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.

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.

A simple scoring rule to predict survival to discharge after out of hospital cardiac arrest at the time of ED arrival.

BACKGROUND: It is important to be able to predict the chance of survival to hospital discharge upon ED arrival in order to determine whether to continue or terminate resuscitation efforts after out of hospital cardiac arrest. This study was conducted to develop and validate a simple scoring rule that could predict survival to hospital discharge at the time of ED arrival. METHODS: This was a multicenter retrospective cohort study based on a nationwide registry (Korean Cardiac Arrest Research Consortium) of out of hospital cardiac arrest (OHCA). The study included adult OHCA patients older than 18 years old, who visited one of 33 tertiary hospitals in South Korea from September 1st, 2015 to June 30th, 2020. Among 12,321 screened, 5471 patients were deemed suitable for analysis after exclusion. Pre-hospital ROSC, pre-hospital witness, shockable rhythm, initial pH, and age were selected as the independent variables. The dependent variable was set to be the survival to hospital discharge. Multivariable logistic regression (LR) was performed, and the beta-coefficients were rounded to the nearest integer to formulate the scoring rule. Several machine learning algorithms including the random forest classifier (RF), support vector machine (SVM), and K-nearest neighbor classifier (K-NN) were also trained via 5-fold cross-validation over a pre-specified grid, and validated on the test data. The prediction performances and the calibration curves of each model were obtained. Pre-processing of the registry was done using R, model training & optimization using Python. RESULTS: A total of 5471 patients were included in the analysis. The AUROC of the scoring rule over the test data was 0.7620 (0.7311-0.7929). The AUROCs of the machine learning classifiers (LR, SVM, k-NN, RF) were 0.8126 (0.7748-0.8505), 0.7920 (0.7512-0.8329), 0.6783 (0.6236-0.7329), and 0.7879 (0.7465-0.8294), respectively. CONCLUSION: A simple scoring rule consisting of five, binary variables could aid in the prediction of the survival to hospital discharge at the time of ED arrival, showing comparable results to conventional machine learning classifiers.

Circulating Vitamin D Level and Risk of Sudden Cardiac Death and Cardiovascular Mortality: A Dose-Response Meta-Analysis of Prospective Studies.

BACKGROUND: We conducted a comprehensive meta-analysis of prospective cohort studies to analyze the effect of circulating vitamin D level on the risk of sudden cardiac death (SCD) and cardiovascular disease (CVD) mortality. METHODS: Prospective cohort studies evaluating the association between circulating vitamin D and risk of SCD and CVD mortality were systematically searched in the PubMed and Embase. Extracted data were analyzed using a random effects model and results were expressed in terms of hazard ratio (HR) and 95% confidence interval (CI). Restricted cubic spline analysis was used to estimate the dose-response relationships. RESULTS: Of the 1,321 records identified using the search strategy, a total of 19 cohort studies were included in the final meta-analysis. The pooled estimate of HR (95% CI) for low vs. high circulating vitamin D level was 1.75 (1.49-2.06) with I² value of 30.4%. In subgroup analysis, strong effects of circulating vitamin D were observed in healthy general population (pooled HR, 1.84; 95% CI, 1.43-2.38) and the clinical endpoint of SCD (pooled HRs, 2.68; 95% CI, 1.48-4.83). The dose-response analysis at the reference level of < 50 nmol/L showed a significant negative association between circulating vitamin D and risk of SCD and CVD mortality. CONCLUSION: Our meta-analysis of prospective cohort studies showed that lower circulating vitamin D level significantly increased the risk of SCD and CVD mortality.

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.

Cystatin C and mortality risk in the general population: systematic review and dose response meta-analysis.

