A retrospective analysis of CO2 derived goal-directed perfusion variables under normothermic conditions: do we need to re-evaluate threshold values?

Perfusion ◽  
2020 ◽  
pp. 026765912097299
Author(s):  
Eddy Overdevest ◽  
Evi van den Heuvel ◽  
Marloes van Hoeven
Keyword(s):  
Respiratory Quotient ◽  
Lactate Concentration ◽  
Demographic Variables ◽  
Threshold Values ◽  
Predictive Values ◽  
Cutoff Value ◽  
Maximum Value ◽  
If Current ◽  
Study Population ◽  
Lactate Formation

This study investigated if current predictive values for increased lactate formation: VCO2i > 60 ml min−1 m−2, respiratory quotient (RQ) > 0.90, and DO2/VCO2 < 5.0, are valid under normothermic conditions. CO2 derived parameters were analyzed in 91 patients undergoing normothermic CABG and related to increase of blood lactate concentrations during bypass. In this study population, 85 patients (93%) had a median VCO2i above 60 ml min−1 m−2 and 53 patients (58%) had a DO2/VCO2 ⩽ 5.0. Eighteen patients (20%) had a median RQ ⩾ 0.90, but RQ remained with a maximum value of 0.94 below the biological threshold of 1.0. Increase of lactate concentrations remained without clinical significance and showed weak correlations with VCO2i (rs = 0.277, p = 0.008) and RQ (rs = 0.346, p = 0.001). The cohort was separated for the different CO2 variables by their median value to compare increase in lactate concentration. Patients with a high VCO2i (⩾70 ml min−1 m−2) and a high RQ (⩾0.82) showed significant higher increase in lactate concentration compared to patients with VCO2i < 70 ml min−1 m−2 (p = 0.004), and a RQ < 0.82 (p = 0.012). Groups separated by a median DO2/VCO2 of 4.8 did not show a difference in increase of lactate concentration in blood. In summary, specific CO2 derived threshold values for the prediction of lactate formation, which have been reported in other studies, cannot be confirmed with our findings. However, a CO2 production ⩾70 ml min−1 m−2 and a RQ ⩾ 0.82 in this study population were correlated with increased lactate formation. Because CO2 production during bypass depends on patient temperature, a different cutoff value, that may take into account the influence of demographic variables, should be determined during normothermic CPB.

Diagnostic Accuracy of a New d-Dimer Assay (Sclavo Auto d-Dimer) for Exclusion of Deep Vein Thrombosis in Symptomatic Outpatients

2016 ◽  
Vol 23 (3) ◽  
pp. 221-228 ◽  
Author(s):  
Cristina Legnani ◽  
Michela Cini ◽  
Mirella Frascaro ◽  
Giuseppina Rodorigo ◽  
Michelangelo Sartori ◽  
...  
Keyword(s):  
Deep Vein Thrombosis ◽  
Imaging Techniques ◽  
False Negative ◽  
High Specificity ◽  
Predictive Values ◽  
Cutoff Value ◽  
Vein Thrombosis ◽  
Number Of Patients ◽  
Deep Vein ◽  
D Dimer

