Development and Validation of a Policy Tree Approach for Optimizing Intravenous Fluids in Critically Ill Patients with Sepsis and Acute Kidney Injury.

Purpose: Intravenous fluids are mainstay of management of acute kidney injury (AKI) after sepsis but can cause fluid overload. Recent literature shows that restrictive fluid strategy may be beneficial in some patients with AKI, however, identifying these patients is challenging. We aimed to develop and validate a machine learning algorithm to identify patients who would benefit from a restrictive fluid strategy. Methods: We included patients with sepsis who developed AKI within 48 hours of ICU admission and defined restrictive fluid strategy as receiving <500mL fluids within 24 hours after AKI. Our primary outcome was early AKI reversal within 48 hours of AKI onset, and secondary outcomes included sustained AKI reversal and major adverse kidney events (MAKE) at discharge. We used a causal forest, a machine learning algorithm to estimate individual treatment effects and policy tree algorithm to identify patients who would benefit by restrictive fluid strategy. We developed the algorithm in MIMIC-IV and validated it in eICU database. Results: Among 2,091 patients in the external validation cohort, policy tree recommended restrictive fluids for 88.2%. Among these, patients who received restrictive fluids demonstrated significantly higher rate of early AKI reversal (48.2% vs 39.6%, p<0.001), sustained AKI reversal (36.7% vs 27.4%, p<0.001) and lower rates of MAKE by discharge (29.3% vs 35.1%, p=0.019). These results were consistent in adjusted analysis. Conclusion: Policy tree based on causal machine learning can identify septic patients with AKI who benefit from a restrictive fluid strategy. This approach needs to be validated in prospective trials.

Terahertz binary computing in a coupled toroidal metasurface.

The applications of terahertz metamaterials are being actively explored in recent times for applications in high-speed communication devices, miniature photonic circuits, and bio-chemical devices because of their wide advantages. The toroidal resonance, a new type of metasurface resonance, has been examined with great interest to utilize its properties in terahertz metasurface applications. This study reports a proof of concept design of a toroidal metasurface that experimentally demonstrates binary computing operations in the terahertz frequency regime. The analog computing of binary operations is achieved by the passive tuning of distance between the split ring resonators comprising the meta-molecule. The amplitude modulation is utilized as a method of determining the Boolean logic outputs of the system. The proposed metasurface could be further optimized for high amplitude modulations and active logic gate operations using tunable materials including graphene and ITO. The proposed metasurface consists of three split-ring resonators, and the near-field coupling between the adjacent resonators dictates the Boolean operations. A multipole analysis of the scattered powers of terahertz radiation determines the toroidal excitation in the metasurface. The proposed metasurfaces experimentally define AND Boolean logic operation at 0.89 terahertz, and OR Boolean logic operation at 0.97 terahertz. Numerical simulations support the experimentally obtained results. Additionally, we numerically report the excitation of NAND operation at 0.87 THz. Such toroidal analog computing metasurfaces could find applications in digitized terahertz circuits and integrated photonic devices.

Terahertz tunable band-stop filter using topological valley photonic crystals.

In recent years, there has been a growing interest in the wideband propagation and control of terahertz (THz) radiation due to its potential for a variety of applications, such as 6G communication, sensing, and imaging. One promising approach in this area is the use of valley photonic crystals (VPCs), which exhibit properties like wider band gaps and robust propagation. In this paper, a two-dimensional dielectric silicon-air VPC is studied, which is constructed from a method of inversion symmetry breaking providing a band gap of 109.4 GHz at a mid-gap frequency of 0.376 THz. We employ an optimized bearded-stack interface to construct the VPC waveguide for wideband THz propagation along straight and Z-shaped paths. We demonstrate that a band-stop response can be achieved in a VPC by introducing periodic defects along the domain wall. Furthermore, the stop range can be tuned by varying the refractive index of the defects through incorporating liquid crystal along the domain wall of VPC. Our proposed structure and the techniques employed could be promising for the development of a band-stop filter (BSF) and other photonic components having potential applications in 6G communication and beyond.

Strong transient magnetic fields induced by THz-driven plasmons in graphene disks.

