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Reviews The practical management of intracerebral hemorrhage associated with oral anticoagulant therapy Luca Masotti 1 , Mario Di Napoli 2 , Daniel A. Godoy 3 , Daniela Rafanelli 4 , Giancarlo Liumbruno 5 , Nicholas Koumpouros 6 , Giancarlo Landini 7 , Alessandro Pampana 1 , Roberto Cappelli 8 , Daniela Poli 9 , and Domenico Prisco 9 Oral anticoagulant-associated intracerebral hemorrhage is in- creasing in incidence and is the most feared complication of therapy with vitamin K1 antagonists. Anticoagulant-associated intracerebral hemorrhage has a high risk of ongoing bleeding, death, or disability. The most important aspect of clinical management of anticoagulant-associated intracerebral hemor- rhage is represented by urgent reversal of coagulopathy, de- creasing as quickly as possible the international normalized ratio to values r1 . 4, preferably r1 . 2, together with life support and surgical therapy, when indicated. Protocols for anticoagu- lant-associated intracerebral hemorrhage emphasize the im- mediate discontinuation of anticoagulant medication and the immediate intravenous administration of vitamin K1 (mean dose: 10–20 mg), and the use of prothrombin complex concen- trates (variable doses calculated estimate circulating functional prothrombin complex) or fresh-frozen plasma (15–30 ml/kg) or recombinant activated factor VII (15–120 lg/kg). Because of cost and availability, there is limited randomized evidence compar- ing different reversal strategies that support a specific treatment regimen. In this paper, we emphasize the growing importance of anticoagulant-associated intracerebral hemorrhage and de- scribe options for acute coagulopathy reversal in this setting. Additionally, emphasis is placed on understanding current con- sensus-based guidelines for coagulopathy reversal and the challenges of determining best evidence for these treatments. On the basis of the available knowledge, inappropriate adher- ence to current consensus-based guidelines for coagulopathy reversal may expose the physician to medico-legal implications. Key words: adverse affects, factor VII, fresh-frozen plasma, intracerebral hemorrhage, prothrombin complex concentrate, treatment, vitamin K antagonists, warfarin Introduction Vitamin K antagonists (VKA) are a class of anticoagulants that represent one of the main classes of drugs used in cardiovas- cular medicine; 1–15% of the population in western countries have been the subject of VKA or so-called oral anticoagulant therapy (OAT) (1), with widespread use over the past two decades (2, 3). However, clinical practitioners resist using OAT (4, 5), especially in elderly patients, due to their difficult management and the risk of severe bleeding complications (6). Intracerebral hemorrhage (ICH) represents the most serious and feared complication of VKA. This review is focused on the therapeutic strategies used to reverse coagulopathy in patients who develop acute nontrau- matic ICH while on OAT. Physicians should embrace new practices: reverse the coagulopathy as soon as possible to avoid further hematoma growth treat the initial underlying cause of ICH independently to the treatment of the coagulopathy treat small hemorrhage sizes aggressively and quickly be- cause patients with a better prognosis could worsen with hematoma expansion, and revert anticoagulation in patients with a therapeutic inter- national normalized ratio (INR), and not necessarily with a major level of INR (Table 1). Basic principles in VKA therapy The available VKA are represented by warfarin, acenocou- marol, and phenprocoumon, which differ for the different DOI: 10.1111/j.1747-4949.2011.00595.x Conflict of Interest: None declared. Correspondence: Luca Masotti , UO Medicina Interna Ospedale di Cecina, Via Montanara, Localita ` Ladronaia, 57023, Cecina (Li), Italy. E-mail: [email protected] 1 Internal Medicine, Cecina Hospital, Cecina, Italy 2 Neurological Service, San Camillo de’ Lellis General Hospital, Rieti, Italy 3 Neurointensive Care Unit, Sanatorio Pasteur, Catamarca, Argentina 4 Transfusion Medicine, Pistoia Hospital, Pistoia, Italy 5 Transfusion Medicine and Clinical Pathology, San Giovanni Calibita Fatebenefratelli Hospital, Rome, Italy 6 Neurosurgery, S.S. Filippo e Nicola Hospital, Avezzano, Italy 7 Internal Medicine, Santa Maria Nuova Florence Hospital, Florence, Italy 8 Thrombosis Center, University of Siena, Siena, Italy 9 Department of Medical and Surgical Critical Care, University of Florence, Thrombosis Center, Florence, Italy & 2011 The Authors. International Journal of Stroke & 2011 World Stroke Organization Vol 6, June 2011, 228–240 228
Transcript
  • Reviews

