major clinical complications was compared between the groups. RESULTS: A total of 46 patients (ENS: 23, DNS: 23) were enrolled in the study. There were no differences in body mass index, comorbidity, and time of cardiopulmonary resuscitation between the two groups. There were 9 patients (ENS: 4, DNS: 5) with aspiration pneumonia; 4 patients (ENS: 2, DNS: 2) with regurgitation; 1 patient (ENS: 0, DNS: 1) with ileus; 21 patients (ENS: 10, DNS: 11) with fever; 13 patients (ENS: 8, DNS: 5) with hypoglycemia; and 20 patients (ENS: 11, DNS: 9) with hyperglycemia. The relative risk of each complication during post-resuscitation care was no different between groups. CONCLUSIONS: There was a similar incidence of diet-related complications during post cardiac arrest care according to the timing of enteral nutrition.

Metformin administration is associated with enhanced response to transarterial chemoembolization for hepatocellular carcinoma in type 2 diabetes patients.

Transarterial chemoembolization (TACE) is often used as a locoregional therapy for early hepatocellular carcinoma (HCC) when local ablation or resection are not feasible, but incomplete response and recurrence are commonly observed. In this study, we sought to determine the association between metformin administration and TACE outcomes for single nodular HCC in patients with type 2 diabetes mellitus (T2DM). The retrospective cohort analysis included 164 T2DM patients with single nodular HCC who underwent TACE as an initial treatment, and 91 were exposed to metformin before and after TACE. Propensity score (PS) matching was used to balance covariates. Logistic regression analysis was used to determine the predictors of tumor response after TACE, and Cox regression analysis assessed independent predictors of local tumor recurrence (LTR) in patients with complete response after TACE. Metformin use was associated with significantly higher objective response rate (ORR) in the overall and PS-matched cohort (79.1% vs. 60.3 and 78.7% vs. 57.5%; p = 0.008 and p = 0.029, respectively). Logistic regression analysis showed that metformin use was an independent predictor of ORR in all and PS-matched patients (odds ratio = 2.65 and 3.06; p = 0.016 and 0.034, respectively). Cox regression analysis showed metformin administration was an independent predictor for lower LTR in all and PS-matched patients (hazard ratio = 0.28 and 0.27; p = 0.001 and 0.007, respectively). Metformin administration is associated with better initial response and lower local recurrence after TACE for single nodular HCC in T2DM.

Incidence and Pattern of Aminotransferase Elevation During Anti-Hypertensive Therapy With Angiotensin-II Receptor Blockers.

BACKGROUND: Angiotensin type II receptor blockers (ARBs) are the most widely used anti-hypertensive drugs. This study aimed to elucidate the likelihood and pattern of ARB-induced liver injury in a hospital-based cohort. METHODS: Data of patients receiving fimasartan (n = 5,543), candesartan (n = 6,406), valsartan (n = 6,040), and losartan (n = 9,126) were retrieved from the clinical data warehouse of two tertiary hospitals. Patients with alanine aminotransferase (ALT) levels > 5 times the upper normal limit were assessed according to the Roussel Uclaf Causality Assessment Method (RUCAM). RESULTS: A total of 27,115 patients were enrolled, including 14,630 (54.0%) men, with a mean age of 64.6 years (standard deviation, 13.6). During 31,717 person-years of ARB therapy, serum ALT levels > 120 IU/L were found in 558 (2.1%) person-years, and levels > 200 IU/L were found in 155 (0.6%) person-years. The incidence of ALT elevation > 120 IU/L per 106 cumulative defined daily doses was 6.6, 3.6, 3.9, and 4.0 in the fimasartan, candesartan, valsartan, and losartan groups, respectively (P = 0.002). An ALT level > 200 IU/L with RUCAM score ≥ 6 was found in 20 patients, suggesting probable drug-induced liver injury for 11 (0.2%) patients receiving fimasartan, five (0.1%) receiving candesartan, four (0.1%) receiving valsartan, and none receiving losartan (P < 0.001). CONCLUSION: Approximately 2% of patients receiving ARB therapy had significant ALT elevation (4.24/106 cumulative defined daily doses [cDDDs]), which was associated with probable ARB-related liver injury in 0.07% of patients (0.15/106 cDDDs). Elevation of ALT was more commonly associated with fimasartan than the other ARBs. Clinicians should be aware of the possibility of ARB-related ALT elevation in patients with unexplained chronic abnormal ALT.