Strong circularly polarized excitation opens up the possibility to generate and control effective magnetic fields in solid state systems, e.g., via the optical inverse Faraday effect or the phonon inverse Faraday effect. While these effects rely on material properties that can be tailored only to a limited degree, plasmonic resonances can be fully controlled by choosing proper dimensions and carrier concentrations. Plasmon resonances provide new degrees of freedom that can be used to tune or enhance the light-induced magnetic field in engineered metamaterials. Here we employ graphene disks to demonstrate light-induced transient magnetic fields from a plasmonic circular current with extremely high efficiency. The effective magnetic field at the plasmon resonance frequency of the graphene disks (3.5 THz) is evidenced by a strong ( ~ 1°) ultrafast Faraday rotation ( ~ 20 ps). In accordance with reference measurements and simulations, we estimated the strength of the induced magnetic field to be on the order of 0.7 T under a moderate pump fluence of about 440 nJ cm-2.

Guidelines for the Management of Adult Acute and Acute-on-Chronic Liver Failure in the ICU: Neurology, Peri-Transplant Medicine, Infectious Disease, and Gastroenterology Considerations

To develop evidence-based recommendations for clinicians caring for adults with acute liver failure (ALF) or acute on chronic liver failure (ACLF) in the ICU. The guideline panel comprised 27 members with expertise in aspects of care of the critically ill patient with liver failure or methodology. We adhered to the Society of Critical Care Medicine standard operating procedures manual and conflict-of-interest policy. Teleconferences and electronic-based discussion among the panel, as well as within subgroups, served as an integral part of the guideline development. In part 2 of this guideline, the panel was divided into four subgroups: neurology, peri-transplant, infectious diseases, and gastrointestinal groups. We developed and selected Population, Intervention, Comparison, and Outcomes (PICO) questions according to importance to patients and practicing clinicians. For each PICO question, we conducted a systematic review and meta-analysis where applicable. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. We used the evidence to decision framework to facilitate recommendations formulation as strong or conditional. We followed strict criteria to formulate best practice statements. We report 28 recommendations (from 31 PICO questions) on the management ALF and ACLF in the ICU. Overall, five were strong recommendations, 21 were conditional recommendations, two were best-practice statements, and we were unable to issue a recommendation for five questions due to insufficient evidence. Multidisciplinary, international experts formulated evidence-based recommendations for the management ALF and ACLF patients in the ICU, acknowledging that most recommendations were based on low quality and indirect evidence.

Guidelines for the Management of Adult Acute and Acute-on-Chronic Liver Failure in the ICU: Neurology, Peri-Transplant Medicine, Infectious Disease, and Gastroenterology Considerations.

OBJECTIVES: To develop evidence-based recommendations for clinicians caring for adults with acute liver failure (ALF) or acute on chronic liver failure (ACLF) in the ICU. DESIGN: The guideline panel comprised 27 members with expertise in aspects of care of the critically ill patient with liver failure or methodology. We adhered to the Society of Critical Care Medicine standard operating procedures manual and conflict-of-interest policy. Teleconferences and electronic-based discussion among the panel, as well as within subgroups, served as an integral part of the guideline development. INTERVENTIONS: In part 2 of this guideline, the panel was divided into four subgroups: neurology, peri-transplant, infectious diseases, and gastrointestinal groups. We developed and selected Population, Intervention, Comparison, and Outcomes (PICO) questions according to importance to patients and practicing clinicians. For each PICO question, we conducted a systematic review and meta-analysis where applicable. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. We used the evidence to decision framework to facilitate recommendations formulation as strong or conditional. We followed strict criteria to formulate best practice statements. MEASUREMENTS AND MAIN RESULTS: We report 28 recommendations (from 31 PICO questions) on the management ALF and ACLF in the ICU. Overall, five were strong recommendations, 21 were conditional recommendations, two were best-practice statements, and we were unable to issue a recommendation for five questions due to insufficient evidence. CONCLUSIONS: Multidisciplinary, international experts formulated evidence-based recommendations for the management ALF and ACLF patients in the ICU, acknowledging that most recommendations were based on low quality and indirect evidence.

Genome-wide identification and molecular characterization of CRK gene family in cucumber (Cucumis sativus L.) under cold stress and sclerotium rolfsii infection.

