Zusammenfassung
Hintergrund und Zielsetzung: Wir haben in zwei Querschnittsumfragen in den Jahren 2012 und 2017 eine erhebliche Heterogenität im perioperativen Management von Antithrombotika unter ...Dermatologen in Deutschland festgestellt. Die erste deutsche Leitlinie zu diesem Thema wurde 2014 veröffentlicht und im Jahr 2021 aktualisiert. Wir wollten herausfinden, wie sich der Umgang mit Antithrombotika verändert hat.
Methodik: Wir haben eine papierbasierte Umfrage an 1115 Dermatologen in ganz Deutschland versandt und sie zu ihrem perioperativen Management von Antithrombotika bei Operationen an der Haut sowie zu ihrer Vertrautheit mit der Leitlinie befragt.
Ergebnisse: Wir erhielten Antworten von 65 stationär tätigen und 202 niedergelassenen Dermatologen. Die meisten Dermatologen gaben an, Antithrombotika bei kleineren Operationen fortzuführen. Ein nennenswerter Anteil der Dermatologen gab an, bei invasiveren Operationen die Behandlung mit Phenprocoumon perioperativ zu pausieren und mit Heparin zu überbrücken. Bei Kombinationstherapien war das Fortführen der Behandlung weniger verbreitet.
Schlussfolgerungen: Der Anteil der Dermatologen in Deutschland, die angaben, Antithrombotika bei Operationen an der Haut leitlinienkonform zu managen, ist seit 2012 gestiegen. Das Fortführen von Antithrombotika bei großen Exzisionen und Wächterlymphknotenexstirpationen, der Verzicht auf die Überbrückung von Phenprocoumon mit Heparin und das perioperative Fortführen antithrombotischer Kombinationstherapien müssen jedoch weiterhin propagiert werden, insbesondere unter niedergelassenen Dermatologen.
Zusammenfassung
Hintergrund und Zielsetzung:
Unser Ziel war es, das Komplikationsrisiko bei Operationen an der Haut beim perioperativen Pausieren im Vergleich zum Fortführen von Antithrombotika und ...beim perioperativen
Bridging
von Vitamin‐K‐Antagonisten mit Heparin im Vergleich zum Fortführen der Vitamin‐K‐Antagonisten zu evaluieren.
Methodik:
Wir führten einen systematischen Review durch und haben drei Datenbanken nach einschlussfähigen Studien durchsucht. Die Methodik folgte dem Cochrane Handbook. Wir verwendeten RoB 2 und ROBINS‐I, um das Verzerrungsrisiko zu bewerten. Die Qualität der Evidenz wurde bewertet (GRADE) und
fixed‐effect
‐Metaanalysen wurden durchgeführt.
Ergebnisse:
Zwei randomisierte kontrollierte Studien und 19 prospektive Kohortenstudien wurden eingeschlossen. Es ist unklar, ob das perioperative Fortführen von Acetylsalicylsäure das Risiko signifikanter postoperativer Blutungen (SPB) im Vergleich zum Pausieren erhöht (Risikodifferenz (RD) 0,004, 95 %‐Konfidenzintervall (KI) –0,003 bis 0,019).
Im Vergleich zum perioperativen Pausieren kann das Fortführen von Phenprocoumon das Risiko für SPB erhöhen (RD 0,02, 95 %‐KI 0,00 bis 0,05). Im Vergleich zum perioperativen Fortführen kann das
Bridging
von Phenprocoumon mit Heparin das Risiko für SPB erhöhen (RD 0,07, 95 %‐KI 0,01 bis 0,22). Für direkte orale Antikoagulantien wurde keine Evidenz hinsichtlich der Blutungsrisiken gefunden.
Schlussfolgerungen:
Es wurden keine eindeutigen Hinweise für erhebliche Blutungsrisiken beim perioperativen Fortführen von Antithrombotika bei kleineren Operationen an der Haut gefunden. Allerdings war die Qualität der Evidenz sehr niedrig.
Coronavirus disease-2019 (COVID-19) is associated with severe inflammation in mainly the lung, and kidney. Reports suggest a beneficial effect of the use of heparin/low molecular weight heparin ...(LMWH) on mortality in COVID-19. In part, this beneficial effect could be explained by the anticoagulant properties of heparin/LMWH. Here, we summarise potential beneficial, non-anticoagulant mechanisms underlying treatment of COVID-19 patients with heparin/LMWH, which include: (i) Inhibition of heparanase activity, responsible for endothelial leakage; (ii) Neutralisation of chemokines, and cytokines; (iii) Interference with leukocyte trafficking; (iv) Reducing viral cellular entry, and (v) Neutralisation of extracellular cytotoxic histones. Considering the multiple inflammatory and pathogenic mechanisms targeted by heparin/LMWH, it is warranted to conduct clinical studies that evaluate therapeutic doses of heparin/LMWH in COVID-19 patients. In addition, identification of specific heparin-derived sequences that are functional in targeting non-anticoagulant mechanisms may have even higher therapeutic potential for COVID-19 patients, and patients suffering from other inflammatory diseases.
