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This paper presents a novel topology for Z-source inverters (ZSI). The new Z-Source network is based on the coupled-inductors and active switched boost. Features of the topology include high voltage boost ability, single magnetic-core, low voltage stress on the active switch, and capacitors. The principles of operation, analysis, voltage and current equations of each component, and the converter voltage gain in the steady-state are presented. A comparison with other topologies has also been performed to determine the advantages and disadvantages of the proposed ZSI. Finally, experimental results of the laboratory prototype are presented to confirm the performance of the proposed topology. [ABSTRACT FROM AUTHOR]

Background: Traumatic brain injury (TBI) is one of the leading causes of disability and death worldwide. Most TBI cases occur in older people, because they are at a higher risk of accidental falling. As the population ages, the use of anticoagulants is increasing. Some serious complications of TBI, such as intracranial hemorrhage (ICH), may occur even in mild cases. According to the current guidelines regarding managing mild TBI patients, a CT head scan is recommended for all patients receiving anticoagulation. We aim to assess the incidence of ICH in patients with mild TBI taking oral anticoagulants. Methods: Our systematic review and meta-analysis were performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist. The protocol was registered in PROSPERO (CRD42024503086). Twenty-eight studies evaluating patients with a mild TBI from ten countries with a total sample size of 11,172, 5671 on DOACs, and 5501 on VKAs were included in our meta-analysis. Results: The random-effects overall incidence of ICH among oral anticoagulated patients with mild TBI was calculated to be 9.4% [95% CI 7.2–12.1%, I2 = 89%]. The rates of immediate ICH for patients taking DOACs and VKAs were 6.4% and 10.5%, respectively. The overall rate of immediate ICH in anticoagulated mild TBI patients was 8.5% [95% CI 6.6–10.9%], with a high heterogeneity between studies (I2 = 88%). Furthermore, the rates of delayed ICH in patients with mild TBI taking DOACs and VKAs were 1.6% and 1.9%, respectively. The overall incidence of delayed ICH among oral anticoagulated mild TBI patients was 1.7% [95% CI 1–2.8%, I2 = 79%]. The overall rate of ICH among mild TBI patients taking DOAC was calculated to be 7.3% [95% CI 5.2–10.3%], with significant heterogeneity between studies (I2 = 79%). However, the overall ICH rate is higher in patients who take only VKAs 11.3% [95% CI 8.6–14.7%, I2 = 83%]. Patients on DOACs were at lower risk of ICH after mild TBI compared to patients on VKAs (OR = 0.64, 95% CI 0.48–0.86, p < 0.01, I2 = 28%). Conclusion: Our meta-analysis confirms the need for performing brain CT scan in patients with mild TBI patients who receive oral anticoagulants before injury. Due to limited data, further multi-center, prospective studies are warranted to confirm the true incidence of traumatic ICH in patients on anticoagulants. [ABSTRACT FROM AUTHOR]

In this paper, an interleaved DC–DC step-up converter with improved characteristics based on a voltage multiplier rectifier is presented. The proposed converter is presented and analyzed for two different operating duty regions including operating region 1 (0 < D ≤ 0.5), and operating region 2 (0.5 ≤ D < 1). This converter can be used in various applications such as energy storage, electric vehicles, and renewable energy systems. This converter is composed of two stages: an interleaved boost stage and a voltage multiplier rectifier stage, which collectively forms its general structure. The interleaved boost stage is a type of two-phase boost converter that transforms the input DC voltage into a high-frequency AC square waveform. This waveform can be readily filtered using smaller capacitors. The square-shaped voltage waveform from the interleaved boost stage is rectified and converted to a high DC voltage by the Voltage Multiplier Rectifier (VMR) stage. The operating regions, the evaluation of the steady-state condition, the voltage gain of the proposed converter's parasitic and ideal models as well as its losses and efficiency analysis have been evaluated. The proposed converter has an efficiency of 97% at the output power of 150 W. The proposed converter is simulated to convert a voltage of 25–159.5 V and to validate the mathematical relationships and simulation results, a laboratory prototype has been developed. The simulation and experimental results show the precision of the performance of the proposed interleaved boost converter. [ABSTRACT FROM AUTHOR]

