Search Results (1,949)

Background and Aim: Mechanical ventilatory support is often required in patients with acute respiratory distress syndrome (ARDS). However, early differences in ventilatory mechanics and severity scores between COVID-19 and non-COVID-19 ARDS patients remain unclear. This study aimed to compare respiratory parameters and clinical severity scores in COVID-19 and non-COVID-19 ARDS patients managed in the emergency department (ED) and evaluate their association with in-hospital mortality. Methods: In this retrospective cohort study, adult patients with ARDS (PaO₂/FiO₂ < 300 mmHg) who received mechanical ventilation in the ED were included. Ventilator parameters and clinical severity scores (SOFA, APACHE II, PSI, and Charlson Comorbidity Index) were recorded at the 120th minute after intubation. Patients were categorized as COVID-19 or non-COVID-19 ARDS, and outcomes were compared between survivors and non-survivors. Logistic regression was used to identify independent predictors of in-hospital mortality. Results: A total of 70 patients were enrolled (32 COVID-19, 38 non-COVID). Plateau pressure, driving pressure, and PEEP were significantly higher in COVID-19 patients, while compliance was without statistical significance. Overall, in-hospital mortality did not differ significantly between the COVID-19 (53.1%) and non-COVID-19 groups (71.1%, p = 0.12). Mechanical power (21.6 vs. 16.8 J/min, p = 0.01) and Charlson Comorbidity Index (6 vs. 5.5, p = 0.02) were significantly higher in non-survivors across the full cohort. Among clinical scores, SOFA was significantly higher in the COVID-19 group (p = 0.02), and APACHE II was significantly higher in non-survivors within the COVID-19 subgroup (p = 0.02). In multivariate analysis, mechanical power and Charlson Comorbidity Index were associated with mortality. Conclusions: COVID-19 patients with ARDS exhibited higher early ventilatory pressures than non-COVID-19 patients, yet early respiratory mechanics were not independently associated with mortality. Mechanical power and Charlson Comorbidity Index were significantly associated with in-hospital mortality. These findings underscore the need to consider both ventilatory load and systemic health status in early outcome assessments of ARDS patients. Full article

Background: Chronic heart failure (CHF) continues to present significant prognostic challenges despite advances in diagnosis and therapy. While the N-terminal prohormone of brain natriuretic peptide (NT-proBNP) is widely recognized as a key marker of cardiac stress, and serum albumin reflects systemic inflammation and nutritional status, their integration into a single parameter—the NT-proBNP-to-albumin ratio (NTAR)—may improve risk stratification. This study aimed to evaluate the NTAR as a novel biomarker for predicting in-hospital mortality in patients with CHF. Methods: We performed an exploratory, retrospective, observational, single-center study involving 542 patients (306 males) admitted for CHF between January 2022 and August 2024. NTAR was calculated as log₁₀(NT-proBNP/albumin). Statistical analyses included ROC curves, univariate and multivariable Cox regression, and Kaplan–Meier survival analysis. Sex-specific performance of NTAR was compared against NT-proBNP and serum albumin alone. Results: Females had significantly lower serum albumin levels than males, while NT-proBNP levels were similar across sexes. NTAR increased with NYHA functional class and was highest in patients with heart failure with reduced ejection fraction (HFrEF). NTAR showed very good discriminatory performance for predicting in-hospital mortality (AUC = 0.840, 95% CI: 0.794–0.879, p < 0.001), marginally but statistically outperforming NT-proBNP in the male subgroup. In univariate Cox regression analyses, higher serum albumin was significantly associated with reduced in-hospital mortality risk in males (HR = 0.352; 95% CI: 0.154–0.803; p = 0.010) and females (HR = 0.169; 95% CI: 0.072–0.399; p < 0.001). Elevated NT-proBNP levels were associated with increased mortality risk in males (HR = 8.627; 95% CI: 1.956–38.042; p < 0.001) and females (HR = 6.060; 95% CI: 1.498–24.521; p = 0.002) with similar findings in NTAR (HR_males = 10.318, 95% CI: 2.452–43.417, p < 0.001 and HR_females = 7.542, 95% CI: 1.874–30.358, p < 0.001). Multivariable analysis identified NTAR as the strongest independent predictor for in-hospital mortality among males. Conclusions: These findings suggest that NTAR effectively integrates cardiac and systemic dysfunction to improve mortality risk stratification in CHF, particularly in male patients. Its ease of calculation from routinely available biomarkers supports its clinical applicability. Full article