    The practical management of intracerebral hemorrhageassociated with oral anticoagulant therapy

    Luca Masotti1, Mario Di Napoli2, Daniel A. Godoy3, Daniela Rafanelli4,Giancarlo Liumbruno5, Nicholas Koumpouros6, Giancarlo Landini7, Alessandro Pampana1,

    Roberto Cappelli8, Daniela Poli9, and Domenico Prisco9

    Oral anticoagulant-associated intracerebral hemorrhage is in-

    creasing in incidence and is the most feared complication of

    therapywith vitamin K1 antagonists. Anticoagulant-associated

    intracerebral hemorrhage has a high risk of ongoing bleeding,

    death, or disability. The most important aspect of clinical

    management of anticoagulant-associated intracerebral hemor-

    rhage is represented by urgent reversal of coagulopathy, de-

    creasing as quickly as possible the international normalized

    ratio tovaluesr1.4, preferablyr1.2, togetherwith life supportand surgical therapy, when indicated. Protocols for anticoagu-

    lant-associated intracerebral hemorrhage emphasize the im-

    mediate discontinuation of anticoagulant medication and the

    immediate intravenous administration of vitamin K1 (mean

    dose: 1020mg), and the use of prothrombin complex concen-

    trates (variable doses calculated estimate circulating functional

    prothrombin complex) or fresh-frozen plasma (1530ml/kg) or

    recombinant activated factor VII (15120lg/kg). Because of cost

    and availability, there is limited randomized evidence compar-

    ingdifferent reversal strategies thatsupportaspecific treatment

    regimen. In this paper, we emphasize the growing importance

    of anticoagulant-associated intracerebral hemorrhage and de-

    scribe options for acute coagulopathy reversal in this setting.

    Additionally, emphasis is placed on understanding current con-

    sensus-based guidelines for coagulopathy reversal and the

    challenges of determining best evidence for these treatments.

    On the basis of the available knowledge, inappropriate adher-

    ence to current consensus-based guidelines for coagulopathy

    reversalmay expose the physician tomedico-legal implications.

    Key words: adverse affects, factor VII, fresh-frozen plasma,

    intracerebral hemorrhage, prothrombin complex concentrate,

    treatment, vitamin K antagonists, warfarin

    Introduction

    Vitamin K antagonists (VKA) are a class of anticoagulants that

    represent one of the main classes of drugs used in cardiovas-

    cular medicine; 115% of the population inwestern countrieshave been the subject of VKA or so-called oral anticoagulant

    therapy (OAT) (1), with widespread use over the past two

    decades (2, 3). However, clinical practitioners resist using OAT

    (4, 5), especially in elderly patients, due to their difficult

    management and the risk of severe bleeding complications

    (6). Intracerebral hemorrhage (ICH) represents the most

    serious and feared complication of VKA.

    This review is focused on the therapeutic strategies used to

    reverse coagulopathy in patients who develop acute nontrau-

    matic ICH while on OAT.

    Physicians should embrace new practices:

    reverse the coagulopathy as soon as possible to avoid furtherhematoma growth

    treat the initial underlying cause of ICH independently tothe treatment of the coagulopathy

    treat small hemorrhage sizes aggressively and quickly be-cause patients with a better prognosis could worsen with

    hematoma expansion, and

    revert anticoagulation in patients with a therapeutic inter-national normalized ratio (INR), and not necessarily with a

    major level of INR (Table 1).

    Basic principles in VKA therapy

    The available VKA are represented by warfarin, acenocou-

    marol, and phenprocoumon, which differ for the differentDOI: 10.1111/j.1747-4949.2011.00595.x

    Conflict of Interest: None declared.

    Correspondence: Luca Masotti, UO Medicina Interna Ospedale diCecina, Via Montanara, Localita` Ladronaia, 57023, Cecina (Li), Italy.

