Volume Categories Research Articles

The Impact of Hospital Delivery Volumes of Newborns Born Very Preterm on Mortality and Morbidity

To examine if the annual patient volume of infants born very preterm (VPT, gestational age <32weeks) at a hospital is associated with neonatal mortality and morbidity. We performed an observational, secondary data analysis using a 20-year panel of birth certificates linked to hospital discharge abstracts, including transfers in California, Michigan, Missouri, Oregon, Pennsylvania, and South Carolina from 1996 through 2015. The study included all in-hospital VPT deliveries (n=208 261). Study outcomes were in-hospital mortality or serious morbidity (intraventricular hemorrhage, necrotizing enterocolitis, retinopathy of prematurity, or bronchopulmonary dysplasia), attributed to the hospital of birth. Poisson regression models estimated the risk-adjusted relative risk (RR) for mortality and serious morbidity across different patient volume categories within a given hospital using hospital fixed effects. The risk of mortality and serious morbidity for VPT infants increased as the number of infants born VPT at a hospital decreased. Compared with VPT delivery volumes >100 infants per year, the risk of mortality increased when a given hospital had VPT delivery volumes < 60 per year, ranging from a RR of 1.13 (95% C.I. 1.02-1.25) for volumes between 50 to 59 and 1.39 (1.19-1.62) for VPT volumes <10, and the risk of mortality or serious morbidity increased when a given hospital had VPT volumes <100, ranging from a RR of 1.05 (1.02-1.08) for volumes between 90 to 99 and 1.27 (1.19-1.36) for VPT volumes <10. These results suggest that, for VPT infants, the risk of both mortality and mortality or serious morbidity is increased as the VPT volume within a given hospital declines.

Association of surgeon volume with complications following direct anterior approach (DAA) total hip arthroplasty: a population-based study.

Total hip arthroplasty (THA) can be performed through various surgical approaches, including direct anterior (DAA). DAA-THA may offer faster recovery but carries a higher risk of complications, which may be mitigated by surgeon volume and experience. We examined the association of surgeons' annual surgical volume with major complications after DAA-THA in a population-based sample. A population-based retrospective cohort study was carried out on primary DAA-THA patients in Ontario between April 2016 and March 2021. We used restricted cubic splines to visually define the association between annual DAA surgeon volume and the risk of major surgical complications (fractures, dislocations, infections, and revisions) within 1 year of surgery. We further compared the complication rates amongst different DAA volume categories (< 30, 30-60, and > 60 cases/year). The study encompassed 9,672 DAA-THA patients (52% female, median age 67 years). We showed a sharp decline in the probability of complications as the surgical volume of DAA-THA increased within the lower range of 0-30 cases/year; the probability slightly increased after the surgical volume exceeded 60 cases/year. The overall complication rates were 3.09%, 2.24%, and 2.18% for the surgical experience group of < 30 cases/year, 30-60 cases/year, and > 60 cases/year, respectively. There was an inverse relationship between surgical volume and complication rates in DAA-THA within the lower volume ranges. Maintaining a surgical volume of at least 30 DAA-THA cases/year can minimize complications, emphasizing the importance of surgical volume in this approach.

Ranking factors affecting the decontamination efficacy of non-thermal plasma: The approach of dissipated power per plasma volume through machine learning modeling

Non-thermal plasma treatment can preserve food, but a meta-analysis assessing its efficacy has not been performed. This study retrieved the inactivation kinetics parameter log10D (n = 519), which varied largely among different plasma setups. Atmospheric pressure plasma jet, corona discharge, surface barrier discharge, dielectric barrier discharge, and inductively-coupled plasma had the highest efficacy with median D-values under 2 min. Dielectric barrier discharge, the most frequent setup (n = 160), was analyzed using dissipated power per plasma volume (W/cm3) as an integrated predictor of decontamination efficacy. Using conventional and machine learning approaches the most correlated parameters to the log10D were: dissipated power per plasma volume and matrix category, followed by microbial genus and pH. This study uses active learning to improve literature screening for data collection and various data analysis techniques for data treatment and ranking of the factors affecting non-thermal plasma decontamination. Industrial relevanceNon-thermal plasma decontamination shows potential but is also highly affected by the setup, and technical, biological, and food parameters. This study gives an overview of the decontamination performance that is to be expected for different matrix categories and setups, which could guide possible industrial applications. The ranking of the most important parameters to affect decontamination efficacy could be used for the optimization of these applications.