Background/Objectives: This study aimed to determine the in-hospital mortality rate after upper gastrointestinal (GI) bleeding in geriatric patients with comorbidities. Additionally, it sought to identify effective cut-off values for predicting high-risk patients using AIMS65 and Rockall scores and to assess the impact of oral anticoagulant and NSAID use on mortality. Methods: A retrospective cohort study was conducted on 64 patients aged 60 and above with at least one comorbidity who were admitted for upper GI bleeding between January 2023 and June 2024. AIMS65 and Rockall scores were calculated for each patient. The relationship between these scores, medication use, and mortality was analyzed using statistical methods, including ROC analysis and Kaplan–Meier survival curves. Results: The mean age was 77.6 years, and all patients had at least one chronic disease; 57.8% used medications increasing bleeding risk. In-hospital mortality was 18.7%, with no significant association for oral anticoagulants (p = 0.275) or NSAIDs (p = 0.324). Sepsis, heart failure, chronic renal failure, and malignancy were strongly linked to mortality in univariate analysis; multivariate analysis confirmed sepsis and malignancy as independent predictors, with a trend for heart failure. AIMS65 ≥ 2 (sensitivity 90.1%, AUC = 0.920) and Rockall ≥ 6 (sensitivity 91.7%, AUC = 0.822) were both effective in predicting mortality, with risk rising cumulatively with higher scores (p < 0.001). Conclusions: In-hospital mortality after upper GI bleeding is high in elderly patients with multiple comorbidities, mainly from sepsis, malignancy, and heart failure. AIMS65 and Rockall scores effectively predict mortality and may support earlier intervention. The small, high-risk cohort limits generalizability, underscoring the need for multicenter validation. Full article

Background and Objectives: Early identification of patients at risk of clinical deterioration is essential for optimizing therapeutic management and improving outcomes in general medicine wards. The National Early Warning Score 2 (NEWS2) is a validated tool for predicting patient worsening but integrating it with additional clinical and demographic data can enhance its predictive accuracy and support timely clinical decisions. Material and methods: In this retrospective cohort study, 2108 patients admitted to the general medicine department of the University Hospital of Siena were analyzed. Logistic regression models incorporating NEWS2 alongside key clinical variables—including age, presence of central venous catheter (CVC), and functional status measured by the Barthel Index—were developed to predict high clinical risk (HCR) and mortality. Model performance was assessed using the area under the ROC curve (AUC). Results: High clinical risk status developed in 29% of patients. Older age, presence of CVC, lower Barthel Index, and higher NEWS2 scores were significantly associated with both HCR and mortality. The integrated predictive model demonstrated good accuracy, with an AUC of 0.798 for HCR and 0.716 for mortality prediction. Conclusions: This study suggests that NEWS2, when combined with additional patient-specific variables from the electronic health record, can become a more sophisticated tool for early risk stratification. Such a tool has the potential to support timely clinical intervention and optimized therapeutic management, potentially contributing to improved patient outcomes. While the model may indirectly support nurse workload balancing by identifying patients requiring intensified care, its ultimate impact on patient outcomes requires confirmation through prospective studies. Full article

