Gestational coagulopathy: breakthrough in views on prevention of bleeding

2017 ◽  
pp. 40-46
Author(s):  
M. Makarenko ◽  
◽  
D. Govsieiev ◽  
A. Slobodenyuk ◽  
V. Berestovoy ◽  
...  

Nowadays, for understanding the mechanisms of hemostasis used the «cascade» (the waterfall) model for process of blood clotting. From the end of the 19th century, scientists have been trying to unravel the mechanism of blood clotting, simulate hemostasis. Attempts to assess the system as a whole, as a single functioning complex, led to a method, known as, thromboelastography (TEG). The objective: examine the value of the TEG in prevention of bleeding in pregnant with a low level of platelets. Patients and methods. Аnalysis of pregnant women during the third trimester with a level of platelets below 150*109/l was done. All women tested with TEG method. The main group (MG) consist of 91 woman with changes in the hemostasis system. MG randomly divided into 2 subgroups. In the I subgroup 48 women received infusion of blood components. In the II subgroup 43 women without correction in system of hemostasis. The control group (CG) consist of 44 women with platelet level more than 150*109/l, without pathological changes according to TEG. Results. Comparison of blood loss during childbirth and cesarean section in subgroup I and II, as well as in CG, demonstrates less blood loss I subgroup in comparison with II subgroup (p < 0.05). Smallest blood loss noted in CG compared to the MG (p<0.05). Conclusions. 1. Our research shows the value of the TEG in bleeding prevention in women with low levels of platelets. In general, TEG method shows the overall status of the hemostatic system in vivo. 2.Determination of indicators of the hemostatic system is extremely important, especially in cases where it expected to «mandatory» blood loss during childbirth, surgeries etc. Proper correction hemostatic changes based on TEG data helps to prevent the development of massive bleeding. Key words: thromboelastography, obstetric hemorrhage, thrombocytopenia, hemostasis.

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 496
Author(s):  
Lisa Krautwald ◽  
Ralf Smeets ◽  
Carolin Stolzer ◽  
Rico Rutkowski ◽  
Linna Guo ◽  
...  

The influence of UV light and non-thermal plasma on the osseointegration of yttria-stabilized zirconia implants (Y-TZP) comparing the two methods is unclear. The aim of this study was to show the influence of these methods on the osseointegration of dental zirconia implants in an animal model. A total of 54 implants were either untreated, treated with UV light (UV), or non-thermal oxygen plasma for 12 min and inserted into the parietal bones of six domestic pigs. The animals were sacrificed after a healing interval of two, four, and nine weeks. The degree of osseointegration was determined using histomorphometric determination of bone-to-implant contact values (BIC) and the bone-to-implant contact values within the retentive parts of the implants (BAFO). BIC values decreased in all groups after four weeks of healing and re-increased after nine weeks in all groups. BAFO increased significantly over time in all groups. However, there were no statistically significant differences in BIC and BAFO values between the control group and the test groups and over time. Clinical studies may follow to confirm the influence of cold plasma and UV light on the healing and survival of zirconia implants.


2015 ◽  
Vol 122 (2) ◽  
pp. 387-398 ◽  
Author(s):  
Eva Herzog ◽  
Franz Kaspereit ◽  
Wilfried Krege ◽  
Baerbel Doerr ◽  
Jochen Mueller-Cohrs ◽  
...  

Abstract Background: Edoxaban is an oral, selective direct factor Xa inhibitor approved in Japan for venous thromboembolism prevention after orthopedic surgery. Data are lacking regarding reversal strategies for edoxaban; this study assessed whether four-factor prothrombin complex concentrate (Beriplex®/Kcentra®; CSL Behring GmbH, Marburg, Germany) can effectively reverse its effects on hemostasis using a previously described rabbit model. Methods: The study comprised assessments of thrombin generation in vitro, pharmacokinetic parameters, and edoxaban reversal in vivo. In a blinded in vivo stage, a standardized kidney incision was performed in animals (n = 11 per group) randomized to receive vehicle + saline, edoxaban (1,200 μg/kg) + saline, or edoxaban (1,200 μg/kg) + four-factor prothrombin complex concentrate (50 IU/kg). Animals were monitored for treatment impact on hemostasis and coagulation parameters. Data are median (range). Statistical tests were adjusted for multiple testing. Results: Edoxaban administration increased blood loss (30 [2 to 44] ml) and time to hemostasis (23 [8.5 to 30.0] min) compared with the control group (3 [1 to 8] ml and 3 [2.0 to 5.0] min, respectively). Biomarkers of coagulation (prothrombin time, activated partial thromboplastin time, whole blood clotting time) and thrombin generation parameters (e.g., peak thrombin, endogenous thrombin potential, lag time) were also affected by edoxaban. Administration of four-factor prothrombin complex concentrate significantly reduced time to hemostasis (to 8 [6.5 to 14.0] min, observed P &lt; 0.0001) and total blood loss (to 9 [4 to 22] ml, observed P = 0.0050) compared with the edoxaban + saline group. Of the biomarkers tested, prothrombin time, whole blood clotting time, and endogenous thrombin potential correlated best with clinical parameters. Conclusion: In a rabbit model of hemostasis, four-factor prothrombin complex concentrate administration significantly decreased edoxaban-associated hemorrhage.


