Improving oxygenation in a patient with respiratory failure due to morbid obesity by applying airway pressure release ventilation: a case report.

INTRODUCTION: Morbidly obese patients occasionally have respiratory problems owing to hypoventilation. Airway pressure release ventilation is one of the ventilation settings often used for respiratory management of acute respiratory distress syndrome. However, previous reports indicating that airway pressure release ventilation may become a therapeutic measure as ventilator management in morbid obesity with respiratory failure is limited. We report a case of markedly improved oxygenation in a morbidly obese patient after airway pressure release ventilation application. CASE REPORT: A 50s-year-old Asian man (body mass index 41 kg/m2) presented with breathing difficulties. The patient had respiratory failure with a PaO2/FIO2 ratio of approximately 100 and severe atelectasis in the left lung, and ventilator management was initiated. Although the patient was managed on a conventional ventilate mode, oxygenation did not improve. On day 11, we changed the ventilation setting to airway pressure release ventilation, which showed marked improvement in oxygenation with a PaO2/FIO2 ratio of approximately 300. We could reduce sedative medication and apply respiratory rehabilitation. The patient was weaned from the ventilator on day 29 and transferred to another hospital for further rehabilitation on day 31. CONCLUSION: Airway pressure release ventilation ventilator management in morbidly obese patients may contribute to improving oxygenation and become one of the direct therapeutic measures in the early stage of critical care.

Impact of pre-existing medical conditions on mortality in geriatric trauma: a nationwide study in Japan.

PURPOSE: To investigate the relationship between pre-existing medical conditions and outcomes in elderly trauma patients in Japan. METHODS: This multicenter observational study utilized data from the Japan Trauma Data Bank (JTDB) from 2019 to 2020. The primary outcome was in-hospital mortality. Factors associated with in-hospital mortality were identified using multivariate logistic regression analysis, from which adjusted odds ratios (AOR) and 95% confidence intervals (CI) were determined. RESULTS: Of the participants during the study period, 19,598 patients were included in the analysis. Among the pre-existing medical conditions, moderate or severe liver disease showed the strongest positive association with in-hospital mortality (AOR: 7.087, 95% CI: 3.194-15.722), followed by multiple malignancies (AOR: 3.490, 95% CI: 1.046-11.641), congestive heart failure (AOR: 2.572, 95% CI: 1.920-3.445), and moderate or severe renal disease (AOR: 2.256, 95% CI: 1.584-3.215). CONCLUSION: Data from JTDB suggests that pre-existing conditions like moderate or severe liver disease, congestive heart failure, and moderate or severe renal disease in elderly trauma patients are positively correlated with in-hospital mortality.

Uterine rupture successfully treated with a damage-control strategy of hysterectomy and resuscitative endovascular balloon occlusion of the aorta-assisted cardiopulmonary resuscitation.

Background: Uterine rupture is a major cause of postpartum hemorrhage (PPH) that requires surgery. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is also helpful for PPH. However, the effectiveness of REBOA in PPH with cardiac arrest is unknown. Case Presentation: A 40-year-old woman developed hemorrhagic shock due to uterine rupture after an induced delivery. She developed cardiac arrest, but was rescued by cardiopulmonary resuscitation (CPR), REBOA, a hysterectomy, and pelvic gauze packing. The hemodynamics were too unstable to move to the operating room. Then we initiated the CPR assisted with REBOA and decided to activate massive transfusion and perform laparotomy in the emergency room. She was finally discharged home without neurological sequelae. Conclusion: Our damage control strategy, including REBOA-assisted CPR, contributed to saving the life of a patient with a life-threatening PPH.

Association between time-dependent changes in cerebrovascular autoregulation after cardiac arrest and outcomes: A prospective cohort study.