Right-to-Left Shunts Occur During Cardiopulmonary Resuscitation: Echocardiographic Observations.

OBJECTIVES: A significant proportion of the population has a patent foramen ovale (PFO). The intracardiac pressure during cardiopulmonary resuscitation (CPR) may differ from that of normal circulation, which may result in a right-to-left shunt in the presence of a PFO. In this study, transesophageal echocardiography (TEE) was conducted to evaluate whether CPR carried out in patients after cardiac arrest causes right-to-left shunt. DESIGN: A retrospective observational study. SETTING: One academic medical center from January 2017 to April 2020. PATIENTS: Patients older than 20 years who suffered from nontraumatic out-of-hospital cardiac arrest (OHCA) and underwent intra-arrest TEE. MEASUREMENT AND MAIN RESULTS: Patients who had microbubbles resulting from fluid injection in the right atrium, as indicated on TEE imaging, were included in the analysis. The presence of right-to-left shunt was defined as the appearance of microbubbles in the systemic circulation, including the left atrium, left ventricle, or aorta. A total of 97 patients were included in the final analysis. A right-to-left shunt was observed in 21 patients (21.6%), and no shunt was found in 76 patients (78.4%). The degree of the right-to-left shunt, determined by the number of microbubbles, was mild in 11 patients (52.4%), moderate in eight (38.0%), and severe in two (9.6%). Multivariate analysis showed that no factors were associated with the presence of right-to-left shunt during CPR. CONCLUSIONS: Right-to-left shunts can be appreciated during CPR in patients who experience OHCA. Further studies are needed to verify its clinical significance.

Trends in maintenance status and usability of public automated external defibrillators during a 5-year on-site inspection.

This study aimed to assess the trend of the maintenance status and usability of public automated external defibrillators (AEDs). Public AEDs installed in Seoul from 2013 to 2017 were included. An inspector checked the maintenance status and usability of the AEDs annually using a checklist. During the study period, 23,619 AEDs were inspected. Access to the AEDs was improved, including the absence of obstacles near the AEDs (from 90.2% in 2013 to 99.1% in 2017, p < 0.0001) and increased AED signs (from 34.3% in 2013 to 91.3% in 2017, p < 0.0001). The rate of AEDs in normal operation (from 94.0% in 2013 to 97.6% in 2017, p < 0.0001), good battery status (from 95.6% in 2013 to 96.8% in 2017, p = 0.0016), and electrode availability increased (from 97.1% in 2013 to 99.0% in 2017, p < 0.0001); the rate of electrode validity decreased (from 90.0% in 2013 to 87.2% in 2017, p < 0.0001). The overall rate of the non-ready-to-use AEDs and AEDs with less than 24-h usability accounted for 15.4% and 44.1% of the total number of AEDs, respectively. Although most AEDs had a relatively good maintenance status, a significant proportion of public AEDs were not available for 24-h use. Invalid electrodes and less than 24-h accessibility were the main reasons that limited the 24-h usability of public AEDs.

Healthy lifestyle factors, cardiovascular comorbidities, and the risk of sudden cardiac arrest: A case-control study in Korea.