Analysis of reconstitution process, stability, stability of intravenous antibiotics in hospitalised patients in a private hospital

Introduction: reconstitution of sterile preparations is a series of changes in the drug from its original condition to a new product by dissolving or adding other ingredients carried out aseptically by the pharmacy. Aim: determine the suitability of the reconstitution technique, the suitability of stability (solvent type and solvent volume), and the suitability of the sterility of the reconstitution product. Methods: data collection obtained by observation is carried out with the help of a checklist that is adapted to hospital standard operating procedures (SOPs), Inject-able Drug Guide, guidelines for mixing inject-able drugs, and preparations. 48 processes of reconstitution of intravenous antibiotics were carried out in hospitals that could be observed as samples. Results: conformity to the preparation stage were 99%, the mixing stage was 73%, the labelling was 100%, and the labelling was 90%. In evaluating the stability of the solvent type category, the suitability of 100%. In the volume category of the solvent used, 90% were suitable, and 10% were unsuitable for the antibiotic’s cefotaxime 1 gram, vancomycin 1 gram, and sulbactam + ampicillin Na 1 gram. From the sterility test results, the reconstitution of ceftriaxone intravenous antibiotic preparations showed that the bacterial preparations were free of microorganisms (sterile). Conclusion: the personnel performing the reconstitution are nurses trained in intravenous antibiotic recovery. One of the factors that caused the reconstitution process not to be under the hospital's KSB was the lack of training and supervision from the hospital management. SPO recovery is not installed in an intravenous drug mixing room.

Heart Transplantation After Donation After Circulatory Death: Early United States Experience

BackgroundGiven the renewed interest in heart transplantation after donation after circulatory death (DCD), a contemporary analysis of trends and longer-term survival is warranted. MethodsAdult heart transplant recipients (December 2019-September 2023) were identified in the Organ Procurement and Transplantation Network. Recipients were stratified as donation after brain death (DBD) or DCD. DCD procurements were further classified as direct procurement and perfusion (DCD-DPP) or normothermic regional perfusion (DCD-NRP), based on the declaration of death to cross-clamp interval (≥40 minutes DCD-NRP). The main outcome was posttransplant survival at 1 and 3 years. ResultsOf 11,625 transplantations, 792 (7%) involved DCD allografts (249 DCD-NRP, 543 DCD-DPP). The proportion of transplants involving DCD allografts significantly increased from 2% (December 2019) to 11% (January-September 2023, P < .001). Upon adjusted analysis, 1-year posttransplant survival was similar for DBD vs DCD-DPP (hazard ratio [HR], 1.00; 95% CI, 0.66-1.66) or DCD-NRP (HR, 0.92; 95% CI, 0.49-1.72). This remained true at 3 years for DCD-DPP (HR, 1.07; 95% CI, 0.77-1.48) and DCD-NRP (HR, 1.04; 95% CI, 0.62-1.73). Incidence of postoperative stroke, dialysis, acute graft rejection, and primary graft dysfunction were similar across groups. Across various strata of recipient risk and center volume, survival was equivalent between the DBD and DCD cohorts. ConclusionsRates of DCD heart transplantation continue to rise. Across various recipient risk and center volume categories, DCD and DBD recipients show comparable posttransplant survival up to 3 years. These findings encourage broader use of such donors in attempts to expand the organ pool.

H-mrk-means: Enhanced Heuristic mrk-means for Linear Time Clustering of Big Data Using Hybrid Meta-heuristic Algorithm

Big data is generally derived with a large volume and combined categories of attributes like categorical and numerical. Among them, [Formula: see text]-prototypes have been adopted into MapReduce structure, and thus, it provides a better solution for the huge range of data. However, [Formula: see text]-prototypes need to compute all distances among every data point and cluster centres. Moreover, the computations of distances are redundant as data points are often present in similar clusters after fewer iterations. Nowadays, to cluster huge-scale datasets, one of the efficient solutions is [Formula: see text]-means. However, [Formula: see text]-means is not intrinsically appropriate to execute in MapReduce due to the iterative nature of this technique. Moreover, for every iteration, [Formula: see text]-means should perform an independent MapReduce job but, it leads to higher Input/Output (I/O) overhead at every iteration. This research paper presents a novel enhanced linear time clustering for handling big data called Heuristic mrk-means (H-mrk-means) using optimized [Formula: see text]-means on the MapReduce model. In order to manage big data that is time series in nature, the sampling and MapReduce framework are adopted, which utilize different machines for processing data. Before initiating the main clustering process, a sampling process is adopted to get the noteworthy information. The two main phases of the developed method are the map phase (divide and conquer) and the reduce phase (final clustering). In the map phase, the data are divided into diverse chunks that should be stored in assigned machines. In the reduce phase, data clustering is performed. Here, the cluster centroid of data is tuned with the help of hybrid Tunicate-Deer Hunting Optimization (T-DHO) algorithm by attaining a newly derived objective function. This type of optimal tuning of solution enhances the efficiency of clustering when compared over normal iterative [Formula: see text]-means and mrk-means clustering. The experimental evaluation on varied counts of chunks using the proposed H-mrk-means has attained higher quality of clustering results and faster execution times evaluated with other clustering approaches.