INTRODUCTION: Cystatin C has been identified as an independent predictor of all-cause and cardiovascular mortality in the general population. This meta-analysis to evaluate the association between serum cystatin C level and all-cause and cardiovascular mortality. We additionally conducted a dose-response analysis to examine a linear association between cystatin C and cardiovascular mortality. METHODS: PudMed and Embase databases were searched until January, 2021. All prospective cohort studies that reported a multivariate-adjusted risk estimated of all-cause and cardiovascular mortality for the highest compared with lowest cystatin C level were included. RESULTS: 13 prospective cohort studies, a total of 57,214 participants were included in this analysis. Meta-analysis indicated that the highest compared with lowest cystatin C level was associated with an increase of all-cause mortality (hazard ratio [HR]: 2.01; 95% confidence intervals [CI]: 1.60-2.53; I2=89%) and cardiovascular mortality (2.62 [1.96-3.51]; I2=52%). We found a significant log-linear dose-response association between cystatin C and cardiovascular mortality (p < 0.01). Every 0.1 mg/L increase in cystatin C level was associated with a 7.3% increased cardiovascular mortality. CONCLUSIONS: Elevated serum cystatin C is associated with an increased risk of all-cause and cardiovascular mortality in the general populations. Particularly, cystatin C level and cardiovascular mortality showed linear correlation.

Diagnosis of aortic dissection by transesophageal echocardiography during cardiopulmonary resuscitation.

OBJECTIVES: Early identification of the causes of cardiac arrest is helpful in determining the resuscitation measures during cardiopulmonary resuscitation (CPR). We aimed to evaluate the feasibility of transesophageal echocardiography (TEE) during CPR in diagnosing aortic dissection and the influence of aortic dissection on resuscitation outcome in adult patients with prolonged non-traumatic cardiac arrest. METHODS: Adult patients aged >20 years with non-traumatic cardiac arrest who underwent prolonged CPR (>10 min) and TEE examination during CPR were enrolled. The enrolled patients were grouped according to the presence of aortic dissection on TEE: the aortic dissection (AD) group and the non-AD group. Variables related to cardiac arrest event, CPR, and resuscitation outcome were compared between the two groups. RESULTS: Forty-five patients (median age, 71 years; 26 men) were enrolled. Ten (22.2%) and 35 (77.8%) patients were included in the AD and non-AD groups, respectively. No patients in the AD group survived. Aortic dissection on TEE was inversely related to the rate of return of spontaneous circulation on multivariate analysis (odds ratio, 0.019; 95% confidence interval, 0.001-0.750; p = .035). CONCLUSION: TEE is a useful tool for diagnosing aortic dissection as a cause of cardiac arrest during CPR. Aortic dissection is associated with poor resuscitation outcomes.

Delayed Splenic Rupture: A Rare Complication of Snakebites.

Bites by venomous snakes can cause fatal systemic and coagulation disorders. Rare complications, such as compartment syndrome and hemoperitoneum, may also require surgical intervention. Here, we describe our experience with an unusual case of snakebite-induced delayed splenic rupture. A 54-y-old male with no specific medical history visited a local hospital for a bite by an unidentified snake. He had been bitten on the left thumb and was administered antivenom. He was discharged from the local hospital after 3 d when his symptoms had improved. However, he revisited our emergency medical center 2 d later, reporting dizziness with diaphoresis. Focused abdominal ultrasonography and computed tomography revealed large amounts of intraperitoneal fluid collection and hemoperitoneum with splenic rupture, respectively. The patient underwent immediate blood transfusion and received antivenom treatment in our emergency department and, subsequently, emergency splenectomy. Histopathologic findings at the time of surgery revealed multifocal lacerations on the external surface of the spleen, with fresh hemorrhage. He recovered 7 d after surgery without any complication.

Effects of Adjunctive Therapeutic Hypothermia Combined With Hyperbaric Oxygen Therapy in Acute Severe Carbon Monoxide Poisoning.