Background: The perfusion of viscera, kidney, and spinal cord represents one of the main concerns during open repair (OR) of Thoraco-Abdominal Aortic Aneurisms (TAAAs). Passive shunting (PS) has been historically used for intraoperative distal aortic perfusion but has been progressively replaced almost entirely by partial left-sided heart or total cardiopulmonary bypass with extra-corporeal circulation (ECC). Despite several advantages of these methods, PS still has potential in mitigating some drawbacks of long extracorporeal circuits connected with centrifugal or roller pumps, such as the need for cardiac and great vessels cannulation, priming and large intravascular fluid volume shifts, high heparin dose, immunosuppressive effects, and systemic inflammatory response syndrome. Methods: This study prospectively analyzed data of a cohort of patients who underwent TAAA OR using a PS in a single institution. Outcomes of interest were mortality, rate of mesenteric, renal and spinal cord ischemia, cardiac complications, and intraoperative hemodynamic stability achieved in this setting. Our institutional bundle and a comprehensive literature review about the different configurations and applicability of PS for TAAA OR is also reported. The search was performed based on three databases (PubMed, EMBASE, and Cochrane Library) by two independent reviewers (LS and AA) from inception to 31 December 2023, and the reported clinical results (visceral, renal, and spinal cord complications and mortality) using PS during TAAAs OR were analyzed. Results: Between March 2021 and December 2023, 51 TAAA repairs were performed and eleven patients (n = 8, 73% male; mean age 67 years, range 63–79) were operated using a PS for a total of one (9%) type I, one (9%) type II, two (18%) type III, five (45%) type IV, and two (18%) type V TAAA. In our early experience, PS was indicated for limited staff resources during the COVID-19 pandemic to treat five non-deferable cases. The sixth and seventh patients were selected for PS as they already had a functioning axillo-bifemoral bypass that was used for this purpose. For the most recent cases, PS was chosen as the primary perfusion method according to a score based on clinical and anatomical factors with ECC as a bailout strategy. Selective renal perfusion with cold (4 °C) Custodiol solution was the method of choice for renal protection in all cases while antegrade perfusion of the coeliac trunk and the superior mesenteric artery was assured by PS through a loop graft (8–10mm) proximally anastomosed to the axillary artery (10 patients, 90.9%) or the descending thoracic aorta (one patient, 9%) and distally anastomosed to the infrarenal aorta (3), common iliac (3), or femoral vessels (5). In-hospital mortality was 9% as one patient died on the 10th postoperative day from mesenteric ischemia following hemodynamic instability; permanent spinal cord ischemia rate was 0% and the rate of AKI stage 3 was 9% (one patient). Bailout shifting to ECC was never required. No cardiac complications, nor a significant increase in serum CK-MB were reported in any patient. No prolonged severe intraoperative hypotension episodes (Mean Arterial Pressure < 50 mmHg) were assessed using the Software Acumen Analytics (Edwards LifeSciences, Irvine CA, USA). No peri-operative coagulopathy nor major bleeding was reported. Conclusions: Our experience showed satisfactory outcomes with the use of PS in specifically selected cases. Current data indicate that PS may represent an alternative to ECC techniques during TAAAs OR in high volume centers where assisted extracorporeal circulation could eventually be applied as a bailout strategy. However, due to the small sample size of this and previously published series, more data are needed to clearly define the potential role of such approach during TAAA OR. Full article

(1) Background: COVID-19 sepsis, marked by hyperinflammation and cardiac injury, poses significant challenges in high-comorbidity populations. This prospective cohort study evaluates the prognostic value of IL-6, troponin, NT-proBNP, and radiological findings for mortality and unfavorable outcomes in a post-2022 Eastern European cohort. (2) Methods: At “Victor Babes” Hospital, Timisoara, Romania (September 2022–December 2024), 207 adults with COVID-19 sepsis (Sepsis-3 criteria) were enrolled. Baseline IL-6, troponin, NT-proBNP, CRP, PCT, D-dimers, and chest CT lung involvement were measured. Unfavorable outcomes (in-hospital death, ICU transfer, mechanical ventilation, or vasopressor use) were analyzed using logistic and linear regression. (3) Results: Among 207 patients (mean age: 68.7 years, 54.1% male), 52 (25.1%) experienced unfavorable outcomes. Multivariable analysis identified IL-6 (OR 1.016 per pg/mL, p = 0.013), troponin (OR 1.013 per ng/L, p = 0.017), NT-proBNP (OR 1.009 per pg/mL, p = 0.049), >50% lung involvement (OR 1.835, p = 0.011), unvaccinated status (OR 2.312, p = 0.002), and higher BMI (OR 1.112 per kg/m², p = 0.005) as independent predictors of unfavorable outcomes. Tocilizumab use (n = 12) was associated with reduced mortality (p = 0.041). IL-6 (cut-off 39.0 pg/mL, AUC = 0.91) and troponin (cut-off = 111.3 ng/L, AUC = 0.88) showed strong predictive accuracy. (4) Conclusions: Elevated IL-6, troponin, NT-proBNP, severe lung involvement, unvaccinated status, and higher BMI predict adverse outcomes in COVID-19 sepsis. Tocilizumab may offer survival benefits, warranting larger trials. These findings support targeted risk stratification in high-comorbidity populations. Full article