Using the Stratum-Specific Likelihood Ratio Method to Derive Outcome-Based Hospital Volume Categories for Total Knee Replacement.

Evidence of higher hospital volume being associated with improved outcomes for patients undergoing total knee replacement (TKR) is mostly based on arbitrary distribution-based thresholds. We aimed to define outcome-based volume thresholds using data from a national database. We used the MedPAR Limited Data Set inpatient data from 2010-2015 to identify patients who had undergone primary TKR. Surgical and TKR specific complications occurring within the index hospitalization and all-cause readmission within 90 days were considered adverse events. We derived an average annual TKR case volume for each hospital and applied the stratum-specific likelihood ratio method to determine volume categories indicative of a similar likelihood of 90-day post-operative complications. Hierarchical multivariable logistic regression with a random intercept for hospital nested within study year and adjusted for patient and hospital characteristics was performed to determine if these volume thresholds were still associated with the odds of 90-day readmission for complications after adjustment. SSLR analysis yielded 4 hospital volume categories based on the likelihood of 90-day postoperative complications: 1-31 (low), 32-127 (medium), 128-248 (high), and 429+ (very high) TKRs performed per year. The results of the hierarchical multivariable logistic regression showed significantly increased odds of 90-day complications at lower volume categories. Sensitivity analyses confirmed our main findings. This study is the first to provide national-level volume categories that are evidence-based. Publicizing these thresholds may enhance quality measures available to patients, providers, and payors.

The Role of Digital Rectal Examination Prostate Volume Category in the Early Detection of Prostate Cancer: Its Correlation with the Magnetic Resonance Imaging Prostate Volume.

To relate the prostate volume category (PVC) assessed with digital rectal examination (DRE)-small, median, and large-and the prostate volumes (PVs) assessed with magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS). To compare the clinically significant prostate cancer (csPCa) discrimination ability of two predictive models based on DRE-PVC and MRI-PV. A prospective trial of 2,090 men with prostate-specific antigen >3 ng/mL and/or PCa suspicious DRE were prospectively recruited in 10 centers from Catalonia (Spain), between 2021 and 2022, in whom DRE-PVC was assessed. Pre-biopsy MRI, and 12-core TRUS-random biopsy was always performed after 2- to 6-core TRUS-fusion targeted biopsy of prostate imaging-report and data system >3 lesions. In 370 men (17.7%) the DRE-PVC was unconclusive. Among the 1,720 men finally analyzed the csPCa (grade group >2) detection was 42.4%. The median (interquartile range) of TRUS and MRI-PVs of small prostates were 33 mL (19-37 mL) and 35 mL (23-30 mL), p=0.410; in median prostates they were 51 mL (38-58 mL) and 55 mL (48-63 mL) respectively, p<0.001; in large prostates 80 mL (60-100 mL) and 95 mL (75-118 mL) respectively, p<0.001. The predictive models sharing the MRI-PV and DRE-PVC showed areas under the curves of 0.832 (95% confidence interval [CI], 0.813-0.851) and 0.828 (95% CI, 0.809-0.848) respectively, p=0.632, as well as similar net benefit and clinical utility. PVC was unconclusive in 17% of DREs. MRI-PV overestimated the TRUS-PV in median and large prostates. The predictive models based on MRI-PV and DRE-PVC showed similar efficacy to predict csPCa. PVC assessed with DRE is helpful to predict the csPCa risk before MRI.