2020 ◽  
Vol 11 (1) ◽  
pp. 4-14
Author(s):  
D. S. Soldatova ◽  
A. I. Bezhin ◽  
T. N. Kudryavtseva

Liver surgeries are associated with the risk of bleeding and the development of adhesive disease. Sodium carboxymethylcellulose (Na-CMC) forms an elastic swelling gel and a “lattice” that holds the blood cells.The aim: determine the concentration of Na-CMC, which has the maximum hemostatic and anti-adhesive effect, during liver surgeries in the experiment.Materials and methods. The coagulating effect of Na-CMC (from 0.5% to 9%) was studied in vitro. In vivo experiment on 167 male Wistar rats weighing 185–250 g studied the bleeding time and the amount of blood loss, anti-adhesive activity in the model of liver surgery by cutting off the edge of the organ in the standard way: the depth and width of the wound is 1 cm; the height is 3 mm.Results. In vitro the minimum coagulating effect was obtained in 3% of Na-CMC. In vivo the maximum effect on reducing the bleeding time (–46% compared to the control, p < 0.01) and the amount of blood loss (–27% compared to the control, p < 0.01) had 6% Na-CMC. Then, according to the degree of decrease in the bleeding time, there were: 5% Na-CMC (–40%), 4% Na-CMC (–37%), 3% Na-CMC (–29%), 7% Na-CMC (–27%), 8% Na-CMC (–11%). For the amount of blood loss, a similar pattern of decreasing effect was observed: 5% Na-CMC (–21%), 4% Na-CMC (–14%), 7% Na-CMC (–12%), 3% Na-CMC (–11%), 8% Na-CMC (–5%). When comparing all the studied concentrations of Na-CMC gel with the control group in terms of bleeding time and blood loss, the differences are statistically significant: p < 0.01. Maximum anti-adhesive activity was observed for 6% Na-CMC on days 7 and 14 after surgery: the adhesive process was estimated at 0.497 [0.000–0.497] and 0.962 [0.000–1.301] points vs. 2.457 [2.118–2.457] and 4.071 [3.758–4.602] points in the control group (p < 0.01).Conclusion. The maximum hemostatic and anti-adhesive effect has 6% Na-CMC.


Author(s):  
Konstantin G Gurevich ◽  
Aleksandr L Urakov ◽  
Linara I Bashirova ◽  
Aleksandr V Samorodov ◽  
Peter P Purygin ◽  
...  

Objective: It is known that local or systemic injection of hemostatic drugs is used to reduce blood loss and number of blood transfusions in patients with hypocoagulation and hemorrhagic diathesis. However, the analysis of literature data shows that the drugs applied for the control of bleeding, traditionally used in medical practice, are not effective enough. This study deals with the systemic hemostatic activity of bis (2-aminoethan-1- sulfonate) calcium in the experiment.Methods: Experimental work in vitro is performed on the blood of healthy male donors, under conditions in vivo it is done on intraperitoneal injection in male rats. Thromboelastography was carried out with apparatus Thromboelastography (TEG) 5000 (Haemoscope Corporation, United States). The influence of first synthesized derivative and ethamsylate on functional activity of platelets was studied using a platelet aggregation analyzer “Biola 230LA” (Russia). Experimental evaluation of the system specific hemostatic activity in vivo was carried out using the model of parenchymatous bleeding in mature male rats. The interference came amid registration of bleeding stop time and extent of blood loss.Results: Bis (2-aminoethan-1-sulfonate) calcium shows procoagulation and proaggregant activity both in vitro and in vivo. Proaggregatory effect of bis (2-aminoethan-1-sulfonate) calcium is successfully implemented in the systemic hemostatic activity in terms of parenchymal bleeding, surpassing the control group and the group of etamsylate.Conclusion: The results of these studies reveal potentially high systemic hemostatic activity of bis (2-aminoethan-1-sulfonate) calcium, urging the need for further study on this compound and its analogs to create on their basis highly efficient, selective correctors of the hemostatic system.