This prospective observational single-center cohort study aimed to determine an association between cerebrovascular autoregulation (CVAR) and outcomes in hypoxic-ischemic brain injury post-cardiac arrest (CA), and assessed 100 consecutive post-CA patients in Japan between June 2017 and May 2020 who experienced a return of spontaneous circulation. Continuous monitoring was performed for 96 h to determine CVAR presence. A moving Pearson correlation coefficient was calculated from the mean arterial pressure and cerebral regional oxygen saturation. The association between CVAR and outcomes was evaluated using the Cox proportional hazard model; non-CVAR time percent was the time-dependent, age-adjusted covariate. The non-linear effect of target temperature management (TTM) was assessed using a restricted cubic spline. Of the 100 participants, CVAR was detected using the cerebral performance category (CPC) in all patients with a good neurological outcome (CPC 1-2) and in 65 patients (88%) with a poor outcome (CPC 3-5). Survival probability decreased significantly with increasing non-CVAR time percent. The TTM versus the non-TTM group had a significantly lower probability of a poor neurological outcome at 6 months with a non-CVAR time of 18%-37% (p < 0.05). Longer non-CVAR time may be associated with significantly increased mortality in hypoxic-ischemic brain injury post-CA.

Impact of the COVID-19 pandemic on epidemiology, treatment, and outcome of major trauma in Japan in 2020: a retrospective observational nationwide registry-based study.

Aim: The nationwide impact of the coronavirus disease (COVID-19) pandemic on major trauma in Japan is unknown. The nationwide registry-based data of the Japanese Trauma Data Bank were analyzed to elucidate the impact of COVID-19 on the epidemiology, treatment, and outcomes of major trauma patients. Methods: Among patients transported directly from the injury site by ambulance with an Injury Severity Score of ≥16, we compared patients managed from April to December in 2019 to those managed from April to December in 2020. Results: In total, 9792 patients were included in this study (2019, n = 5194; 2020, n = 4598). There were no significant differences in age or sex, but there were significant differences between 2019 and 2020 in the rates of "self-injury (suicide)", "motor vehicle accident", "fall from height", "fall down", and "fall to the ground", which are factors associated with patient age. Injury severity in 2019 and 2020 did not differ to a statistically significant extent, but the rate of major spinal injury increased. The time of prehospital care significantly increased in 2020 compared to 2019. There was no noticeable change in hospital treatment or in-hospital mortality between 2019 and 2020. Conclusion: This study suggests that the COVID-19 pandemic might have altered the injuries of major trauma; however, medical services for major trauma were well supplied in Japan in 2020.

Semi-quantitative evaluation of chest computed tomography for coronavirus disease 2019 in a critical care unit: A case-control study.

The spread of abnormal opacity on chest computed tomography (CT) has been reported as a predictor of coronavirus disease 2019 (COVID-19) severity; however, the relationship between CT findings and prognosis in patients with severe COVID-19 remains unclear. The objective of this study was to evaluate the extent of abnormal opacity on chest CT and its association with prognosis in patients with COVID-19 in a critical care medical center, using a simple semi-quantitative method. This single-center case-control study included patients diagnosed with severe COVID-19 pneumonia who were admitted to a critical care center. The diagnosis of COVID-19 was based on positive results of a reverse transcription polymerase chain reaction test. All patients underwent non-contrast whole-body CT upon admission. Six representative axial chest CT images were selected for each patient to evaluate the extent of lung lesions. The percentage of the area involved in the representative CT images was visually assessed by 2 radiologists and scored on 4-point scale to obtain the bedside CT score, which was compared between patients who survived and those who died using the Mann-Whitney U test. A total of 63 patients were included in this study: 51 survived and 12 died after intensive treatment. The inter-rater reliability of bedside scores between the 2 radiologists was acceptable. The median bedside CT score of the survival group was 12.5 and that of the mortality group was 16.5; the difference between the 2 groups was statistically significant. The degree of opacity can be easily scored using representative CT images in patients with severe COVID-19 pneumonia, without sophisticated software. A greater extent of abnormal opacity is associated with poorer prognosis. Predicting the prognosis of patients with severe COVID-19 could facilitate prompt and appropriate treatment.

Successful bronchial artery embolization using hydrogel coils for hemoptysis during extracorporeal membrane oxygenation.

A 58-year-old woman with bronchiectasis presented with massive hemoptysis and severe respiratory failure, which required long-term extracorporeal membrane oxygenation with continuous heparin infusion. Bronchial artery embolization using hydrogel coils, which provide a greater volume occlusion than bare platinum coils, was performed; hemoptysis stopped and she fully recovered. No recanalization was observed on follow-up computed tomography angiography 2 months postbronchial artery embolization, and there had been no recurrence of bleeding at the time of this report (at least 6 months). Although continuous anticoagulation during extracorporeal membrane oxygenation might hinder complete vessel occlusion by metallic coils or induce early recanalization (because the homeostatic mechanism of coils depends on the patient's coagulability), our experience showed that bronchial artery embolization using hydrogel coils was effective and safe. Additionally, this case presents a successful example of anticoagulation management for patients with hemoptysis on extracorporeal membrane oxygenation who undergo bronchial artery embolization using coils.