DETERMINATION OF THE RELATIONSHIP BETWEEN VOLUME AND DIFFUSION AREAS OF HAZARDOUS MATERIALS ON POROUS MEDIA

One of the focused areas that transportation industry has to overcome is safe transportation of hazardous materials (HAZMATs). The low probability/high consequence nature of the HAZMAT transportation necessitates assessing the risk associated with HAZMAT transportation. To fully understand the potential consequences of HAZMAT accidents, estimating the diffusion area under different spill volumes for various HAZMATs is needed for a complete risk assessment. The main purpose of this study is to develop a relationship between the volume and the diffusion area for six analytes: 75&amp;#37; methanol, 70&amp;#37; ethanol, 36&amp;#37; HCL, 40&amp;#37; NaOH, Bakken, and Niobrara crude oils. We evaluate the distribution of the diffusion area with respect to 11 volume categories at five temperatures. This study also utilizes a circular chromatography approach to identify the diffusion area with respect to 11 volume levels. The findings of the study show that analytes diffusion can be explicitly explained by linear regression, polynomial regression, and power regression. Methanol at 0&amp;#176;C to 30&amp;#176;C, ethanol at 10&amp;#176;C and 20&amp;#176;C, HCL at 20&amp;#176;C, and NaOH at 10&amp;#176;C can be explained by linear regression, while methanol at 40&amp;#176;C can be explained by power regression. All other analytes followed polynomial regression trends. One notable finding is that NaOH, Bakken, and Niobrara crude oils' diffusion times decrease with temperature increase.

Influence of Procedural Volume on the Outcome of Gastric Endoscopic Submucosal Dissection: A Nationwide Population-Based Study Using Administrative Data

Background & AimsEndoscopic submucosal dissection (ESD) is a well-established treatment modality for gastric neoplasms. We aimed to investigate the effect of procedural volume on the outcome of ESD for gastric cancer or adenoma. MethodsIn this population-based cohort study, patients who underwent ESD for gastric cancer or adenoma from November 2011 to December 2017 were identified using the Korean National Health Insurance Service database. Operational definitions to identify the target population and post-procedural complications were created using diagnosis and procedure codes and were validated using hospital medical record data. Outcomes included hemorrhage, perforation, pneumonia, 30-day mortality, a composite outcome comprising all these adverse outcomes, and additional resection. Hospital volume was categorized into three groups based on the results of the threshold analysis: high-, medium-, low-volume centers (HVCs, MVCs, and LVCs, respectively). Inverse probability of treatment (IPT) weighting analysis was applied to enhance comparability across the volume groups. ResultsThere were 94,246 procedures performed in 88,687 patients during the study period. There were 5,886 composite events including 4,925 hemorrhage, 447 perforation, and 703 pneumonia cases. There were significant differences in ESD-related adverse outcomes among the three hospital volume categories, showing that HVCs and MVCs were associated with a lower risk of a composite outcome than LVCs (IPT-weighted odds ratio (OR), 0.651, 95% confidence interval (CI), 0.521–0.814; IPT-weighted OR, 0.641, 95% CI, 0.534–0.769). Similar tendencies were also shown for hemorrhage, perforation, and pneumonia; however, these were not evident for additional resection. ConclusionProcedural volume was closely associated with clinical outcome in patients undergoing ESD for gastric cancer or adenoma.

Temporal trends, patient characteristics and hospital volume outcomes after alcohol septal ablation and septal myectomy for treatment of obstructive hypertrophic cardiomyopathy

Abstract Background Hypertrophic obstructive cardiomyopathy (HOCM) represents a clinically and morphologically diverse hereditary cardiac disease that is frequently associated with poor prognosis. Nationwide data on septal reduction therapy (SRT), alcohol septal ablation (ASA) and septal myectomy (SM), remains scarce. The aim of this study was to investigate (i) temporal trends, (ii) patient characteristics, (iii) in-hospital outcomes, and associations between institutional procedural volumes and outcomes after ASA and SM in a large-scale nationwide cohort. Methods Using data from the German Federal Bureau of Statistics, this study analyzed all patients with HOCM who were hospitalized for ASA or SM in a nationwide inpatient database in Germany between January 1, 2006, through December 31, 2019. Rates of adverse in-hospital events (in-hospital mortality, need for permanent pacemaker) were examined. Multivariate logistic regression analysis was performed to compare overall outcomes after each procedure based on tertiles of hospital volumes of ASA and SM. Results A total of 8,514 patients underwent SRT, of whom 5,293 (62.2%) underwent ASA and 3,221 (37.8%) SM. Annual numbers for SM and ASA steadily increased over time: ASA procedures increased from 329 in 2006 to 451 in 2019 and SM procedures increased from 191 in 2006 to 222 in 2019, respectively. Patients with SM were older (mean 67.4 vs. 60.2 years), less likely female (56.4% vs. 49.9%), and had a higher burden of comorbidities (e.g., diabetes, atrial fibrillation, heart failure, chronic kidney disease) compared to patients with ASA. Over an observational period of 14 years, the majority of both ASA and SM procedures were performed at hospitals in the lowest volume category (≤20 procedures). The overall in-hospital mortality was higher in patients with SM (6.8%) compared to patients with ASA (0.8%), whereas the need for pacemaker implantation was more often observed in patients with ASA (19.3% vs. 13.1%; p&amp;lt;0.001). The lowest tertile of SM volume among hospitals was independently associated with an increased risk of in-hospital mortality (adjusted odds ratio (lowest vs. highest tertile), 2.64; 95% confidence interval, 1.49-4.66), whereas being in the lowest vs. the highest tertile of ASA by volume was not independently associated with risk of in-hospital mortality and adverse events. Conclusion In this contemporary cohort with more than 8,500 cases of SRT between 2006 and 2019, the majority of SRT was performed at centers with a low volume of SM and ASA procedures. Low SM volume was independently associated with increased in-hospital mortality, whereas low ASA volume was not associated with adverse outcomes. Our findings may help to further understand how institutional SRT procedural volumes affects outcomes and might encourage referral of patients with HOCM to centers of excellence for SRT.