    E-mail: [email protected] Medicine, Cecina Hospital, Cecina, Italy2Neurological Service, San Camillo de Lellis General Hospital, Rieti, Italy3Neurointensive Care Unit, Sanatorio Pasteur, Catamarca, Argentina4Transfusion Medicine, Pistoia Hospital, Pistoia, Italy5Transfusion Medicine and Clinical Pathology, San Giovanni Calibita

    Fatebenefratelli Hospital, Rome, Italy6Neurosurgery, S.S. Filippo e Nicola Hospital, Avezzano, Italy7Internal Medicine, Santa Maria Nuova Florence Hospital, Florence, Italy8Thrombosis Center, University of Siena, Siena, Italy9Department ofMedical and Surgical Critical Care, University of Florence,

    Thrombosis Center, Florence, Italy

    & 2011 The Authors.International Journal of Stroke & 2011 World Stroke Organization Vol 6, June 2011, 228240228

  • plasma half-life. VKA drugs act on the liver by inhibiting g-carboxylation of glutamate residues on the N-terminal regions

    of vitamin K-dependent coagulation factors (factor II, VII, IX,

    and X) (6) (Fig. 1).

    Themain indicators for OATare represented by prophylaxis

    in patients with cardioembolic sources, primary or secondary

    prophylaxis of venous thromboembolism, and thromboem-

    bolic prophylaxis in patients with prothrombotic syndromes

    (79). The efficacy and safety of OAT depends on the quality

    controlmonitoring of the therapy. The bleeding complications

    increase with increasing INR values. The risk of bleeding

    doubles with each increment of one unit in the INR value.

    INR445 represents the most significant risk factor for

    bleeding in patients with OAT increasing bleeding risk by

    about six times (7, 10) (Fig. 2).

    Bleeds secondary to OAT are classified as either major or

    minor (11). Bleeds are classified major if it:

    occurs in critical organs, the brain, retro-peritoneum,peritoneum, chest, spinal cord, joints, gastro-intestinal tract

    results in a hemorrhagic shock, a decrease of 2 g/dl inhemoglobin levels, requires surgical or invasive maneuvers, or

    results in death.The remaining bleeds are classified as minor bleeds (11).

    Bleeding complications can be reduced, and the accurate

    selection of patients absolute and relative contraindications

    for OAT, patient monitoring in an anticoagulation clinic

    Intrinsic pathway

    FXII FXIIa

    FXI FXIa

    FIX FIXa

    FVIII FVIIIa FX FXa

    Prothrombin (FII) Thrombin (FIIa)

    FV FVa

    Fibrin monomerFibrinogen

    Fibrin multimer

    Crosslinked fibrin

    Extrinsic pathway

    Tissue injury

    FVIIa FVII

    Fig. 1 Sites of action (red) of oral anticoagulants in the clotting cascade.

    Table 1 The NIKE principles in the reversal of anticoagulant-associated intracerebral hemorrhage

    N5Normalize Normalize INR (and other coagulation parameters) as soon as possible

    I5 Immediate All patients should have immediate coagulopathy reversal, even if hemorrhage is small and clinical condition is good

    K5Vitamin K1 Initial correction must include longer-acting agents (e.g. vitamin K1) to avoid rebound INR elevation later.

    E5 Elevation of INR Level of INR elevation does not influence timing of reversal. All levels of INR elevation (modest o20, therapeutic 2030,supratherapeutic430) require urgent correction

    INR, international normalized ratio.

    0

    2

    4

    6

    8

    10

    1.9-2.0 2.4-2.7 3.1-3.4 3.7-4.3 4.9-5.7 6.6-8.0Estimated International Normalized Risk (INR) values

    Odd

    s Ra

    tio fo

    r int

    racr

    ania

    lbl

    eedi

    ng ri

    sk

    Fig. 2 Risk of intracerebral hemorrhage in outpatients according to INR levels. INR, international normalized ratio.

    & 2011 The Authors.International Journal of Stroke & 2011 World Stroke Organization Vol 6, June 2011, 228240 229

    L. Masotti et al. Reviews

  • (specifically designed for monitoring OAT patients), together

    with the self OATmonitoring (6), have contributed (12).

    The risk factors for bleeds in patients with OAT are as

    follows:

    advanced age severe liver and kidney diseases severe thrombocytopenia history of previous bleeding anemia dementia, and risk of falls (6).

    Some genetic polymorphisms for enzymes involved in the

    metabolism of VKA drugs, such as hepatic cytochrome P450

    (CYP2C92 and CYP2C93) and enzyme vitamin K epoxidereductase complex sub unit 1 (VKORC1), represent adjunctive

    risk factors, identifying patients who require small doses of

    VKA to reach the therapeutic range (13, 14).