Background: One of the most critical issues in patients suffering from traumatic brain injury (TBI) is protecting the airway and attempting to keep a secure airway. It is evident that tracheostomy in patients with TBI after 7–14 days can have favorable outcomes if the patient cannot be extubated; however, some clinicians have recommended early tracheostomy before 7 days. Methods: A retrospective cohort of inpatient study participants was queried from the National Inpatient Sample to include patients with TBI between 2016 and 2020 undergoing tracheostomy and outcomes between the two groups of early tracheostomy (ET) (< 7 days from admission) and late tracheostomy (LT) (≥ 7 days from admission) were compared. Results: We reviewed 219,005 patients with TBI, out of whom 3.04% had a tracheostomy. Patients in the ET group were younger than those in the LT group (45.02 ± 19.38 years old vs. 48.68 ± 20.50 years old, respectively, p < 0.001), mainly men (76.64% vs. 73.73%, respectively, p = 0.01), and mainly White race (59.88% vs. 57.53%, respectively, p = 0.33). The patients in the ET group had a significantly shorter length of stay as compared with those in the LT group (27.78 ± 25.96 days vs. 36.32 ± 29.30 days, respectively, p < 0.001) and had a significantly lower hospital charge ($502,502.436 ± 427,060.81 vs. $642,739.302 ± 516,078.94 per patient, respectively, p < 0.001). The whole TBI cohort mortality was reported at 7.04%, which was higher within the ET group compared with the LT group (8.69% vs. 6.07%, respectively, p < 0.001). Patients in the LT had higher odds of developing any infection (odds ratio [OR] 1.43 [1.22–1.68], p < 0.001), emerging sepsis (OR 1.61 [1.39–1.87], p < 0.001), pneumonia (OR 1.52 [1.36–1.69], p < 0.001), and respiratory failure (OR 1.30 [1.09–1.55], p = 0.004). Conclusions: This study shows that ET can provide notable and significant benefits for patients with TBI. Future high-quality prospective studies should be performed to investigate and shed more light on the ideal timing of tracheostomy in patients with TBI. [ABSTRACT FROM AUTHOR]

In this paper, a quadruple boost switched-capacitor multi-level inverter is proposed. The proposed structure utilizes a DC source, 11 switches, and a diode to achieve 17-level output voltage levels. This structure consists of three capacitors with the ability for self-balancing voltages. The capacitors achieve automatic voltage balancing through a series/parallel connection with the input voltage source. To control the switching pulses of the switches, level-shifted pulse width modulation (LS-PWM) strategy has been employed. A comparative evaluation has been performed between the proposed structure and structures presented in recent articles, considering various parameters such as voltage gain, number of DC sources, number of semiconductor devices, maximum blocking voltage (MBV), and total standing voltage (TSV). Considering this comparison, the lower number of semiconductor devices for generating a 17-level output with suitable voltage gain, and especially the cost-effectiveness of the structure, are the main advantages of the proposed configuration. In addition, a soft charging method has been employed to limit the inrush current of capacitors. Moreover, the power losses of the proposed structure have been investigated, indicating its acceptable efficiency. Finally, for the analysis and validation of the proposed structure's performance, an experimental prototype has been implemented and evaluated under various conditions. The results indicate satisfactory performance of the proposed structure under various stable and dynamic operating conditions. [ABSTRACT FROM AUTHOR]

In this paper, a new topology is introduced for capacitor-based multi-level inverters. The proposed topology is based on combination of two Cross-Square-Switched T-Type inverters. This structure can be generalized in two modular and cascaded modes. In the cascaded mode, higher voltage levels are produced with low power switches. The main features of the proposed topology include the level generation without the utilization of the H-bridge module, the low number of switching components, a lower number of DC voltage sources, and low total blocking voltage. Besides, in the proposed topology, the number of conducting switches in the current path for each different voltage level is low, which leads to a conduction loss decrement. The loss simulations are performed, and the results are presented. A study provides a detailed comparison of the proposed topology in terms of various parameters. In this paper, the nearest level modulation switching, which is low-frequency switching, is utilized to generate voltage levels. To confirm the performance of the proposed topology, a simulation was performed with MATLAB/Simulink software, and a laboratory sample was implemented. Comparative results, simulation results, and implementation results indicate the appropriate performance of the proposed structure in different steady-state and dynamic conditions. [ABSTRACT FROM AUTHOR]