Does Centralization of Radical Prostatectomy Reduce the Incidence of Postoperative Urinary Incontinence?

BackgroundOn the basis of previous analyses of the incidence of urinary incontinence (UI) after radical prostatectomy (RP), the hospital RP volume threshold in the Netherlands was gradually increased from 20 per year in 2017, to 50 in 2018 and 100 from 2019 onwards. ObjectiveTo evaluate the impact of hospital RP volumes on the incidence and risk of UI after RP (RP-UI). Design, setting, and participantsPatients who underwent RP during 2016–2020 were identified in the claims database of the largest health insurance company in the Netherlands. Incontinence was defined as an insurance claim for ≥1 pads/d. Outcome measurements and statistical analysisThe relationship between hospital RP volume (HV) and RP-UI was assessed via multivariable analysis adjusted for age, comorbidity, postoperative radiotherapy, and lymph node dissection. Results and limitationsRP-UI incidence nationwide and by RP volume category did not decrease significantly during the study period, and 5-yr RP-UI rates varied greatly among hospitals (19–85%). However, low-volume hospitals (≤120 RPs/yr) had a higher percentage of patients with RP-UI and higher variation in comparison to high-volume hospitals (>120 RPs/yr). In comparison to hospitals with low RP volumes throughout the study period, the risk of RP-UI was 29% lower in hospitals shifting from the low-volume to the high-volume category (>120 RPs/yr) and 52% lower in hospitals with a high RP volume throughout the study period (>120 RPs/yr for 5 yr). ConclusionsA focus on increasing hospital RP volumes alone does not seem to be sufficient to reduce the incidence of RP-UI, at least in the short term. Measurement of outcomes, preferably per surgeon, and the introduction of quality assurance programs are recommended. Patient summaryIn the Netherlands, centralization of surgery to remove the prostate (RP) because of cancer has not yet improved the occurrence of urinary incontinence (UI) after surgery. Hospitals performing more than 120 RP operations per year had better UI outcomes. However, there was a big difference in UI outcomes between hospitals.

Association Between Smoking and Hypertension in Pregnancy Among Japanese Women: A Meta-analysis of Birth Cohort Studies in the Japan Birth Cohort Consortium (JBiCC) and JECS.

Recent literature suggest the effect of maternal smoking on risk of hypertensive disorders in pregnancy (HDP) and preeclampsia may differ by ethnicity; however, studies on Asians are limited. We investigated the association of maternal smoking with HDP and preeclampsia using a common analysis protocol to analyze the association in six birth cohorts participating in a Japanese consortium of birth cohorts (JBiCC). Results were compared with-published results from cohorts not included in this consortium, and, where possible, we produced a meta-analysis including these studies. Meta-analysis of four cohort studies including 28,219 participants produced an odds ratio (OR) of 1.24 (95% confidence interval [CI], 0.88-1.87) for the effect of smoking beyond early pregnancy compared to women who did not smoke during pregnancy. These results combined with those from the Japan Environment and Children's Study (JECS) yielded an OR of 1.19 (95% CI, 1.00-1.43, P = 0.056). Meta-analysis results for categories of smoking volume were insignificant, but when combined with JECS yielded an OR of 0.86 (95% CI, 0.65-1.12) for smoking 1-4 cigarettes, 1.25 (95% CI, 0.98-1.60) for smoking 5-9 cigarettes, and 1.27 (95% CI, 1.04-1.54) for smoking 10 or more cigarettes per day. All effects were insignificant for preeclampsia. Our results suggest that the protective effects of smoking longer and smoking more on HDP and preeclampsia repeatedly observed among Europeans and North Americans likely do not hold for the Japanese.

