Acute kidney injury as a prognostic predictor of in-hospital mortality and neurological outcomes in patients after extracorporeal cardiopulmonary resuscitation.

INTRODUCTION: Extracorporeal cardiopulmonary resuscitation (ECPR) is increasingly being applied to patients with refractory cardiac arrest, but the survival rate to hospital discharge is only approximately 29%. Because ECPR requires intensive resources, it is important to predict outcomes. We therefore investigated the prognostic association between acute kidney injury (AKI) and ECPR to confirm the performance of AKI as a prognostic predictor of in-hospital mortality and neurological outcomes in ECPR. METHODS: We conducted a retrospective observational study on patients undergoing ECPR for cardiac etiology at Chonnam National University Hospital from 2015 to 2021. The group diagnosed with AKI in any KDIGO category within the first 48 h after ECPR was compared to that without AKI, and the primary outcome of the study was in-hospital mortality. RESULTS: Of 138 enrolled patients, 83 were studied. Hospital mortality occurred in 49 patients (59%), and 55 (66.3%) showed poor neurological outcomes. The AKI group displayed significantly elevated in-hospital mortality (77.8% vs 24.1%) and poor neurological outcomes (81.5% vs 37.9%) compared to the non-AKI group (p < 0.001). Regression analysis showed that AKI was associated with significantly higher rates of both in-hospital mortality (odds ratio (OR) range 10.75-12.88) and neurologic outcomes (OR range 5.9-6.22). CONCLUSIONS: There was a significant association of AKI with both in-hospital mortality and poor neurologic outcome in patients after ECPR, and AKI can be used as an early prognostic predictor in these patients.

Nanoampere-Level Piezoelectric Energy Harvesting Performance of Lithography-Free Centimeter-Scale MoS2 Monolayer Film Generators.

2D transition-metal dichalcogenides have been reported to possess piezoelectricity due to their lack of inversion symmetry; thus, they are potentially applicable as electromechanical energy harvesters. Herein, the authors propose a lithography-free piezoelectric energy harvester composed of centimeter-scale MoS2 monolayer films with an interdigitated electrode pattern that is enabled only by the large scale of the film. High-quality large-scale synthesis of the monolayer films is conducted by low-pressure chemical vapor deposition with the assistance of an unprecedented Na2 S promoter. The extra sulfur supplied by Na2 S critically passivates the sulfur vacancies. The energy harvester having a large active area of ≈18.3 mm2 demonstrates an unexpectedly high piezoelectric energy harvesting performance of ≈400.4 mV and ≈40.7 nA under a bending strain of 0.57%, with the careful adjustment of side electrodes along the zigzag atomic arrays in the two dominant domain structure. Nanoampere-level harvesting has not yet been reported with any 2D material-based harvester.

Late Awakening Is Common in Settings Without Withdrawal of Life-Sustaining Therapy in Out-of-Hospital Cardiac Arrest Survivors Who Undergo Targeted Temperature Management.

OBJECTIVES: We investigated awakening time and characteristics of awakening compared nonawakening and factors contributing to poor neurologic outcomes in out-of-hospital cardiac arrest survivors in no withdrawal of life-sustaining therapy settings. DESIGN: Retrospective analysis of the Korean Hypothermia Network Pro registry. SETTING: Multicenter ICU. PATIENTS: Adult (≥ 18 yr) comatose out-of-hospital cardiac arrest survivors who underwent targeted temperature management at 33-36°C between October 2015 and December 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We measured the time from the end of rewarming to awakening, defined as a total Glasgow Coma Scale score greater than or equal to 9 or Glasgow Coma Scale motor score equals to 6. The primary outcome was awakening time. The secondary outcome was 6-month neurologic outcomes (poor outcome: Cerebral Performance Category 3-5). Among 1,145 out-of-hospital cardiac arrest survivors, 477 patients (41.7%) regained consciousness 30 hours (6-71 hr) later, and 116 patients (24.3%) awakened late (72 hr after the end of rewarming). Young age, witnessed arrest, shockable rhythm, cardiac etiology, shorter time to return of spontaneous circulation, lower serum lactate level, absence of seizures, and multisedative requirement were associated with awakening. Of the 477 who woke up, 74 (15.5%) had poor neurologic outcomes. Older age, liver cirrhosis, nonshockable rhythm, noncardiac etiology, a higher Sequential Organ Failure Assessment score, and higher serum lactate levels were associated with poor neurologic outcomes. Late awakeners were more common in the poor than in the good neurologic outcome group (38/74 [51.4%] vs 78/403 [19.4%]; p < 0.001). The awakening time (odds ratio, 1.005; 95% CIs, 1.003-1.008) and late awakening (odds ratio, 3.194; 95% CIs, 1.776-5.746) were independently associated with poor neurologic outcomes. CONCLUSIONS: Late awakening after out-of-hospital cardiac arrest was common in no withdrawal of life-sustaining therapy settings and the probability of awakening decreased over time.