In patients presenting non-high clinical pretest probability (PTP), a negative d-dimer can exclude venous thromboembolism without imaging tests. However, each d-dimer assay should be validated in prospective studies. We evaluated an automated d-dimer immunoassay using the Sclavo Auto d-dimer (Sclavo Diagnostics Int, Sovicille, Italy) provided by Dasit Diagnostica (Cornaredo, Milan, Italy). Three hundred two consecutive outpatients suspected of leg deep vein thrombosis (DVT) with non-high PTP were included. The Sclavo Auto d-dimer assay was evaluated on 2 analyzers (Sysmex CA-7000 and Sysmex CS-2100; Sysmex Corporation, Kobe, Japan, provided by Dasit). The cutoff value (200 ng/mL) was established a priori. Prevalence of DVT was 11.9%. Since no false-negative patients were detected, the sensitivity and negative predictive values (NPVs) were 100% (sensitivity = CA-7000: 100% [95% confidence interval, CI: 93.3-100], CS-2100: 100% [95% CI: 93.3-100]; NPV = CA-7000: 100% [95% CI: 97.9-100], CS-2100: 100% [95% CI: 98.0-100]). Specificity was 65.4% (95% CI: 59.4-71.1) and 69.2% (95% CI: 63.3-74.7) for CA-7000 and CS-2100, respectively. Specificity increased when a higher cutoff value (234 ng/mL) was used for patients aged ≥60 years without compromising the safety. Assay reproducibility was satisfactory at concentrations near the cutoff value (total coefficient of variations <10%). In conclusion, the Sclavo Auto d-dimer assay was accurate when used for DVT diagnostic workup in outpatients with non-high PTP. Based on its high sensitivity and NPV, it can be used as a stand-alone test in outpatients with non-high PTP. Given its high specificity, the number of patients in whom further imaging techniques can be avoided increased, improving the yield of the test.

Lactate efflux from exercising human skeletal muscle: role of intracellular P O 2

1998 ◽  
Vol 85 (2) ◽  
pp. 627-634 ◽  
Author(s):  
Russell S. Richardson ◽  
Elizabeth A. Noyszewski ◽  
John S. Leigh ◽  
Peter D. Wagner
Keyword(s):  
Lactate Concentration ◽  
Work Rate ◽  
Incremental Exercise ◽  
Resonance Spectroscopy ◽  
Trained Subjects ◽  
Lactate Formation ◽  
Breathing Room ◽  
Direct Measures ◽  
Maximal Effort

It remains controversial whether lactate formation during progressive dynamic exercise from submaximal to maximal effort is due to muscle hypoxia. To study this question, we used direct measures of arterial and femoral venous lactate concentration, a thermodilution blood flow technique, phosphorus magnetic resonance spectroscopy (MRS), and myoglobin (Mb) saturation measured by 1H nuclear MRS in six trained subjects performing single-leg quadriceps exercise. We calculated net lactate efflux from the muscle and intracellular[Formula: see text] with subjects breathing room air and 12% O2. Data were obtained at 50, 75, 90, and 100% of quadriceps maximal O2 consumption at each fraction of inspired O2. Mb saturation was significantly lower in hypoxia than in normoxia [40 ± 3 vs. 49 ± 3% (SE)] throughout incremental exercise to maximal work rate. With the assumption of a[Formula: see text] at which 50% of Mb-binding sites are bound with O2 of 3.2 Torr, Mb-associated [Formula: see text] averaged 3.1 ± 0.3 and 2.3 ± 0.2 Torr in normoxia and hypoxia, respectively. Net blood lactate efflux was unrelated to intracellular[Formula: see text] across the range of incremental exercise to maximum ( r = 0.03 and 0.07 in normoxia and hypoxia, respectively) but linearly related to O2 consumption ( r = 0.97 and 0.99 in normoxia and hypoxia, respectively) with a greater slope in 12% O2. Net lactate efflux was also linearly related to intracellular pH ( r = 0.94 and 0.98 in normoxia and hypoxia, respectively). These data suggest that with increasing work rate, at a given fraction of inspired O2, lactate efflux is unrelated to muscle cytoplasmic [Formula: see text], yet the efflux is higher in hypoxia. Catecholamine values from comparable studies are included and indicate that lactate efflux in hypoxia may be due to systemic rather than intracellular hypoxia.

scholarly journals Liver ultrasound elastography for the evaluation of periportal fibrosis in schistosomiasis mansoni: A cross-sectional study