Tick-borne diseases (TBDs) are a growing public health concern in the United States. This study analyzed 261,630 weighted hospitalizations from the Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) database between 2002 and 2021 to evaluate trends, coinfections, demographic disparities, and financial impacts. Lyme disease was the most common cause, accounting for 65% of hospitalizations (171,328 admissions), followed by ehrlichiosis/anaplasmosis (46,446), babesiosis (18,057), rickettsial diseases (16,412), tularemia (2428), and other TBDs (19,435). Hospitalizations increased 2.5-fold over the study period, with the Northeast region bearing 52.9% of the burden and peaking in July. Males (53.9%), Caucasians (81.4%), and residents of higher-income zip codes were predominant, though rickettsial diseases showed elevated Hispanic representation (18.4%). Coinfections were common, with 35.8% of babesiosis and 15.6% of ehrlichiosis/anaplasmosis cases involving another TBD, suggesting that routine testing may be warranted. Median hospital charges rose from USD 9433 in 2002 to USD 35,161 in 2021, totaling USD 1.265 billion in 2021. In-hospital mortality was 1.1%, with the highest cause of mortality being babesiosis (2.06%). Future areas for research include characterizing the burden of disease in an outpatient setting, understanding the causes of racial disparities in hospitalizations, and testing strategies to identify coinfection. Full article

Background: Chronic obstructive pulmonary disease (COPD) is a prevalent condition with high morbidity and mortality, often accompanied by comorbidities such as alcohol use disorder (AUD). A thorough understanding of the interaction between COPD and AUD is crucial for improving patient outcomes and addressing management challenges. Objectives: This study analyzed temporal trends, clinical characteristics, and hospital outcomes associated with AUD among adults hospitalized with COPD in Spain between 2016 and 2023. Methods: A population-based cohort study was conducted using the Spanish Hospital Discharge Registry. We included adults aged ≥40 years with a diagnosis of COPD. AUD was identified through ICD-10 codes. Temporal trends in AUD prevalence were evaluated using Joinpoint regression, stratified by sex. We also assessed clinical characteristics including pneumonia, obesity, asthma, obstructive sleep apnea (OSA), supplemental oxygen use, long-term steroid use, and mechanical ventilation. Outcomes analyzed included ICU admission and in-hospital mortality (IHM). Results: Among 2,545,151 COPD hospitalizations, 263,568 (10.35%) had an AUD diagnosis. AUD prevalence rose from 8.66% in 2016 to 12.57% in 2023, with a sharper increase in women. Patients with AUD were younger and had higher rates of tobacco use (84.11% vs. 49.33%; p < 0.001) and psychiatric disorders. Multivariable analysis showed male sex, substance use, psychiatric illness, and external cause admissions were independently associated with AUD. Although overall IHM was lower in AUD patients (7.46% vs. 8.2%; p < 0.001), it increased with age, pneumonia, COVID-19, and higher comorbidity. IHM rose progressively, peaking in 2023 (15.6%). Conclusions: AUD prevalence in COPD hospitalizations increased significantly, especially in women. IHM also rose over time. These results highlight the need for integrated approaches targeting mental health and substance use in COPD management. Full article