Role of electrocardiogram findings in predicting 48-h mortality in patients with traumatic brain injury.

OBJECTIVE: Electrocardiogram (ECG) patterns can change, especially in patients with central nervous system disorders such as spontaneous subarachnoid hemorrhage. However, the association between the prognosis of traumatic brain injury (TBI) and ECG findings is unknown. Therefore, this study aimed to compare and to analyze ECG findings to predict early mortality in patients with TBI. METHODS: This retrospective observational study included patients with severe trauma and TBI who were admitted to the emergency department (ED) between January 2018 and December 2020. TBI was defined as an abbreviated injury scale score of the head of ≥3. We examined ECG findings, including PR prolongation (≥ 200 ms), QRS complex widening (≥ 120 ms), corrected QT interval prolongation (QTP, ≥ 480 ms), ST-segment elevation, and ST-segment depression (STD) at ED arrival. The primary outcome was 48-h mortality. RESULTS: Of the total patients with TBI, 1024 patients were included in this study and 48-h mortality occurred in 89 patients (8.7%). In multivariate analysis, QTP (odds ratio [OR], 2.017; confidence interval [CI], 1.203-3.382) and STD (OR, 8.428; 95% CI, 5.019-14.152) were independently associated with 48-h mortality in patients with TBI. The areas under the curve (AUCs) of the revised trauma score (RTS), injury severity score (ISS), QTP, STD, and the combination of QTP and STD were 0.790 (95% CI, 0.764-0.815), 0.632 (95% CI, 0.602-0.662), 0.605 (95% CI, 0.574-0.635), 0.723 (95% CI, 0.695-0.750), and 0.786 (95% CI, 0.759-0.811), respectively. The AUC of the combination of QTP and STD significantly differed from that of ISS, QTP, and STD, but not RTS. CONCLUSION: Based on the ECG findings, QTP and STD were associated with 48-h mortality in patients with TBI.

The impact of prehospital endotracheal intubation on mortality in traumatic brain injury.

INTRODUCTION: Our study aimed to evaluate whether prehospital endotracheal intubation (ETI) affects the mortality of individuals who sustain traumatic brain injury (TBI) compared with bag-valve mask (BVM) ventilation, as well as to test the interaction effect of ETI on study outcome according to carbon dioxide level. METHODS: Our retrospective study involving patients who experienced TBI between January 2019 and December 2020. The main exposure variable was the prehospital airway management technique (ETI vs. BVM) performed by emergency medical service technicians and the primary outcome was survival at hospital discharge and the secondary outcome was good functional recovery at hospital discharge and six-month survival. We performed multivariable logistic regression analysis and interaction analysis between the prehospital airway management and blood level of carbon dioxide for adjusted odds ratios (aORs) and 95% confidence intervals (CIs). RESULTS: Of 562 eligible patients, 79 (14.1%) underwent ETI and 483 (85.9%) underwent BVM ventilation. After adjusting for possible confounders, TBI patients in the ETI group has a significantly lower likehood of survival to discharge than those in the BVM group (aOR 0.57 (0.41-0.73). In interaction analysis, the rates of survival to discharge and 6-month survival with ETI were significantly lower only in groups with hypocarbia (AOR 0.61 [95% CI 0.49-0.72] and AOR 0.82 [95% CI 0.65-0.99], respectively). CONCLUSION: Among individuals who experienced severe TBI, prehospital intubation did not have a significant effect on survival outcomes and good functional recovery. Patients exhibiting hypocarbia measured on hospital arrival demonstrated lower survival outcomes in the interaction analysis.

