Background: There are insufficient data regarding how to deal with moderate aortic valve (AV) dysfunction during rheumatic mitral valve (MV) surgery. In this study, the clinical outcomes of patients who underwent rheumatic MV surgery with or without concurrent AV procedures were compared.

Methods: A total of 343 patients who underwent rheumatic MV surgery with moderate AV dysfunction were enrolled between January 2015 and August 2022, and a median 40-month follow-up was conducted. The more-than-mild AV dysfunction during follow-up was the primary endpoint event, while all-cause mortality and cardiac reoperation both before discharge and during follow-up encompassed the secondary endpoint events.

Results: Patients were allocated into two groups, including the no treatment (NT) (n=121) and aortic valvuloplasty (AVP) or aortic valve replacement (AVR) groups (n=222). Most of patients (110/121, 90.9%) in the NT group were combined with predominant aortic regurgitation. In the NT and AVP or AVR groups, 27.9% and 8.0% of patients reached the primary endpoint, and 5.0% and 7.3% of patients experienced the secondary endpoint events, respectively. This study confirmed a significantly higher proportion of patients in the NT group who reached the primary endpoint (relative risk, 2.98; 95% confidence interval: 1.61–5.62; P<0.001), after inverse probability treatment weighting.

Conclusions: Concomitant AV surgery significantly improved AV condition during follow-up for patients with moderate AV dysfunction during rheumatic valve surgery. However, it was safe and reasonable to delay surgical treatment of the AV and regular follow-ups for patients with predominant moderate aortic regurgitation.

Background: Tuberculosis infection (TBI) is a major challenge to global public health. Early detection and treatment of TBI are crucial in preventing tuberculosis (TB). Although inflammation is closely linked to the pathogenesis of TBI, the neutrophil-to-lymphocyte ratio (NLR), as a new inflammatory marker, has been less studied with TBI risk. This study was based on the National Health and Nutrition Examination Survey (NHANES) database. We utilized a cross-sectional research method to explore the association between NLR and the risk of adult TBI, aiming to fill the blank in the studying relationship between NLR and TBI risk. Our findings may contribute to providing new biomarkers for the diagnosis and treatment of TBI.

Methods: In this cross-sectional research, data from the NHANES database for the periods 1999–2000 and 2011–2012 were pooled for the study, with TBI as the dependent variable and NLR as the independent variable. A total of 2,433 participants were enrolled, including 391 TBI patients and 2,042 non-TBI patients. The inclusion criteria included information from complete blood testing and TBI status assessment. We evaluated demographic characteristics and clinical factors such as body mass index (BMI), smoking, drinking, NLR, and TBI risk. We employed weighted logistic regression to set up a relationship model between NLR and TBI and dissected the association between them through stratified analysis and subgroup analysis with confounding factors adjusted. We also utilized restricted cubic spline (RCS) and Kaplan-Meier (K-M) survival curves to investigate the nonlinear relationship between NLR and TBI, as well as their relationship with survival rates.

Results: A total of 2,433 samples were included in this project, with 391 TBI patients and 2,042 non-TBI patients. In the multivariable weighted logistic regression model, an obvious negative association was observed between NLR and TBI risk [odds ratio (OR) <1, P<0.05], and it was substantially influenced by diabetes (P for interaction =0.049). The negative association between NLR and TBI risk was particularly remarkable (P<0.05) in male and hypertensive patients. The RCS curve indicated a potential linear relationship between NLR and TBI risk (P-non-linear =0.9561), with NLR >1.899, OR <1, being a protective factor. The K-M survival curve revealed an obvious linkage between high NLR (>2.328) and increased death risk in TBI patients.

Conclusions: NLR is remarkably negatively linked with TBI risk. Patients with excessively high NLR have worse outcomes.

Keywords: Neutrophil-to-lymphocyte ratio (NLR); tuberculosis infection (TBI); hypertension; cross-sectional study; National Health and Nutrition Examination Survey (NHANES)

Background: Chronic obstructive pulmonary disease (COPD) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) pose global challenges, with oxygen saturation (SpO₂) levels crucial in evaluating mortality. This study explored the correlation between admission SpO₂ levels and all-cause hospital mortality in patients with AECOPD, assessing whether SpO₂ can serve as an independent risk factor for predicting in-hospital mortality in these patients.

Methods: This study involved 996 AECOPD patients sourced from the Medical Information Mart for Intensive Care (MIMIC) III database (version 1.3), with 134 fatalities. Patients were categorized into a death group (n=134) and a survival group (n=862). The average admission SpO₂ value was recorded for all 996 AECOPD patients. Subsequently, a generalized additive model (GAM) curve was employed to examine the association between admission SpO₂ levels and all-cause hospital mortality. Following this, Cox regression analysis and survival analysis were conducted to further investigate the link between admission SpO₂ and all-cause hospital mortality.