Background: Takotsubo cardiomyopathy (TC) is a commonly observed complication among patients with intracerebral hemorrhage (ICH); however, the incidence of TC in patients with ICH have not been investigated yet. The goal of this study was to examine the incidence of TC in ICH and identify its risk factors, incidence rate, and outcomes of TC in patients with ICH in a US nationwide scale. Methods: Data for patients with ICH between the years of 2015 and 2018 were extracted from the Nationwide Inpatient Sample and stratified based on the diagnosis of TC. Results: Our results showed that the incidence rate of TC in ICH discharges was 0.27% (95% confidence interval [CI] 0.24–0.31). The mean age of patients with ICH developing TC was 66.28 years ± 17.11. There were significantly more women in the TC group, with an odds ratio (OR) of 3.65 (95% CI 2.63–5.05). Acute myocardial infarction (OR 7.91, 95% CI 5.80–10.80) was significantly higher in the TC group. The mortality rate of patients with ICH who had TC was significantly higher (33.48%, p < 0.0001). Length of stay (mean days; 15.72 ± 13.56 vs. 9.56 ± 14.10, p < 0.0001) significantly increased in patients with ICH who had TC. Patients with intraventricular ICH (OR 2.46, 95% CI 1.88–3.22) had the highest odds of TC. Conclusions: Takotsubo cardiomyopathy is associated with a higher mortality, longer hospitalization period, and more acute myocardial infarctions in patients with ICH. It is illustrated that intraventricular ICH is associated with higher odds of TC. [ABSTRACT FROM AUTHOR]

Background: The principal aim of this study was to determine the prevalence of intracranial pressure (ICP) monitoring and intracranial hypertension (IHT) in patients treated for moderate traumatic brain injury (TBI). A secondary objective was to assess factors associated with ICP monitoring. Methods: We conducted a systematic review of the literature to identify studies that assessed ICP monitoring in moderate TBI. The meta-analysis was performed by using a random-effects model. Results: A total of 13 studies comprising 116,714 patients were pooled to estimate the overall prevalence of ICP monitoring and IHT (one episode or more of ICP > 20 mm Hg) after moderate TBI. The prevalence rate for ICP monitoring was 18.3% (95% confidence interval 8.1–36.1%), whereas the proportion of IHT was 44% (95% confidence interval 33.8–54.7%). Three studies were pooled to estimate the prevalence of ICP monitoring according to Glasgow Coma Scale (GCS) (≤ 10 vs. > 10). ICP monitoring was performed in 32.2% of patients with GCS ≤ 10 versus 15.2% of patients with GCS > 10 (p = 0.59). Both subgroups were highly heterogeneous. We found no other variables associated with ICP monitoring or IHT. Conclusions: The prevalence of ICP monitoring in moderate TBI is low, but the prevalence of IHT is high among patients undergoing ICP monitoring. Current literature is limited in size and quality and does not identify factors associated with ICP monitoring or IHT. Further research is needed to guide the optimal use of ICP monitoring in moderate TBI. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated the usefulness of cardiac troponin I (cTn) levels in predicting adverse clinical outcomes of patients with anerusmal subarachnoid hemorrhage (aSAH). However, it remains unclear whether cTn levels can be a useful factor in predicting adverse neurologic and cardiovascular outcomes regarding follow-up duration. The study aimed to evaluate the clinical value of cTn elevation among patients with aSAH. A systematic literature search was performed in PubMed and Cochrane to collect original studies that compared the adverse outcomes in patients with aSAH who had elevated cTn levels and those who did not have elevated cTn levels. Data on patient demographics and outcome measurements (mortality, major disability, delayed cerebral ischemia, cardiac dysfunction, and pulmonary edema) were extracted. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were computed by fitting a random effects model. A total of 4,117 patients with aSAH were included in the meta-analysis. Elevated cTn levels was associated with a higher all-cause mortality (OR 3.64; 95% CI 2.68–4.94; I2 = 22.05%), poor major disability (OR 2.27; 95% CI 1.5–3.37; I2 = 52.07%), delayed cerebral ischemia (OR 2.10; 95% CI 1.46–3.03; I2 = 13.80%), cardiac dysfunction (OR 9.20; 95% CI 4.31–19.60; I2 = 39.89), and pulmonary edema (OR 10.32; 95% CI 5.64–18.90; I2 = 0.00%). Additionally, elevated cTn levels was associated with higher mortality in prospective studies (OR 3.66; 95% CI 2.61–5.14) as well as when compared with studies with short-term and long-term follow-up periods. Patients with aSAH who had elevated cTn levels also tended to experience poor short-term major disability (OR 2.36; 95% CI 1.48–3.76). Among patients with aSAH, elevated cTn levels was associated with higher mortality and adverse neurologic and cardiovascular outcomes. Given its clinical value, cardiac troponin levels may be included in the assessment of patients withs aSAH. [ABSTRACT FROM AUTHOR]