2018 ◽  
Author(s):  
Joelma Carvalho Santos ◽  
Andrea Dória Batista ◽  
Carla Maria Mola Vasconcelos ◽  
Roberto Souza Lemos ◽  
Valter Romão de Souza ◽  
...  
Keyword(s):  
Shear Wave ◽  
Shear Wave Elastography ◽  
Cross Sectional Study ◽  
Cutoff Point ◽  
Sectional Study ◽  
Cross Sectional ◽  
Predictive Values ◽  
Cutoff Value ◽  
Periportal Fibrosis ◽  
Schistosomiasis Mansoni

AbstractBackgroundARFI elastrography has been used as a noninvasive method to assess the severity of liver fibrosis in viral hepatitis, although with few studies in schistosomiasis mansoni. We aimed to evaluate the performance of point shear wave elastography (pSWE) for predicting significant periportal fibrosis (PPF) in schistosomotic patients and to determine its best cutoff point.Methodology/Principal findingsThis cross-sectional study included 358 adult schistosomotic patients subjected to US and pSWE on the right lobe. Two hundred two patients (62.0%) were women, with a median age of 54 (ranging 18-92) years. The pSWE measurements were compared to the US patterns of PPF, as gold standard, according to the Niamey classification. The performance of pSWE was calculated as the area under the ROC curve (AUC). Patients were further classified into two groups: 86 patients with mild PPF and 272 patients with significant PPF. The median pSWE of the significant fibrosis group was higher (1.40 m/s) than that of mild fibrosis group (1.14 m/s, p<0.001). AUC was 0.719 with ≤1.11 m/s as the best cutoff value for excluding significant PPF. Sensitivity and negative predictive values were 80.5% and 40.5%, respectively. Whereas, for confirming significant PPF, the best cutoff value was >1.39 m/s, with specificity of 86.1% and positive predictive value of 92.0%.Conclusions/SignificancepSWE was able to differentiate significant from mild PPF, with better performance to predict significant PPF.Author summaryIn the developing world, over 207 million people are infected with parasitic Schistosoma worms. Among the species of Schistosoma that infect humans Schistosoma mansoni is one of the most common causes of illness. Here, we investigated the performance of point shear wave elastography (pSWE) for predicting significant periportal fibrosis (PPF) in schistosomotic patients and to determine its best cutoff point. We examined 358 people from northeast of Brazil for Schistosoma infections. The present study showed that pSWE was able to differentiate significant from mild PPF, with better performance to predict significant PPF.

scholarly journals Sporting myths: the REAL role of lactate during exercise

2016 ◽  
Vol 19 (5) ◽  
Author(s):  
T Mann
Keyword(s):  
Lactate Concentration ◽  
Lactate Production ◽  
Blood Lactate Concentration ◽  
Endurance Performance ◽  
Post Exercise ◽  
Early Exercise ◽  
Important Intermediate ◽  
Lactate Formation ◽  
Exercise Muscle

Background. Lactate or, as it was customarily known, ‘lactic acid’ was one of the first molecules to attract the attention of early exercise scientists, mainly because blood lactate concentration could be measured and was shown to increase with increasing exercise intensity. This connection resulted in lactate being associated with numerous other events associated with high-intensity exercise including muscle cramps, fatigue, acidosis and post-exercise muscle soreness. Nobel prize-winning research by AV Hill and Otto Meyerhof provided a rational explanation linking lactate to anaerobiosis and acidosis, which resulted in this relationship being widely accepted as fact. It was only following isotopic tracer studies of George Brooks and others that the true role of lactate during rest and exercise was revealed. Conclusions. Lactate is now acknowledged as an important intermediate of carbohydrate metabolism, taken up from the blood by tissues such as skeletal and cardiac muscle as a substrate for oxidation. Furthermore, lactate formation consumes a proton, thereby buffering against muscle acidosis. For this reason, lactate production forms an essential aid to endurance performance rather than a hindrance.

scholarly journals The Regulation of Haemocyanin Oxygen Affinity During Emersion of the Crayfish Austropotamobius Pallipes: III. The Dependence of Ca2+-Haemocyanin Binding on the Concentration Of L-Lactate