Introduction: Sepsis, and particularly septic shock, is a life-threatening condition associated with high mortality rates in the emergency department. Timely interventions can significantly reduce these unacceptably high mortality rates. While some studies have demonstrated reduced mortality with early norepinephrine initiation, there is limited research on this intervention specifically within the emergency department setting. The objective of this study was to determine the association between the time to norepinephrine initiation in the emergency department and in-hospital mortality in adult patients diagnosed with septic shock. Methods: This retrospective cohort study included adult patients diagnosed with septic shock in the emergency department. Demographics, paraclinical variables, and the time to norepinephrine initiation were evaluated. In-hospital mortality was defined as the primary outcome. Finally, a multivariate analysis was performed to develop a nomogram for predicting septic shock mortality from the emergency department. Results: A total of 176 patients were included. A significant difference was documented between the time to norepinephrine initiation (in minutes) and survival rates: median (IQR) 12 (2–29) min for survivors versus 104 (68–181) min for non-survivors (p < 0.001). Similarly, when the time to initiation was divided into three groups (<60, 61–179, >179 min), a differential association with mortality was observed: OR 0.16 (95% CI; 0.08–0.32), OR 5.59 (95% CI; 2.67–11.6), and OR 353 (95% CI; 20.8–5978.9), respectively. Additionally, variables associated with mortality included mean arterial pressure, arterial lactate, and creatinine levels. Conclusions: Early initiation of norepinephrine in the emergency department may lower in-hospital mortality from septic shock without raising arrhythmia rates. Further high-quality studies are needed to confirm this and identify the patients who would benefit most. Full article

Background: Transcatheter aortic valve implantation (TAVI) is increasingly used in elderly patients with severe aortic stenosis, yet data on nonagenarians remain limited. This study aimed to compare clinical characteristics and outcomes of patients aged ≥90 years with those aged <90 years undergoing TAVI. Methods: We retrospectively analyzed 620 patients who underwent transfemoral TAVI. Patients were divided into two groups: <90 years (n = 545) and ≥90 years (n = 75). Baseline clinical, procedural, and outcome data were compared. Results: Nonagenarians had lower body mass index (BMI) and a lower prevalence of comorbidities such as diabetes, hyperlipidemia, and prior coronary artery bypass grafting CABG (all p < 0.05). All-cause mortality was higher in nonagenarians at 1 month (8.0% vs. 5.5%, p = 0.425), 6 months (9.3% vs. 7.9%, p = 0.838), and 1 year (21.3% vs. 16.7%, p = 0.405), though these differences were not statistically significant. In-hospital stroke occurred more frequently in patients ≥ 90 years (6.7% vs. 2.2%, p = 0.044). Conclusions: Despite a higher rate of in-hospital stroke, nonagenarians undergoing TAVI had comparable mortality outcomes to younger patients. These findings support the feasibility of TAVI in selected very elderly patients, while highlighting the need for tailored stroke prevention strategies. Trial Registration: The trial is retrospectively registered, and a clinical trial number is not applicable. Full article

Objectives: Personalized sepsis care requires understanding how pre-existing health status can influence outcomes. The aim of this study is to evaluate its impact on in-hospital and 12-month mortality in patients with sepsis, taking into account age, comorbidities, the Charlson Comorbidity Index, frailty, anemia, and the Sequential Organ Failure Score Assessment (SOFA) in the first 24 h. Methods: An observational and retrospective study was conducted using data from the Sepsis Code program at the Hospital Universitario de La Princesa. The relationship between risk factors and mortality, as well as Intensive Care Unit (ICU) admission, was analyzed for the period 2016–2018 using bivariate and multivariate logistic regression. Results: A total of 547 patients were included. In the multivariate analysis, the risk factors independently associated with mortality were Rockwood Clinical Frailty Scale ≥ 5 (OR 2.45, p < 0.05); SOFA ≥ 4 (OR 2.13, p < 0.05); age (OR 1.98, p < 0.05); anemia (OR 1.85, p < 0.05); and specific comorbidities such as ischemic heart disease (OR 2.34, p < 0.05), severe liver disease (OR 3.62, p < 0.05), and metastatic cancer (OR 3.14, p < 0.05). Patients who were frail, had dementia, or heart failure were less likely to be admitted to the ICU. Conclusions: Frailty, comorbidities, age, and anemia are associated with outcomes in patients with sepsis and could be incorporated into mortality prediction models to guide tailored treatment strategies. Full article