In this paper, a novel Cascaded H-Bridge (CHB)-based multilevel inverter for symmetric/asymmetric configurations is presented. The proposed MLI can be utilized in medium-voltage applications such as electrical machine drives as well as grid connection of renewable energy resources. The proposed structure uses fewer count of semiconductor devices at the same voltage level in comparison with classic and advanced structures. Cascaded connection of the proposed basic cells leads to reduce complexity and increase efficiency of the proposed structure. In order to investigate the capability and superiority of the proposed structure, a comprehensive comparison is conducted between this structure and the advanced ones in terms of efficiency, switch and gate driver count, and total blocking voltage (TBV). The fundamental frequency switching method is employed to generate proper switching pulses. The performance of the proposed multilevel inverter is investigated by simulating in MATLAB/Simulink environment. The experimental implementation for proposed 15-level symmetric and 33-level asymmetric structures validates the correctness of simulation results. [ABSTRACT FROM AUTHOR]

The NIS is mainly based on the ICD codes that the clinicians selected for their patients, and it is essentially based on the clinical workups that they have done for the patients to come up with these diagnoses, such as TC and ICH. As we have mentioned in our article, specifically in the Methods section, the I International Classification of Diseases, Tenth Revision i (ICD-10) diagnosis codes were used to include patients with ICH and a coexisting diagnosis of TC. In your letter to the editor, it is commented that our article did not mention the basis of inclusion criteria to select the patients with takotsubo cardiomyopathy (TC). [Extracted from the article]

Objective: Multiple studies have shown worse outcomes in patients admitted for medical and surgical conditions on the weekend. However, past literature analyzing this "weekend effect" on subarachnoid hemorrhage (SAH) found no significant increase in mortality. This study utilizes more recent data to re-evaluate the association between weekend admission and mortality of patients hospitalized for SAH.Methods: This retrospective cohort study queried the SAH patients in the Nationwide Inpatient Sample (NIS) database who were discharged from 2006 through 2014 during the weekend.Results: Of the 54,703 admissions for SAH identified during the study period, 14,821 (27.1%) occurred over the weekend. Patients admitted over the weekend had a mean age of 59.2 years and were most likely to be female (59.6%), to be white (62.9%), located in the south region of the USA (40.1%), and be admitted to a teaching hospital (74.4%). When compared directly to weekday admissions, patients admitted over the weekend had higher odds of in-hospital mortality (odds ratio 1.07; confidence interval 95%, 1.02-1.12). There was no significant difference shown in the rate patients get surgical clipping versus endovascular coiling (p = 0.28) or the amount of time between admission to procedure for clipping (p = 0.473) or coiling (p = 0.255) on the weekend versus a weekday.Conclusion: Based on our findings, the likelihood of the in-hospital mortality was higher for patients admitted over the weekend. However, the characteristics of the study, primarily observational, prevent us arriving at an accurate conclusion about why this occurs; hence, we believe it is an important starting point to consider for future research. [ABSTRACT FROM AUTHOR]