1987 ◽  
Vol 133 (1) ◽  
pp. 339-352
Author(s):  
S. MORRIS ◽  
C.R. BRIDGES ◽  
M. K. GRIESHABER
Keyword(s):  
Biological Sciences ◽  
Binding Sites ◽  
Lactate Concentration ◽  
Oxygen Affinity ◽  
Calcium Lactate ◽  
Worst Case ◽  
Austropotamobius Pallipes ◽  
University Of Calgary ◽  
Lactate Formation ◽  
The Relationship

The binding of Ca2+ to the haemocyanin of the crayfish Austropotamobius pallipes was investigated. The amount of bound Ca2+ was determined using an ultrafiltration technique to produce haemocyanin-free solutions, the Ca2+ concentration of which could then be compared with that of the original, unfiltered solution. Any difference between the two values would indicate the amount of calcium bound by haemocyanin. The effect of L-lactate on Ca2+ binding was investigated by determining the amount of bound ion at different concentrations of L-lactate. In addition, oxygen equilibrium curves were constructed for some of the solutions to verify that the haemocyanin oxygen affinity remained sensitive to L-lactate and to determine whether the haemocyanin was functionally similar to that used in previous investigations. With 17 mmol 1−1 total Ca2+ and approximately 1 mmol 1−1 L-lactate the number of Ca2+ binding sites was estimated to be between eight and nine per haemocyanin molecule. Without taking into account the formation of calcium lactate, the observed dependency of Ca2+-haemocyanin binding on L-lactate concentration could best be described by the equation: Ca2+/Hc = 8.64-0.32[lactate−]. A ‘worst case’ estimate for maximum calcium lactate formation, assuming Ca2+ to be the only counterion available to lactate, altered the relationship slightly to: Ca2+/Hc = 8.65-0.35[lactate−]. Note: Present address: Department of Biological Sciences, University of Calgary, 2500 University Drive N/V, Calgary, Alberta, Canada T2N 1N4.

scholarly journals Inter-observer agreement on the evaluation of automated breast volume scanner for breast masses

2022 ◽  
pp. 1-11
Author(s):  
Yingchun Liu ◽  
Lin Chen ◽  
Jia Zhan ◽  
Xuehong Diao ◽  
Yun Pang ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Observer Agreement ◽  
Breast Volume ◽  
Imaging Data ◽  
Predictive Values ◽  
Breast Masses ◽  
Cutoff Value ◽  
Automated Breast Volume Scanner ◽  
The Masses ◽  
Sensitivity Specificity

Objective: To explore inter-observer agreement on the evaluation of automated breast volume scanner (ABVS) for breast masses. Methods: A total of 846 breast masses in 630 patients underwent ABVS examinations. The imaging data were independently interpreted by senior and junior radiologists regarding the mass size ([Formula: see text][Formula: see text]cm, [Formula: see text][Formula: see text]cm and total). We assessed inter-observer agreement of BI-RADS lexicons, unique descriptors of ABVS coronal planes. Using BI-RADS 3 or 4a as a cutoff value, the diagnostic performances for 331 masses with pathological results in 253 patients were assessed. Results: The overall agreements were substantial for BI-RADS lexicons ([Formula: see text]–0.779) and the characteristics on the coronal plane of ABVS ([Formula: see text]), except for associated features ([Formula: see text]). However, the overall agreement was moderate for orientation ([Formula: see text]) for the masses [Formula: see text][Formula: see text]cm. The agreements were substantial to be perfect for categories 2, 3, 4, 5 and overall ([Formula: see text]–0.918). However, the agreements were moderate to substantial for categories 4a ([Formula: see text]), 4b ([Formula: see text]), and 4c ([Formula: see text]), except for category 4b of the masses [Formula: see text][Formula: see text]cm ([Formula: see text]). Moreover, for radiologists 1 and 2, there were no significant differences in sensitivity, specificity, accuracy, positive and negative predictive values with BI-RADS 3 or 4a as a cutoff value ([Formula: see text] for all). Conclusion: ABVS is a reliable imaging modality for the assessment of breast masses with good inter-observer agreement.

