Comparison of viscoelastic test results from blood collected near simultaneously from the jugular and saphenous veins in cats

2020 ◽  
pp. 1098612X2095961
Author(s):  
James Mack Fudge ◽  
Katherine S Cano ◽  
Bernie Page ◽  
Unity Jeffery

Objectives The aim of this study was to compare viscoelastic test results from samples collected from a jugular vein using a 20 G needle and a medial saphenous vein using a 22 G needle in cats presenting for elective ovariohysterectomy (OHE) or castration. Methods Forty apparently healthy cats (20 males and 20 females) presenting for elective OHE or castration were included in a prospective study observing viscoelastic test results from central and peripherally collected whole blood. Cats were anesthetized during blood collection with a standardized protocol including buprenorphine, ketamine, dexmedetomidine and isoflurane. Blood samples from jugular and saphenous veins were collected near simultaneously. Viscoelastic evaluations of whole blood were performed using a point-of-care device measuring clot time (CT), clot formation time (CFT), alpha angle (α), maximum clot formation (MCF), and amplitude at 10 and 20 mins (A10 and A20, respectively). Viscoelastometry continued post-clot time to determine a lysis index at 30 and 45 mins (LI30 and LI45, respectively) to assess fibrinolysis. Results Studied cats had a median age of 18 months (range 5 months to 5 years) and a median weight of 3.6 kg (range 2.7–5.9 kg). A total of 80 samples were available for analysis. While lysis indices were not different, viscoelastic measures of coagulation differed between sampling sites (CT, P <0.005; CFT, P = 0.01; α, P <0.05; MCF, P <0.0005; A10, P <0.0005; A20, P <0.0005). Conclusions and relevance Viscoelastic results from jugular venous blood samples appear to be more hypercoagulable than those collected from the medial saphenous vein, suggesting that the same site should be used consistently for serial monitoring or for collecting study data.

2019 ◽  
Vol 14 (5) ◽  
pp. 883-889
Author(s):  
William D. Arnold ◽  
Kenneth Kupfer ◽  
Randie R. Little ◽  
Meera Amar ◽  
Barry Horowitz ◽  
...  

Background: Point-of-care (POC) hemoglobin A1c (HbA1c) testing has advantages over laboratory testing, but some questions have remained regarding the accuracy and precision of these methods. The accuracy and the precision of the POC Afinion™ HbA1c Dx test were investigated. Methods: Samples spanning the assay range were collected from prospectively enrolled subjects at three clinical sites. The accuracy of the POC test using fingerstick and venous whole blood samples was estimated via correlation and bias with respect to values obtained by an NGSP secondary reference laboratory (SRL). The precision of the POC test using fingerstick samples was estimated from duplicate results by calculating the coefficient of variation (CV) and standard deviation (SD), and separated into its components using analysis of variance (ANOVA). The precision of the POC test using venous blood was evaluated from samples run in four replicates on each of three test cartridge lots, twice per day for 10 consecutive days. The SD and CV by study site and overall were calculated. Results: Across the assay range, POC test results from fingerstick and venous whole blood samples were highly correlated with results from the NGSP SRL ( r = .99). The mean bias was −0.021% HbA1c (−0.346% relative) using fingerstick samples and −0.005% HbA1c (−0.093% relative) using venous samples. Imprecision ranged from 0.62% to 1.93% CV for fingerstick samples and 1.11% to 1.69% CV for venous samples. Conclusions: The results indicate that the POC test evaluated here is accurate and precise using both fingerstick and venous whole blood.


2018 ◽  
Vol 88 (3-4) ◽  
pp. 151-157 ◽  
Author(s):  
Scott W. Leonard ◽  
Gerd Bobe ◽  
Maret G. Traber

Abstract. To determine optimal conditions for blood collection during clinical trials, where sample handling logistics might preclude prompt separation of erythrocytes from plasma, healthy subjects (n=8, 6 M/2F) were recruited and non-fasting blood samples were collected into tubes containing different anticoagulants (ethylenediaminetetra-acetic acid (EDTA), Li-heparin or Na-heparin). We hypothesized that heparin, but not EDTA, would effectively protect plasma tocopherols, ascorbic acid, and vitamin E catabolites (α- and γ-CEHC) from oxidative damage. To test this hypothesis, one set of tubes was processed immediately and plasma samples were stored at −80°C, while the other set was stored at 4°C and processed the following morning (~30 hours) and analyzed, or the samples were analyzed after 6 months of storage. Plasma ascorbic acid, as measured using HPLC with electrochemical detection (LC-ECD) decreased by 75% with overnight storage using EDTA as an anticoagulant, but was unchanged when heparin was used. Neither time prior to processing, nor anticoagulant, had any significant effects upon plasma α- or γ-tocopherols or α- or γ-CEHC concentrations. α- and γ-tocopherol concentrations remained unchanged after 6 months of storage at −80°C, when measured using either LC-ECD or LC/mass spectrometry. Thus, refrigeration of whole blood at 4°C overnight does not change plasma α- or γ-tocopherol concentrations or their catabolites. Ascorbic acid is unstable in whole blood when EDTA is used as an anticoagulant, but when whole blood is collected with heparin, it can be stored overnight and subsequently processed.


Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
Joancy M Archeval-Lao ◽  
Hope Moser ◽  
Stephen A Riney ◽  
Jorge Kawano-Castillo ◽  
Stephanie A Parker ◽  
...  

Background: Currently, t-PA is the only FDA approved treatment for acute ischemic stroke (AIS). Supplementing t-PA with therapeutic hypothermia is being evaluated, but cooler temperatures may affect the enzymatic activity of t-PA. Thromboelastography (TEG) determines coagulation status in whole blood, and has detected hypercoagulability in AIS patients compared to healthy controls. Using TEG, we evaluated the effect of variable degrees of hypothermia on clot formation and lysis in AIS patients receiving t-PA. Methods: Between June 2012 -July 2013, venous blood from 18 AIS patients receiving t-PA within 4.5 hours of symptom onset was collected prior to and 10 minutes after t-PA bolus. Blood samples were analyzed by TEG at 30°C, 33°C, and 37°C. The variables of interest were R (initiation of clot formation), K (speed of clot strengthening), Angle α (rate of clot formation), and LY30 (percentage of clot lysis over 30 minutes) (see figure). All statistical analyses were performed using SAS 9.3. Results: Baseline R averaged 6.0, 5.6, and 4.6 minutes at 30°C, 33°C, and 37°C (p=0.02),K averaged 2.5, 2.3, and 1.4 (p=0.01),and Angle averaged 59.1, 62.4, and 69.3(p=0.01), indicating slower clotting at lower temperatures. Post t-PA LY30 averaged 93.9, 93.9, 89.8 (p= 0.61, N=18) indicating no effect on t-PA lytic activity at lower temperatures. Conclusions: Our data suggest that hypothermia progressively slows clot formation in AIS patients but has no effect on the lytic effect of t-PA as measured by TEG.


2001 ◽  
Vol 39 (5) ◽  
pp. 1788-1790 ◽  
Author(s):  
H. H. Kessler ◽  
E. Stelzl ◽  
R. B. Raggam ◽  
J. Haas ◽  
F. Kirchmeir ◽  
...  

Author(s):  
Margaret A Black ◽  
Guomiao Shen ◽  
Xiaojun Feng ◽  
Wilfredo Garcia Beltran ◽  
Yang Feng ◽  
...  

Objectives: Numerous serologic immunoassays have been launched to detect antibodies to SARS-CoV-2, including rapid tests. Here, we validate use of a lateral flow immunoassay (LFI) intended for rapid screening and qualitative detection of anti-SARS-CoV-2 IgM and IgG in serum, plasma, and whole blood, and compare results with ELISA. We also seek to establish the value of LFI testing on blood obtained from a capillary blood sample. Methods: Samples collected by venous blood draw and capillary finger stick were obtained from patients with SARS-CoV-2 detected by RT-qPCR and control patients negative for SARS-CoV-2. Samples were tested with the 2019-nCoV IgG/IgM Detection Kit (Colloidal Gold) lateral flow immunoassay, and antibody calls were compared with results obtained by ELISA. Results: The Biolidics LFI kit shows clinical sensitivity of 92% at 7 days after PCR diagnosis of SARS-CoV-2 on venous blood. Test specificity was 92% for IgM and 100% for IgG. There was no significant difference in detecting IgM and IgG with Biolidics LFI and ELISA at D0 and D7 (p=1.00), except for detection of IgM at D7 (p=0.04). Finger stick whole blood of SARS-CoV-2 patients showed 93% sensitivity for antibody detection. Conclusions: Clinical performance of Biolidics 2019-nCoV IgG/IgM Detection Kit (Colloidal Gold) is comparable to ELISA and showed consistent results across different sample types. Furthermore, we show that capillary blood obtained by finger stick shows similar sensitivity for detecting anti-SARS-CoV-2 IgM and IgG antibodies as venous blood samples. This provides an opportunity for decentralized rapid testing in the community and may allow point-of-care and longitudinal self-testing for the presence of anti-SARS-CoV-2 antibodies.