Results: The GAM curve demonstrated a non-linear, U-shaped relationship between admission SpO₂ and all-cause hospital mortality in AECOPD patients. The nadir of all-cause hospital mortality was associated with an SpO₂ of 89.5%. Notably, an SpO₂ of 89.5% served as the optimal cutoff for predicting all-cause hospital mortality. Cox regression analysis identified SpO₂ as a risk factor for all-cause hospital mortality in AECOPD patients. Patients with SpO₂ ≥89.5% exhibited independently lower death risk compared to those with SpO₂ <89.5% (hazard ratio: 0.52; 95% confidence interval: 0.37–0.74; P<0.001).

Conclusions: Admission SpO₂ level is an independent risk factor for predicting all-cause hospital mortality in AECOPD patients and can serve as a prognostic indicator. A U-shaped relationship was observed, with an admission SpO₂ level of 89.5% associated with the lowest mortality, suggesting an optimal range for improved prognosis.

Keywords: Chronic obstructive pulmonary disease (COPD); acute exacerbation stage; peripheral blood oxygen saturation (peripheral blood SpO₂); all-cause in-hospital mortality; Medical Information Mart for Intensive Care III database (MIMIC III database)

Background: Venovenous extracorporeal membrane oxygenation (VV-ECMO) is an effective lung protection strategy that avoids ventilator-induced lung injury. However, appropriate respiratory settings for VV-ECMO are yet to be established. This study aimed to elucidate the effects of ventilation under VV-ECMO using a newly developed rat VV-ECMO model and analyzed gene expression profiles.

Methods: Rats were assigned to three groups of five rats each: spontaneous breathing, conventional-protective ventilation, and ultra-protective ventilation. The conventional protective and ultraprotective ventilation groups received volume-controlled ventilation at a frequency of 60 and 20 beats/min, with tidal volumes of 6 and 3 mL/kg, respectively. VV-ECMO was performed at a pump flow rate of 20–30 mL/kg/min. At 120 min post initiation of VV-ECMO, rats were euthanized, and their lungs were harvested. Changes in gene expression were assessed using microarray analysis.

Results: Gene expression profile analyses revealed lowest expression of inflammation/immune promotion, cytotoxicity, and cell proliferation related genes (Defa5, Prg2, Siglec8, Atf3, Rnd1, Ctsg, and Gc), and the highest expression of inflammation/immune suppression related genes (Pp2d1) in the spontaneous breathing group as compared to that in the other two mechanical ventilation groups.

Conclusions: The findings of this study demonstrated that spontaneous breathing was the least invasive respiratory setting under VV-ECMO. Further, mechanical ventilation may be associated with lung injury even at low ventilation frequency and tidal volume.

Keywords: Gene expression; extracorporeal membrane oxygenation (ECMO); lung; ventilation; rat

Background: Unplanned early rehospitalization (UER) is common among lung transplant recipients, but its incidence varies among lung transplant centers. This study aimed to analyze the incidence, causes and predictors of UER in a lung transplant center in China and to explore the impact of preoperative nutritional risk status, postoperative duration of mechanical ventilation (MV) and extracorporeal membrane oxygenation support in the intensive care unit on unplanned readmission in lung transplant patients.

Methods: This study was conducted in one of the largest lung transplant centers in China. We collected demographic and clinical data from lung transplant recipients who underwent transplantation and were discharged in 2022. Predictors of UER within 30 days after discharge were analyzed through a retrospective cohort study.

Results: A total of 99 patients were included in this study. The incidence of UER was 29.3%. The three most common reasons were chest distress with shortness of breath (38%), cough with expectoration (21%), and fever (21%). Multivariate analysis revealed that the postoperative MV duration [odds ratio (OR) =1.027; 95% confidence interval (CI): 1.008–1.046; P=0.004] and preoperative Nutrition Risk Screening 2002 (NRS-2002) score (OR =1.615; 95% CI: 1.189–2.194; P=0.002) were significant risk factors for UER.

Conclusions: Patients with higher preoperative NRS-2002 scores and longer postoperative MV duration had a greater risk of UER within 30 days after initial discharge. More research is needed to determine whether improving preoperative nutritional risk status and shortening the duration of MV can reduce UER in patients.

Keywords: Lung transplantation; rehospitalization; unplanned early rehospitalization (UER)