Disparities in Initial Thyroid Cancer Care by Hospital Treatment Volume: Analysis of 52,599 Cases in California.

Background: Racially minoritized patients with thyroid cancer are less likely to receive high-quality and guideline-concordant care. Inaccessibility of high-volume centers may contribute to inequalities in thyroid cancer outcomes. This study sought to understand the extent to which access to higher volume thyroid cancer centers is associated with patient outcomes. Methods: We queried linked California Cancer Registry and California Office of Statewide Health Planning and Development databases for thyroid cancer patients who received thyroid surgery between 1999 and 2017. Hospitals were stratified by their median annual volume of thyroid cancer operations: ultra-low volume (0-5 cases/year), low-volume (6-25 cases/year), mid-volume (26-50 cases/year), and high-volume (>50 cases/year). We analyzed the rates of complications, rates of reoperation for cancer recurrence, use of radioactive iodine (131I), and mortality by median hospital volume of thyroid surgery. A multivariable regression controlled for high-risk tumor features. Differences in access by center volume were assessed based on patient demographics. Results: We studied 52,599 thyroid cancer patients who underwent thyroidectomy. Patients who underwent thyroidectomy at ultra-low volume centers were more likely to undergo reoperations for recurrent/persistent disease compared with patients at low- (odds ratio [OR] 1.17 [CI 1.02-1.35]), mid- (OR 1.25 [CI 1.06-1.46]), and high-volume centers (OR 1.26 [CI 1.03-1.56]). Patients who received thyroid operations at ultra-low volume centers were also less likely to receive guideline-concordant 131I ablation compared with patients at higher volume centers (OR 0.77 [CI 0.72-0.82]). A pair-wise comparison between all volume categories for all outcomes revealed no statistically significant differences in outcomes between low-, mid-, or high-volume centers. Only ultra-low volume centers had significantly higher rates of adverse outcomes. Ultra-low volume centers were disproportionately accessed by women (p < 0.05), Hispanic, Asian/Pacific Islander, and American Indian people (p < 0.01), those from the lowest three quintiles of socio-economic status (p < 0.01), and the uninsured and those on Medicaid or Medicare (p < 0.01) when compared with higher volume centers. Conclusions: Patients receiving thyroid cancer surgery at centers performing ≤5 such operations per year were more likely to require reoperation for recurrent/persistent disease and less likely to receive appropriate 131I ablation. Ultra-low volume centers served higher proportions of socially and economically marginalized communities.

Serial blood volume measurements in patients with compensated chronic heart failure: How do volume profiles change over time?

Among patients with chronic heart failure (HF) intravascular volume profiles vary significantly despite similar clinical compensation. However, little is known regarding changes in blood volume (BV) profiles over time. The objective of this analysis was to identify the extent and character of changes in volume profiles over time. A prospective analysis was undertaken in patients who were hospitalized and treated for fluid overload. Quantitative BV analyses were obtained in a compensated state at hospital discharge (baseline) and follow-up at 1, 3, and 6 mo. Data were available on 10 patients who remained stable without rehospitalization or medication change over a 6-mo period. Baseline BV profiles were highly variable at hospital discharge with an average deviation of +28% above normal in 6 patients and normal BV in 4 patients. Over the follow-up period, the median change in BV was -201 mL [-3% (-6, +3%)] from baseline with profiles remaining in the same volume category in 9 out of 10 patients. Crossover from normal BV to mild contraction (-13% of normal) occurred in one patient. Red blood cell mass demonstrated the largest change over 6 mo [median -275 (-410, +175) mL] with a deviation from normal of -14 (-20, +8) % (reflecting mild anemia). These findings suggest that BV profiles in clinically compensated patients with HF do not change substantially over a 6-mo period regardless of baseline expanded or normal BV. This lack of change in volume profiles particularly from an expanded BV has implications for long-term volume management, clinical outcomes, and also our understanding of volume homeostasis in HF.NEW & NOTEWORTHY The novel findings of this study demonstrate that blood volume profiles while highly variable in clinically compensated patients with HF on stable medical therapy do not change substantially over a 6-mo period regardless of baseline expanded or normal blood volumes. This lack of change in volume profiles particularly from an expanded blood volume has implications for long-term volume management and also for how we understand the pathophysiology of volume homeostasis in chronic HF.