Diagnostic value of transthoracic echocardiography compared to electrocardiogram in predicting coronary artery stenosis among patients after cardiac arrest.

BACKGROUND: In the absence of ST-segment elevation (STE) in post-return of spontaneous circulation (ROSC) electrocardiogram (ECG), coronary angiography (CAG) is required in patients with suspected coronary artery disease (CAD). However, it is a challenge to identify patients with CAD after cardiac arrest (CA). Recent European Society of Cardiology guidelines recommends transthoracic echocardiography in patients presenting with cardiac arrest. We aimed to assess the diagnostic value of regional wall motion abnormalities (RWMAs) on transthoracic echocardiography (TTE) compared to ECG in diagnosing significant coronary artery stenosis in CA patients. METHODS: This is a retrospective, observational study of adult CA patients with presumed cardiac etiology who underwent CAG from a single tertiary care hospital. We compared the predictive value of RWMA on TTE and STE on ECG in significant stenosis of ≥70% of the coronary artery diameter. The primary outcome was significant stenosis on CAG. RESULTS: There were 145 patients included in this study and CAG revealed significant stenosis in 76 (52.4%) patients. Among the 76 patients with significant stenosis, 68 (89.5%) had RWMA on TTE and 41 (54.0%) had STE. RWMA on TTE (OR 3.67; 95% CI 1.52-8.85) was independently associated with significant stenosis. Combining both RWMA on TTE and STE on ECG improved performance in the receiver operating characteristic curve analysis (area under the curve 0.722) for predicting significant stenosis compared to using only ECG alone (p = 0.001). CONCLUSIONS: RWMAs on TTE was independently associated with significant stenosis. The RWMA and STE combination had better predictive performance than using only STE on ECG to predict significant stenosis.

Fast Beam Training Technique for Millimeter-Wave Cellular Systems with an Intelligent Reflective Surface.

The concept of an intelligent reflecting surface (IRS) has recently emerged as a promising solution for improving the coverage and energy/spectral efficiency of future wireless communication systems. However, as the number of reflecting elements in an IRS increase, the beam training protocol in IRS-assisted millimeter-wave (mmWave) cellular systems requires a large beam training time because it needs to find the best beam pairs for the link between the base station (BS) and the IRS, as well as the link between the IRS and the mobile station (MS). In this paper, a fast beam training technique for IRS-assisted mmWave cellular systems with a uniform rectangular array is proposed for detecting the best beam pairs of BS-IRS and IRS-MS links simultaneously. Two different types of beam training signals (BTSs) are proposed to distinguish simultaneously transmitted beams from the BSs in multi-cell multi-beam environments: the Zadoff-Chu sequence based BTS (ZC-BTS) and m-sequence based BTS (m-BTS). The correlation properties of ZC-BTSs and m-BTSs are analyzed in multi-cell multi-beam environments. In addition, the effect of symbol time offset on the ZC-BTS and m-BTS is analyzed. Finally, simulation results reveal that the proposed technique can significantly reduce the beam training time for IRS-assisted mmWave cellular systems.

The association between diastolic blood pressure and massive transfusion in severe trauma: a retrospective single-center study.

OBJECTIVE: To evaluate the association between diastolic blood pressure and massive transfusion in severe trauma. Method: The retrospective study was conducted at a tertiary emergency medical centre in Gwangju , Republic of Korea, and comprised data of severe trauma patients with injury severity score >15 presenting between January 2016 and December 2017. Multivariate logistic regression analysis was performed to evaluate the association between diastolic blood pressure and massive transfusion. Receiver operating characteristic curve analysis was performed to estimate the prognostic performance of diastolic blood pressure. Data was analysed using SPSS 18. RESULTS: Of the 827 patients, 64(7.7%) underwent massive transfusion. After adjusting the confounders, diastolic blood pressure was found to be an independent factor in predicting massive transfusion (odds ratio: 0.965; 95% confidence interval: 0.956-0.975). CONCLUSIONS: Initially low diastolic blood pressure was found to be an independent predictor for massive transfusion in severe trauma cases.

Cell ID and Timing Estimation Techniques for Underwater Acoustic Cellular Systems in High-Doppler Environments.