A novel heparinase III from Pedobacter schmidteae (PsHep-III) with high activity and good stability was successfully cloned, expressed, and characterized. PsHep-III displayed the highest specific ...activity ever reported of 192.8 U mg–1 using heparin as the substrate. It was stable at 25 °C with a half-life of 323 h in an aqueous solution. PsHep-III was employed for the depolymerization of heparin, and the enzymatic hydrolyzed products were analyzed with gel permeation chromatography and high-performance liquid chromatography. PsHep-III can break glycosidic bonds in heparin like →4GlcNAc/GlcNAc6S/GlcNS/GlcNS6S/GlcN/GlcN6S(1 → 4)ΔUA/ΔUA2S1 → and efficiently digest heparin into seven disaccharides including N-acetylated, N-sulfated, and N-unsubstituted modification, with molecular masses of 503, 605, 563, 563, 665, 360, and 563 Da, respectively. These results indicated that PsHep-III with broad substrate specificity could be combined with heparinase I to overcome the low selectivity at the N-acetylated modification binding sites of heparinase I. This work will contribute to the application of PsHep-III for characterizing heparin and producing low-molecular-weight heparin effectively.
This chapter describes the pharmacology of approved parenteral anticoagulants, including the indirect anticoagulants, unfractionated heparin (UFH), low-molecular-weight heparins (LMWHs), ...fondaparinux, and danaparoid as well as the direct thrombin inhibitors hirudin, bivalirudin, and argatroban. UFH is a heterogeneous mixture of glycosaminoglycans that bind to antithrombin via a unique pentasaccharide sequence and catalyze the inactivation of thrombin factor Xa and other clotting factors. Heparin also binds to cells and other plasma proteins, endowing it with unpredictable pharmacokinetic and pharmacodynamic properties, and can lead to nonhemorrhagic side effects, such as heparin-induced thrombocytopenia (HIT) and osteoporosis. LMWHs have greater inhibitory activity against factor Xa than thrombin and exhibit less binding to cells and proteins than heparin. Consequently, LMWH preparations have more predictable pharmacokinetic and pharmacodynamic properties, have a longer half-life than heparin, and have a lower risk of nonhemorrhagic side effects. LMWHs can be administered once or twice daily by subcutaneous injection, without anticoagulant monitoring. Based on their greater convenience, LMWHs have replaced UFH for many clinical indications. Fondaparinux, a synthetic pentasaccharide, catalyzes the inhibition of factor Xa, but not thrombin, in an antithrombin-dependent fashion. Fondaparinux binds only to antithrombin; therefore, HIT and osteoporosis are unlikely to occur. Fondaparinux has excellent bioavailability when administered subcutaneously, has a longer half-life than LMWHs, and is given once daily by subcutaneous injection in fixed doses, without anticoagulant monitoring. Three parenteral direct thrombin inhibitors and danaparoid are approved as alternatives to heparin in HIT patients.
Thrombosis and inflammation may contribute to the risk of death and complications among patients with coronavirus disease 2019 (Covid-19). We hypothesized that therapeutic-dose anticoagulation may ...improve outcomes in noncritically ill patients who are hospitalized with Covid-19.
In this open-label, adaptive, multiplatform, controlled trial, we randomly assigned patients who were hospitalized with Covid-19 and who were not critically ill (which was defined as an absence of critical care-level organ support at enrollment) to receive pragmatically defined regimens of either therapeutic-dose anticoagulation with heparin or usual-care pharmacologic thromboprophylaxis. The primary outcome was organ support-free days, evaluated on an ordinal scale that combined in-hospital death (assigned a value of -1) and the number of days free of cardiovascular or respiratory organ support up to day 21 among patients who survived to hospital discharge. This outcome was evaluated with the use of a Bayesian statistical model for all patients and according to the baseline d-dimer level.