OBJECTIVE: To determine the effects of adjunctive therapeutic hypothermia, by comparing hyperbaric oxygen therapy versus hyperbaric oxygen therapy combined with therapeutic hypothermia in acute severe carbon monoxide poisoning. DESIGN: Retrospective analysis of data from our prospectively collected carbon monoxide poisoning registry. SETTING: A single academic medical center in Wonju, Republic of Korea. PATIENTS: Patients with acute severe carbon monoxide poisoning older than 18 years. Acute severe carbon monoxide poisoning was defined as mental status showing response to painful stimulus or unresponsive at the emergency department, and a continuation of this depressed mental status even after the first hyperbaric oxygen therapy. Patients were classified into the no-therapeutic hypothermia and therapeutic hypothermia groups. Hyperbaric oxygen therapy was performed up to twice within 24 hours after emergency department arrival, whereas therapeutic hypothermia was performed at a body temperature goal of 33°C for 24 hours using an endovascular cooling device after the first hyperbaric oxygen therapy. INTERVENTIONS: Hyperbaric oxygen therapy versus hyperbaric oxygen therapy combined with therapeutic hypothermia. MEASUREMENTS AND MAIN RESULTS: We investigated the difference in the Global Deterioration Scale score at 1 and 6 months after carbon monoxide exposure, between the no-therapeutic hypothermia and therapeutic hypothermia groups. Global Deterioration Scale scores were classified as follows: 1-3 points (favorable neurocognitive outcome) and 4-7 points (poor neurocognitive outcome). During the study period, 37 patients were treated for acute severe carbon monoxide poisoning, with 16 and 21 patients in the no-therapeutic hypothermia and therapeutic hypothermia groups, respectively. The therapeutic hypothermia group demonstrated significantly higher number of patients with favorable outcomes (p = 0.008) at 6 months after carbon monoxide exposure and better improvement of the 6-month Global Deterioration Scale score than the 1-month score (p = 0.006). CONCLUSIONS: Our data suggest that in acute severe carbon monoxide poisoning, patients who were treated using therapeutic hypothermia combined with hyperbaric oxygen therapy had significantly more favorable neurocognitive outcomes at 6 months after carbon monoxide exposure than those treated with hyperbaric oxygen therapy alone.

Cardiopulmonary resuscitation may cause paradoxical embolism.

This paper reports a case of paradoxical embolism of right heart thrombi visualized on transesophageal echocardiography during cardiopulmonary resuscitation (CPR). CPR may cause a right-to-left shunt by producing a sudden increase in right atrial pressure during the compression phase. In cardiac arrest patients with right heart thrombi who have received CPR, systemic embolization can occur owing to paradoxical embolism.

Predictive Value of the Neutrophil-to-Lymphocyte Ratio for the Diagnosis of Pneumonia in Normothermic Dyspneic Patients with Chronic Heart Failure in the Emergency Department.

BACKGROUND: Differentiating pneumonia from chronic heart failure (HF) in normothermic subjects in the emergency department (ED) is significantly difficult. OBJECTIVE: This study aimed to evaluate the predictive value of the neutrophil-to-lymphocyte ratio (NLR) in establishing the diagnosis of pneumonia in normothermic subjects with chronic HF in the ED. METHODS: This study included 523 adult dyspneic patients with chronic HF presenting in the ED. We categorized the selected patients into the nonpneumonia group (NPG) and the pneumonia group (PG), and the patients' serum white blood cell (WBC), neutrophil, and lymphocyte counts, NLR, and C-reactive protein (CRP) levels were measured upon arrival in the ED. Subsequently, we compared their predictive powers after performing a propensity score-matching (PSM) analysis. RESULTS: The PG included 120 (22.9%) patients. After performing PSM, the mean NLR was significantly higher in the PG than in the NPG group (p < 0.001). According to the receiver operating characteristic area under the curve (AUC) analysis of inflammatory markers, the AUC of the NLR was significantly higher than that of WBCs, neutrophils, lymphocytes, and CRP. CONCLUSION: The predictive value of the NLR was significantly higher than that of WBCs, neutrophils, lymphocytes, and CRP. Therefore, NLR may be a useful adjunctive marker to establish the early diagnosis of pneumonia in normothermic patients with chronic HF in the ED.