Factors Associated with Cardiac/Pericardial Injury among Blunt Injury Patients: A Nationwide Study in Japan.

The lack of established diagnostic criteria makes diagnosing blunt cardiac injury difficult. We investigated the factors associated with blunt cardiac injury using the Japan Trauma Data Bank (JTDB) in a multicenter observational study of blunt trauma patients conducted between 2004 and 2018. The primary outcome was the incidence of blunt cardiac/pericardial injury. Multivariable logistic regression analysis was used to identify factors independently associated with blunt cardiac injuries. Of the 228,513 patients, 1002 (0.4%) had blunt cardiac injury. Hypotension on hospital arrival (adjusted odds ratio (AOR) 4.536, 95% confidence interval (CI) 3.802-5.412), thoracic aortic injury (AOR 2.722, 95% CI 1.947-3.806), pulmonary contusion (AOR 2.532, 95% CI 2.204-2.909), rib fracture (AOR 1.362, 95% CI 1.147-1.618), sternal fracture (AOR 3.319, 95% CI 2.696-4.085). and hemothorax/pneumothorax (AOR 1.689, 95% CI 1.423-2.006)) was positively associated with blunt cardiac injury. Regarding the types of patients, car drivers had a higher rate of blunt cardiac injury compared to other types of patients. Driving a car, hypotension on hospital arrival, thoracic aortic injury, pulmonary contusion, rib fracture, sternal fracture, and hemothorax/pneumothorax were positively associated with blunt cardiac injury.

Relationship between in-hospital mortality and abdominal angiography among patients with blunt liver injuries: a propensity score-matching from a nationwide trauma registry of Japan.

AIM: To assess relationships between abdominal angiography and outcomes in adults with blunt liver injuries. METHODS: A retrospective observational study carried out from January 2004 to December 2018. Adult blunt-trauma patients with AAST grade Ⅲ-Ⅴ were analyzed with in-hospital mortality as the primary outcome using propensity-score-(PS) matching to seek associations with abdominal angiography findings. RESULTS: A total of 1,821 patients were included, of which 854 had available abdominal angiography data (AA+) and 967 did not (AA-). From these, 562 patients were selected from each group by propensity score matching. In-hospital mortality was found to be lower in the AA+ than in the AA- group (15.1% [87/562] versus 25.4% [143/562]; odds ratio 0.544, 95% confidence interval 0.398-0.739). CONCLUSION: Abdominal angiography is shown to be of benefit for adult patients with blunt liver injury in terms of their lower in-hospital mortality.

Energy expenditure and oxygen uptake kinetics in critically ill elderly patients.

BACKGROUND: Resting energy expenditure (REE) measurement of critically ill patients is essential for better nutrition management. Younger people increase their oxygen delivery ( ḊO2${\dot{{\rm{D}}}}{{\rm{O}}_2}$ ) to meet energy demands, but few reports have investigated oxygen uptake kinetics in elderly patients, which are the main target population in today's intensive care units (ICUs). In this study, we evaluated REE, ḊO2${\dot{{\rm{D}}}}{{\rm{O}}_2}$ , and oxygen extraction ratio (O2 Ext: oxygen consumption [ V̇O2${\dot{{\rm{V}}}}{{\rm{O}}_2}$ ]/ ḊO2${\dot{{\rm{D}}}}{{\rm{O}}_2}$ ) to clarify appropriate energy needs and consumption in elderly ICU patients. METHODS: This retrospective observational study included ventilated ICU patients who were divided into elderly participants (age ≥ 65 years) and nonelderly participants (age ≤64 years). V̇O2${\dot{{\rm{V}}}}{{\rm{O}}_2}$ , CO2 production, and cardiac output were measured by indirect calorimetry and noninvasive hemodynamic monitoring for up to 5 days. The initial values of REE, ḊO2${\dot{{\rm{D}}}}{{\rm{O}}_2}$ , and O2 Ext were compared between elderly and nonelderly patients. RESULTS: This study included 102 patients, of whom 52% (n = 53) were elderly. The absolute deviation of measured REE per ideal body weight (IBW) was significantly higher in elderly than in nonelderly patients (9.3 ± 6.9 vs 6.3 ± 6.6 kcal/kg; P < .01). ḊO2${\dot{{\rm{D}}}}{{\rm{O}}_2}$ had a strong negative correlation with age (P < .01). The O2 Ext value was significantly higher in elderly than in nonelderly patients (37 ± 19% vs 29 ± 13%; P = .03). CONCLUSIONS: Elderly critically ill patients were characterized by higher deviations in REE, lower ḊO2${\dot{{\rm{D}}}}{{\rm{O}}_2}$ , and higher O2 Ext. In elderly patients, O2 Ext rather than ḊO2${\dot{{\rm{D}}}}{{\rm{O}}_2}$ could be increased to meet energy consumption demands.

