scholarly journals Comparison of two continuous non-invasive haemodynamic monitoring techniques in the perioperative setting

2019 ◽  
Vol 26 (1) ◽  
pp. 31-37
Author(s):  
Jonė Jackevičiūtė ◽  
Greta Kraujalytė ◽  
Inna Jaremko ◽  
Vilija Stremaitytė ◽  
Jūratė Gudaitytė

Background. The aim of the study was to identify the accuracy of and agreement between two non-invasive haemodynamic monitoring techniques in the perioperative setting – thoracic electrical bioimpedance (TEB) and Edwards Lifesciences ClearSight system (CS). Materials and methods. The study included ten patients. Parametric quantitative data were expressed as mean ± SD. The ShapiroWilk test was used to test the normality of the distributions. A linear regression model was used to measure the strength of the linear relationship between TEB and CS. Bland-Altman analysis was performed to assess the mean difference, precision, and the limits of agreements (LOA). The Critchley and Critchley method was used to calculate the percentage error (PE), and if

2021 ◽  
Vol 22 (Supplement_2) ◽  
Author(s):  
V Vidal Urrutia ◽  
A Cubillos-Arango ◽  
P Garcia-Gonzalez ◽  
J Gradoli-Palmero ◽  
J Nunez-Villota ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Introduction. Pulmonary vascular resistance (PVR) is a hemodynamic parameter with important diagnostic and prognostic implications in patients with heart failure. Currently the gold standard technique for its quantification is right heart catheterization (RHC). However, cardiovascular magnetic resonance imaging (CMR) has been postulated as a non-invasive alternative for its estimation. The aim of this study is to assess the accuracy of a non-invasive model of PVR estimated by CMR in a specific subgroup of patients with acute heart failure (AHF). Methods. Between January 2014 and December 2018, 108 patients with AHF who underwent RHC and CMR on the same day were prospectively included. PVR was assessed by CMR using the model: 19.38 - [4.62 x Ln mean pulmonary artery velocity - 0.08 x right ventricular ejection fraction (RVEF)]. During RHC, PVR were calculated using the ratio between transpulmonary gradient and cardiac output. We evaluated their correlation using the Spearman correlation coefficient, receiver operating characteristic [ROC] curves, and Bland-Altman analysis. Results. The mean age of our cohort was 65 ± 11 years and 64.8% were male. The median PVR (Wood Units, WU) assessed by CMR and RHC were 5.1 WU (3.4 - 6.8) and 3 WU (1.5 - 3.9); p < 0.001, respectively. A weak correlation was observed between the PVR obtained by RHC and those obtained by CMR in our population (r = 0.21; p = 0.02). On Bland-Altman analysis, the mean bias was -1.7, and the 95% limits of agreement ranged from -10.02 to 6.6 WU. The area under the ROC curve for PVR assessed by CMR to detect PVR ³3 WU was 0.57, 95% confidence interval (CI): 0.47-0.68. Conclusions. In patients with AHF, the non-invasive estimation of PVR using CMR shows poor accuracy, as well as a limited capacity to discriminate increased PVR values.


2016 ◽  
Vol 17 (4) ◽  
pp. 294-299 ◽  
Author(s):  
Mohammad Y Hajeer ◽  
Ahmad L Maroua ◽  
Mowaffak Ajaj