Factors for modifying the termination of resuscitation rule in out-of-hospital cardiac arrest.

BACKGROUND: False positive rate (FPR) of the current basic life support (BLS) termination of resuscitation (TOR) rule in out-of-hospital cardiac arrest (OHCA) patients (not witnessed; no return of spontaneous circulation prior to transport; and no shocks were delivered) has been ethically challenging. We validated the current BLS TOR rule with using nationwide Korean Cardiac Arrest Research Consortium (KoCARC) registry and identified the factors for modifying the rules. METHODS: This prospective, multicenter, registry-based study was performed using the nontraumatic OHCA registry data between October 2015 and June 2017. Independent factors associated with poor neurologic outcome were identified to propose new KoCARC TOR rules by using multivariable analysis. The diagnostic performances of the TOR rules were calculated respectively. RESULTS: Among 4,360 OHCA patients, 2,801 (64.2%) satisfied all 3 criteria of the BLS TOR rule. The FPR and positive predictive value of the BLS TOR rule were 5.9% and 99.3%. Asystole as initial rhythm and age > 60 years were found as new factors for modifying the TOR rule. New KoCARC TOR rules, combination of asystole and age > 60 years with current TOR rule, showed lower FPR (0.3%-2.1%) and higher positive predictive value (99.7%-99.9%) for predicting poor neurologic outcome at discharge. CONCLUSIONS: In this recent nationwide cohort, the current BLS TOR rule showed high FPR (5.9%) for predicting poor neurologic outcome. We anticipate that our new KoCARC TOR rules, application of 2 new factors (asystole as initial rhythm and age > 60 years) with BLS TOR rule, could reduce unwarranted death.

The gradient between arterial and end-tidal carbon dioxide predicts in-hospital mortality in post-cardiac arrest patient.

PURPOSE: We investigated the predictive value of the gradient between arterial carbon dioxide (PaCO2) and end-tidal carbon dioxide (ETCO2) (Pa-ETCO2) in post-cardiac arrest patients for in-hospital mortality. METHODS: This retrospective observational study evaluated cardiac arrest patients admitted to the emergency department of a tertiary university hospital. The PaCO2 and ETCO2 values at 6, 12, and 24 h after return of spontaneous circulation (ROSC) were obtained from medical records and Pa-ETCO2 gap was calculated as the difference between PaCO2 and ETCO2 at each time point. Multivariate logistic regression analysis was performed to verify the relationship between Pa-ETCO2 gap and clinical variables. Receiver operating characteristic (ROC) curve analysis was performed to determine the cutoff value of Pa-ETCO2 for predicting in-hospital mortality. RESULTS: The final analysis included 58 patients. In univariate analysis, Pa-ETCO2 gaps were significantly lower in survivors than in non-survivors at 12 h [12.2 (6.5-14.8) vs. 13.9 (12.1-19.6) mmHg, p = 0.040] and 24 h [9.1 (6.3-10.5) vs. 17.1 (13.1-23.2) mmHg, p < 0.001)] after ROSC. In multivariate analysis, Pa-ETCO2 gap at 24 h after ROSC was related to in-hospital mortality [odds ratio (95% confidence interval): 1.30 (1.07-1.59), p = 0.0101]. In ROC curve analysis, the optimal cut-off value of Pa-ETCO2 gap at 24 h after ROSC was 10.6 mmHg (area under the curve, 0.843), with 77.8% sensitivity and 85.7% specificity. CONCLUSION: The Pa-ETCO2 gap at 24 h after ROSC was associated with in-hospital mortality in post-cardiac arrest patients.

New Termination-of-Resuscitation Models and Prognostication in Out-of-Hospital Cardiac Arrest Using Electrocardiogram Rhythms Documented in the Field and the Emergency Department.