Integrative Chemical-Biological Grouping of Complex High Production Volume Substances from Lower Olefin Manufacturing Streams.

Human cell-based test methods can be used to evaluate potential hazards of mixtures and products of petroleum refining ("unknown or variable composition, complex reaction products, or biological materials" substances, UVCBs). Analyses of bioactivity and detailed chemical characterization of petroleum UVCBs were used separately for grouping these substances; a combination of the approaches has not been undertaken. Therefore, we used a case example of representative high production volume categories of petroleum UVCBs, 25 lower olefin substances from low benzene naphtha and resin oils categories, to determine whether existing manufacturing-based category grouping can be supported. We collected two types of data: nontarget ion mobility spectrometry-mass spectrometry of both neat substances and their organic extracts and in vitro bioactivity of the organic extracts in five human cell types: umbilical vein endothelial cells and induced pluripotent stem cell-derived hepatocytes, endothelial cells, neurons, and cardiomyocytes. We found that while similarity in composition and bioactivity can be observed for some substances, existing categories are largely heterogeneous. Strong relationships between composition and bioactivity were observed, and individual constituents that determine these associations were identified. Overall, this study showed a promising approach that combines chemical composition and bioactivity data to better characterize the variability within manufacturing categories of petroleum UVCBs.

Obstetric Volume and Severe Maternal Morbidity Among Low-Risk and Higher-Risk Patients Giving Birth at Rural and Urban US Hospitals

ImportanceIdentifying hospital factors associated with severe maternal morbidity (SMM) is essential to clinical and policy efforts.ObjectiveTo assess associations between obstetric volume and SMM in rural and urban hospitals and examine whether these associations differ for low-risk and higher-risk patients.Design, Setting, and ParticipantsThis retrospective cross-sectional study of linked vital statistics and patient discharge data was conducted from 2022 to 2023. Live births and stillbirths (≥20 weeks’ gestation) at hospitals in California (2004-2018), Michigan (2004-2020), Pennsylvania (2004-2014), and South Carolina (2004-2020) were included. Data were analyzed from December 2022 to May 2023.ExposuresAnnual birth volume categories (low, medium, medium-high, and high) for hospitals in urban (10-500, 501-1000, 1001-2000, and &amp;amp;gt;2000) and rural (10-110, 111-240, 241-460, and &amp;amp;gt;460) counties.Main Outcome and MeasuresThe main outcome was SMM (excluding blood transfusion); covariates included age, payer status, educational attainment, race and ethnicity, and obstetric comorbidities. Analyses were stratified for low-risk and higher-risk obstetric patients based on presence of at least 1 clinical comorbidity.ResultsAmong more than 11 million urban births and 519 953 rural births, rates of SMM ranged from 0.73% to 0.50% across urban hospital volume categories (high to low) and from 0.47% to 0.70% across rural hospital volume categories (high to low). Risk of SMM was elevated for patients who gave birth at rural hospitals with annual birth volume of 10 to 110 (adjusted risk ratio [ARR], 1.65; 95% CI, 1.14-2.39), 111 to 240 (ARR, 1.37; 95% CI, 1.10-1.70), and 241 to 460 (ARR, 1.26; 95% CI, 1.05-1.51), compared with rural hospitals with greater than 460 births. Increased risk of SMM occurred for low-risk and higher-risk obstetric patients who delivered at rural hospitals with lower birth volumes, with low-risk rural patients having notable discrepancies in SMM risk between low (ARR, 2.32; 95% CI, 1.32-4.07), medium (ARR, 1.66; 95% CI, 1.20-2.28), and medium-high (ARR, 1.68; 95% CI, 1.29-2.18) volume hospitals compared with high volume (&amp;amp;gt;460 births) rural hospitals. Among hospitals in urban counties, there was no significant association between birth volume and SMM for low-risk or higher-risk obstetric patients.Conclusions and RelevanceIn this cross-sectional study of births in US rural and urban counties, risk of SMM was elevated for low-risk and higher-risk obstetric patients who gave birth in lower-volume hospitals in rural counties, compared with similar patients who gave birth at rural hospitals with greater than 460 annual births. These findings imply a need for tailored quality improvement strategies for lower volume hospitals in rural communities.