Background/Objectives: Prognostic biomarkers are essential for guiding the clinical management of pulmonary hypertension (PH). This study aimed to assess both established and novel biomarkers—specifically, the red cell distribution width-to-estimated glomerular filtration rate ratio (RGR) and the NT-proBNP-to-albumin ratio (NTAR)—for their ability to predict length of hospital stay (LOS), prolonged LOS (ELOS), in-hospital mortality, and 3-month all-cause mortality in patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). Methods: A retrospective analysis was conducted on 275 PH-related hospital regular admissions (148 PAH; 127 CTEPH). Established biomarkers—including serum albumin, neutrophil-to-lymphocyte ratio (NLR), Log NT-proBNP, red cell distribution width (RDW), and estimated glomerular filtration rate (eGFR)—as well as novel indices (RGR, and NTAR) were examined for their relationships with LOS, ELOS, in-hospital mortality, and 3-month all-cause mortality. Spearman correlation, univariate logistic regression, and ROC analyses evaluated biomarker relationships and predictive performance. Results: Serum albumin independently predicted in-hospital and 3-month mortality in PAH, while in CTEPH, it inversely correlated with LOS and strongly predicted prolonged hospitalization and mortality (AUC = 0.833). NLR had limited correlation with LOS but predicted mortality across both groups. RDW correlated weakly with LOS, significantly predicting prolonged hospitalization (threshold > 52.1 fL) in PAH but not in CTEPH. Preserved renal function (eGFR > 60 mL/min/1.73 m²) was inversely associated with LOS in CTEPH patients, suggesting a protective effect. Additionally, reduced eGFR significantly predicted mortality in both PAH (AUC = 0.701; optimal cut-off ≤ 97.4 mL/min/1.73 m²) and CTEPH (AUC = 0.793; optimal cut-off ≤ 59.2 mL/min/1.73 m²) groups. NTAR (AUC = 0.817) outperformed Log NT-proBNP alone in predicting extended hospitalization and mortality, whereas RGR correlated with LOS and predicted in-hospital mortality. Phenotype-specific analysis demonstrated that inflammatory and renal biomarkers had a stronger prognostic impact in CTEPH. Conclusions: Stratification by PH phenotype highlighted the greater prognostic significance of inflammatory and renal indices, particularly in patients with CTEPH. Incorporating NTAR and RGR into clinical workflows may enhance risk stratification and enable more precisely targeted interventions to improve outcomes in pulmonary hypertension. Full article

Myocardial infarction (MI) remains a leading cause of in-hospital mortality. Early identification of high-risk patients is essential for improving clinical outcomes and optimizing hospital resource allocation. This study presents a machine learning framework for predicting mortality following MI using a publicly available dataset of 1700 patient records, and after excluding records with over 20 missing values and features with more than 300 missing entries, the final dataset included 1547 patients and 113 variables, categorized as binary, categorical, integer, or continuous. Missing values were addressed using denoising autoencoders for continuous features and variational autoencoders for the remaining data. In contrast, feature selection was performed using Random Forest, and PowerTransformer scaling was applied, addressing class imbalance by using SMOTE. Twelve models were evaluated, including Focal-Loss Neural Networks, TabNet, XGBoost, LightGBM, CatBoost, Random Forest, SVM, Logistic Regression, and a voting ensemble. Performance was assessed using multiple metrics, with SVM achieving the highest F1 score (0.6905), ROC-AUC (0.8970), and MCC (0.6464), while Random Forest yielded perfect precision and specificity. To assess generalizability, a subpopulation external validation was conducted by training on male patients and testing on female patients. XGBoost and CatBoost reached the highest ROC-AUC (0.90), while Focal-Loss Neural Network achieved the best MCC (0.53). Overall, the proposed framework outperformed previous studies in key metrics and maintained better performance under demographic shift, supporting its potential for clinical decision-making in post-MI care. Full article