AIMS: We investigated the impact of healthy lifestyle factors and cardiovascular comorbidities for sudden cardiac arrest. METHODS: A case-control study, including patients with sudden cardiac arrest aged 20-79 years and community-based 1:2 matched controls, was conducted from September 2017 to December 2020. All participants completed a structured questionnaire. Using multivariable logistic regression, we assessed cardiovascular comorbidities (diabetes, hypertension, dyslipidaemia, myocardial infarction, congestive heart failure, arrhythmia, and stroke) and healthy lifestyle factors (low red meat consumption, low fish consumption, high fruit consumption, high vegetable consumption, current non-smoking, regular exercise, and adequate sleep duration) as sudden cardiac arrest risk factors. RESULTS: Among 3027 eligible cases, informed consent was obtained from 949 (31.3%) cases. A total of 1731 controls were enrolled. Cardiovascular comorbidities, except dyslipidaemia, were associated with an increased risk of sudden cardiac arrest, whereas all healthy lifestyle factors were associated with a decreased risk. Relative to patients in the 0-2 healthy lifestyle factors group, the adjusted odds ratio (95% confidence interval) for sudden cardiac arrest was 0.25 (0.16-0.40) in patients with 3 healthy lifestyle factors, 0.08 (0.05-0.13) in patients with 4 healthy lifestyle factors, and 0.04 (0.03-0.06) in patients with over 5 healthy lifestyle factors. When the number of healthy lifestyle factors was analysed as a continuous variable, each additional factor was associated with a significant decrease in the likelihood of sudden cardiac arrest (adjusted odds ratio [95% confidence interval]: 0.41 [0.36-0.46]). CONCLUSION: The increased risk of sudden cardiac arrest by cardiovascular comorbidities could be significantly reduced with healthy lifestyle factors.

Dielectric Engineering to Suppress Cell-to-Cell Programming Voltage Interference in 3D NAND Flash Memory.

In contrast to conventional 2-dimensional (2D) NAND flash memory, in 3D NAND flash memory, cell-to-cell interference stemming from parasitic capacitance between the word-lines (WLs) is difficult to control because the number of WLs, achieved for better packing density, have been dramatically increased under limited height of NAND string. In this context, finding a novel approach based on dielectric engineering seems timely and applicable. This paper covers the voltage interference characteristics in 3D NAND with respect to dielectrics, then proposes an alternative cell structure to suppress such interference.

Comparison of Resuscitation Outcomes Between 2- or 3-Stacked Defibrillation Strategies With Minimally Interrupted Chest Compression and the Single Defibrillation Strategy: A Swine Cardiac Arrest Model.

Background There is controversy over whether the number and mode of electrical shock are optimal for successful defibrillation. Methods and Results Fifty-four pigs were randomly assigned to 3 groups. After inducing ventricular fibrillation and a 2-minute downtime, basic life support was initiated with a 30:2 compression/ventilation ratio for 8 minutes. Subsequently, 20 minutes of advanced life support, including asynchronous ventilation, every 10 chest compressions with 15 L/min of oxygen, was delivered. Animals of the single shock group received a single shock, animals of the 2-stacked shock group received 2 consecutive shocks, and animals of the 3-stacked shock group received 3 consecutive shocks. Animals with the return of spontaneous circulation underwent post-cardiac arrest care for 12 hours. The rates of successful defibrillation, return of spontaneous circulation, 24-hour survival, and 48-hour survival and neurological deficit score were compared between the groups. Hemodynamic parameters, arterial blood gas profiles, troponin I, and cardiac output were not different between the groups. There was a significant difference in chest compression fraction between the single and 3-stacked shock groups (P<0.001), although there was no difference between the single and 2-stacked shock groups (P=0.022) or the 2-stacked and 3-stacked shock groups (P=0.040). The rates of successful defibrillation, return of spontaneous circulation, 24-hour survival, and 48-hour survival were higher in the 2- and 3-stacked shock groups than in the single shock group (P=0.021, P=0.015, and P=0.021, respectively). Neurological deficit score at 48 hours was not different between the groups. Conclusions A stacked shock strategy was superior to a single shock strategy for successful defibrillation and better resuscitation outcomes in treating ventricular fibrillation.