Author(s):  
Alexandr A. Kinzersky ◽  
Vladimir T. Dolgikh ◽  
Mikhail S. Korzhuk ◽  
Daria A. Kinzerskaya ◽  
Semyon V. Romanenko

The aim of the study was to determine experimentally the effect of hemodilution by the 2:1 sterofundin/gelofusine (SG) solution on hemostatic parameters in vitro and in vivo.Material and methods. Experiments were carried out on 75 male Wistar rats weighing 270-380 g and anesthetized with intramuscular tiletamine-zolazepam (40 mg/kg) + xylazine (10 mg/kg). Animals were divided randomly into 4 groups: Group 1 - in vitro 25-percent dilution of carotid blood samples by the SG solution (n=12), Group 2 - in vitro 37.5-percent dilution of similar samples (n=11), Group 3 - in vivo 25-percent dilution (n=10), Group 4 - the controls (n=42) with no dilution. The first stage of the study compared the in vitro dilution groups with the control group and with each other; the second stage compared the in vivo dilution group with the control group. The parameters of low-frequency piezoelectric tromboelastography (LFPTEG), clotting tests and complete blood count were studied to evaluate the effect of hemodilution.Results. At a 25-percent hemodilution with 2:1 CG solution in vitro and in vivo, the hemostatic parameters retained within the reference limits, but a trend to increased intensity of the enzymatic reactions of the coagulation cascade and a significant increase in clot polymerization in vitro due to relative anticoagulant deficiency became evident.In vitro 37.5-percent blood dilution significantly reduced the blood level of fibrinogen and platelet count, inhibited the intensity of the proteolytic stage of coagulation, reduced the clot density at the T3 gelation point, at 5 minutes after reaching it and the maximum amplitude (MA) of the LFPTEG curve, as well as significantly reduced anticoagulant activity of the blood. The observed changes in hemostatic parameters were significantly outside the reference limits, which may affect the interpretation of the experimental results and be clinically important. We found negative correlation between clot density and platelet activity at 25-percent dilution in vivo, whereas at 37.5-percent dilution in vitro an additional positive correlations between platelet count and fibrinogen levels were determined.Conclusion. A 25-percent hemodilution with 2:1 CG solution should be considered "safe" for the in vivo hemostatic system providing minimal effect on the in vitro parameters in the experiment.


Author(s):  
Arthur J. Wasserman ◽  
Azam Rizvi ◽  
George Zazanis ◽  
Frederick H. Silver

In cases of peripheral nerve damage the gap between proximal and distal stumps can be closed by suturing the ends together, using a nerve graft, or by nerve tubulization. Suturing allows regeneration but does not prevent formation of painful neuromas which adhere to adjacent tissues. Autografts are not reported to be as good as tubulization and require a second surgical site with additional risks and complications. Tubulization involves implanting a nerve guide tube that will provide a stable environment for axon proliferation while simultaneously preventing formation of fibrous scar tissue. Supplementing tubes with a collagen gel or collagen plus extracellular matrix factors is reported to increase axon proliferation when compared to controls. But there is no information regarding the use of collagen fibers to guide nerve cell migration through a tube. This communication reports ultrastructural observations on rat sciatic nerve regeneration through a silicone nerve stent containing crosslinked collagen fibers.Collagen fibers were prepared as described previously. The fibers were threaded through a silicone tube to form a central plug. One cm segments of sciatic nerve were excised from Sprague Dawley rats. A control group of rats received a silicone tube implant without collagen while an experimental group received the silicone tube containing a collagen fiber plug. At 4 and 6 weeks postoperatively, the implants were removed and fixed in 2.5% glutaraldehyde buffered by 0.1 M cacodylate containing 1.5 mM CaCl2 and balanced by 0.1 M sucrose. The explants were post-fixed in 1% OSO4, block stained in 1% uranyl acetate, dehydrated and embedded in Epon. Axons were counted on montages prepared at a total magnification of 1700x. Montages were viewed through a dissecting microscope. Thin sections were sampled from the proximal, middle and distal regions of regenerating sciatic plugs.


1987 ◽  
Vol 26 (01) ◽  
pp. 1-6 ◽  
Author(s):  
S. Selvaraj ◽  
M. R. Suresh ◽  
G. McLean ◽  
D. Willans ◽  
C. Turner ◽  
...  