    Practical scores may help in identifying the bleeds risk of

    each patient on OAT.

    The Outpatients Bleeding Risk Index considers four inde-

    pendent predictors of bleeding:

    age465 years prior stroke prior gastrointestinal bleeding, and any of four comorbidities (recent myocardial infarction,anemia, diabetes, or renal insufficiency) (15).

    The most recent HEMORR2HAGES score, which includes

    genetic polymorphisms, is shown in Fig. 3a and b (16).

    However, the current clinical usefulness of this one is poor

    and routine use might not significantly change the choice of

    OAT in elderly patients (17).

    Optimal anticoagulation with VKA is clinically challenging

    because of various patient food and drug interactions. Fluc-

    tuations in dietary vitamin K intake can have a significant

    effect on the degree of anticoagulation in patients treated with

    VKA. The interactions with many drugs (azole antibiotics,

    macrolides, quinolones, nonsteroidal anti-inflammatory

    drugs, including selective cyclooxygenase-2 inhibitors, selec-

    tive serotonin reuptake inhibitors, omeprazole, lipid-lowering

    agents, amiodarone, and fluorouracil) suggest that coadmi-

    nistration with VKA should be avoided or at least closely

    monitored (18). In addition, an increase of patient use of

    various dietary herbal products and supplements can

    lead to undesired outcomes on anticoagulant levels of

    warfarin (19), increasing bleeds risk (20). Case reports have

    described an association between their use and ICH due to a

    possible antiplatelet effect and VKA potentiate (21, 22).

    Because this information is not from human research trials,

    it is prudent to avoid the use of herbal agents in patients

    who are taking VKA medications and patients and health

    care providers should be vigilant of potential herbdrug

    interactions (23).

    VKA and intracerebral hemorrhagic risk

    The OAT-associated ICH (OAT-ICH) represents major bleed-

    ing, resulting in a life-threatening condition, sometimes fatal.

    The risk of OAT-ICH is of 0206% per year of treatment (24,25). The individual patient cumulative risk of bleeding is

    directly related to the length of OAT. Higher frequencies of

    bleeding are reported early in the course of therapy; the

    frequency of major bleeding decreased from 30% duringthe first month of outpatient OAT therapy to 08%/monthsduring the rest of the first year of therapy and to 03%/monthsthereafter (26). Approximately 70% of OAT-ICH are intracer-

    ebral, whereas 30% are in the subarachnoid space. The

    OAT-ICH represent about 15% of all ICH, with incidence

    estimated in the general population of about 18/100 000 in-habitants/year and 800010 000 new cases expected every year

    in the United States (25, 27, 28). As the use of VKA has

    Points

    1 Liver diseaseRenal disease 1

    1Alcoholism 1Cancer 1 Age > 75 yeras Platelets count < 75000/mm 3 1 Concomitant antiplatelets treatment 1 1Previous bleeding Uncontrolled arterial blood hypertension 1 Haemotocrit < 30% 1 CYP2C9*2 or CYP2C9*3 presence 1 High risk of falls or cognitive

    impairment 1 1Previous stroke

    (a) (b)

    Fig. 3 (a) The HEMORR2HAGES score. (b) Annual risk of hemorrhage according to HAEMORR2HAGES score.

    & 2011 The Authors.International Journal of Stroke & 2011 World Stroke Organization Vol 6, June 2011, 228240230

    Reviews L. Masotti et al.

  • increased, so has the incidence of OAT-ICH. In fact, VKAmay

    be associated with as many as 17% of ICH cases, up from

    5%20 years ago (29). Themost importantOAT-ICH incidence

    increase has been seen in patients aged more than 80 years,

    ranging from 25% in 1988 to 459% in 1999 (29). Therisk of ICH increases significantly when OAT is combined

    with other antithrombotic therapy (acetyl salicylic acid, ticlo-

    pidine, clopidogrel, unfractioned, or low-molecular-weight

    heparin) (6).

    Although in many cases OAT-ICH occurs in patients with a

    VKA overdose demonstrated by an outrange INR value, ICH

    can also occur in conditions of INR values within the

    therapeutic range. A recent casecontrol study shows that

    only 6% of patients with OAT-ICH were excessively antic-

    oagulated before the bleed, demonstrating that OAT use is

    associated with an increasing risk of ICH despite appropriate

    INR monitoring (30). Figure 4 shows an example of ICH in a

    patient with INR in the normal range.