Blood ◽  
1971 ◽  
Vol 38 (4) ◽  
pp. 422-430 ◽  
Author(s):  
GEOFFREY M. BRITTIN ◽  
SHIRLEY A. DEW ◽  
ELVI K. FEWELL

Abstract We have evaluated the use of an optical particle counter to perform automated platelet counts on whole blood. The erythrocytes were lysed by dilution of whole blood with 2 M urea and the remaining platelets and leukocytes were enumerated by a darkfield microscope optical system that detects light diffracted by them. A suspension of fixed human platelets available commercially was highly satisfactory for standardization. The method gave accurate and reproducible platelet counts, comparable with those of electronic particle counting on venous blood and substantially more reliable platelet counts on thrombocytopenic and finger-puncture blood samples. We believe that errors resulting from the electronic method were caused by technical difficulties of sample handling and not to an intrinsic error in electronic counting. By using the automated optical method we found no significant difference between the platelet counts of capillary and venous blood, although capillary platelet counts had twice the variability of venous counts. The optical technique has important advantages over electronic platelet counting, and its superiority appears to be due to the ability to count platelets in diluted whole blood rather than in plasma. It should prove especially useful in performing the large numbers of platelet counts on thrombocytopenic and finger-puncture blood samples that are increasingly important for management of patients receiving chemotherapy.


2019 ◽  
Vol 14 (5) ◽  
pp. 890-895 ◽  
Author(s):  
William D. Arnold ◽  
Kenneth Kupfer ◽  
Monica Hvidsten Swensen ◽  
Kyle S. Fortner ◽  
Harold E. Bays ◽  
...  

Background: Point-of-care (POC) HbA1c tests hold the promise of reducing the rates of undiagnosed diabetes, provided they exhibit acceptable analytical performance. The precision and total error of the POC (Afinion™ HbA1c Dx) test were investigated using whole blood samples obtained by fingerstick and venipuncture. Methods: Fingerstick samples spanning the assay range were collected from 61 subjects at three representative POC sites. At each site, six fingerstick samples were obtained from each subject and tested on the POC test across two (Afinion AS100) instruments. Repeatability, between-operator, and between-instrument components of variance were calculated using analysis of variance (ANOVA). Four venous samples (low, threshold, medium, and high HbA1c) were measured in duplicate across three instruments using three reagent lots, twice per day over 20-days. Repeatability, between-run, between-day, between-lot, and between-instrument components of variance were calculated. These fingerstick and venous blood results, combined with estimates of imprecision and bias from a prior investigation, allowed for the calculation of the total coefficient of variation (CV) and total error of the POC test using fingerstick and venous whole blood samples. Results: The total imprecision ranged from 1.30% to 2.03% CV using fingerstick samples and from 1.31% to 1.64% CV using venous samples. The total error ranged from 2.87% to 4.75% using fingerstick samples and from 2.93% to 3.80% using venous samples. Conclusions: The POC test evaluated here is precise across its measuring range using both fingerstick and venous whole blood. The calculated total error of the test is well under the accepted quality requirement of ≤6%.


2020 ◽  
Vol 5 (3) ◽  
pp. 516-530
Author(s):  
Michael M Mbughuni ◽  
Maria A Stevens ◽  
Loralie J Langman ◽  
Yogish C Kudva ◽  
William Sanchez ◽  
...  

Abstract Background Immunosuppressant therapeutic drug monitoring (TDM) usually requires outpatient travel to hospitals or phlebotomy sites for venous blood collection; however Mitra® Microsampling Device (MSD) sampling could allow self-collection and shipping of samples to a laboratory for analysis. This study examined the feasibility of using volumetric microsampling by MSD for TDM of tacrolimus (TaC) and cyclosporin A (CsA) in transplant patients, along with their feedback on the process. Methods MSD was used to collect TaC and CsA from venous (VB) or capillary (CB) blood. The MSDs were rehydrated, extracted, and analyzed using on-line solid phase extraction coupled to tandem mass spectrometry (SPE-MS/MS). We report an abbreviated method validation of the MSD including: accuracy, precision, linearity, carry-over, and stability using residual venous whole blood (VB) samples. Subsequent clinical validation compared serially collected MSD + CB against VB (200 µL) from transplant patients. Results Accuracy comparing VB vs. MSD+VB showed high clinical concordance (TaC = 89% and CsA = 98%). Inter- and intra-precision was ≤11.5 %CV for TaC and CsA. Samples were stable for up to 7 days at room temperature with an average difference of &lt;10%. Clinical validation with MSD+CB correlated well with VB for CsA (slope = 0.95, r2 = 0.88, n = 47) and TaC (slope = 0.98, r2 = 0.82, n = 49). CB vs. VB gave concordance of 94% for CsA and 79% for TaC. A satisfaction survey showed 82% of patients preferred having the capillary collection option. Conclusion Transplant patients favored having the ability to collect capillary samples at home for TaC/CsA monitoring. Our results demonstrate good concordance between MSD+CB and VB for TaC and CsA TDM, but additional studies are warranted.


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