In an underwater acoustic cellular (UAC) system, underwater equipment or sensor nodes need to detect the identity of an underwater base station (UBS) and synchronise it with a serving UBS. It is known that, in an underwater acoustic channel, the temporal variability of the ocean coupled with the low speed of sound in water may induce a significant Doppler shift. In this paper, two different types of cell search techniques (CSTs) are proposed to detect the cell ID and correct timing of the UBS in UAC systems with a Doppler shift: CST based on linear frequency modulation with full bandwidth in the time domain (LFM-FT) and CST based on linear frequency modulation in the frequency domain (LFM-FF). The performances (auto-correlation, cross-correlation, ambiguity function, and cross ambiguity function) of the proposed techniques are analysed and compared with simulation results. It is demonstrated by simulation that the proposed techniques perform better than previous techniques in both AWGN and multipath channels when a Doppler shift exists. It is also shown that the LFM-FF-CST achieves the best performance in the presence of a Doppler shift and is suitable for mobile UAC systems.

Quantitative analysis of aconitine in body fluids in a case of aconitine poisoning.

Aconitine belongs to the Aconitum alkaloids and is a natural toxic substance. Aconitine has been used as a traditional medicine in East Asian culture. Today, aconitine is still in use with or without a prescription, in the Republic of Korea. Here we present a case report of accidental death due to acute aconitine poisoning. An 81-year-old woman ingested liquid that had been heat extracted from the root of the Aconitum plant; she presented to the emergency room 1 h after ingestion. Her electrocardiogram showed irregular ventricular arrhythmias including ventricular tachycardia; she progressed to cardiac arrest. Cardiopulmonary resuscitation and anti-arrhythmic drugs were administered, but the patient did not survive. An autopsy was performed 2 days postmortem. Toxicological analysis was performed, and aconitine was detected by liquid chromatography tandem mass spectrometry. The antemortem blood concentration of aconitine was 39.1 ng/ml and the concentrations of aconitine in the postmortem cardiac blood, peripheral blood, cerebrospinal fluid (CSF), pericardial fluid, and urine were 21.1 ng/ml, 28.6 ng/ml, 6.8 ng/ml, 24.1 ng/ml, and 67.4 ng/ml, respectively. This is the first forensic case report of an aconitine poisoning death in the Republic of Korea with quantitative measurement of aconitine in the antemortem blood and various postmortem body fluids. To the best of our knowledge, this is the first report of the detection of aconitine in the CSF. These data about the distribution of aconitine in the antemortem blood and various postmortem body fluids is helpful for future aconitine poisoning death cases.

Conventional Chemoembolization Plus Radiofrequency Ablation versus Surgical Resection for Single, Medium-Sized Hepatocellular Carcinoma: Propensity-Score Matching Analysis.

PURPOSE: To retrospectively compare long-term outcomes of conventional chemoembolization plus radiofrequency (RF) ablation vs those of surgical resection in patients with a single 3-5-cm hepatocellular carcinoma (HCC). MATERIALS AND METHODS: From January 2008 to December 2017, 139 of 623 patients who underwent surgical resection and 60 of 186 patients who underwent chemoembolization/RF ablation in a single center were compared with respect to local tumor progression (LTP), intrahepatic distant recurrence (IDR), disease-free survival (DFS), overall survival (OS), major complications, and hospital stay before and after propensity-score matching. RESULTS: Mean follow-up periods were similar in the chemoembolization/RF ablation and surgical resection groups (41.9 mo vs 48.4 mo). Three (5%) and 17 (28.3%) patients in the chemoembolization/RF ablation group and 12 (8.6%) and 57 (41.0%) patients in the surgical resection group showed LTP and IDR (P = .366 and P =.114, respectively). At 1, 3, and 5 years, respective DFS rates were 88.1%, 65.3%, and 49.0% for chemoembolization/RF ablation and 84.2%, 58.2%, and 46.5% for surgical resection (P = .294). Moreover, respective OS rates were 95.0%, 73.5%, and 54.0% for chemoembolization/RF ablation and 97.1%, 87.4%, and 75.0% for surgical resection (P = .055). After matching (n = 52), therapeutic outcomes remained similar (P = .370, P = .110, P = .230, and P = .760, respectively). Surgical resection was associated with higher complication rates (P = .015) and longer hospital stays (8.4 d ± 3.7 vs 16.9 d ± 7.0; P < .001). CONCLUSIONS: Conventional chemoembolization combined with RF ablation may be feasible for single 3-5-cm HCCs, with comparable therapeutic outcomes vs surgical resection and shorter hospital stays.