BACKGROUND: Electrocardiogram (ECG) rhythms, particularly shockable rhythms, are crucial for planning cardiac arrest treatment. There are varying opinions regarding treatment guidelines depending on ECG rhythm types and documentation times within pre-hospital settings or after hospital arrivals. We aimed to determine survival and neurologic outcomes based on ECG rhythm types and documentation times. METHODS: This prospective observational study of 64 emergency medical centers was performed using non-traumatic out-of-hospital cardiac arrest registry data between October 2015 and June 2017. From among 4,608 adult participants, 4,219 patients with pre-hospital and hospital ECG rhythm data were enrolled. Patients were divided into 3 groups: those with initial-shockable, converted-shockable, and never-shockable rhythms. Patient characteristics and survival outcomes were compared between groups. Further, termination of resuscitation (TOR) validation was performed for 6 combinations of TOR criteria confirmed in previous studies, including 2 rules developed in the present study. RESULTS: Total survival to discharge after cardiac arrest was 11.7%, and discharge with good neurologic outcomes was 7.9%. Survival to discharge rates and favorable neurologic outcome rates for the initial-shockable group were the highest at 35.3% and 30.2%, respectively. There were no differences in survival to discharge rates and favorable neurologic outcome rates between the converted-shockable (4.2% and 2.0%, respectively) and never-shockable groups (5.7% and 1.9%, respectively). Irrespective of rhythm changes before and after hospital arrival, TOR criteria inclusive of unwitnessed events, no pre-hospital return of spontaneous circulation, and asystole in the emergency department best predicted poor neurologic outcomes (area under the receiver operating characteristic curve of 0.911) with no patients classified as Cerebral Performance Category 1 or 2 (specificity = 1.000). CONCLUSION: Survival outcomes and TOR predictions varied depending on ECG rhythm types and documentation times within pre-hospital filed or emergency department and should, in the future, be considered in treatment algorithms and prognostications of patients with out-of-hospital cardiac arrest. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03222999.

Operation of a hyperbaric oxygen therapy center in Korea: Report of our experience from a setting in its nascent stages.

Purpose: Hyperbaric medicine is nascent in Korea when compared to other developed countries, such as the United States and Japan. Our facility has been managed by physicians with certifications from the Undersea and Hyperbaric Medical Society (UHMS) and National Oceanic and Atmospheric Administration in diving and clinical diseases since October 2016. This study was conducted to share similar issues that are encountered during the establishment of a program in a new area through our experiences in the operation of a hyperbaric oxygen (HBO2) therapy center. Methods: In this retrospective observational study we collected data on HBO2 patients treated at our center between October 2016 and June 2018 after HBO2 was conducted by HBO2-certified physicians. We then compared demographic data of patients with data from January 2011 to September 2015 - before HBO2 operations were conducted by HBO2-certified physicians. Result: A total of 692 patients received 5,130 treatments. Twelve indicated diseases were treated using HBO2 therapy. Fifty-six critically ill patients with intubation received HBO2. Although two patients experienced seizure due to oxygen toxicity during the study period, certified physicians and inside attendant took immediate corrective action. Conclusion: After the establishment of the HBO2 center operated by physicians with certification, more patients, including critically ill patients, received HBO2 safely for various diseases. In order to improve the practice of hyperbaric medicine in Korea, the Korean Academy of Undersea and Hyperbaric Medicine (KAUHM), an advanced and well-organized academic society, should communicate often with HBO2 centers, with the aim to set Korean education programs at UHMS course levels and increase reimbursement for HBO2 therapy.

Effect of Automated Simultaneous Sternothoracic Cardiopulmonary Resuscitation Device on Hemodynamics in Out-of-Hospital Cardiac Arrest Patients.