BACKGROUND: The plant cysteine-rich receptor-like kinases (CRKs) are a large family having multiple roles, including defense responses under both biotic and abiotic stress. However, the CRK family in cucumbers (Cucumis sativus L.) has been explored to a limited extent. In this study, a genome-wide characterization of the CRK family has been performed to investigate the structural and functional attributes of the cucumber CRKs under cold and fungal pathogen stress. RESULTS: A total of 15 C. sativus CRKs (CsCRKs) have been characterized in the cucumber genome. Chromosome mapping of the CsCRKs revealed that 15 genes are distributed in cucumber chromosomes. Additionally, the gene duplication analysis of the CsCRKs yielded information on their divergence and expansion in cucumbers. Phylogenetic analysis divided the CsCRKs into two clades along with other plant CRKs. Functional predictions of the CsCRKs suggested their role in signaling and defense response in cucumbers. The expression analysis of the CsCRKs by using transcriptome data and via qRT-PCR indicated their involvement in both biotic and abiotic stress responses. Under the cucumber neck rot pathogen, Sclerotium rolfsii infection, multiple CsCRKs exhibited induced expressions at early, late, and both stages. Finally, the protein interaction network prediction results identified some key possible interacting partners of the CsCRKs in regulating cucumber physiological processes. CONCLUSIONS: The results of this study identified and characterized the CRK gene family in cucumbers. Functional predictions and validation via expression analysis confirmed the involvement of the CsCRKs in cucumber defense response, especially against S. rolfsii. Moreover, current findings provide better insights into the cucumber CRKs and their involvement in defense responses.

Robust and sustainable Mg1-xCexNiyFe2-yO4 magnetic nanophotocatalysts with improved photocatalytic performance towards photodegradation of crystal violet and rhodamine B pollutants.

This study aims at manufacturing Ce3+/Ni2+ ions doped Mg nanoferrites by the sol-gel method for the photocatalytic degradation of rhodamine B and crystal violet pollutants under visible natural sunlight. The particle size of synthesized nanoferrites was calculated through XRD, Hall-William plots, and TEM analysis, which perfectly agree with each other. FTIR study investigated the existence of stretching vibrations in M - O (metal-oxygen) complexes at the tetrahedral (A-site) and octahedral sites (B-site). The Raman spectra of synthesized nanophotocatalysts show the presence of four vibrational modes (Eg + 2T2g + A1g), providing suitable information of occupancy of Mg2+, Ce3+, Ni2+, and Fe3+ ions at the interstitial sites of undoped and Ce3+/Ni2+ doped MgFe2O4 crystal structure. The synthesized MGF3 nanophotocatalyst performs well with degradation of 97.674% crystal violet (CV) and 90.05% rhodamine B (RhB) under natural sunlight in 60 min. The experimental results showed that doped MgFe2O4 nanoferrites have a high tendency to photodegrade the RhB and CV dyes in an aqueous form. The pseudo-first-order equation reflects the best photocatalytic process kinetics and studied the feasibility of RhB and CV dyes adsorption on the doped and undoped MgFe2O4 nanoferrites. The results show good support for adsorption by the spontaneous photodegradation process. The excellent photocatalytic activity of synthesized nanoferrites under natural sunlight verifies them as a potential candidate for the photodegradation of organic dyes. Finally, the antibacterial activity of magnetic nanoferrites was examined against S. aureus and E. Coli. The studies demonstrated that synthesized magnetic nanoferrites were more effective against S. aureus.

Toroidal electromagnetically induced transparency based meta-surfaces and its applications.

The vigorous research on low-loss photonic devices has brought significance to a new kind of electromagnetic excitation, known as toroidal resonances. Toroidal excitation, possessing high-quality factor and narrow linewidth of the resonances, has found profound applications in metamaterial (MM) devices. By the coupling of toroidal dipolar resonance to traditional electric/magnetic resonances, a metamaterial analogue of electromagnetically induced transparency effect (EIT) has been developed. Toroidal induced EIT has demonstrated intriguing properties including steep linear dispersion in transparency windows, often leading to elevated group refractive index in the material. This review summarizes the brief history and properties of the toroidal resonance, its identification in metamaterials, and their applications. Further, numerous theoretical and experimental demonstrations of single and multiband EIT effects in toroidal-dipole-based metamaterials and its applications are discussed. The study of toroidal-based EIT has numerous potential applications in the development of biomolecular sensing, slow light systems, switches, and refractive index sensing.

Do high-dose corticosteroids improve outcomes in hospitalized COVID-19 patients?