ABSTRACT Objective To evaluate the accuracy and reproducibility of linear measurements made on cone-beam computed tomography (CBCT)-derived digital models. Materials and methods A total of 25 patients (44% female, 18.7 ± 4 years) who had CBCT images for diagnostic purposes were included. Plaster models were obtained and digital models were extracted from CBCT scans. Seven linear measurements from predetermined landmarks were measured and analyzed on plaster models and the corresponding digital models. The measurements included arch length and width at different sites. Paired t test and Bland–Altman analysis were used to evaluate the accuracy of measurements on digital models compared to the plaster models. Also, intraclass correlation coefficients (ICCs) were used to evaluate the reproducibility of the measurements in order to assess the intraobserver reliability. Results The statistical analysis showed significant differences on 5 out of 14 variables, and the mean differences ranged from −0.48 to 0.51 mm. The Bland–Altman analysis revealed that the mean difference between variables was (0.14 ± 0.56) and (0.05 ± 0.96) mm and limits of agreement between the two methods ranged from −1.2 to 0.96 and from −1.8 to 1.9 mm in the maxilla and the mandible, respectively. The intraobserver reliability values were determined for all 14 variables of two types of models separately. The mean ICC value for the plaster models was 0.984 (0.924–0.999), while it was 0.946 for the CBCT models (range from 0.850 to 0.985). Conclusion Linear measurements obtained from the CBCTderived models appeared to have a high level of accuracy and reproducibility. How to cite this article Maroua AL, Ajaj M, Hajeer MY. The Accuracy and Reproducibility of Linear Measurements Made on CBCT-derived Digital Models. J Contemp Dent Pract 2016;17(4):294-299.


Author(s):  
Mera Usman Muhammed ◽  
Mayaki Abubakar Musa ◽  
Gambo Abdulrahman Abdullahi

This study was carried out to compare the digital rectal (DR) thermometer with non-contact infrared thermometer (IRT) measurements at two locations on the face in some large animal species. Two hundred and forty (240) animals comprising of equal numbers of three species (cattle, camel and horses) of varying age and either sex was used. The IR temperature was taken from two sites [frontal (FIRT) and temporal (TIRT) region] on the animal face. The mean IR temperatures (FIRT and TIRT) were higher than the RT in all the animal species. The two thermometers correlate poorly in all the animal species. Bland-Altman analysis showed high biases and limits of agreement not acceptable for clinical purposes. In conclusion, IRT seems to offer a quick and easy way to determine the animal temperature but clinically it cannot be used interchangeably with DR thermometer at the moment for body temperature measurement in these animal species.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Ziming Liu ◽  
Emmanuel Eric Pazo ◽  
Hong Ye ◽  
Cui Yu ◽  
Ling Xu ◽  
...  

Purpose. To assess the repeatability and agreement of refractive measurements using 2WIN-S photoscreening with the gold-standard cycloplegic retinoscope refraction. Design. Single centre, cross-sectional study. Methods. Spherical, cylindrical, axis, and spherical equivalent of 194 bilateral eyes of 97 children were assessed using a retinoscope and 2WIN-S. One week later, another operator repeated the 2WIN-S measurements. The primary outcome measures were to assess the repeatability and agreement between spherical equivalent, J0, and J45 readings of 2WIN-S. The repeatability of measurements was assessed by the within-subject standard deviation (2.77 Sw) and intraclass correlation coefficient (ICC). The agreement between devices was assessed using 95% limits of agreement. The extent of the agreement between cycloplegic retinoscopy and noncycloplegic 2WIN-S measurements was assessed using Bland–Altman analysis. Results. The mean age ± SD was 10.3 ± 2.46 year (range, 4–14 years). The sphere, cylinder, and spherical equivalent measurements were found to be consistent with both apparatus (r value >0.86). ICC for SE, J0, and J45 was 0.900, 0.666, and 0.639, respectively; Sw for SE, J0, and J45 was 0.61D, 0.30D, and 0.31D, respectively; Bland–Altman analysis of retinoscopy with cycloplegia and 2WIN-S for SE was 184/194 (95%) in 95% confidence interval, and the mean value was 0.46. J0 was 184/194 (95%), and the mean value is −0.04. J45 was 181/194 (93%), and the mean value is −0.15. Conclusion. The objective refractive measurement of 2WIN-S had good reliability and high agreement with the gold-standard retinoscopy refraction in children and adolescents. While consistency was observed, it is essential to take into consideration that it is a screening tool.


