In Vitro Effects of the Platelet Glycoprotein IIb/IIIa Receptor Antagonist c7E3 Fab on the Activated Clotting Time

Circulation ◽  
1997 ◽  
Vol 95 (3) ◽  
pp. 614-617 ◽  
Author(s):  
Tameshwar Ammar ◽  
Lesley E. Scudder ◽  
Barry S. Coller
Keyword(s):  
Receptor Antagonist ◽  
Platelet Glycoprotein ◽  
Clotting Time ◽  
Activated Clotting Time ◽  
In Vitro Effects

scholarly journals In vitro effects of aprotinin on activated clotting time measured with different activators

1992 ◽  
Vol 104 (4) ◽  
pp. 1135-1140 ◽  
Author(s):  
Jian-Sheng Wang ◽  
Chung-Yuan Lin ◽  
Wei-Te Hung ◽  
Ronald A. Thisted ◽  
Robert B. Karp
Keyword(s):  
Clotting Time ◽  
Activated Clotting Time ◽  
In Vitro Effects

Factors associated with errors in the heparin dose response test: recommendations to improve individualized heparin management in cardiopulmonary bypass

Perfusion ◽  
2020 ◽  
pp. 026765912095297
Author(s):  
Min-Ho Lee ◽  
William Riley
Keyword(s):  
Cardiopulmonary Bypass ◽  
Dose Response ◽  
Clotting Time ◽  
Critical Aspect ◽  
Heparin Dose ◽  
Factors Associated ◽  
Heparin Concentration ◽  
Activated Clotting Time

Background: A critical aspect of cardiopulmonary bypass (CPB) is to achieve full anticoagulation to prevent thrombosis and consumptive coagulation without using excessive amount of heparin. This can be achieved with heparin dose response (HDR) test in vitro to calculate an individualized heparin bolus to reach a target activated clotting time (ACT) and heparin concentration. However, we often observe that the measured ACT (mACT) with the calculated heparin bolus gives significant errors, both positive (mACT is higher than expected) and negative (mACT is lower), from expected ACT (eACT). Methods: We performed a retrospective study of 250 patients who underwent cardiac surgery to attain an error distribution of the mACT from eACT with calculated heparin bolus. In addition, it is aimed to identify possible patterns of baseline ACT (bACT), calculated heparin concentration (CHC) and HDR slope that are associated with the significant positive and negative errors. Results: We found that individualized heparin bolus by HDR test is consistently underestimated while it gave a significant number of positive and negative errors. Further analysis indicates that significant negative errors correlate with high bACT and slope and low CHC while significant positive errors with low bACT and slope and high CHC. Conclusion: The mACT can be substantially different from eACT. The accuracy of the HDR test appears to be dependent upon bACT, slope, and CHC. Based on our analysis, we provide several recommendations and a flow chart to improve the quality of individualized heparin management on CPB.

Reliability of the Heparin Management Test for Monitoring High Levels of Unfractionated Heparin

2000 ◽  
Vol 92 (6) ◽  
pp. 1594-1602 ◽  
Author(s):  
Fritz Mertzlufft ◽  
Andreas Koster ◽  
Roland Hansen ◽  
Anne Risch ◽  
Herrmann Kuppe ◽  
...  
Keyword(s):  
Cardiopulmonary Bypass ◽  
Storage Time ◽  
Coagulation Factors ◽  
Clotting Time ◽  
Activated Clotting Time ◽  
Group I ◽  
Group Ii ◽  
And Storage