Coronavirus disease 2019 (COVID-19) is characterized by dysregulated hyperimmune response and steroids have been shown to decrease mortality. However, whether higher dosing of steroids results in better outcomes has been debated. This was a retrospective observation of COVID-19 admissions between March 1, 2020, and March 10, 2021. Adult patients (≥18 years) who received more than 10 mg daily methylprednisolone equivalent dosing (MED) within the first 14 days were included. We excluded patients who were discharged or died within 7 days of admission. We compared the standard dose of steroids (<40 mg MED) versus the high dose of steroids (>40 mg MED). Inverse probability weighted regression adjustment (IPWRA) was used to examine whether higher dose steroids resulted in improved outcomes. The outcomes studied were in-hospital mortality, rate of acute kidney injury (AKI) requiring hemodialysis, invasive mechanical ventilation (IMV), hospital-associated infections (HAI), and readmissions. Of the 1379 patients meeting study criteria, 506 received less than 40 mg of MED (median dose 30 mg MED) and 873 received more than or equal to 40 mg of MED (median dose 78 mg MED). Unadjusted in-hospital mortality was higher in patients who received high-dose corticosteroids (40.7% vs. 18.6%, p < 0.001). On IPWRA, the use of high-dose corticosteroids was associated with higher odds of death (odds ratio [OR] 2.14; 95% confidence interval [CI] 1.45-3.14, p < 0.001) but not with the development of HAI, readmissions, or requirement of IMV. High-dose corticosteroids were associated with lower rates of AKI requiring hemodialysis (OR 0.33; 95% CI 0.18-0.63). In COVID-19, corticosteroids more than or equal to 40 mg MED were associated with higher in-hospital mortality.

Outcomes of Covid 19 patients-Are Hispanics at greater risk?

Disparities in outcomes exist in outcomes of coronavirus disease-19 (COVID-19). Little is known about other ethnic minorities in United States. We included all COVID-19 positive adult patients (≥18 years) hospitalized between March 1, 2020 and February 5th 2021. We compared in hospital mortality, use of intensive care unit services and inflammatory markers between non-Hispanic whites with non-White/Black Hispanic. Multivariable Cox proportional Hazard models were used to adjust for differences between the two groups. There were 4059 hospital admissions with COVID-19 in the study period. Of the 3288 White, 789 (24%) required intensive care unit (ICU) admission in comparison to 187 (24.3%) of the 770 Hispanics. Unadjusted mortality was higher in Whites than Hispanics (17.1% vs. 10.7%; p < 0.001). After adjusting for confounding variables, in-hospital mortality was not statistically different for Whites in comparison to Hispanics (hazard ratio [HR]: 0.96, 95% confidence interval [CI]: 0.76-1.21, p = 0.73). The adjusted rates of ICU transfers were significantly higher in Hispanics (HR: 1.34, 95% CI: 1.11-1.61, p = 0.002). Hispanics had significantly higher C-reactive protein, lactate dehydrogenase, and fibrinogen when compared to Whites. Hispanics as compared to Whites with COVID-19 require higher rates of ICU admission but have a similar mortality. Hispanics as compared to Whites with COVID-19 require higher rates of ICU admission but have a similar mortality.

Multiband transparency effect induced by toroidal excitation in a strongly coupled planar terahertz metamaterial.

The multiband transparency effect in terahertz (THz) domain has intrigued the scientific community due to its significance in developing THz multiband devices. In this article, we have proposed a planar metamaterial geometry comprised of a toroidal split ring resonator (TSRR) flanked by two asymmetric C resonators. The proposed geometry results in multi-band transparency windows in the THz region via strong near field coupling of the toroidal excitation with the dipolar C-resonators of the meta molecule. The geometry displays dominant toroidal excitation as demonstrated by a multipolar analysis of scattered radiation. High Q factor resonances of the metamaterial configuration is reported which can find significance in sensing applications. We report the frequency modulation of transparency windows by changing the separation between TSRR and the C resonators. The numerically simulated findings have been interpreted and validated using an equivalent theoretical model based upon three coupled oscillators system. Such modeling of toroidal resonances may be utilized in future studies on toroidal excitation based EIT responses in metamaterials. Our study has the potential to impact the development of terahertz photonic components useful in building next generation devices.

Incidence of Venous Thromboembolism and Effect of Anticoagulant Dosing in Hospitalized COVID-19 Patients.