Combined Therapy with Transarterial Chemoembolization and Radiofrequency Ablation for Hepatocellular Carcinoma: Does the Degree of Ethiodized Oil Accumulation within the Tumor Affect the Therapeutic Efficacy?

PURPOSE: To evaluate the effects of the degree of ethiodized oil accumulation achieved by transarterial chemoembolization followed by radiofrequency (RF) ablation on the treatment efficacy for a single intermediate-sized hepatocellular carcinoma (HCC). MATERIALS AND METHODS: A total of 153 consecutive patients who underwent chemoembolization and RF ablation for a single intermediate-sized HCC (2-5 cm) were included. On the basis of the degree of ethiodized oil accumulation in HCC on cone-beam CT images, patients who underwent chemoembolization and RF ablation were classified into 2 groups: compact accumulation (≥ 75%) and noncompact accumulation (< 75%). The rates of cumulative local tumor progression (LTP), disease-free survival (DFS), and overall survival (OS) were compared between groups. RESULTS: Of the 153 patients, 89 were classified into the compact ethiodized oil accumulation group and 64 in the noncompact ethiodized oil accumulation group. There were no significant differences in patient demographic or HCC characteristics between groups except for the incidence of liver cirrhosis (P = .038) and the tumor margin morphology (P = .008). The cumulative LTP rate was significantly lower in the compact accumulation group than in the noncompact accumulation group (P = .013). There were no significant differences in the incidences of complications, DFS rates (P = .055), or OS rates (P = .184). CONCLUSIONS: The degree of ethiodized oil accumulation does not play a role in decreasing the OS or DFS rate after chemoembolization and RF ablation for intermediate-sized HCC; however, it may contribute to reducing the rate of LTP.

Intimal flap detected by three-dimensional curved multiplanar reconstruction image in isolated posterior inferior cerebellar artery dissection: a report of two cases.

BACKGROUND: Spontaneous isolated posterior inferior cerebellar artery (PICA) dissection has been reported more frequently since high-resolution vessel wall magnetic resonance imaging (HR vw-MRI) was introduced to the field. The intimal flap or double lumen, which is commonly reported to be a direct sign of the dissection, is not easily detectable on HR vw-MRI because the size of the PICA is very small and tortuous. CASE PRESENTATION: Two patients with posterior circulation ischemic stroke due to spontaneous isolated PICA dissection underwent HR vw-MRI. The curved multiplanar reconstruction image reconstructed using three-dimensional (3D) HR vw-MRI (3D curved MPR imaging) is helpful to observe tortuous blood vessels such as the PICA because it can visualize the entire vessel course in a single plane. In this report, routine HR vw-MRI revealed only an intramural hematoma in both patients. However, 3D curved MPR imaging discovered the intimal flap which was not observed on the routine HR vw-MRI. Therefore, these two patients were diagnosed with spontaneous isolated PICA dissection due to the intimal flap that was observed on the 3D curved MPR image. CONCLUSION: HR vw-MRI is useful for the early diagnosis of isolated PICA dissection. Furthermore, we believe that 3D curved MPR imaging could improve the possibility of diagnosing the dissection early because it can easily confirm direct signs such as an intimal flap or double lumen.

Electrical conductivity-based contrast imaging for characterizing prostatic tissues: in vivo animal feasibility study.

BACKGROUND: Electrical conductivity-based magnetic resonance (MR) imaging may provide unique information on tissue condition because its contrast originates from the concentration and mobility of ions in the cellular space. We imaged the conductivity of normal canine prostate in vivo and evaluated tissue contrast in terms of both the conductivity distribution and anatomical significance. METHODS: Five healthy laboratory beagles were used. After clipping the pelvis hair, we attached electrodes and placed each dog inside the bore of an MRI scanner. During MR scanning, we injected imaging currents into two mutually orthogonal directions between two pairs of electrodes. A multi spin echo pulse sequence was used to obtain the MR magnitude and magnetic flux density images. The projected current density algorithm was used to reconstruct the conductivity image. RESULTS: Conductivity images showed unique contrast depending on the prostatic tissues. From the conductivity distribution, conductivity was highest in the center area and lower in the order of the middle and outer areas of prostatic tissues. The middle and outer areas were, respectively, 11.2 and 25.5% lower than the center area. Considering anatomical significance, conductivity was highest in the central zone and lower in the order of the transitional and peripheral zones in all prostates. The transitional and peripheral zones were, respectively, 7.5 and 17.8% lower than the central zone. CONCLUSIONS: Current conductivity-based MR imaging can differentiate prostatic tissues without using any contrast media or additional MR scans. The electrical conductivity images with unique contrast to tissue condition can provide a prior information on tissues in situ to be used for human imaging.