scholarly journals Initiatives Management's Role in Improving Work Efficiency: A Field Study On Workers in Salalah Methanol Company in Dhofar Governorate

2021 ◽  
Vol 32 (3) ◽  
pp. 24-42
Author(s):  
Abubakar Ahmed Mohammed Almuallam ◽  
Mohammed Nashief S. Disomimba
Keyword(s):  
Analytical Approach ◽  
Pearson Correlation ◽  
Descriptive Analysis ◽  
Demographic Variables ◽  
Work Efficiency ◽  
Sultanate Of Oman ◽  
Scheffe Test ◽  
Study Population ◽  
Level Of Significance

This quantitative study discussed the role of initiatives management in improving the work efficiency of the employees of the Methanol Company in the Dhofar Governorate in the Sultanate of Oman. The problem emerged that some Omani institutions suffered from administrative and economic crises as a result of fluctuations in oil prices, the absence of scientific bases adopted in the selection and appointment of people to jobs, and the absence of criteria for evaluating achievement and results. Therefore, the study aimed to; Diagnosing the level of initiatives management at the Methanol Company in the Dhofar Governorate, and the level of improving the company's work efficiency The study adopted the descriptive analytical approach, and the study population consisted of all employees of the Salalah Methanol Company in the Governorate of Dhofar, who numbered (160) employees. A random sample of (113) employees was selected according to the table of Gresty and Morgan (1970). The researcher designed a questionnaire by making use of the theoretical literature. It consisted of (48) phrases distributed in (8) axes. The following statistical methods were adopted: descriptive analysis, Pearson correlation coefficient, alpha consistency coefficient, T-test for two independent samples, one-way analysis of variance, multiple regression analysis, Scheffe test for dimensional comparisons. The research found a set of results, including: There is a direct relationship between initiatives management and improving work efficiency. There is a statistically significant effect at the level of significance (a ≤ 0.05) between managing initiatives and improving work efficiency. There were no statistically significant differences at the level of significance (a ≤ 0.05) about managing initiatives and improving work efficiency due to demographic variables.

Evaluation of depression and anxiety, and their relationship with insomnia, nightmare and demographic variables in medical students

2017 ◽  
Vol 41 (S1) ◽  
pp. s853-s853
Author(s):  
S.A. Haji Seyed Javadi
Keyword(s):  
Medical Students ◽  
Family Income ◽  
Human Life ◽  
Sleep Onset ◽  
Demographic Variables ◽  
Depression And Anxiety ◽  
Close Relationship ◽  
Study Population ◽  
Competing Interest ◽  
Age Range

IntroductionResearches showed comorbidity of sleep disorders and mental disorders.Objectives and aimsThe current study aimed to evaluate depression and anxiety and their relationship with insomnia, nightmare and demographic variables in the medical students of Qazvin University of Medical Sciences in 2015.MethodThe study population included 253 medical students with the age range of 18–35 years. Data were gathered using Beck depression inventory, Kettle anxiety, and insomnia and nightmare questionnaires and were analyzed by proper statistical methods.ResultsAmong the participants, 126 (49.6%) subjects had depression and 108 (42.5%) anxiety. The prevalence of depression and anxiety among the subjects with lower family income was significantly higher (Chi2 = 6.75, P = 0.03 for depression and Х2 = 27.99, P < 0.05 for anxiety). There was a close relationship between depression with sleep-onset difficulty, difficulty in awakening and daily sleep attacks, and also between anxiety with sleep-onset difficulty and daily tiredness (P < 0.05). In addition, there was a close relationship between depression and anxiety with nightmare; 16.2% of the subjects with depression and 26.5% of the ones with anxiety experienced nightmares.ConclusionResults showed a relationship between nightmare, insomnia and level of family income with increasing depression and anxiety in the medical students; hence, due to the importance of medicine in human life, it is necessary to evaluate the mental health of medical students, identify and solve the relative problems such as anxiety, depression and related symptoms such as insomnia and nightmare in them.Disclosure of interestThe author has not supplied his/her declaration of competing interest.