Background: Coronavirus disease 2019 (COVID-19) is characterized by coagulopathy and thrombotic events. We examined factors associated with development of venous thromboembolism (VTE) in COVID-19 and to discern if higher dose of anticoagulation was beneficial in these patients. Methods: This study involves an observational study of prospectively collected data in the setting of a large community hospital in a rural setting in Northeast Georgia with COVID-19 between March 1, 2020 and February 5, 2021. Anticoagulation dose (none, standard, intermediate, and therapeutic dosages) was studied in adult patients (≥ 18 years). We constructed multivariable logistic regression model to examine the association of clinical characteristics with VTE. To examine the effect of dose of anticoagulation in preventing VTE, we used inverse probability weighted regression adjustment. Results: Of the 4,645 patients with COVID-19, 251 (5.4%) patients were found to have VTE. Of these, 91 had pulmonary embolism, 148 had deep venous thrombosis (DVT) and 12 had both. A total of 129 of VTE cases were diagnosed at admission. Of all admissions, 12.9% did not receive any DVT prophylaxis, 70.4% received prophylactic dose, 1.3% received intermediate dose and 15.5% received therapeutic dose. Male gender (odds ratio (OR): 1.55, 95% confidence interval (CI): 1.0 - 2.4, P = 0.04) and Black race (OR: 2.0, 95% CI: 1.2 - 3.4, P = 0.01), along with higher levels of lactate dehydrogenase (LDH) and D-dimer were associated with higher odds of developing VTE. Patients receiving steroids had lower rates of VTE (3.9% vs. 8.3%, P < 0.001). Use of intermediate or therapeutic anticoagulation was not associated with lower odds of developing VTE. However, patients on therapeutic anticoagulation had lower odds of in hospital mortality when compared to standard dose (OR: 0.47, 95% CI: 0.27 - 0.80, P = 0.006). Conclusions: In COVID-19, D-dimer and LDH can be useful in predicting VTE. Steroids appear to have some protective role in development of VTE. Therapeutic anticoagulation did not result in lower rates of VTE but was associated with in-hospital mortality.

Pivotal Role of Quantum Dots in the Advancement of Healthcare Research.

The quantum dot is a kind of nanoparticle whose dimension is smaller than the size of a typical nanoparticle ranging from tens of nanometers to a few hundredths of nanometers. The quantum mechanical behavior associated with the quantum dot displays different optical and electronic properties, enabling the quantum dot to find potential applications in a multitude of areas such as solar cells, light-emitting diodes, lasers, and biomedical applications. The objective of this investigation is to explore its fundamentals, synthesis, and applications, especially in the healthcare domain. We have discussed the quantum dot synthesis techniques using chemical methods, namely, wet-chemical methods and vapor-phase methods and plasma processing methods, namely, an ion sputtering method and plasma-enhanced chemical vapor deposition method. We have thoroughly investigated the application of quantum dots in imaging, diagnostics, and gene therapy areas. A significant outcome of this review is to propose quantum dots as a new modality in the treatment of cancer and gene therapeutics in the healthcare domain and the potentials of artificial intelligence to improve their performance via the applications of neural networks.

Does ABO Blood Groups Affect Outcomes in Hospitalized COVID-19 Patients?

BACKGROUND: Blood group type A has been associated with increased susceptibility for coronavirus disease 2019 (COVID-19) infection when compared to group O. The aim of our study was to examine outcomes in hospitalized COVID-19 patients among blood groups A and O. METHODS: This is an observational study. Kruskal-Wallis and Chi-square tests were used to compare continuous and categorical variables. Multivariable logistic regression models were used to examine association of blood groups with rates of mortality and severity of disease. All adult patients (> 18 years) admitted with COVID-19 infection between March 1, 2020 and March 10, 2021 at a large community hospital in Northeast Georgia were included. We compared mortality, severity of disease (use of mechanical ventilation, vasopressor, and acute renal failure), rates of venous thromboembolism and inflammatory markers between the blood groups. We used multivariable logistic regression model to adjust for demographical and clinical characteristics, use of COVID-19 medications and severity. RESULTS: A total of 3,563 of 5,204 admitted patients had information on blood groups. Of these, 1,301 (36.5%) were group A, 377 (10.6 %) were group B, 133 (3.7%) were group AB and 1,752 (49.2%) were group O. On adjusted analysis, there were no significant differences in rates of intensive care unit (ICU) admissions, mechanical ventilation, vasopressors, acute renal failure, venous thromboembolism and readmission rate between the blood groups A and O. In-hospital mortality was also not statistically different among the blood groups A and O (17.5% vs. 20.1%; P = 0.07). On adjusted analysis, in-hospital mortality was not lower in blood groups O (odds ratio (OR): 1.06; 95% confidence interval (CI): 0.80 - 1.40, P = 0.70). CONCLUSIONS: Once hospitalized with COVID-19 infection, blood groups A and O are not associated with increased severity or in-hospital mortality.