2019 ◽  
Vol 43 (6) ◽  
pp. 379-384
Author(s):  
Qi Zhang ◽  
Feng Zhuang ◽  
Qichen Fan ◽  
Wenyan Yu ◽  
Feng Ding

Aim: This study aimed to investigate whether effluent ionized calcium was an appropriate indicator to assess anticoagulant effect in continuous renal replacement therapy with regional citrate anticoagulation instead of post-filter ionized calcium. Methods: In total, 48 paired samples of effluent fluid and post-filter blood were obtained from critically ill patients who required continuous renal replacement therapy. All samples were taken for ionized calcium measurements and were assessed by point-of-care analyzer. Correlations and agreements between two methods were performed by Pearson linear analysis and Bland–Altman analysis accordingly. Results: The mean post-filter ionized calcium was 0.42 ± 0.12 mmol/L, and mean ionized calcium level of effluent fluid was 0.39 ± 0.11 mmol/L. The ionized calcium level of effluent fluid was significantly correlated with post-filter ionized calcium in all continuous renal replacement therapy patients. Bland–Altman analysis showed that the mean difference of ionized calcium between two sampling sites in all continuous renal replacement therapy patients was −0.02 mmol/L with 95% confidence interval ranging from −0.09 to 0.04 mmol/L. The significant correlations and agreements were also demonstrated in continuous veno-venous hemofiltration, continuous veno-venous hemodialysis, and continuous veno-venous hemodiafiltration modalities separately. Conclusion: The effluent ionized calcium could be a considerable substitute for post-filter ionized calcium to monitor the validity of regional citrate anticoagulation in continuous renal replacement therapy with less blood loss.


2015 ◽  
Vol 18 (01) ◽  
pp. 1550003
Author(s):  
Travis M. Falconer ◽  
Julie Headford ◽  
Stephen Edmondston ◽  
Piers J. Yates

The Oxford Hip Score (OHS) and Oxford Knee Score (OKS) are validated, reliable and reproducible outcome measures, however their use retrospectively has not been examined. The aim of this prospective cohort study was to examine the accuracy and reliability of patients' ability to recall their OHS and OKS in a retrospective manner. A total of 137 patients undergoing primary hip (40) or primary knee (97) arthroplasty with a mean age of 70.8 years (range, 47–88) and a mean time to follow up of 27.2 months (range, 6–46) were included in the study. The mean retrospective OHS and OKS decreased compared to the pre-operative score (OHS = 1.6 ± SD, p = 0.36, OKS = 4.7 ± SD, p < 0.001). There was only a weak positive relationship between the actual pre-operative scores and the retrospective scores (OHS: r2 = 0.30, OKS: r2 = 0.19). Bland–Altman analysis demonstrated 95% limits of agreement between scores of -19.9 to 23.1 for the OHS and -15.3 to 24.8 for the OKS. This study shows that patients are poor at retrospectively recalling their pre-operative OHS and OKS and therefore these scores should not be used in a retrospective manner.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
F R Pluchinotta ◽  
M Panebianco ◽  
L Piazza ◽  
P Tarzia ◽  
L Fusini ◽  
...  