BACKGROUND: An automatic simultaneous sternothoracic cardiopulmonary resuscitation (SST-CPR) device is an apparatus that performs CPR by providing simultaneous cyclic compressions of the thorax with a thoracic strap and compression of the sternum with a piston. OBJECTIVE: This study was conducted to compare the hemodynamic effects of CPR with an automatic SST-CPR device to those with standard CPR (STD-CPR) in cardiac arrest patients. METHODS: A randomized trial was performed on victims of out-of-hospital cardiac arrest resistant to initial 20 min of CPR after emergency department (ED) arrival. Patients were instrumented with femoral arterial and internal jugular venous lines before enrollment. Informed consent was waived per protocol. Patients were randomized to SST-CPR or STD-CPR based on the day of the month. The primary outcome was a comparison of the mean estimated coronary perfusion pressure (CPP) between SST-CPR and STD-CPR. The secondary outcome was a comparison of compression arterial systolic pressure, compression arterial diastolic pressure, right atrial systolic pressure, right atrial diastolic pressure, return of spontaneous circulation rate, survival to hospital admission, survival at 30 days, favorable neurologic outcomes at 30 days, and adverse events between two groups. RESULTS: Of 62 patients with non-traumatic, adult, out-of-hospital cardiac arrest who presented to the ED, 24 received CPR with an automatic SST-CPR device (SST-CPR group), and 38 received standard CPR (STD-CPR group). Acquisition and analysis of hemodynamic data were completed in 11 (46%) patients in the SST-CPR group and 14 (37%) patients in the STD-CPR group. Compression arterial systolic pressure, right atrial systolic/diastolic pressures, and end-tidal carbon dioxide tension were not different between the two groups. Median compression arterial diastolic pressure (femoral arterial pressure during relaxation) was 20 mm Hg (mean 22 mm Hg; 95% confidence interval [CI] 5 to 38 mm Hg) and 0 mm Hg (mean -2 mm Hg; 95% CI -21 to 18 mm Hg) in the SST-CPR group and the STD-CPR group (p = 0.002), respectively. Median estimated CPP was 10 mm Hg (mean 16 mmHg; 95% CI 1 to 31 mm Hg) and 2 mm Hg (mean 4 mm Hg; 95% CI -4 to 12 mm Hg) in the SST-CPR group and the STD-CPR group (p = 0.017), respectively. CONCLUSIONS: CPR with an automatic SST-CPR device results in higher estimated CPP compared to standard CPR in patients with non-traumatic, out-of-hospital cardiac arrest.

Parenchymal lung injuries related to standard cardiopulmonary resuscitation.

OBJECTIVES: We analyzed chest computed tomographic scan to evaluate parenchymal lung injury and its clinical significance in patients who received standard cardiopulmonary resuscitation and were resuscitated from cardiac arrest. METHODS: We enrolled nontraumatic out-of-hospital cardiac arrest patients older than 19 years who had been admitted to the emergency department in cardiac arrest and successfully resuscitated after cardiopulmonary resuscitation. Chest computed tomography was obtained immediately after return of spontaneous circulation (ROSC). To allocate the area of lung contusion, we divided both hemithoraces into 3 regions longitudinally, and each part was subdivided into 4 segments except the lower part of the left lung. To stratify the severity of lung contusion, each segment was scored depending on the area of lung contusion. Oxygen index (OI) was measured at the time of ROSC, 24, 48, and 72 hours and 1 week after cardiac arrest. RESULTS: Lung contusion was developed in 37 (41%) patients and median lung contusion score (LCS) was 17 (12-26). Lung contusion was not associated with hospital mortality (P = .924) or length of intensive care unit stay (P = .446). The OI at the time of ROSC was lower in patients with LCS greater than 23 than that in patients with LCS less than or equal to 23 (126 [93-224] vs 278 [202-367]; P = .008); however, the OI at the other timelines was not different between patients with LCS greater than 23 and patients with LCS less than or equal to 23. CONCLUSION: Extensive lung contusion is associated with a lower oxygenation index at the time of ROSC, but did not affect the resuscitation outcome.

Reduced Mortality in Severely Injured Patients Using Hospital-based Helicopter Emergency Medical Services in Interhospital Transport.

