scholarly journals Quantitative assessment of pulmonary artery occlusion using lung dynamic perfusion CT

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Laura Jimenez-Juan ◽  
Hatem Mehrez ◽  
Chris Dey ◽  
Shabnam Homampour ◽  
Pascal Salazar-Ferrer ◽  
...  

AbstractQuantitative measurement of lung perfusion is a promising tool to evaluate lung pathophysiology as well as to assess disease severity and monitor treatment. However, this novel technique has not been adopted clinically due to various technical and physiological challenges; and it is still in the early developmental phase where the correlation between lung pathophysiology and perfusion maps is being explored. The purpose of this research work is to quantify the impact of pulmonary artery occlusion on lung perfusion indices using lung dynamic perfusion CT (DPCT). We performed Lung DPCT in ten anesthetized, mechanically ventilated juvenile pigs (18.6–20.2 kg) with a range of reversible pulmonary artery occlusions (0%, 40–59%, 60–79%, 80–99%, and 100%) created with a balloon catheter. For each arterial occlusion, DPCT data was analyzed using first-pass kinetics to derive blood flow (BF), blood volume (BV) and mean transit time (MTT) perfusion maps. Two radiologists qualitatively assessed perfusion maps for the presence or absence of perfusion defects. Perfusion maps were also analyzed quantitatively using a linear segmented mixed model to determine the thresholds of arterial occlusion associated with perfusion derangement. Inter-observer agreement was assessed using Kappa statistics. Correlation between arterial occlusion and perfusion indices was evaluated using the Spearman-rank correlation coefficient. Our results determined that perfusion defects were detected qualitatively in BF, BV and MTT perfusion maps for occlusions larger than 55%, 80% and 55% respectively. Inter-observer agreement was very good with Kappa scores > 0.92. Quantitative analysis of the perfusion maps determined the arterial occlusion threshold for perfusion defects was 50%, 76% and 44% for BF, BV and MTT respectively. Spearman-rank correlation coefficients between arterial occlusion and normalized perfusion values were strong (− 0.92, − 0.72, and 0.78 for BF, BV and MTT, respectively) and were statically significant (p < 0.01). These findings demonstrate that lung DPCT enables quantification and stratification of pulmonary artery occlusion into three categories: mild, moderate and severe. Severe (occlusion ≥ 80%) alters all perfusion indices; mild (occlusion < 55%) has no detectable effect. Moderate (occlusion 55–80%) impacts BF and MTT but BV is preserved.

2020 ◽  
Vol 5 (2) ◽  
pp. 588
Author(s):  
Etlida Wati ◽  
Ulva Arini

<p>Documentation is an activity of recording, reporting or recording an event and activities carried out in the form of providing services that are considered important and valuable. One factor that can influence documentation is the nurse's workload. The purpose of this study is to identify the relationship between nurses' workload and the application of documentation in the Hj. Anna Lasmanah Banjarnegara. This  research is quantitative with a cross sectional approach descriptive correlation design. Samples were taken with a total sampling of 65 nurses. Instruments to measure documentation using observation sheets. While the nurse workload instrument uses a questionnaire sheet. The analysis technique uses Spearman Rank correlation. Based on the research results of the workload of a nurse in the hospital room , most of them are in the weight category, as many as 46 respondents (70.8%). Application of nursing care documentation in the hospital room Hj. Anna Lasmanah Banjarnegara, most of them are respondents in the incomplete category as many as 63 respondents (96.9%). There is a significant relationship between nurse workload with the application of documentation, this is evidenced by the results of the Spearman Rank correlation bivariate analysis, which is r = 0.688 with p = 0.000 &lt;0.05. It is hoped that management will motivate nurses to complete the documentation of nursing care</p>


Author(s):  
Yara Falmira Dianira

ABSTRACT An important factor for the success of a CSR program is effective communication. Communication will be effective if it has an impact. If the information is conveyed based on the needs, then the communication will be effective. This study aims to analyze the factors which are related to the effectiveness of CSR communication. This study used a census method to approach 37 participants who received CSR programs. The Data analysis used the Spearman rank correlation for the statistical tests. The results showed that there was a correlation between factors that have the strength of CSR companion communication (level of attractiveness of the companion, quality of message content, and sources of information) which have real communication at the level of understanding of the participants of the Kertajaya Creative Destination (KCD) CSR program. In addition, there is a real correlation the factors that have the strength of CSR companion communication (the level of credibility of the companion, the source information, and the level of the recipient) and having communication at the level of attitudes of participants in the Kertajaya Creative Destination (KCD) CSR program. However, there is no real correlation between CSR companion communication factors and participant actions.Keywords :communication effectiveness, CSR, elements of communication. ABSTRAK Faktor penting dari keberhasilan program CSR adalah komunikasi yang efektif. Komunikasi dikatakan efektif jika menimbulkan dampak. Bila informasi tersampaikan sesuai dengan kebutuhan, maka komunikasi yang dijalankan efektif. Penelitian ini bertujuan untuk menganalisis efektivitas komunikasi pendamping CSR. Penelitian ini menggunakan pendekatan sensus terhadap 37 orang peserta penerima program CSR. Analisis data menggunakan uji statistik korelasi rank Spearman. Hasil penelitian menunjukkan bahwa terdapat hubungan nyata antara faktor efektivitas komunikasi pendamping CSR (derajat daya tarik pendamping, kualaitas isi pesan, dan sumber informasi)  dengan efektivitas komunikasi pada tingkat pemahaman peserta program CSR Kertajaya Creative Destination (KCD). Selain itu, terdapat hubungan nyata antara faktor efektivitas komunikasi pendamping CSR (tingkat kredibilitas pendamping, sumber informasi, dan tingkat penerima) dengan efektivitas komunikasi pada tingkat sikap peserta program CSR Kertajaya Creative Destination (KCD). Namun, tidak terdapat hubungan nyata antara faktor efektivitas komunikasi pendamping CSR dengan tindakan peserta. Kata Kunci : CSR, efektivitas komunikasi, unsur-unsur komunikasi.