The Role of Organizational Culture in the Implementation of E-Administration: A Field Study at Banks in Hodeidah

2021 ◽  
Vol 26 (3) ◽  
pp. 57-88
Author(s):  
Maged Abdul Wakil Fadhl Al-Qubati ◽  
Dr. Ali Saleh Ali Al Ajam
Keyword(s):  
Organizational Culture ◽  
Positive Impact ◽  
Modern Technology ◽  
Demographic Variables ◽  
Four Dimensions ◽  
Staff Members ◽  
Study Population ◽  
Organizational Beliefs ◽  
Organizational Expectations

The study aimed to identify the organizational culture practice and its impact on the application of e-administration in the banks operating in Hodeidah. The study used the descriptive analytical method. Since the study population consisted of only (146) administrative staff members, (126) members were selected by the complete census method to whom the questionnaire was distributed to collect relevant data. Major findings showed various degrees in the level of organizational culture and e-administration in favor of the independent variable (organizational culture). Findings also showed statistically significant positive impact of organizational culture represented by its four dimensions (organizational norms, organizational expectations, organizational values, and organizational beliefs) on the application of e-administration. Furthermore, it was found that there were no statistically significant differences of the mean scores among sample's responses on the level of application of e-administration attributed to their demographic variables. However, there were statistically significant differences in the level of organizational culture attributed to gender and courses of computer skills, but there were no differences in other demographic variables. The study recommends that organizational culture in banks regulations should be promoted in order to help them introduce modern technology (e-administration) in all their activities.

scholarly journals Sarcopenia for predicting falls and hospitalization in community-dwelling older adults: EWGSOP versus EWGSOP2

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ming Yang ◽  
Ying Liu ◽  
Yun Zuo ◽  
Huairong Tang
Keyword(s):  
Older Adults ◽  
Community Dwelling ◽  
Predictive Values ◽  
Specific Distribution ◽  
European Working ◽  
Study Population ◽  
Incidence Of Hospitalization ◽  
Community Dwelling Older Adults ◽  
Gender Specific

AbstractThe European Working Group on Sarcopenia in Older People (EWGSOP) recently published an updated version (EWGSOP2). We aimed to compare the predictive values of EWGSOP-defined and EWGSOP2-defined sarcopenia for the incidence of falls and hospitalization in older adults. We defined sarcopenia according to the EWGSOP and the EWGSOP2. We further modified the cut-off points of the EWGSOP and EWGSOP2 according to the lowest quintile values of the gender-specific distribution of our study population, named “modified EWGSOP” and “modified EWGSOP2”, respectively. We included 384 participants. During the follow-up, 98 participants (26.5%) and 51 participants (13.8%) had at least one fall or hospitalization, respectively. EWGSOP2-defined sarcopenia (hazard ratio [HR] 1.86, 95% confidence interval [CI] 1.22–1.84) and modified EWGSOP2-defined sarcopenia (HR 2.09, 95% CI 1.23–3.55) were significantly associated with an increased incidence of falls, respectively. EWGSOP-defined sarcopenia and modified EWGSOP-defined sarcopenia also have a trend to be associated with the incidence of falls, but the results were not statistically significant. Only modified EWGSOP2-defined sarcopenia (HR 2.07, 95% CI 1.01–4.27) was significantly related to an increased incidence of hospitalization. In conclusion, EWGSOP2-defined sarcopenia performed more sensitive than EWGSOP-defined sarcopenia for predicting the incidence of falls or hospitalization, especially when using the modified cutoffs.

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