Dynamic changes of the hemoglobin index during resuscitation in patients with out-of-hospital cardiopulmonary arrest due to freshwater drowning: A retrospective observational study.

BACKGROUND: The hemoglobin index (HbI) represents the amount of hemoglobin, which reflects the regional tissue blood volume. The HbI is calculated by a regional oxygen saturation monitor. In freshwater drowning, inhaled water is immediately absorbed into the blood causing hemodilution. We hypothesized that this blood dilution could be observed in real time using HbI values in patients with out-of-hospital cardiac arrest (OHCA) due to freshwater drowning. METHODS: In this single-center retrospective, observational study, we examined the HbI in patients with OHCA due to freshwater drowning from April 2015 to May 2020. Patients with OHCA due to hanging were selected as a control group. RESULTS: Thirty-two patients in the freshwater drowning group and 21 in the control group were eligible for inclusion. In the freshwater drowning group, the HbI values in the return of spontaneous circulation (ROSC) group were significantly decreased in comparison to the non-ROSC group (-0.28 [IQR -0.55, -0.12] vs. -0.04 [IQR -0.16, 0.025]; p = 0.024). In the control group, the change of HbI during resuscitation in the ROSC and non-ROSC groups was not significantly different (0.11 [IQR -0.3525, 0.4225] vs. -0.02 [IQR -0.14, 0.605]; p = 0.8228). In each patient with ROSC in the freshwater drowning group, the HbI value after ROSC was significantly decreased in comparison to before ROSC (1.2±0.5 vs. 0.9±0.5]; p = 0.0156). In contrast, this difference was not observed in patients with an ROSC in the control group (3.7±1.3 vs. 3.8±1.4]; p = 0.7940). CONCLUSION: Blood dilution induced by freshwater drowning might be detected in real time using the HbI. To prove the validity of this research's result, further prospective large study is needed.

Usefulness of simultaneous measurement of brain and muscle regional oxygen saturation in shock patients: A report of three cases.

The regional oxygen saturation (rSO2) values of brain and muscle tissues can be measured simultaneously even if blood pressure cannot be measured due to circulatory failure associated with shock and may continuously reflect the oxygen supply-demand balance.

Effectiveness of near-infrared spectroscopy-guided continuous chest compression resuscitation without rhythm check in patients with out-of-hospital cardiac arrest: The prospective multicenter TripleCPR 16 study.

BACKGROUND: The proportion of adult patients with return of spontaneous circulation (ROSC) following out-of-hospital cardiac arrest (OHCA) remains unchanged since 2012. A better resuscitation strategy is needed. This study evaluated the effectiveness of a regional cerebral oxygen saturation (rSO2)-guided resuscitation protocol without rhythm check based on our previous study. METHODS: Because defibrillation is the definitive therapy that should be performed without delay for shockable rhythm, the study subjects were OHCA patients with non-shockable rhythm on hospital arrival at three emergency departments. They were divided into three groups based on their baseline rSO2 value (%): ≥50, ≥40 to <50, or <40. Continuous chest compression without rhythm checks was performed for 16 minutes or until a maximum increase in rSO2 of 10%, 20%, or 35% was achieved in each group, respectively. This intervention cohort was compared with a historical control cohort regarding the probability of ROSC using inverse probability of treatment weighting (IPTW) with propensity score. RESULTS: The control and intervention cohorts respectively included 86 and 225 patients. The rate of ROSC was not significantly different between the groups (adjusted OR 0.91 [95% CI, 0.64-1.29], P = 0.60), but no serious adverse events occurred. Sensitivity analyses 1 and 2 showed a significant difference or positive tendency for higher probability of ROSC (adjusted OR 1.63 [95% CI, 1.22-2.17], P < 0.001) (adjusted OR 1.25 [95% CI, 0.95-1.63], P = 0.11). CONCLUSIONS: This trial suggested that a new cardiopulmonary resuscitation protocol with different rhythm check timing could be created using the rSO2 value. Clinical trial number: UMIN000025684.

