29 research outputs found

    Helium, Oxygen, Proton, and Electron (HOPE) Mass Spectrometer for the Radiation Belt Storm Probes Mission

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    The HOPE mass spectrometer of the Radiation Belt Storm Probes (RBSP) mission (renamed the Van Allen Probes) is designed to measure the in situ plasma ion and electron fluxes over 4π sr at each RBSP spacecraft within the terrestrial radiation belts. The scientific goal is to understand the underlying physical processes that govern the radiation belt structure and dynamics. Spectral measurements for both ions and electrons are acquired over 1 eV to 50 keV in 36 log-spaced steps at an energy resolution ΔE FWHM/E≈15 %. The dominant ion species (H+, He+, and O+) of the magnetosphere are identified using foil-based time-of-flight (TOF) mass spectrometry with channel electron multiplier (CEM) detectors. Angular measurements are derived using five polar pixels coplanar with the spacecraft spin axis, and up to 16 azimuthal bins are acquired for each polar pixel over time as the spacecraft spins. Ion and electron measurements are acquired on alternate spacecraft spins. HOPE incorporates several new methods to minimize and monitor the background induced by penetrating particles in the harsh environment of the radiation belts. The absolute efficiencies of detection are continuously monitored, enabling precise, quantitative measurements of electron and ion fluxes and ion species abundances throughout the mission. We describe the engineering approaches for plasma measurements in the radiation belts and present summaries of HOPE measurement strategy and performance

    Association between the Preoperative Standard Uptake Value (SUV) and Survival Outcomes after Robotic-Assisted Segmentectomy for Resectable Non-Small Cell Lung Cancer (NSCLC)

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    Background: Lung-sparing procedures, specifically segmentectomies and wedge resections, have increased over the years to treat early-stage non-small cell lung cancer (NSCLC). We investigate here the perioperative and long-term outcomes of patients who underwent robotic-assisted segmentectomy (RAS) at an NCI-designated cancer center and aim to show associations between the preoperative standard update value (SUV) to tumor stage, recurrence patterns, and overall survival. Methods: A retrospective analysis was performed on 166 consecutive patients who underwent RAS at a single institution from 2010 to 2021. Of this number, 121 robotic-assisted segmentectomies were performed for primary NSCLC, and a total of 101 patients were evaluated with a PET-CT scan. The SUV from the primary tumor was determined from the PET-CT. The clinical, surgical, and pathologic profiles and perioperative outcomes were summarized via descriptive statistics. Numerical variables were described as the median and interquartile range because all numerical variables were not normally distributed as assessed by the Shapiro–Wilk test of normality. Categorical variables were described as the count and proportion. Chi-square or Fisher’s exact test was used for association. The main outcomes were overall survival (OS) and recurrence-free survival (RFS). Kaplan–Meier (KM) curves were constructed to visualize the OS and RFS, which were also stratified according to tumor histology, the pathologic stage, and standard uptake value. A log-rank test for the equality of survival curves was performed to determine significant differences between groups. Results: The most common postoperative complications were atrial fibrillation (8.8%, 9/102), persistent air leak (7.84%, 8/102), and pneumonia (4.9%, 5/102). The median operative duration was 168.5 min (IQR 59), while the median estimated blood loss was 50 mL (IQR 125). The conversion rate to thoracotomy in this cohort was 3.9% (4/102). Intraoperative complications occurred in 2.9% (3/102). The median hospital length of stay was 3 days (IQR 3). The median chest tube duration was 3 days (IQR 2), but 4.9% (5/102) of patients were sent home with a chest tube. The recurrence for this cohort was 28.4% (29/102). The time to recurrence was 353 days (IQR 504), while the time to mortality was 505 days (IQR 761). The NSCLC patients were divided into the following two groups: low SUV (n = 55) and high SUV (≥5, n = 47). Statistically significant associations were noted between SUV and the tumor histology (p = 0.019), tumor grade (p = 0.002), lymph-vascular invasion (p = 0.029), viscera-pleural invasion (p = 0.008), recurrence (p p = 0.047). KM survival analysis showed significant differences in the curves for OS (log-rank p-value 0.0204) and RFS (log-rank p-value 0.0034) between the SUV groups. Conclusion: Robotic-assisted segmentectomy for NSCLC has reasonable perioperative and oncologic outcomes. Furthermore, we demonstrate here the prognostic implication of preoperative SUV to pathologic outcomes, recurrence-free survival, and overall survival

    Changes in Perioperative Outcomes after Robotic-Assisted Pulmonary Lobectomy during the COVID-19 Era.