Abstract Background Cardiac MR (CMR) is the gold standard for right ventricular (RV) quantification. Three-dimensional echo (3DE) is a relatively new technique which may offer a rapid alternative for the examination of the right heart. The purpose of this study was to investigate the clinical significance and interchangeability of these modalities to evaluate patients with congenital heart disease (CHD) who underwent percutaneous pulmonary valve implantation (PPVI) for RV outflow tract dysfunction. Methods 36 patients who underwent PPVI were evaluated with 3DE and CMR to quantify the RV. RV volumes and ejection fraction (EF) were measured for both imaging techniques with commercially available softwares (Tomtec-Germany for 3DE and Medimatic-Netherlands for CMR data). Paired t-test, Bland-Altman analysis, and Pearson's correlation analysis were used as most appropriate to compare both measured techniques with CMR regarded as the reference standard. Results 86% of the patients (31 patients) had adequate image quality on 3DE and was included in the study. Patients underwent both 3D echo and CMR within a mean of 9 days of each other and at a mean time of 3 years after PPVI. Compared to CMR, 3D echo significantly underestimated volumes in all patients and overestimate RV ejection fraction (EF). Mean RV End-diastolic Volumes (EDV) and End-Systolic Volumes (ESV) were significantly greater when measured by CMR compared to 3D echo (EDV: 99 ml/m2 vs. 85 ml/m2; p<0.01, ESV: 52 ml/m2 vs. 41 ml/m2; p<0.01). Mean RV EF was lower when measured by CMR compared to 3D echo (48% vs 52%; p<0.05). Linear regression analysis showed high correlation coefficients between 3DE and CMR (r=0,68 for EDV, r=0,62 for ESV, and r=0,57 for EF; p<0.001). Bland-Altman analysis demonstrated that for both RV EDV and RV ESV there was a significant and systematic under-estimation of volume by 3D echo compared to CMR. Both 3DE and CMR measurements were found to be highly reproducible in terms of intra-observer variability. Conclusions Statistically significant and clinically meaningful differences in volumetric measurements were observed between 3DE and CMR in the evaluation of RV volumes and function in patients with CHD after PPVI. Despite linear regression and Bland-Altman analysis showed that the two techniques are related and present some degree of agreement, 3D Echocardiography systematically underestimates volumes and overestimates EF and this would have to be considered in the clinical practice.


PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e4132 ◽  
Author(s):  
Rashad Zayat ◽  
Andreas Goetzenich ◽  
Ju-Yeon Lee ◽  
HeeJung Kang ◽  
So-Hyun Jansen-Park ◽  
...  

BackgroundBedside non-invasive techniques, such as radial artery tonometry, to estimate hemodynamic parameters have gained increased relevance as an attractive alternative and efficient method to measure hemodynamics in outpatient departments. For our pilot study, we sought to compare cardiac output (CO), and stroke volume (SV) estimated from a radial artery tonometry blood pressure pulse analyzer (BPPA) (DMP-Life, DAEYOMEDI Co., Gyeonggi-do, South Korea) to pulsed-wave Doppler (PWD) echocardiography derived parameters.MethodsFrom January 2015 to December 2016, all patients scheduled for coronary artery bypass (CABG) surgery at our department were screened. Exclusion criteria were, inter alia, moderate to severe aortic- or Mitral valve disease and peripheral arterial disease (PAD) > stage II. One hundred and seven patients were included (mean age 66.1 ± 9.9, 15 females, mean BMI 27.2 ± 4.1 kg/m2). All patients had pre-operative transthoracic echocardiography (TTE). We measured the hemodynamic parameters with the BPPA from the radial artery, randomly before or after TTE. For the comparison between the measurement methods we used the Bland-Altman test and Pearson correlation.ResultsMean TTE-CO was 5.1 ± 0.96 L/min, and the mean BPPA-CO was 5.2 ± 0.85 L/min. The Bland-Altman analysis for CO revealed a bias of −0.13 L/min and SD of 0.90 L/min with upper and lower limits of agreement of −1.91 and +1.64 L/min. The correlation of CO measurements between DMP-life and TTE was poor (r = 0.501,p < 0.0001). The mean TTE-SV was 71.3 ± 16.2 mL and the mean BPPA-SV was 73.8 ± 19.2 mL. SV measurements correlated very well between the two methods (r = 0.900,p < 0.0001). The Bland-Altman analysis for SV revealed a bias of −2.54 mL and SD of ±8.42 mL and upper and lower limits of agreement of −19.05 and +13.96 mL, respectively.ConclusionOur study shows for the first time that the DMP-life tonometry device measures SV and CO with reasonable accuracy and precision of agreement compared with TTE in preoperative cardiothoracic surgery patients. Tonometry BPPA are relatively quick and simple measuring devices, which facilitate the collection of cardiac and hemodynamic information. Further studies with a larger number of patients and with repeated measurements are in progress to test the reliability and repeatability of DMP-Life system.