Pre-hospital portable monitoring of cerebral regional oxygen saturation (rSO2) by ambulance personnel during cardiopulmonary resuscitation: A prospective observational analysis of 87 cases in Osaka city, Japan.

BACKGROUND: Regional cerebral oxygen saturation (rSO2) is a non-invasive method of measuring cerebral perfusion; However, serial changes in cerebral rSO2 values among out-of-hospital cardiac arrest (OHCA) patients in pre-hospital settings have not been sufficiently investigated. We aimed to investigate the association between the serial change in rSO2 pattern and patient outcome. METHODS: We evaluated rSO2 in OHCA patients using portable monitoring by emergency life-saving technicians (ELTs) from June 2013 to December 2019 in Osaka City, Japan. We divided the patterns of serial of rSO2 change into type 1 (increasing pattern) and type 2 (non-increasing pattern). Patients in whom measurement started after return of spontaneous circulation (ROSC) were excluded. The outcome measures were 'Prehospital ROSC', 'Alive at admission', '1-month survival' and 'Cerebral Performance Category (CPC) 1 or 2'. RESULTS: Eighty-seven patients were eligible for this analysis (type 1: n = 40, median age: 80.5 [IQR: 72-85.5] years, male: n = 20 [50.0%]; type 2: n = 47, 81 [72-85.5] years, male: n = 28 [59.6%]). In a multivariable logistic regression adjusted for confounding factors, outcomes of 'Prehospital ROSC' and 'Alive at admission' were significantly higher in type 1 than type 2 pattern (11/40 [27.5%] vs. 2/47 [4.26%], AOR 5.67, 95% CI 1.04-30.96, p < 0.045 and 17/40 [42.5%] vs. 6/41 [12.8%], AOR 3.56, 95% CI 1.11-11.43, p < 0.033). There was no significant difference in '1-month survival' and 'CPC 1 or 2' between patterns. CONCLUSION: Type 1 (increasing pattern) was associated with 'Prehospital ROSC' and 'Alive at admission'. Pre-hospital monitoring of cerebral rSO2 might lead to a new resuscitation strategy.

Original experimental rat model of blast-induced mild traumatic brain injury: a pilot study.

OBJECTIVE: Diagnosing blast-induced mild traumatic brain injury (mTBI) is difficult due to minimal imaging findings. This study aimed to establish a rat model of behavioral abnormality caused by blast-induced mTBI and detect new findings for therapeutic intervention. METHODS: We used a bench-top blast wave generator with the blast wave exiting through a 20-mm I.D. nozzle aimed at the focused target. The blast wave was directed at the head of male Wistar rats under general anesthesia positioned prone 2.5 cm below the nozzle. Peak shock wave pressure was 646.2 ± 70.3 kPa. RESULTS: After blast injury, mTBI rats did not show the findings of brain hemorrhage or contusion macroscopically and on hematoxylin-eosin-stained frozen sections but did show anorexia and weight loss in the early post-injury phase. Behavioral experiments revealed short-term memory impairment at 2 weeks and depression-like behavior at 2 and 6 weeks. Diffusion-weighted ex vivo MRI showed high-intensity areas in layers of the bilateral hippocampus. Immunohistochemical analysis revealed accumulation of reactive microglia and GFAP-positive astrocytes in the same region and loss of NeuN-positive neurons in the hippocampal pyramidal cell layer. CONCLUSIONS: This model can reflect the pathophysiology of blast-induced mTBI and could potentially be used to develop therapeutic interventions in the future.

Abdominal angiography is associated with reduced in-hospital mortality among pediatric patients with blunt splenic and hepatic injury: A propensity-score-matching study from the national trauma registry in Japan.