    Triggering factors for an OAT-ICH in well-anticoagulated

    patients are:

    uncontrolled arterial hypertension head trauma rupture of an unknown intracranial aneurysm or an arter-ial-venous malformation

    leukoaraiosis amyloid microangiopathy primary or metastatic cerebral tumors, and unmonitored concomitant occasional therapy leading to anincrease of INR (31).

    Cerebral microbleeds (MB) are known to be indicative of

    bleeding-prone microangiopathy and potential risk factors for

    ICH (32, 33) with a close positional association between

    CT scan after 3 hours NIHSS 22 Glasgow Coma Scale 7/15 INR 0.7 The patient is transfered to Neurosurgical

    Department for haemorrhage evacuation

    Brain CT scan at hospital arrival of a female, 76-years old, about 60 kg of weight, in OAT for atrialfibrillation (suggested INR therapeutic range 2.0-3.0, target 2.5)

    INR at hospital arrival 3.2 NIHSS 6 Clasgow Coma Scale 12/15 Treatment with PCC (Uman Complex, Kedrion,

    Castelvecchio Pascoli, Lucca, Italy)at dosage of 1500 UI in five minutes followed byraFVII (Novoseven, NovoNordisk) at dosage of1.2mg in five minutes and vitamin K1 (Konakion,Roche) at dosage of 20 mg in 250 cc of salinesolution in thirty minutes

    (a) (b)

    Brain CT scan after 25 days Brain CT scan after neurosurgicalhaemorrhage evacuation

    (d)(c)

    Fig. 4 Example of spontaneous intracerebral hemorrhage in patient on oral anticoagulant therapy. CT, computed tomography; INR, international normalized

    ratio; PCC, prothrombin complex concentrate.

    & 2011 The Authors.International Journal of Stroke & 2011 World Stroke Organization Vol 6, June 2011, 228240 231

    L. Masotti et al. Reviews

  • recurrent ICH and prior MB (34). Excessive MB in OAT

    patients with ICH compared with other groups suggests that

    MB increase the risk of OAT-ICH (35) and underlying MB are

    independently associatedwith a higher incidence ofOAT-ICH.

    However, the risks and benefits of VKAmedication in patients

    with MB are not well defined (33).

    Thirty-day acute mortality for OAT-ICH is high, ranging

    from 12% to 60% (25, 36), and it is nearly doubled when

    compared with nonanticoagulated patients (37). However,

    hematoma volume and lower level of consciousness measured

    by the Glasgow Coma Scale but not INR levels are major

    determinants of a poor outcome in patients with OAT-ICH

    (38, 39). Hematoma enlargement is a major determinant of a

    poor prognosis in OAT-ICH. The OAT-ICH is associated with

    a greater baseline median ICH volume, more hemorrhage

    expansion, and greater mortality than spontaneous ICH (40).

    Experimental ICH animal models demonstrate that hema-

    toma volume increases drastically between two- and 24 h,

    hematoma volume increases steadily with increasing of INR

    values, and mortality is critically associated with hematoma

    volume (41). Although, in OAT-ICH patients, initial hema-

    toma volume seems not to be significantly different compared

    with non-OAT-ICH until INRr30, it is larger in OAT-ICHwith INR higher than 30 (4244). It has been demonstratedthat VKA-treated patients continue to bleed more often and

    for a longer duration compared with non-OAT-ICH (37).

    Approximately 50% of OAT-ICH patients present a secondary

    volume expansion compared with 17% of non-OAT-ICH

    patients (37).

    The time factor represents the most important variable in

    the OAT-ICH patient prognosis (45). Patients with suspected

    or confirmed OAT-ICH should be treated as a medical

    emergency. OAT reversal should start as soon as possible after

    symptom onset to prevent hematoma expansion (27). OAT

    reversal, together with surgical treatment, and support thera-

    pies such as reduction of blood hypertension and hemostatic

    therapy represent the possible effective options to restrict

    secondary hematoma expansion in OAT-ICH (46).

    Practical management of OAT-ICH

    Post OAT-ICH, it is possible and important to make an urgent

    OAT reversal. Key measures to reverse OAT in patients with

    OAT-ICH can be achieved through the immediate disconti-

    nuation of OAT and three different pathways:

    direct competition by administering vitamin K1 replacement of native coagulation factors by using fresh-frozen plasma (FFP) or a prothrombin complex concentrate

    (PCC), and

    by-passing the central part of the coagulation cascadethrough the use of recombinant activated factor VII (rFVIIa)

    (6, 47).