Recent evidence has demonstrated the survival benefits of helicopter transport for trauma patients. The purpose of this study was to evaluate the effectiveness of hospital-based helicopter emergency medical services (H-HEMS) in comparison with ground ambulance transport in improving mortality outcomes in patients with major trauma. Study participants were divided into 2 groups according to type of transport to the trauma center; that is, either via ground emergency medical services (GEMS) or via H-HEMS. The study was conducted from October 2013 to July 2015. Mortality outcomes in the H-HEMS group were compared with those in the GEMS group by using the Trauma and Injury Severity Score (TRISS) analysis. The number of participants finally included in the study was 312. Among these patients, 63 were adult major trauma patients transported via H-HEMS, and 47.6% were involved in traffic accidents. For interhospital transport, the Z and W statistics revealed significantly higher scores in the H-HEMS group than in the GEMS group (Z statistic, 2.02 vs. 1.16; P = 0.043 vs. 0.246; W statistic, 8.87 vs. 2.85), and 6.02 more patients could be saved per 100 patients when H-HEMS was used for transportation. TRISS analysis revealed that the use of H-HEMS for transporting adult major trauma patients was associated with significantly improved survival compared to the use of GEMS.

Evaluation of myocardial injury through serum troponin I and echocardiography in anaphylaxis.

BACKGROUND: Anaphylaxis is an acute, lethal, multisystem syndrome that results from the sudden release of mast cell- and basophil-derived mediators. Although anaphylaxis can cause cardiac complications, the incidence of myocardial injury using troponin I (TnI) has not been characterized. In addition, patterns of cardiomyopathy have not been evaluated in patients with elevated TnI. Therefore, we studied the occurrence and patterns of myocardial injury with TnI and echocardiography in anaphylaxis. METHODS: We conducted a retrospective review of 300 consecutive anaphylaxis cases that were diagnosed in the emergency department (ED) over 53 months (2011-2015). Myocardial injury was defined as elevation of TnI within 24hrs after arrival at the ED. We investigated systolic function and regional wall motion abnormality (RWMA) through echocardiography within 5 hours after arrival at the ED in patients with myocardial injury. RESULTS: Among 300 patients (median age, 55 years), 22 patients demonstrated myocardial injury (7.3%). The median TnI was 0.222 ng/mL with a range from 0.057 ng/mL to 19.4 ng/mL. Three patients presented reduced systolic function and 4 patients showed RWMA. One patient showed reverse Takotsubo cardiomyopathy and other 2 patients had RWMA discordant to the distribution of coronary arteries. Another patient showed RWMA (inferior wall) with ST elevation of II, III, and aVF. All 4 patients were discharge after recovery of cardiomyopathy without any specific intervention for cardiomyopathy. CONCLUSIONS: Myocardial injury developed in 7.3% of patients with anaphylaxis. Various cardiomyopathy, including Kounis syndrome and Takotsubo cardiomyopathy, has been observed in patients with myocardial injury.

The utility of noninvasive nasal positive pressure ventilators for optimizing oxygenation during rapid sequence intubation.

OBJECTIVES: The objective of the study is to investigate the feasibility of noninvasive nasal positive pressure ventilation (NINPPV) for optimizing oxygenation during the rapid sequence intubation in critically ill patients. METHODS: A prospective, observational study was performed in an emergency department. Noninvasive nasal positive pressure ventilation was applied in the preoxygenation step and maintained until successful intubation. A pulse oximetry (Spo2) was continuously monitored throughout the procedure and recorded 5 times. The degree of interfering was surveyed with 10-point Likert scale. RESULTS: Thirty patients were enrolled. The most of enrolled patients were diagnosed as pneumonia, acute heart failure, and traumatic brain injury. The Spo2 was increased to 100% (98%-100%) at the time of starting endotracheal intubation with NINPPV and maintained as 97% (95%-100%) until successful intubation (P< .001). Total apnea duration was 195 seconds (190-196). The degree of interfering intubation was 1 (0-1). CONCLUSIONS: Noninvasive nasal positive pressure ventilation would be useful for optimizing oxygenation during rapid sequence intubation.