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    BACKGROUND: The COVID-19 pandemic presented patients with barriers to receiving healthcare. We sought to determine whether changes in healthcare access and practice during the pandemic affected perioperative outcomes after robotic-assisted pulmonary lobectomy (RAPL). METHODS: We retrospectively analyzed 721 consecutive patients who underwent RAPL. With March 1 RESULTS: COVID-19-Era patients had significantly higher preoperative FEV1%, lower cumulative smoking history and higher incidences of preoperative atrial fibrillation, peripheral vascular disease (PVD), and bleeding disorders compared to PreCOVID-19 patients. COVID-19-Era patients had lower intraoperative estimated blood loss (EBL), reduced incidence of new-onset postoperative atrial fibrillation (POAF), but higher incidence of effusion or empyema postoperatively. Overall postoperative complication rates between the groups were similar. Older age, increased EBL, lower preoperative FEV1%, and preoperative COPD are all predictive of an increased risk for postoperative complication. CONCLUSIONS: COVID-19-Era patients having lower EBL and less new-onset POAF, despite greater incidences of multiple preoperative comorbidities, demonstrates that RAPL is safe during the COVID-19 era. Risk factors for development of postoperative effusion should be determined to minimize risk of empyema in COVID-19-Era patients. Age, preoperative FEV1%, COPD, and EBL should all be considered when planning for complication risk

    A High Preoperative Blood Urea Nitrogen to Serum Albumin Ratio Does Not Predict Worse Outcomes Following the Robotic-Assisted Pulmonary Lobectomy for Lung Cancer.

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    BACKGROUND: The blood urea nitrogen to serum albumin ratio (BAR) is an emerging prognostic parameter of interest. The utility of BAR as a prognostic factor has not been analyzed in lung cancer patients undergoing pulmonary lobectomy. We evaluated the ability of High BAR to predict worse outcomes after robotic-assisted pulmonary lobectomy (RAPL) for lung cancer. METHODS: We retrospectively analyzed 400 patients who underwent RAPL from September 2010 to March 2022 by one surgeon. Patients were stratified by Low BAR ( RESULTS: Receiver operator curves (ROC) confirmed that 6.25 was an optimal threshold for estimating mortality based on Low and High BAR. There were no differences in surgical complications or outcomes between the Low and High BAR groups. The ability of BAR to predict 30-day mortality was evaluated with the area under the curve (AUC) analysis, which showed that higher BAR could not predict mortality (AUC=0.655; 95% CI, 0.435-0.875; CONCLUSION: High BAR did not predict worse outcomes after RAPL for lung cancer in our study. Further studies are needed to better determine the prognostic ability of BAR in lower-risk populations

    Changes in Perioperative Outcomes after Robotic-Assisted Pulmonary Lobectomy during the COVID-19 Era

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    Background: The COVID-19 pandemic presented patients with barriers to receiving healthcare. We sought to determine whether changes in healthcare access and practice during the pandemic affected perioperative outcomes after robotic-assisted pulmonary lobectomy (RAPL). Methods: We retrospectively analyzed 721 consecutive patients who underwent RAPL. With March 1st, 2020, defining the start of the COVID-19 pandemic, we grouped 638 patients as “PreCOVID-19” and 83 patients as “COVID-19-Era” based on surgical date. Demographics, comorbidities, tumor characteristics, intraoperative complications, morbidity, and mortality were analyzed. Variables were compared utilizing Student's t-test, Wilcoxon rank-sum test, and Chi-square (or Fisher's exact) test, with significance at p≤0.05. Multivariable generalized linear regression was used to investigate predictors of postoperative complication. Results: COVID-19-Era patients had significantly higher preoperative FEV1%, lower cumulative smoking history and higher incidences of preoperative atrial fibrillation, peripheral vascular disease (PVD), and bleeding disorders compared to PreCOVID-19 patients. COVID-19-Era patients had lower intraoperative estimated blood loss (EBL), reduced incidence of new-onset postoperative atrial fibrillation (POAF), but higher incidence of effusion or empyema postoperatively. Overall postoperative complication rates between the groups were similar. Older age, increased EBL, lower preoperative FEV1%, and preoperative COPD are all predictive of an increased risk for postoperative complication. Conclusions: COVID-19-Era patients having lower EBL and less new-onset POAF, despite greater incidences of multiple preoperative comorbidities, demonstrates that RAPL is safe during the COVID-19 era. Risk factors for development of postoperative effusion should be determined to minimize risk of empyema in COVID-19-Era patients. Age, preoperative FEV1%, COPD, and EBL should all be considered when planning for complication risk
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