Background The authors assessed the heparin management test in vitro in volunteers and in vivo during cardiopulmonary bypass. Methods In vitro, the heparin management test was analyzed for heparin levels between 0 and 6 IU/ml using variations in hematocrit, platelets, procoagulants, and storage time. The in vivostudies consisted of two groups: In group I (cardiopulmonary bypass </= 90 min, n = 40), anticoagulation was performed according to the activated clotting time (with or without aprotinin); in group II (cardiopulmonary bypass >/= 180 min, with aprotinin) included use (n = 10) and nonuse of coumadin (n = 10) and anticoagulation according to the automated heparin dose-response assay. Tests were performed in duplicate (whole blood, two heparin management test analyzers) and compared with anti-Xa activity (plasma). Results In vitro, the results of the heparin management test (n = 1,070) correlated well with heparin concentration (r2 = 0.98). Dilution and storage time did not affect the heparin management test; a hematocrit of 60% and reduced procoagulants (10%) prolonged clotting time. In vivo, the correlation (heparin management test vs. anti-Xa) was strong in group I (r2 = 0.97 [with aprotinin] and 0.96 [without aprotinin]; n = 960) and group II without coumadin (r2 = 0.89, n = 516). In group II with coumadin, the overall correlation was r2 = 0.87 and 0.79 (n = 484), although the range varied widely (0.57-0.94, between-analyzer differences 0-47%). Conclusions The results of the heparin management test were influenced by hematocrit, plasma coagulation factors, and the heparin level, but not by use of aprotinin. The heparin management test provided reliable values in vitro in group I, and in group II without coumadin but was less reliable in group II with coumadin.

Monitoring Activated Clotting Time for Combined Heparin and Aprotinin Application: An In Vitro Evaluation of a New Aprotinin-Insensitive Test Using SONOCLOT

2005 ◽  
Vol 101 (2) ◽  
pp. 308-314 ◽  
Author(s):  
Michael T. Ganter ◽  
Seraina Dalbert ◽  
Kirk Graves ◽  
Richard Klaghofer ◽  
Andreas Zollinger ◽  
...  
Keyword(s):  
Clotting Time ◽  
In Vitro Evaluation ◽  
Activated Clotting Time

An in vitro method for comparing biocompatibility of materials for extracorporeal circulation

Perfusion ◽  
2002 ◽  
Vol 17 (2) ◽  
pp. 125-132 ◽  
Author(s):  
Giles J Peek ◽  
Richard Scott ◽  
Hilliary M Killer ◽  
Richard K Firmin
Keyword(s):  
International Normalized Ratio ◽  
The Other ◽  
Clotting Time ◽  
Roller Pump ◽  
In Vitro Method ◽  
Cell Counts ◽  
Activated Clotting Time ◽  
Free Haemoglobin ◽  
Group 2

We measured the response of fresh heparinized human blood to recirculation through circuits made of LVA (Portex Industries, Hythe, Kent, UK), SRT (Rehau UK, Langley, Slough, UK) and Tygon® S-65-HL (Norton Performance Plastics, Corby, Northants, UK), as control. Circuit construction: 1/2 in. tubing, heat exchanger (Dideco D-720P), Stockert roller pump, just underoccluded, Cincinnati Sub Zero heater, circuit volume of 500 ml. Flow 3.45 l/min, 37°C. Samples: at 10 min, 1, 2, 4 and 6 h. n= 5 in each group; 2/5 SRT experiments were stopped at 45 and 60 min due to overpressurization. Results: Baseline activated clotting time (ACT) of 300 s, increasing in all groups as fibrinogen fell to zero with SRT and LVA. Minimum fibrinogen was 1 g/l for Tygon. Absolute thrombocytopenia occurred (SRT and LVA 60 min and Tygon 240 min). International normalized ratio (INR) in both the SRT and LVA circuits increased, but mean increase for Tygon (0.56) was smaller than the other two materials. Plasma free haemoglobin increased in all three materials; the increase was greater in the LVA circuits compared to the control. C5b9 levels increased equally in all groups. Lactoferrin levels rose equally in all groups to a maximum at 150 min. The neutrophil counts fell, mirroring the lactoferrin. The total white cell counts also fell in all groups; in the LVA circuits, the fall was significantly lower than in the control. Rapid disappearance of platelets and fibrinogen from the blood in the SRT and LVA circuits excludes them both from extracorporeal use. Paradoxically, SRT caused the least complement activation of the three materials. This method can be used to compare biocompatibility.

