====== Direct Oral Anticoagulant ====== {{ ::anticoagulant.jpg?300|}} Oral [[anticoagulant]] was first established in [[1941]] by Karl Paul Link, who discovered [[dicumarol]] ((Campbell HA, Roberts WL, Smith WK, Link KP. Studies of the hemorrhagic sweet clover disease. I. The preparation of hemorrhagic concentrates. J Biol Chem. 1940;136:47–55.)). ---- DOACs were associated with better [[efficacy]] and [[safety]] profiles than [[warfarin]] in [[atrial fibrillation]] patients with prior [[stroke]], more specifically a lower risk of systemic [[embolism]], all-cause mortality, and [[intracranial hemorrhage]] (ICH) ((Umashankar K, Mammi M, Badawoud E, Tang Y, Zhou M, Borges JC, Liew A, Migliore M, Mekary RA. Efficacy and Safety of Direct Oral Anticoagulants (DOACs) Versus Warfarin in Atrial Fibrillation Patients with Prior Stroke: a Systematic Review and Meta-analysis. Cardiovasc Drugs Ther. 2022 Apr 25. doi: 10.1007/s10557-022-07336-w. Epub ahead of print. PMID: 35467313.)). ===== Novel oral anticoagulants ===== [[Novel oral anticoagulant]]s. ===== Vitamin K oral anticoagulant ===== see [[Vitamin K oral anticoagulant]]. ===== Non vitamin K oral anticoagulant ===== see [[Non vitamin K oral anticoagulant]]. ===== Complications ===== [[Oral anticoagulant complications]] ---- Oral [[vitamin K antagonist]]s (VKAs) were the choice of [[anticoagulant]] for the long-term [[treatment]] and [[prevention]] of arterial and venous [[thromboembolic event]]s (VTE). VKA treatment is safe and effective if a high time in the therapeutic range is achieved. However, achieving a stable, therapeutic [[international normalized ratio]] can prove challenging in the context of drug and food interactions and [[liver]] [[disease]], resulting in either an increased risk of [[thromboembolism]] due to undertreatment or [[bleeding]] due to overtreatment. In recent years, four direct [[oral anticoagulant]]s (DOACs), [[dabigatran]], [[rivaroxaban]], [[apixaban]] and [[edoxaban]], have been compared with [[warfarin]] for [[stroke]] prevention in [[atrial fibrillation]] (AF), in large, phase 3, [[randomized controlled trial]]s (RCTs). Various terms have been used to describe these drugs, including new/ novel [[oral anticoagulant]]s or non-vitamin K oral anticoagulants. The International Society on Thrombosis and Haemostasis recommends using the term ‘DOAC’ (Direct Oral Anticoagulant) ((Barnes GD, Ageno W, Ansell J, Kaatz S. Recommendation on the nomenclature for oral anticoagulants: communication from the SSC of the ISTH: reply. J Thromb Haemost. 2015 Nov;13(11):2132-3. doi: 10.1111/jth.13136. Epub 2015 Sep 30. PMID: 26340598.)) ===== Direct Oral Anticoagulant in Neurosurgery ===== {{rss>https://pubmed.ncbi.nlm.nih.gov/rss/search/1pWbXSyt-bgKwwdDzZrGqU8jRdhLchzLQ3sF-SW1ghXMmnuYGD/?limit=15&utm_campaign=pubmed-2&fc=20240206065413}} ===== Reversal ===== [[Direct Oral Anticoagulant Reversal Agents]] ===== Perioperative management ===== There is little [[evidence]] to guide the [[perioperative]] management of patients on a [[direct oral anticoagulant]] (DOAC) in the absence of a last known dose. Quantitative serum titers may be ordered. A preoperative DOAC assay order was associated with worse outcomes despite increased reversal administration. However, the DOAC assay titer can reflect the patient's likelihood of bleeding ((Stretton B, Kovoor J, Bacchi S, Booth A, Gluck S, Vanlint A, Afzal M, Ovenden C, Gupta A, Mahajan R, Edwards S, Brennan Y, Boey JP, Reddi B, Maddern G, Boyd M. Impact of perioperative direct oral anticoagulant assays: a multicenter cohort study. Hosp Pract (1995). 2023 Apr 21. doi: 10.1080/21548331.2023.2206270. Epub ahead of print. PMID: 37083232.)). ===== Case series ===== A study aimed to assess the outcomes of patients with [[traumatic intracranial hemorrhage]] taking DOACs compared with those taking warfarin. A retrospective analysis of patients with traumatic ICH over a 5-year period was conducted. Demographics, injury severity, medication, and outcome data were collected for each patient. Patients taking warfarin and DOACs were compared. 736 patients had traumatic ICH over the study period, 75 of which were on either DOACs (25 patients) or warfarin (50 patients). The median age of the anticoagulated patients was 78 years; 52% were female, and 91% presented secondary to a fall. DOACs were reversed at close to half the rate of warfarin (40% vs 77%; P = .032). Despite this, the 2 groups had similar rates of worsening examination, need for operative intervention, and in-[[Hospital mortality]]. In the follow-up, fewer patients taking DOACs had died at 6-months postinjury compared with those taking warfarin (8% vs 30%; P = .041). Despite DOACs being reversed at nearly half the rate of warfarin, patients presenting with traumatic ICH on warfarin had higher 6-month mortality suggesting a potential survival advantage for DOACs over warfarin in this population ((Billings JD, Khan AD, McVicker JH, Schroeppel TJ. Newer and Better? Comparing Direct Oral Anticoagulants to Warfarin in Patients With Traumatic Intracranial Hemorrhage. Am Surg. 2020 Sep;86(9):1062-1066. doi: 10.1177/0003134820942204. Epub 2020 Aug 16. PMID: 33049165.)). ==== 2018 ==== Beynon et al. analyzed the medical records of consecutive patients treated at our institution for acute SDH during anticoagulation therapy with [[Direct oral anticoagulant]]s (DOAC) or vitamin K antagonists (VKA) during a period of 30 months. Patient characteristics such as results of imaging and laboratory studies, treatment modalities and short-term patient outcomes were included. A total of 128 patients with preadmission DOAC (n = 65) or VKA (n = 63) intake were compared. The overall 30-day mortality rate of this patient cohort was 27%, and it did not differ between patients with DOAC or VKA intake (26% vs. 27%; p = 1.000). Similarly, the rates of neurosurgical intervention (65%) and intracranial re-hemorrhage (18%) were comparable. Prothrombin complex concentrates were administered more frequently in patients with VKA intake than in patients with DOAC intake (90% vs. 58%; p < 0.0001). DOAC treatment in patients with acute SDH did not increase in-hospital and 30-day mortality rates compared to VKA treatment. These findings support the favorable safety profile of DOAC in patients, even in the setting of intracranial hemorrhage. However, the availability of specific antidotes to DOAC may further improve the management of these patients ((Beynon C, Brenner S, Younsi A, Rizos T, Neumann JO, Pfaff J, Unterberg AW. Management of Patients with Acute Subdural Hemorrhage During Treatment with Direct Oral Anticoagulants. Neurocrit Care. 2018 Oct 31. doi: 10.1007/s12028-018-0635-4. [Epub ahead of print] PubMed PMID: 30382531.)). ===== References =====