Tuberculum sellae meningioma with possible tacrolimus neurotoxicity manifesting as manic-like psychosis after kidney transplantation.

BACKGROUND: Although kidney transplantation is the best treatment option for chronic kidney disease, the accompanying immunosuppressive treatment can induce severe neurotoxicity presenting, on rare occasions, as psychosis. However, a brain tumor synchronous with immunosuppressant neurotoxicity has never been reported in a kidney transplant recipient. Herein, we report the first case of possible tacrolimus neurotoxicity with a meningioma manifesting as manic-like psychosis after kidney transplantation. CASE PRESENTATION: A 63-year-old male presenting with acute psychotic mania was admitted to a psychiatric ward approximately 2 years after kidney transplantation. On brain magnetic resonance imaging, a tuberculum sellae meningioma was found, and hyperintense white matter lesions with possible tacrolimus-induced neurotoxicity were seen on fluid-attenuated inversion recovery images. Interestingly, the patient showed no visual field defects, and his blood tacrolimus concentration was within therapeutic ranges. After 3 weeks of adjunctive treatment with blonanserin, most of the symptoms had abated. CONCLUSIONS: The present case highlights the fact that neuroimaging studies are necessary to investigate underlying causes, as well as immunosuppressant neurotoxicity, which should all be considered when atypical psychiatric symptoms develop after organ transplantation. Further, this case suggests that the additional use of atypical antipsychotics while maintaining immunosuppressants may be effective for manic-like psychotic symptoms secondary to possible immunosuppressant neurotoxicity synchronous with a meningioma.

Association of plasma neutrophil gelatinase-associated lipocalin with acute kidney injury and clinical outcome in cardiac arrest survivors depends on the time of measurement.

PURPOSE: The optimal timing for measurement of neutrophil gelatinase-associated lipocalin (NGAL) level to predict acute kidney injury (AKI) and prognosis in cardiac arrest (CA) survivors has not been elucidated. We aimed to compare the diagnostic and prognostic performance of NGAL levels after return of spontaneous circulation (ROSC) and at 48 h after CA. METHODS: We included 231 adult cardiac arrest survivors who underwent targeted temperature management between May 2013 and December 2016. The primary outcome was stage 2 and 3 AKI (high stage AKI), and the secondary outcomes were in-hospital mortality and neurologic outcome. Sixty-one (26.4%) developed high stage AKI, 50 (21.6%) died, and 152 (65.8%) had a poor neurologic outcome. RESULTS: NGAL level at 48 h (0.876; 95% confidence interval [CI], 0.826-0.916) had a higher area under receiver operating characteristic curve than NGAL level after ROSC (0.694; 95% CI, 0.631-0.753). Both NGAL levels were independently associated with high stage AKI. NGAL level at 48 h (1.001; 95% CI, 1.000-1.002) remained a significant predictor for in-hospital mortality, while neither of the NGAL levels were independently associated with neurologic outcome. CONCLUSIONS: NGAL at 48 h after CA seems to be a robust predictor for high stage AKI and in-hospital mortality.

Prognostic Performance Evaluation of the International Society on Thrombosis and Hemostasis and the Korean Society on Thrombosis and Hemostasis Scores in the Early Phase of Trauma.