2020 ◽  
Author(s):  
Marc Wirden ◽  
Linda Feghoul ◽  
Mélanie Bertine ◽  
Marie-Laure Nere ◽  
Quentin Le Hingrat ◽  
...  

ABSTRACTBackgroundRT-PCR testing is crucial in the diagnostic of SARS-CoV-2 infection. The use of reliable and comparable PCR assays is a cornerstone to allow use of different PCR assays depending on the local equipment. In this work, we provide a comparison of the Cobas® (Roche) and the RealStar® assay (Altona).MethodsAssessment of the two assays was performed prospectively in three reference Parisians hospitals, using 170 clinical samples. They were tested with the Cobas® assay, selected to obtain a distribution of cycle threshold (Ct) as large as possible, and tested with the RealStar assay with three largely available extraction platforms: QIAsymphony (Qiagen), MagNAPure (Roche) and NucliSENS-easyMag (BioMérieux).ResultsOverall, the agreement (positive for at least one gene) was 76%. This rate differed considerably depending on the Cobas Ct values for gene E: below 35 (n = 91), the concordance was 99%. Regarding the positive Ct values, linear regression analysis showed a determination correlation (R2) of 0.88 and the Deming regression line revealed a strong correlation with a slope of 1.023 and an intercept of -3.9. Bland-Altman analysis showed that the mean difference (Cobas® minus RealStar®) was + 3.3 Ct, with a SD of + 2.3 Ct.ConclusionsIn this comparison, both RealStar® and Cobas® assays provided comparable qualitative results and a high correlation when both tests were positive. Discrepancies exist after 35 Ct and varied depending on the extraction system used for the RealStar® assay, probably due to a low viral load close to the detection limit of both assays.


Author(s):  
Francesco Lo Re ◽  
Sandro Sponga ◽  
Chiara Nalli ◽  
Antonella Zucchetto ◽  
Ugolino Livi ◽  
...  

Aim The study aim is the validation of two algorithms of Limited Sampling Strategy (LSS) for the quantification of Mycophenolic Acid (MPA) Area under the plasma concentration-time curve from 0 to 12h (AUC0-12h) in a cohort of non-selected Heart Transplant (HTx) recipients treated, as standard clinical practice, with Mycophenolate Mofetil (MMF) combined with Cyclosporine (CsA), or Tacrolimus (TAC). These two LSSs were previously tested and validated by Baraldo et al. in a cohort of selected HTx recipients 1,2. The value of MPA AUC0-12h (real and estimated with LSSs) among non-rejected (NR) and rejected (R) patients were evaluated. Methods Linear regression and Bland Altman Analysis validated two LSSs methods (named LSS3 and LSS4 by number of blood samples used). The value of MPA AUC0-12h between NR and R patients were compared by Mann-Whitney test. Results The validation reports positive results for LSS3 and LSS4 according to linear regression (r=0.91 and 0.94 and R2=0.84 and 0.88, respectively) and Bland Altman Analysis (p=0.04 and 0.04). There was a difference of borderline statistically significance (p=0.06) for the median value of MPA AUC0-12h (mg×h/L) between NR and R patients (46.60; Interquartile Range (IQR): 34.80-64.10 vs 33.70; IQR: 23.60-48.25); whereas the difference was statistically significant for both LSS3 and LSS4 (p=0.03 and 0.04). Conclusion The capability of these two LSSs to estimate MPA AUC0-12h in cohort of non-selected HTx recipients and the suggestion of a significant difference on MPA AUC0-12h between NR and R patients, confirm the importance of MPA quantification in the clinical field.


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