PURPOSE: The aim of this study was to assess the association between the implementation of abdominal angiography and outcome among pediatric patients with blunt splenic or hepatic injury. METHODS: This was a retrospective observational study, with a study period of 14 years, from January 2004 to December 2017. Blunt-trauma patients with splenic or hepatic injury who were less than 19 years old were included in this study. We used propensity-score-(PS) matching analysis to assess the relationship between abdominal angiography and in-hospital mortality. RESULTS: In total, 639 patients were eligible for analysis, with 257 patients included in the abdominal-angiography group and 382 patients in the no-abdominal-angiography group. After PS matching, 224 patients from each group were selected. In the PS matched patients, in-hospital mortality was lower in the abdominal-angiography group than in the no-abdominal-angiography group (4.9% vs. 11.2%, odds ratio 0.416, 95% confidence interval 0.177-0.903). CONCLUSION: In this population, the implementation of abdominal angiography was significantly associated with lower in-hospital mortality among pediatric patients with blunt splenic or hepatic injury compared with nonimplementation of abdominal angiography. TYPE OF STUDY: Prognosis study. LEVEL OF EVIDENCE: III.

Near-Infrared Spectroscopy Assessments of Regional Cerebral Oxygen Saturation for the Prediction of Clinical Outcomes in Patients With Cardiac Arrest: A Review of Clinical Impact, Evolution, and Future Directions.

Despite three decades of advancements in cardiopulmonary resuscitation (CPR) methods and post-resuscitation care, neurological prognosis remains poor among survivors of out-of-hospital cardiac arrest, and there are no reliable methods for predicting neurological outcomes in patients with cardiac arrest (CA). Adopting more effective methods of neurological monitoring may aid in improving neurological outcomes and optimizing therapeutic interventions for each patient. In the present review, we summarize the development, evolution, and potential application of near-infrared spectroscopy (NIRS) in adults with CA, highlighting the clinical relevance of NIRS brain monitoring as a predictive tool in both pre-hospital and in-hospital settings. Several clinical studies have reported an association between various NIRS oximetry measurements and CA outcomes, suggesting that NIRS monitoring can be integrated into standardized CPR protocols, which may improve outcomes among patients with CA. However, no studies have established acceptable regional cerebral oxygen saturation cut-off values for differentiating patient groups based on return of spontaneous circulation status and neurological outcomes. Furthermore, the point at which resuscitation efforts can be considered futile remains to be determined. Further large-scale randomized controlled trials are required to evaluate the impact of NIRS monitoring on survival and neurological recovery following CA.

Clinical and Angiographic Features of Patients With Out-of-Hospital Cardiac Arrest and Acute Myocardial Infarction.

BACKGROUND: Sudden cardiac arrest is a serious complication of acute myocardial infarction (MI). Although in-hospital mortality from MI has decreased, the mortality of MI patients complicated with out-of-hospital cardiac arrest (OHCA) remains high. However, the features of acute MI patients with OHCA have not been well known. OBJECTIVES: We sought to characterize the clinical and angiographic features of acute MI patients with OHCA comparing with those without OHCA. METHODS: We retrospectively analyzed 480 consecutive patients with acute MI undergoing percutaneous coronary intervention. Patients complicated with OHCA were compared with patients without OHCA. RESULTS: Of the patients, 141 (29%) were complicated with OHCA. Multivariate analysis revealed that age (odds ratio [OR]: 0.8; 95% confidence interval [CI]: 0.7 to 0.9 per 5 years; p < 0.001), estimated glomerular filtration rate (OR: 0.8; 95% CI: 0.7 to 0.8 per 10 ml/min/1.73 m2; p < 0.001), peak creatine kinase-myocardial band (OR: 1.3; 95% CI: 1.2 to 1.4 per 102 U/l; p < 0.001), calcium-channel antagonists use (OR: 0.4; 95% CI: 0.2 to 0.7; p = 0.002), the culprit lesion at the left main coronary artery (OR: 5.3; 95% CI: 1.9 to 15.1; p = 0.002), and the presence of chronic total occlusion (OR: 2.9; 95% CI: 1.5 to 5.7; p = 0.001) were significantly associated with OHCA. CONCLUSIONS: Younger age, no use of calcium-channel antagonists, worse renal function, larger infarct size, culprit lesion in the left main coronary artery, and having chronic total occlusion were associated with OHCA.