Background/Objectives: Community-acquired pneumonia (CAP) remains a major cause of hospitalisation and death, particularly among older and frail adults. Although treatment guidelines exist, adherence to empiric antibiotic recommendations is variable. This study examined whether receiving guideline-concordant antibiotics for CAP was associated with better short- and long-term clinical outcomes. Methods: We conducted a retrospective cohort study of adults admitted with radiologically confirmed CAP to a tertiary hospital in Australia from 1 January to 31 December 2023. Patients with hospital-acquired pneumonia or COVID-19 were excluded. Antibiotic concordance was assessed against local guidelines. Propensity score matching (PSM) accounted for 16 covariates including age, comorbidities (Charlson Index), frailty (Hospital Frailty Risk Score), and pneumonia severity (SMART-COP). Primary outcomes were in-hospital, 30-day, and one-year mortality. Secondary outcomes included ICU admission, invasive ventilation, vasopressor use, hospital length of stay, and 30-day readmissions. Results: Of 241 patients, 51.4% received guideline-concordant antibiotics. Mean age was 73.5 years; 50.2% were male; 42.2% had severe pneumonia (SMART-COP ≥ 5); 36.5% were frail. In unadjusted analysis, in-hospital mortality was higher in the concordant group (5.6% vs. 0.9%, p = 0.038). After PSM (n = 105 matched pairs), concordant treatment was associated with significantly lower 30-day mortality (coefficient = –0.12; 95% CI: –0.23 to –0.02; p = 0.018) and there was a non-significant trend towards reduced 1-year mortality (p = 0.058). Other outcomes, including in-hospital mortality, were not significantly different. Conclusions: Guideline-concordant antibiotics were associated with reduced 30-day mortality in CAP. These results support adherence to evidence-based treatment guidelines to improve patient outcomes. Full article

Background: High concentrations of supplemental oxygen (FiO₂ > 0.6) are commonly used to treat acute hypoxemia in critically ill patients. However, the effects of High FiO₂ in patients with COVID-19 remain unclear, particularly regarding its impact on hypoxic pulmonary vasoconstriction (HPV) and ventilation–perfusion (V/Q) mismatch. Objective: This study aims to evaluate whether administering lower concentrations of inspired oxygen (FiO₂ < 0.6) is associated with improved outcomes—namely reduced need for mechanical ventilation and mortality—in patients with COVID-19 and severe pulmonary involvement. Methods: This retrospective observational cohort included 201 patients with confirmed COVID-19. Patients were grouped by mean FiO₂ during the first 24–48 h: High FiO₂ (≥0.60) or Low FiO₂ (<0.60). The primary outcome was the requirement for mechanical ventilation; the secondary outcome was in-hospital mortality. A composite endpoint (mechanical ventilation and in-hospital death) was also evaluated. Analyses included logistic regression and Kaplan–Meier survival with log-rank testing. Results: High FiO₂ (≥0.60) was associated with higher odds of the composite outcome (mechanical ventilation and in-hospital death). In multivariable analysis, Low FiO₂ remained associated with lower odds (adjusted OR 0.18; 95% CI 0.08–0.39; p < 0.001). Unadjusted rates were 43.1% vs. 16.1% for mechanical ventilation and 34.3% vs. 8.1% for in-hospital death (High vs. Low FiO₂; both p < 0.001). Event-free survival favored the Low FiO₂ group (log-rank p < 0.001). The model showed excellent discrimination (AUC 0.96; 95% CI 0.92–0.99). Conclusions: Higher early FiO₂ exposure was associated with worse clinical outcomes in severe COVID-19. These findings are consistent with physiological models in which excess oxygen may attenuate hypoxic pulmonary vasoconstriction and increase shunt/dead space. Prospective studies are warranted to assess causality and refine oxygen targets. Full article