The trial was stopped when prespecified criteria for the superiority of therapeutic-dose anticoagulation were met. Among 2219 patients in the final analysis, the probability that therapeutic-dose anticoagulation increased organ support-free days as compared with usual-care thromboprophylaxis was 98.6% (adjusted odds ratio, 1.27; 95% credible interval, 1.03 to 1.58). The adjusted absolute between-group difference in survival until hospital discharge without organ support favoring therapeutic-dose anticoagulation was 4.0 percentage points (95% credible interval, 0.5 to 7.2). The final probability of the superiority of therapeutic-dose anticoagulation over usual-care thromboprophylaxis was 97.3% in the high d-dimer cohort, 92.9% in the low d-dimer cohort, and 97.3% in the unknown d-dimer cohort. Major bleeding occurred in 1.9% of the patients receiving therapeutic-dose anticoagulation and in 0.9% of those receiving thromboprophylaxis.
In noncritically ill patients with Covid-19, an initial strategy of therapeutic-dose anticoagulation with heparin increased the probability of survival to hospital discharge with reduced use of cardiovascular or respiratory organ support as compared with usual-care thromboprophylaxis. (ATTACC, ACTIV-4a, and REMAP-CAP ClinicalTrials.gov numbers, NCT04372589, NCT04505774, NCT04359277, and NCT02735707.).
Heparin and anticoagulation Onishi, Akihiro; St Ange, Kalib; Dordick, Jonathan S ...
Frontiers in bioscience (Landmark. Print),
06/2016, Volume:
21, Issue:
7
Journal Article
Peer reviewed
Heparin, a sulfated polysaccharide, has been used as a clinical anticoagulant for over 90 years. Newer anticoagulants, introduced for certain specialized applications, have not significantly ...displaced heparin and newer heparin-based anticoagulants in most medical procedures. This chapter, while reviewing anticoagulation and these newer anticoagulants, focuses on heparin-based anticoagulants, including unfractionated heparin, low molecular weight heparins and ultra-low molecular weight heparins. Heparin's structures and its biological and therapeutic roles are discussed. Particular emphasis is placed on heparin's therapeutic application and its adverse effects. The future prospects are excellent for new heparins and new heparin-based therapeutics with improved properties.
Re-visiting the structure of heparin Casu, Benito; Naggi, Annamaria; Torri, Giangiacomo
Carbohydrate research,
02/2015, Volume:
403
Journal Article
Peer reviewed
•Metamorphosis of the structure of heparin over the years.•History of identification and chemical synthesis of major and minor sequences, among which the specific pentasaccharidic sequence of the ...active site for antithrombin.•Peculiar conformational properties of iduronic acid-containing heparin sequences and proof of their role in protein binding and eliciting biological activities.
The sulfated polysaccharide heparin has been used as a life-saving anticoagulant in clinics well before its detailed structure was known. This mini-review is a survey of the evolution in the discovery of the primary and secondary structure of heparin. Highlights in this history include elucidation and synthesis of the specific sequence that binds to antithrombin, the development of low-molecular-weight heparins currently used as antithrombotic drugs, and the most promising start of chemo-enzymatic synthesis. Special emphasis is given to peculiar conformational properties contributing to interaction with proteins that modulate different biological properties.
This guideline addressed VTE prevention in hospitalized medical patients, outpatients with cancer, the chronically immobilized, long-distance travelers, and those with asymptomatic thrombophilia.
...This guideline follows methods described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.
For acutely ill hospitalized medical patients at increased risk of thrombosis, we recommend anticoagulant thromboprophylaxis with low-molecular-weight heparin (LMWH), low-dose unfractionated heparin (LDUH) bid, LDUH tid, or fondaparinux (Grade 1B) and suggest against extending the duration of thromboprophylaxis beyond the period of patient immobilization or acute hospital stay (Grade 2B). For acutely ill hospitalized medical patients at low risk of thrombosis, we recommend against the use of pharmacologic prophylaxis or mechanical prophylaxis (Grade 1B). For acutely ill hospitalized medical patients at increased risk of thrombosis who are bleeding or are at high risk for major bleeding, we suggest mechanical thromboprophylaxis with graduated compression stockings (GCS) (Grade 2C) or intermittent pneumatic compression (IPC) (Grade 2C). For critically ill patients, we suggest using LMWH or LDUH thromboprophylaxis (Grade 2C). For critically ill patients who are bleeding or are at high risk for major bleeding, we suggest mechanical thromboprophylaxis with GCS and/or IPC at least until the bleeding risk decreases (Grade 2C). In outpatients with cancer who have no additional risk factors for VTE we suggest against routine prophylaxis with LMWH or LDUH (Grade 2B) and recommend against the prophylactic use of vitamin K antagonists (Grade 1B).
Decisions regarding prophylaxis in nonsurgical patients should be made after consideration of risk factors for both thrombosis and bleeding, clinical context, and patients' values and preferences.
PDF