The role of glycoconjugates in tumor cell differentiation has been well documented. We have examined the expression of the two anomers of the Thomsen-Friedenreich antigen on the surface of human, canine and murine tumor cell membranes both in vitro and in vivo. This has been accomplished through the synthesis of the disaccharide terminal residues in both a and ß configuration. Both entities were used to generate murine monoclonal antibodies which recognized the carbohydrate determinants. The determination of fine specificities of these antibodies was effected by means of cellular uptake, immunohistopathology and immunoscintigraphy. Examination of pathological specimens of human and canine tumor tissue indicated that the expressed antigen was in the β configuration. More than 89% of all human carcinomas tested expressed the antigen in the above anomeric form. The combination of synthetic antigens and monoclonal antibodies raised specifically against them provide us with invaluable tools for the study of tumor marker expression in humans and their respective animal tumor models.


1990 ◽  
Vol 29 (03) ◽  
pp. 120-124
Author(s):  
R. P. Baum ◽  
E. Rohrbach ◽  
G. Hör ◽  
B. Kornhuber ◽  
E. Busse

The effect of triiodothyronine (T3) on the differentiation of cultured neuroblastoma (NB) cells was studied after 9 days of treatment with a dose of 10-4 M/106 cells per day. Using phase contrast microscopy, 30-50% of NB cells showed formation of neurites as a morphological sign of cellular differentiation. The initial rise of the mitosis rate was followed by a plateau. Changes in cyclic nucleotide content, in the triphosphates and in the activity of the enzyme ornithine decarboxylase (ODC) were assessed in 2 human and 2 murine cell lines to serve as biochemical parameters of the cell differentiation induced by T3. Whereas the cAMP level increased significantly (3 to 7 fold compared with its initial value), the cGMP value dropped to 30 to 50% of that of the control group. ATP and GTP increased about 200%, the ODC showed a decrease of about 50%. The present studies show a biphasic effect of T3 on neuroblastoma cells: the initial rise of mitotic activity is followed by increased cell differentiation starting from day 4 of the treatment.


1988 ◽  
Vol 60 (02) ◽  
pp. 205-208 ◽  
Author(s):  
Paul A Kyrle ◽  
Felix Stockenhuber ◽  
Brigitte Brenner ◽  
Heinz Gössinger ◽  
Christian Korninger ◽  
...  

SummaryThe formation of prostacyclin (PGI2) and thromboxane A2 and the release of beta-thromboglobulin (beta-TG) at the site of platelet-vessel wall interaction, i.e. in blood emerging from a standardized injury of the micro vasculature made to determine bleeding time, was studied in patients with end-stage chronic renal failure undergoing regular haemodialysis and in normal subjects. In the uraemic patients, levels of 6-keto-prostaglandin F1α (6-keto-PGF1α) were 1.3-fold to 6.3-fold higher than the corresponding values in the control subjects indicating an increased PGI2 formation in chronic uraemia. Formation of thromboxane B2 (TxB2) at the site of plug formation in vivo and during whole blood clotting in vitro was similar in the uraemic subjects and in the normals excluding a major defect in platelet prostaglandin metabolism in chronic renal failure. Significantly smaller amounts of beta-TG were found in blood obtained from the site of vascular injury as well as after in vitro blood clotting in patients with chronic renal failure indicating an impairment of the a-granule release in chronic uraemia. We therefore conclude that the haemorrhagic diathesis commonly seen in patients with chronic renal failure is - at least partially - due to an acquired defect of the platelet a-granule release and an increased generation of PGI2 in the micro vasculature.


1974 ◽  
Vol 32 (02/03) ◽  
pp. 405-416 ◽  
Author(s):  
M. R Hardeman ◽  
Carina J L. Heynens

SummaryStorage experiments were performed at 4°, 25° and 37° C with platelet-rich plasma under sterile conditions. In some experiments also the effect of storing platelets at 4° C in whole blood was investigated.Before, during and after three days of storage, the platelets were tested at 37° C for their serotonin uptake and response to hypotonic shock. In addition some glycolytic intermediates were determined.A fair correlation was noticed between the serotonin uptake and hypotonic shock experiments. Both parameters were best maintained at 25° C. Also platelet counting, performed after the storage period, indicated 25° C as the best storage temperature. Determination of glycolytic intermediates did not justify any conclusion regarding the optimal storage temperature. Of the various anticoagulants studied, ACD and heparin gave the best results as to the serotonin uptake and hypotonic shock response, either with fresh or stored platelets. The use of EDTA resulted in the lowest activity, especially after storage.The results of these storage experiments in vitro, correspond well with those in vivo reported in the literature.


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