Characterization of sucrose non-fermenting-1 (SNF1) homologue gene in Fusarium udum WSP-V2 and its regulation by the biocontrol agent Pseudomonas fluorescens OKC.

Sucrose non-fermenting 1 (SNF1) is a protein kinase and plays an important role in the energy homeostasis of glucose repressible gene transcription. It derepresses glucose repressed genes and associated with pathogenesis and production of cell wall degrading enzymes in fungal species. In the present study, we identified and characterized SNF1 homologue FuSNF1 in the F. udum strain WSP-V2. Transcript analysis of FuSNF1 along with the MAP kinases and some cell wall degrading enzyme (CWDE) genes of F. udum during interaction with pigeonpea revealed that most MAP kinases and CWDE genes was positively correlated with the FuSNF1 gene. Interestingly, transcript accumulation of all these genes was lowered when pigeonpea seeds were bioprimed with a PGPR strain Pseudomonas fluorescens OKC. Transcript accumulation of FuSNF1 was observed from the day of inoculation and reached maximum level on day 7 in OKC non-bioprimed plants. However, transcript accumulation was low (1.5 fold) in F. udum inoculated with pigeonpea plants bioprimed with OKC. Transcript accumulation patterns of the F. udum MAP Kinases genes and CWDE genes also showed a similar trend and their transcript accumulation was lowered in the OKC bioprimed treatment. The results thus indicate a prime role of FuSNF1 in regulating pathogenicity and virulence of F. udum. The results further emphasize the importance of application of effective PGPR strains in regulating virulence of F. udum. In silico analysis of the SNF1 reference proteins from different fungal species showed that their homologue FuSNF1 is likely to be thermostable and acidic in nature.

The Number of Confirmed Cases of Covid-19 by using Machine Learning: Methods and Challenges.

Covid-19 is one of the biggest health challenges that the world has ever faced. Public health policy makers need the reliable prediction of the confirmed cases in future to plan medical facilities. Machine learning methods learn from the historical data and make predictions about the events. Machine learning methods have been used to predict the number of confirmed cases of Covid-19. In this paper, we present a detailed review of these research papers. We present a taxonomy that groups them in four categories. We further present the challenges in this field. We provide suggestions to the machine learning practitioners to improve the performance of machine learning methods for the prediction of confirmed cases of Covid-19.

Aspirin Use Is Associated With Decreased Mechanical Ventilation, Intensive Care Unit Admission, and In-Hospital Mortality in Hospitalized Patients With Coronavirus Disease 2019.

BACKGROUND: Coronavirus disease-2019 (COVID-19) is associated with hypercoagulability and increased thrombotic risk in critically ill patients. To our knowledge, no studies have evaluated whether aspirin use is associated with reduced risk of mechanical ventilation, intensive care unit (ICU) admission, and in-hospital mortality. METHODS: A retrospective, observational cohort study of adult patients admitted with COVID-19 to multiple hospitals in the United States between March 2020 and July 2020 was performed. The primary outcome was the need for mechanical ventilation. Secondary outcomes were ICU admission and in-hospital mortality. Adjusted hazard ratios (HRs) for study outcomes were calculated using Cox-proportional hazards models after adjustment for the effects of demographics and comorbid conditions. RESULTS: Four hundred twelve patients were included in the study. Three hundred fourteen patients (76.3%) did not receive aspirin, while 98 patients (23.7%) received aspirin within 24 hours of admission or 7 days before admission. Aspirin use had a crude association with less mechanical ventilation (35.7% aspirin versus 48.4% nonaspirin, P = .03) and ICU admission (38.8% aspirin versus 51.0% nonaspirin, P = .04), but no crude association with in-hospital mortality (26.5% aspirin versus 23.2% nonaspirin, P = .51). After adjusting for 8 confounding variables, aspirin use was independently associated with decreased risk of mechanical ventilation (adjusted HR, 0.56, 95% confidence interval [CI], 0.37-0.85, P = .007), ICU admission (adjusted HR, 0.57, 95% CI, 0.38-0.85, P = .005), and in-hospital mortality (adjusted HR, 0.53, 95% CI, 0.31-0.90, P = .02). There were no differences in major bleeding (P = .69) or overt thrombosis (P = .82) between aspirin users and nonaspirin users. CONCLUSIONS: Aspirin use may be associated with improved outcomes in hospitalized COVID-19 patients. However, a sufficiently powered randomized controlled trial is needed to assess whether a causal relationship exists between aspirin use and reduced lung injury and mortality in COVID-19 patients.