In this paper, an effective numerical method to solve the Cauchy type singular Fredholm integral equations (CSFIEs) of the first kind is proposed. The collocation technique based on Bernstein polynomials is used for approximation the solution of various cases of CSFIEs. By transforming the problem into systems of linear algebraic equations, we see that this approach is computationally simple and attractive. Then the approximate solution of the problem in truncated series form is obtained by using the matrix form of this method. Convergence and error analyses of the presented method are mentioned. Finally, numerical experiments show the validity, accuracy, and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Evidence for the association and the increased risk of stroke with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) is growing. Recent studies have reported on HIV infection as a potent risk factor for intracerebral hemorrhage (ICH). We used the pooled results from case-control studies to conduct a systematic review and a meta-analysis in order to evaluate the risk of ICH with HIV/AIDS. Our systematic review and meta-analysis was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses algorithm of all available case-control studies that reported on the risk of ICH in patients with HIV/AIDS. Five eligible studies were identified, totaling 5,310,426 person-years studied over various periods that ranged from 1985 to 2010. There were a total of 724 cases of ICH, 138 with HIV/AIDS. HIV-infected ICH patients were in average younger. Pooled crude incidence rate ratio (IRR) for ICH in HIV/AIDS patients was 3.40 (95 % confidence intervals [CI] 1.44-8.04; p = 0.005, random-effects model). Clinical AIDS was associated with a higher IRR of ICH (11.99, 95 % CI 2.84-50.53; p = 0.0007) than HIV+ status without AIDS (1.73, 95 % CI 1.39-2.16; p < 0.0001). Patients with CD4 lymphocyte count <200 cells/mm were similarly at a higher risk. Antiretroviral therapy did not seem to increase the risk of ICH. The available evidence suggests that HIV/AIDS is an important risk factor for ICH, particularly in younger HIV-infected patients and those with advanced disease. [ABSTRACT FROM AUTHOR]

Background: Hypoalbuminemia has been identified as a predictor of morbidity and mortality in critically ill patients. There is very little data on the significance and the prognostic value of hypoalbuminemia in patients with aneurysmal subarachnoid hemorrhage (aSAH). This study analyzed the impact of hypoalbuminemia on patient presentation, complications, and outcomes.Methods: Records of patients admitted with aSAH were examined. Data on baseline characteristics, prevalence of delayed cerebral ischemia, and discharge outcomes were collected. Multivariable logistic regression analysis was performed to assess for associations.Results: One-hundred and forty-two patients comprised the study cohort (mean age 54.6 ± 13.4), among which 45 (31.5 %) presented with hypoalbuminemia. No difference in baseline characteristics was noted between patients with hypoalbuminemia and those with normal serum albumin. The overall hospital mortality rate was significantly higher in patients with hypoalbuminemia, compared to those with normal albumin (28.9 % vs. 11.3 %; p = 0.04). Hypoalbuminemia was neither associated with delayed cerebral ischemia nor disability at discharge, but independently associated with in-hospital death (odds ratio: 4.26, 95 % confidence interval: 1.09-16.68; p = 0.04).Conclusion: In patients with aSAH, early hypoalbuminemia is an independent predictor of hospital mortality but not disability at discharge. [ABSTRACT FROM AUTHOR]

Background: Severe traumatic brain injury is associated with a multi-systemic response and changes in metabolic demand. Patients requiring intracranial pressure monitoring or cerebrospinal fluid diversion, often signifies a greater severity of injury. For this group, the association between RBC transfusion, transfusion thresholds, and clinical recovery is unknown. In this study, we studied the association between transfusion and clinical recovery for severe traumatic brain injury patients requiring external ventricular drain or intracranial pressure monitor placement.Methods: Eighty-nine patients with a primary diagnosis of traumatic brain injury requiring implantation of either an intracranial pressure monitor or external ventricular drainage device were identified. All patients were managed in a Level 1 Trauma facility by board-certified neuro-intensive care practitioners for the course of their intensive care unit duration. The correlation between transfusion and clinical recovery, defined by change in Glasgow Coma Scale was assessed.Results: Thirty-four patients required surgical decompression, and 56.18 % of the cumulative cohort were transfused during admission. Overall, transfusion was not associated with significant clinical recovery (change in GCS > 3) for Hgb threshold of 7 mg/dL (<3, 29.03 vs. ≥3, 37.93 %; p = 0.49), nor for higher stratifications (8 mg/dL, p = 0.63; 9 mg/dL, p = 0.79, 10 mg/dL, p = 1). For patients who required transfusions at thresholds ≥8 mg/dL, there was a positive association with decreased length of hospitalization, [p = 0.01; <8 mg/dL: 22 (12-33), ≥8 mg/dL: 14 (7.75-20)] [median (IQR)]. Similarly, length of ICU stay was shorter for patients transfused at thresholds ≥9 mg/dL, (p = 0.02).Conclusions: From our studies, we demonstrate no significant clinical benefit associated with stratified transfusion goals; however, there was a decrease in length of hospitalization for patients with transfusion thresholds of Hgb ≥ 8 mg/dL. Larger, randomized controlled trials may be required to more accurately assess outcomes in this patient population. In patients admitted for primary severe traumatic brain injury, we demonstrate no significant clinical benefit associated with stratified transfusion goals; however, there was a noticeable decrease in length of hospitalization for patients with transfusion thresholds of Hgb ≥ 8 mg/dL. Larger, randomized controlled trials may be required to more accurately assess outcomes in this patient population. [ABSTRACT FROM AUTHOR]