BACKGROUND: Disseminated intravascular coagulation (DIC) contributes to poor outcome in the early phase of trauma. We aimed to analyze and compare the prognostic performances of the International Society on Thrombosis and Hemostasis (ISTH) and the Korean Society on Thrombosis and Hemostasis (KSTH) scores in the early phase of trauma. METHODS: Receiver operating characteristics analysis was used to examine the prognostic performance of both scores, and multivariate analysis was used to estimate the prognostic impact of the ISTH and KSTH scores in the early phase of trauma. The primary outcome was 24-hour mortality and the secondary outcome was massive transfusion. RESULTS: Of 1,229 patients included in the study, the 24-hour mortality rate was 7.6% (n = 93), and 8.1% (n = 99) of patients who received massive transfusions. The area under the curves (AUCs) of the KSTH and ISTH scores for 24-hour mortality were 0.784 (95% confidence interval [CI], 0.760-0.807) and 0.744 (95% CI, 0.718-0.768), respectively. The AUC of KSTH and ISTH scores for massive transfusion were 0.758 (95% CI, 0.734-0.782) and 0.646 (95% CI, 0.619-0.673), respectively. The AUCs of the KSTH score was significantly different from those of the ISTH score. Overt DIC according to KSTH criteria only, was independently associated with 24-hour mortality (odds ratio [OR], 2.630; 95% CI, 1.456-4.752). Only the KSTH score was independently associated with massive transfusion (OR, 1.563; 95% CI, 1.182-2.068). CONCLUSION: The KSTH score demonstrates a better prognostic performance for outcomes than the ISTH score in the early phase of trauma.

Successful extracorporeal life support in respiratory failure after copper sulphate ingestion.

A 44-year-old woman intentionally ingested a solution of copper sulphate. She had minimal intravascular haemolysis and methemoglobinaemia but developed acute respiratory distress syndrome (ARDS) 4 hours after acute copper sulphate poisoning. This required extracorporeal membrane oxygenation (ECMO) management in the intensive care unit. Subsequently, she improved clinically and was successfully weaned from ECMO. Acute copper sulphate poisoning can cause severe pulmonary toxicity even in the absence of other serious symptoms. Therefore, a physician treating acute copper sulphate poisoning should look out for respiratory symptoms even in the absence of other common symptoms. We suggest early initiation of venovenous ECMO in those with ARDS following copper sulphate poisoning.

Random Access for Underwater Acoustic Cellular Systems.

In this paper, a random access preamble (RAP) design technique for underwater acoustic cellular systems is proposed. After showing that the conventional RAP used in long term evolution (LTE) systems is not appropriate for underwater acoustic cellular systems, two different types of RAPs (RAP 1 and RAP 2) are proposed to detect the identity of underwater equipment/nodes (UEs) and estimate the time delay between a UE and an underwater base station (UBS) at the physical layer. RAP 1 is generated using a Zadoff-Chu (ZC) sequence where the identity of the UE is mapped to its root index, whereas RAP 2 is generated using a linear frequency modulation (LFM) waveform where the identity of the UE is mapped to its frequency sweeping parameter and frequency shifting parameter. Ambiguity functions (AFs) and cross-ambiguity functions (CAFs) of RAP 1 and RAP 2 are derived to investigate their correlation properties under the effect of time delay and Doppler shift. The performance of RAP detection is investigated by analyzing the detection probabilities and false alarm probabilities of RAP 1 and RAP 2 in a Doppler environment. By evaluating the performances of RAP 1 and RAP 2 in various situations, it is concluded that RAP 2 is more suitable for underwater acoustic cellular systems. The AF and CAF analytically obtained in this paper are shown to be similar to those obtained using experimental data.

Hybrid Beamforming for Reduction of Inter-Beam Interference in Millimeter-Wave Cellular Systems.

In millimeter-wave (mm-wave) cellular systems, beamforming antennas are necessary at both the base station (BS) and mobile station (MS) to compensate for high attenuation in mm-wave frequency bands and to extend the transmission range. The beamforming antennas also allow each BS to serve a number of MSs simultaneously, providing a substantial gain in system capacity. In space-division multiple access (SDMA) systems, the challenge is the inter-beam interference (IBI) caused by adjacent beams that are formed by the BS in the same cell and BSs in neighboring cells. The beams that are formed toward MSs in each cell may generate significant interference to MSs in neighboring cells, especially for MSs at the cell boundary. In this paper, we propose four different digital precoding techniques (Type-1, Type-2, Type-3, and Type-4) to reduce IBI in mm-wave cellular systems with a hybrid beamformer. Simulation results show that the proposed techniques can reduce the IBI in mm-wave cellular systems effectively, compared with a single-cell multiuser case.