Author(s):  
Thomas Scheier ◽  
Stefan P. Kuster ◽  
Mesida Dunic ◽  
Christian Falk ◽  
Hugo Sax ◽  
...  

Abstract Background Understaffing has been previously reported as a risk factor for central line-associated bloodstream infections (CLABSI). No previous study addressed the question whether fluctuations in staffing have an impact on CLABSI incidence. We analyzed prospectively collected CLABSI surveillance data and data on employee turnover of health care workers (HCW) to address this research question. Methods In January 2016, a semiautomatic surveillance system for CLABSI was implemented at the University Hospital Zurich, a 940 bed tertiary care hospital in Switzerland. Monthly incidence rates (CLABSI/1000 catheter days) were calculated and correlations with human resources management-derived data on employee turnover of HCWs (defined as number of leaving HCWs per month divided by the number of employed HCWs) investigated. Results Over a period of 24 months, we detected on the hospital level a positive correlation of CLABSI incidence rates and turnover of nursing personnel (Spearman rank correlation, r = 0.467, P = 0.022). In more detailed analyses on the professional training of nursing personnel, a correlation of CLABSI incidence rates and licensed practical nurses (Spearman rank correlation, r = 0.26, P = 0.038) or registered nurses (r = 0.471, P = 0.021) was found. Physician turnover did not correlate with CLABSI incidence (Spearman rank correlation, r =  −0.058, P = 0.787). Conclusions Prospectively determined CLABSI incidence correlated positively with the degree of turnover of nurses overall and nurses with advanced training, but not with the turnover of physicians. Efforts to maintain continuity in nursing staff might be helpful for sustained reduction in CLABSI rates.


1957 ◽  
Vol 34 (2) ◽  
pp. 206-227 ◽  
Author(s):  
Bernard L. Brofman ◽  
Bernard L. Charms ◽  
Paul M. Kohn ◽  
John Elder ◽  
Robert Newman ◽  
...  

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 672.2-673
Author(s):  
C. Dykas ◽  
B. H. Rovin ◽  
M. Boesen ◽  
O. Kubassova ◽  
P. Lipsky

Background:Lupus nephritis (LN) remains a significant cause of morbidity and mortality in subjects with Systemic Lupus Erythematosus (SLE). The gold standard for evaluation of LN remains the kidney biopsy, whereas renal function is usually evaluated by eGFR and urinary protein:creatinine ratio. More effective and sensitive methodology is needed to assess LN and also the response to treatment. Functional imaging of the kidney using quantitative techniques has great potential, as it can assess kidney function and pathologic changes non-invasively by evaluating perfusion, oxygenation, cellular density and fibrosis.Objectives:The objective of this study was to develop a multi-modality imaging approach for the evaluation of the spectrum of pathologic changes in LN and to determine when imaging data correlated with renal functionMethods:In this multi-center study (NCT03180021), subjects who were having a standard of care renal biopsy for LN were asked to participate in the imaging evaluation. Local Institutional Review Board approval was obtained, and subjects signed an Informed Consent Form. Dynamic contrast enhanced MRI (DCE-MRI) was employed to detect changes in vascularization and perfusion, Diffusion Weighted Imaging (DWI) to assess interstitial diffusion, T2*Map/BOLD to evaluate tissue oxygenation and T1rho to evaluate fibrosis (Figure 1). Regions of interest were identified in the imaged kidneys and imaging parameters were correlated with measures of renal function, including eGFR and urinary protein: creatinine ratio. In DCE-MRI, we specifically focused on mean Maximum Enhancement (ME), mean Time to Peak Enhancement (TTP) and mean Time of Washout (Twashout) as indicators of renal perfusion.Results:Nine subjects have been evaluated to date and their imaging data assessed for quality. Evaluation of mean data from DCE-MRI has shown a significant correlation between renal perfusion and renal function. For example, as shown in the figure, the 24 hour protein concentration negatively correlated with ME (rs=-0.81, p=0.015), TTP (rs=-0.83, p=0.01) and Twashout (rs=-0.81.p=0.01, Spearman rank correlation). In addition, the protein:creatinine ratio also negatively correlated with ME (rs=-0.79, p=0.02), TTP (rs=-0.74, p=0.04) and Twashout (rs=-0.79, p=0.02, Spearman rank correlation).Conclusion:These initial results have established the feasibility of multi-modality imaging as a tool to evaluate LN in a multi-center study. Moreover, changes in perfusion detected by DCE-MRI significantly correlate with proteinuria and urinary protein:creatinine ratio. These results suggest that multiparameter imaging may contribute useful data in the evaluation of subjects with LN.Figure:Disclosure of Interests:Claire Dykas: None declared, Brad H Rovin Grant/research support from: GSK, Consultant of: GSK, Mikael Boesen Consultant of: AbbVie, AstraZeneca, Eli Lilly, Esaote, Glenmark, Novartis, Pfizer, UCB, Paid instructor for: IAG, Image Analysis Group, AbbVie, Eli Lilly, AstraZeneca, esaote, Glenmark, Novartis, Pfizer, UCB (scientific advisor)., Speakers bureau: Eli Lilly, Esaote, Novartis, Pfizer, UCB, Olga Kubassova Shareholder of: IAG, Image Analysis Group, Consultant of: Novartis, Takeda, Lilly, Employee of: IAG, Image Analysis Group, Peter Lipsky Consultant of: Horizon Therapeutics