Background: Patients with traumatic brain injuries (TBIs) have an increased risk of developing a deep vein thrombosis (DVT), but the risk of hemorrhage expansion with intracranial monitoring devices remains unknown. We sought to determine the safety of chemical DVT prophylaxis in severe TBI patients with invasive intracranial pressure monitors.Methods: We retrospectively reviewed all patients with severe TBI admitted to the neurosurgical intensive care unit of a large tertiary care center over a three-year period.Results: 155 patients were included with an incidence of DVT of 12 %. The median length of time to a stable head CT was 2 days, and the median time to initiation of chemical DVT prophylaxis was 3.6 days. The odds of DVT increased with intraparenchymal hemorrhage [OR 7.21, 95 % CI (1.43-36.47), p = 0.0169], non-White ethnicity [OR 7.86, 95 % CI (1.23-50.35), p = 0.0295], female gender [OR 13.93, 95 % CI (2.47-78.73), p = 0.0029], smoking [OR 4.32, 95 % CI (1.07-17.51), p = 0.0405], no anticoagulation [OR 25.39, 95 % CI (4.26-151.48), p < 0.001], and an IVC filter [OR 15.82, 95 % CI (3.14-79.76), p < 0.001]. Twenty-eight (18 %) of these subjects experienced in-hospital mortality. The risk of in-hospital death was significantly increased among those who did not receive anticoagulation. This study found no association between DVT formation, hemorrhage expansion, or increased risk from invasive monitoring devices between various doses of unfractionated heparin (UH) and low-molecular-weight heparin (LMWH).Conclusion: We conclude that DVT prophylaxis with either LMWH or UH is safe with intracranial pressure monitors in place. [ABSTRACT FROM AUTHOR]

Needle localization of breast lesions is commonly performed for surgical guidance when excising nonpalpable lesions. A few reports have specifically addressed complications associated with needle-localized surgical breast biopsy. We present the first reported case of delayed cardiac injury resulting from migration of a guidewire from a needle-localized breast biopsy that occurred 2 years after the procedure. The patient presented with chest pain and cardiac tamponade. It was found that a hook-wire had penetrated the pericardium and left ventricular myocardium through the aortic valve into the ascending aorta. The diagnosis was made by echocardiogram and computed axial tomography scan and subsequent surgical removal was undertaken successfully. [ABSTRACT FROM AUTHOR]

The present study is devoted to developing a computational collocation technique for solving the Cauchy singular integral equation of the second kind (CSIE-2). Although, several studies have investigated the numerical approximation solution of CSIEs, the strong singularity and accuracy of the numerical methods are still two important challenges for these integral equations. In this paper, we focus on the smooth transformation and implementation of Bessel basis polynomials (BBP). The reduction of the CSIEs-2 into a system of algebraic equations with the Gauss–Legendre collocation points simplifies this technique. The technique of performing numerical approximation of the solution is well presented and illustrated in the matrix form. Also, the convergence and error bound associated with the scheme are established. Finally, several experiments show the reliability and numerical efficiency of the proposed scheme in comparison with other methods. [ABSTRACT FROM AUTHOR]

As an incapacitated patient is unable to make decisions regarding their care, physicians turn to next-of-kin when appointing a surrogate decision-maker in the absence of an advanced directive. With the increasing complexity of modern families, physicians are facing new ethical dilemmas when choosing the individual to make end-of-life decisions for their patients. Legal definitions and hierarchies are no longer adhering to the purpose of a surrogate-decision maker, which is to maintain a patient's autonomy. Moral criteria for surrogates, which emphasize the importance of making decisions that align with the patient's desires and wishes and negate biological relationships over emotional connections, are becoming much more important. This paper explores a case study in which physicians must appoint a surrogate decision-maker for an incapacitated patient, forced to choose between a biological relationship and a strong emotional connection. [ABSTRACT FROM AUTHOR]