In vitro and in vivo effects of hemodilution on kaolin-based activated clotting time predicted heparin requirement using a heparin dose–response technique

2016 ◽  
Vol 30 (6) ◽  
pp. 923-928 ◽  
Author(s):  
Junko Ichikawa ◽  
Satoshi Hagihira ◽  
Testu Mori ◽  
Mitsuharu Kodaka ◽  
Keiko Nishiyama ◽  
...  
Keyword(s):  
Dose Response ◽  
Clotting Time ◽  
Heparin Dose ◽  
Activated Clotting Time ◽  
In Vivo Effects

Experimental study on the hemostatic effect of cyanoacrylate intended for catheter securement

2018 ◽  
Vol 20 (1) ◽  
pp. 79-86 ◽  
Author(s):  
Sheng Zhang ◽  
Amanda R Guido ◽  
Richard G Jones ◽  
Benjamin J Curry ◽  
Angela S Burke ◽  
...  
Keyword(s):  
Whole Blood ◽  
Blood Platelet ◽  
Clotting Time ◽  
Intravenous Catheter ◽  
Hemostatic Effect ◽  
Activated Clotting Time ◽  
In Vivo Testing ◽  
Bleeding Score

Purpose: The use of cyanoacrylate for intravenous catheter securement is of interest to clinicians and patients, because of the superior adhesive strength and hemostatic effect of cyanoacrylate compared to current securement devices. The purpose of this study is to use novel in vitro and in vivo testing methods to analyze the hemostatic effect of a catheter securement cyanoacrylate (cyanoacrylate). Methods: An unprecedented in vitro method was performed to determine the effects of a cyanoacrylate on a customized modified activated clotting time assay and blood flow inhibition assay by exposing blood or plasma to either one or three drops of cyanoacrylate. For the in vivo testing, full-thickness incisions were made on swine, and the bleeding was scored prior to treatment and at 3, 6, 9, and 12 min after treatment. Results: The cyanoacrylate rapidly achieved hemostasis in the presence of anticoagulated whole blood, platelet-poor plasma, and non-anticoagulated whole blood, in vitro. The cyanoacrylate achieved hemostasis 12-fold faster than thromboplastin in the modified activated clotting time assay. The cyanoacrylate does not alter normal blood clotting, as measured by prothrombin time. In vivo, the bleeding score of cyanoacrylate prior to treatment and at 3, 6, 9, and 12 min after treatment were 2.3 ± 1.0, 0.3 ± 0.5, 0.2 ± 0.5, 0.2 ± 0.4, and 0.2 ± 0.4, respectively. Conclusion: This study indicates that cyanoacrylate demonstrates a potent mechanical hemostatic effect and cyanoacrylate in the presence of anticoagulated whole blood has an activated clotting time that is 12 times quicker than thromboplastin. The cyanoacrylate was found to be significantly equivalent to two known hemostatic agents, in vivo.

Radioiodinated Human Fibrinogen. In Vitro Effects of Increasing Iodination

1975 ◽  
Author(s):  
B. E. Ly ◽  
P. Kierulf
Keyword(s):  
Amino Acid ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Clotting Time ◽  
Terminal Amino Acid ◽  
Human Fibrinogen ◽  
Terminal Amino ◽  
In Vitro Effects ◽  
Polypeptide Chains

Fibrinogen preparations with increasing contents of iodine, ranging from 0.2 to 20 atoms of iodine per molecule fibrinogen, were obtained with the ICl method. Aggregation and shortening of the thrombin clotting time occurred when the content of iodine exceeded 3 atoms per molecule.Upon the action of thrombin, the increase in N-terminal glycine, reflecting fibrin formation, was almost identical in native and iodinated fibrinogen. At visible gelation, however, decreased amounts of N-terminal glycine were found in heavily iodinated fibrinogen, thus indicating enhanced fibrin polymerization. N-terminal analysis of heavily iodinated fibrinogen demonstrated a deficiency in N-terminal tyrosine concomitantly with the apparance of a new N-terminal amino acid, identified as mono-iodo-tyrosine.Polyacrylamide gel electrophoresis at pH 8.9 revealed an increase in mobility following extensive iodination, but no shift in the isoelectric point was observed upon isofocusing.Neither clottability nor the behaviour of fibrinogen and its subunit polypeptide chains on SDS-gel electrophoresis was affected by iodination.

Sign in / Sign up

Export Citation Format

Share Document