Black Patients are More Likely to Undergo Early Revision Total Knee Arthroplasty in a Matched Cohort Regardless of Surgeon Experience

BackgroundBlack patients are at an increased risk of aseptic revision total knee arthroplasty (TKA) when compared to White patients. The goal of this study was to determine whether racial disparities in revision TKA risk are related to surgeon characteristics. MethodsThis was an observational cohort study. We used inpatient administrative data to identify Black patients who underwent unilateral primary TKA in New York State. There were 21,948 Black patients who were matched 1:1 to White patients on age, sex, ethnicity, and insurance type. The primary outcome was aseptic revision TKA within 2 years of primary TKA. We calculated annual surgeon TKA volume and identified surgeon characteristics such as training in North America, board certification, and years of experience. ResultsBlack patients had a higher odds of aseptic revision TKA (odds ratio (OR) 1.32, 95% CI 1.12–1.54, P < .001) and were disproportionately cared for by low volume surgeons (≤12 TKA/year). The relationship between low volume surgeons and risk of aseptic revision was not statistically significant (OR 1.24, 95% CI 0.72-2.11, P = .436). The adjusted odds ratio (aOR) for aseptic revision TKA in Black versus White patients varied across surgeon/hospital TKA volume category pairs, with the greatest aOR when TKA were performed by the highest volume surgeons at the highest volume hospitals (aOR 2.8, 95% CI 0.98– 8.09, P = .055). ConclusionBlack patients were more likely to undergo aseptic TKA revision than matched White patients. This disparity was not explained by surgeon characteristics.

No Association Between Hospital Volume and Early Second Revision Rate in Revision Total Knee Arthroplasty in the Dutch Orthopaedic Register

BackgroundRevision knee arthroplasty (R-KA) is rising globally. Technical difficulty of R-KA varies from liner exchange to full revision. Centralization has been shown to reduce mortality and morbidity rates. The present study aimed to evaluate the association between hospital R-KA volume and overall second revision rate, as well as revision rate for different types of revision. MethodsThe R -KAs between 2010 and 2020 with available data on the primary KA in the Dutch Orthopaedic Arthroplasty Register were included. Minor revisions were excluded. Implant data and anonymous patient characteristics were obtained from the Dutch Orthopaedic Arthroplasty Register. Survival analyses and competing risk analysis were performed per volume category (≤12, 13 to 24, or ≥25 cases/year) at 1, 3, and 5 years following R-KA. There were 8,072 R-KA cases available. Median follow-up was 3.7 years (range 0 to 13.7 years). There were a total of 1,460 second revisions (18.1%) at the end of follow-up. ResultsThere were no statistically significant differences between second revision rates of the three volume groups. Adjusted hazard ratio for second revision were 0.97 (Confidence Interval (CI) 0.86 to 1.11) for hospitals with 13 to 24 cases/year and 0.94 (CI 0.83 to 1.07) with ≥25 cases/year compared to low volume (≤12 cases/year). Type of revision did not influence second revision rate. ConclusionSecond revision rate of R-KA does not seem to be dependent on hospital volume or type of revision in the Netherlands. Level of evidenceLevel IV, Observational registry study.

Ventilation strategies and children's perception of the indoor environment in Swedish primary school classrooms

This study explored the relationship between children's subjective perception of indoor environmental quality in classrooms, measured thermal and air quality factors, and the type of ventilation. Environmental data were collected in 45 classrooms in 23 primary schools in Sweden during the heating season. Schools with three types of ventilation were recruited: natural or exhaust ventilation (category A), balanced supply-exhaust with constant air volume (category B), and balanced supply-exhaust with variable air volume or demand-controlled ventilation (category C). 796 children (8–14 years of age) answered a questionnaire about their perception of the classroom's indoor environment. Based on ten dichotomous questions, the children's overall perceptions and subjective well-being was scored (“Individual score”) from worst (0) to best (10) perception. A Perception Index (PI) was calculated as the arithmetic mean of the Individual scores from all children in a given classroom. We did not find statistically significant differences in the Individual scores or PI between the three ventilation categories. However, the PI of classrooms with ventilation category A, which also had lower ventilation rates and higher concentrations of pollutants, was noticeably lower than that in classrooms with ventilation category B or C. Correlations between the PI and most of the measured environmental parameters or the individual questions about perception were weak and not significant. The PI may be improved by including factors not considered in this study, such as those related to acoustic and lighting conditions.