2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Peter Diedrich Jensen ◽  
Asbjørn Haaning Nielsen ◽  
Carsten Wiberg Simonsen ◽  
Ulrik Thorngren Baandrup ◽  
Svend Eggert Jensen ◽  
...  

Abstract Background Non-invasive estimation of the cardiac iron concentration (CIC) by T2* cardiovascular magnetic resonance (CMR) has been validated repeatedly and is in widespread clinical use. However, calibration data are limited, and mostly from post-mortem studies. In the present study, we performed an in vivo calibration in a dextran-iron loaded minipig model. Methods R2* (= 1/T2*) was assessed in vivo by 1.5 T CMR in the cardiac septum. Chemical CIC was assessed by inductively coupled plasma-optical emission spectroscopy in endomyocardial catheter biopsies (EMBs) from cardiac septum taken during follow up of 11 minipigs on dextran-iron loading, and also in full-wall biopsies from cardiac septum, taken post-mortem in another 16  minipigs, after completed iron loading. Results A strong correlation could be demonstrated between chemical CIC in 55 EMBs and parallel cardiac T2* (Spearman rank correlation coefficient 0.72, P < 0.001). Regression analysis led to [CIC] = (R2* − 17.16)/41.12 for the calibration equation with CIC in mg/g dry weight and R2* in Hz. An even stronger correlation was found, when chemical CIC was measured by full-wall biopsies from cardiac septum, taken immediately after euthanasia, in connection with the last CMR session after finished iron loading (Spearman rank correlation coefficient 0.95 (P < 0.001). Regression analysis led to the calibration equation [CIC] = (R2* − 17.2)/31.8. Conclusions Calibration of cardiac T2* by EMBs is possible in the minipig model but is less accurate than by full-wall biopsies. Likely explanations are sampling error, variable content of non-iron containing tissue and smaller biopsies, when using catheter biopsies. The results further validate the CMR T2* technique for estimation of cardiac iron in conditions with iron overload and add to the limited calibration data published earlier.


1994 ◽  
Vol 267 (6) ◽  
pp. H2523-H2530 ◽  
Author(s):  
J. L. Unthank ◽  
J. C. Nixon ◽  
M. C. Dalsing

The hemodynamic significance of endothelium-derived relaxing factor (EDRF)-mediated mechanisms in vascular responses to abrupt rat femoral artery occlusion was investigated. Temporary arterial occlusion was produced before and after inhibition of nitric oxide synthase by N omega-nitro-L-arginine methyl ester (L-NAME) or NG-monomethyl-L-arginine (L-NMMA). Iliac artery blood flow and arterial pressures proximal and distal to the occlusion were measured. Normal vascular compensation included a return of resistance to preocclusion levels and a rise in distal pressure to a plateau within 5 min postocclusion. After treatment with L-NAME and L-NMMA, postocclusion resistance remained elevated by 53 and 36%, respectively. Collateral dilation after occlusion, as indicated by the rise in distal pressure, was prevented by L-NAME but not L-NMMA. Increases in adrenergic tone and mean arterial pressure by phenylephrine did not prevent compensation, suggesting the effects of L-NAME and L-NMMA did not result from elevated sympathetic activation or pressure. The results are consistent with the hypothesis that the stimulated release of endothelium-derived relaxing factor mediates the acute vascular compensation to abrupt arterial occlusion.


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