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1.

Background

Volatile propofol can be measured in exhaled air and correlates to plasma concentrations with a time delay. However, the effect of single-lung ventilation on exhaled propofol is unclear. Therefore, our goal was to evaluate exhaled propofol concentrations during single-lung compared to double-lung ventilation using double-lumen tubes.

Methods

In a first step, we quantified adhesion of volatile propofol to the inner surface of double-lumen tubes during double- and single-lumen ventilation in vitro. In a second step, we enrolled 30 patients scheduled for lung surgery in two study centers. Anesthesia was provided with propofol and remifentanil. We utilized left-sided double-lumen tubes to separately ventilate each lung. Exhaled propofol concentrations were measured at 1-min intervals and plasma for propofol analyses was sampled every 20 min. To eliminate the influence of dosing on volatile propofol concentration, exhalation rate was normalized to plasma concentration.

Results

In-vitro ventilation of double-lumen tubes resulted in increasing propofol concentrations at the distal end of the tube over time. In vitro clamping the bronchial lumen led to an even more pronounced increase (Δ AUC +62%) in propofol gas concentration over time. Normalized propofol exhalation during lung surgery was 31% higher during single-lung compared to double-lung ventilation.

Conclusion

During single-lung ventilation, propofol concentration in exhaled air, in contrast to our expectations, increased by approximately one third. However, this observation might not be affected by change in perfusion-ventilation during single-lung ventilation but rather arises from reduced propofol absorption on the inner surface area of the double-lumen tube. Thus, it is only possible to utilize exhaled propofol concentration to a limited extent during single-lung ventilation.

Registration of Clinical Trial

DRKS-ID DRKS00014788 ( www.drks.de ).  相似文献   
2.

Introduction

Bronchiolitis Obliterans Syndrome (BOS) is a debilitating disease with limited treatment options that threatens both the quality of life and long-term survival of lung transplant (LTx) recipients. This retrospective longitudinal case–control study was performed to compare the long-term functional evolution of LTx recipients with and without BOS.

Methods

Twenty-four LTx recipients with BOS (BOS=Cases) and 24 without BOS (NON-BOS=Controls) were selected and individually matched according to age, gender, diagnosis and LTx characteristics. Measurements of 6-minute walking distance (6MWD), symptoms of dyspnea (BORG CR-10 scale), and comprehensive pulmonary function testing were performed before LTx and at annual follow-up assessments after LTx.

Results

Peak FEV1 after LTx was similar in both groups [FEV1 (% predicted) 101 ± 25 vs. 101 ± 31, p = 0.96] and BOS diagnosis in cases was established 3.6 ± 2.5 years after LTx. At the final follow-up assessment (6.5 ± 3.2 years after LTx) FEV1 (% predicted) was 86 ± 34 in NON-BOS vs. 44 ± 17 in BOS (p < 0.001). Evolution of 6MWD was different between groups (group by time interaction: p = 0.002). Borg dyspnea scores were also significantly different between groups at the final evaluation (NON-BOS 3.3 ± 1.7 vs. BOS 5.0 ± 2.2; p = 0.024).

Conclusions

We observed gradual reductions in functional exercise capacity and increasing symptoms of dyspnea in patients who developed BOS after LTx. As such, prospective studies seem warranted to explore whether rehabilitative interventions might be useful to improve symptoms and slow down deterioration of exercise capacity in these patients from the onset of BOS.  相似文献   
3.
Molecular Imaging and Biology - Multidrug resistance-associated proteins (MRPs) mediate the hepatobiliary and renal excretion of many drugs and drug conjugates. The positron emission tomography...  相似文献   
4.
Journal of Neuro-Oncology - Intra-arterial (IA) delivery of therapeutic agents across the blood-brain barrier (BBB) is an evolving strategy which enables the distribution of high concentration...  相似文献   
5.

Objectives

The Mental Health Index (MHI) is widely used as a measure of mental health status, but has not been evaluated in the geriatric oncology population. This study evaluated the MHI-17 in a geriatric oncology population, to establish validity and scoring rules.

Materials and Methods

The Carolina Senior Registry (NCT01137825) was used to obtain data for 686 patients with cancer 65 and older who completed the MHI-17. The 17-item patient-reported measure produces one total score summing across four domains: anxiety, depression, positive affect, and sense of belonging. Cronbach's alpha (α), confirmatory factor analyses (CFA), item-response theory (IRT) analyses, and differential item functioning (DIF) analyses were used to evaluate internal consistency and validity.

Results and Discussion

The revised MHI retained the 13 best-fitting items from the MHI-17 and resulted in a final model that included two subscales: anxiety (four items, RMSEA 0.11; CFI 0.99; TLI 0.98) and depression (9 items, RMSEA 0.10; CFI 0.96; TL 0.95). IRT analyses of the four anxiety items indicated good fit (RMSEA 0.08) and precise measurement of adults with poor mental health, and the nine depression items also fit well (RMSEA 0.05). No meaningful differences were found by sex, education, or treatment stage. Scores were developed to provide meaningful norms. The new MHI-13 is a shorter, more accurate way to assess mental health in older adults with cancer and most importantly allows clinicians to separately identify anxiety and/or depression - a clinically important distinction as treatment differs among these two types of mental health impairment.  相似文献   
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9.

Aim

VE1 is a monoclonal antibody detecting mutant BRAFV600E protein by immunohistochemistry. Here we aim to determine the inter-observer agreement and concordance of VE1 with mutational status, investigate heterogeneity in colorectal cancers and metastases and determine the prognostic effect of VE1 in colorectal cancer patients.

Methods

Concordance of VE1 with mutational status and inter-observer agreement were tested on a pilot cohort of colorectal cancers (n = 34), melanomas (n = 23) and thyroid cancers (n = 8). Two prognostic cohorts were evaluated (n = 259, Cohort 1 and n = 226, Cohort 2) by multiple-punch tissue microarrays. VE1 staining on preoperative biopsies (n = 118 patients) was compared to expression in resections. Primary tumors and metastases from 13 patients were tested for VE1 heterogeneity using a tissue microarray generated from all available blocks (n = 100 blocks).

Results

Inter-observer agreement was 100% (kappa = 1.0). Concordance between VE1 and V600E mutation was 98.5%. Cohort 1: VE1 positivity (seen in 13.5%) was associated with older age (p = 0.0175) and MLH1 deficiency (p < 0.0001). Cohort 2: VE1 positivity (seen in 12.8%) was associated with female gender (p = 0.0016), right-sided tumor location (p < 0.0001), higher tumor grade (p < 0.0001) and mismatch repair (MMR)-deficiency (p < 0.0001). In survival analysis, MMR status and postoperative therapy were identified as possible confounding factors. Adjusting for these features, VE1 was an unfavorable prognostic factor. Preoperative biopsy staining matched resections in all cases except one. No heterogeneity was found across any primary/metastatic tumor blocks.

Conclusion

VE1 is highly concordant for V600E and homogeneously expressed suggesting staining can be analysed on resection specimens, preoperative biopsies, metastatic lesions and tissue microarrays.  相似文献   
10.
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