    The goal of these therapeutic measures is to decrease the

    INR values to levelsr14, preferablyr12 (6, 8, 25, 4853).The different pharmacological and blood product options

    have specific characteristics related to ease of administration,

    timing and duration of effect, and cost, which may potentially

    influence the choice of their use. The specific options for OAT

    reversal should be used complementary to general therapeutic

    measures for ICH and life support (51).

    Vitamin K1

    The administration of vitamin K1 (phytomenadione) is the

    first point of any warfarin reversal strategy. However, it has a

    slow action onset, making it a poor choice as a single agent. To

    effectively reverse the effect of warfarin, vitamin K1 usually

    takes at least two- to six-hours, and frequently 1224 h (6, 8,

    25, 49, 50). The effect of vitamin K1 is more rapid when given

    intravenously (IV) (53, 54). Vitamin K1 is inexpensive, but

    anaphylaxis (three per 10 000doses) froman IVadministration

    has reduced its use (27, 54). Because of the short half-life and

    duration of action of other OATreversal measures, vitamin K1

    should be administered in all patients in order to avoid a

    rebound in coagulopathy (1020mg in 250ml of normal saline

    in about 30mins, infusion rate being 1mg/min), with the aim

    of inducing de novo hepatic synthesis of vitamin K-dependent

    coagulation factors and of achieving the stabilization of OAT

    reversal (6, 8, 25, 4853). Subcutaneous and oral administra-

    tions represent alternative routes because they do not carry the

    same anaphylaxis risk as the IV route; however, the onset of

    action is not as rapid or reliable, especially when neurological

    status is compromised. Therefore, in OAT-ICH, the IVroute is

    preferred (6, 8, 25, 4853).

    PCC

    Prothrombin complex concentrates represent a generic term

    for several products that are derived from plasma and contain

    factors II, VII, IX, and X in different concentrations. PCC is

    considered the first therapeutic choice in OAT-ICH (6, 8, 25,

    4853, 55). Originally designed as factor IX concentrates, there

    are at least 10 different PCC products that are available in

    different parts of theworld and contain varying levels of factors

    II and X, and low levels of factor VII (56, 57). The most

    widespread types of PCC generally contain three or four

    vitamin K-dependent factors. Generally, PCC with three

    factors do not contain factor VII. It has been suggested that

    PCC containing three vitamin K-dependent coagulation fac-

    tors could be less effective in reversal OAT, and thus, in some

    situations, the addition of rFVIIa may be warranted (58).

    However, in a prospective study, considering about 90 patients

    with spontaneous and traumatic ICH, Imberti et al. (36)

    reached the goal to obtain an INRr15 30mins postadminis-tration of a PCC containing three factors (factors II, IX, and X)

    in 75% of patients, and maintained this benefit until 96 h after

    administration in 98% of patients, with a very low 30-day

    mortality (about 12%). Ameta-analysis (n5 460 patients) has

    demonstrated the effectiveness of the PCC in determining the

    rapid OAT reversal, the superiority of the PCC over the FFP

    & 2011 The Authors.International Journal of Stroke & 2011 World Stroke Organization Vol 6, June 2011, 228240232

    Reviews L. Masotti et al.

  • and/or vitamin K1, reducing the times of OAT reversal, with-

    out cases of disseminated intravascular coagulation and low

    thrombotic risk (15%) (59).The PCC are available as a concentrate, which can be

    reconstituted to a total volume of about 50150ml and

    delivered in 1030mins depending on the volume and rate

    of infusion. The PCC infusion dose is dependent on body

    weight; it is related to INR and is based on a dose of factor IX

    necessary to reversal (56). For each international unit of

    PCC per kg of body weight, the plasma concentration of factor

    IX increases by 1%(60). Table 2 summarizes the recommended

    dose of PCC to be infused in patients with OAT-ICH. Optimal

    PCC dosing (INR-based vs. a standardized fixed dose) remains

    somewhat controversial, although individualized dosing

    may ensure INR correction more rapidly. PCC can correct

    the INR within minutes (36). Thus, they are very good agents

    for acuteOATreversal because of the small volume, the range of

    coagulation factors provided, and the rapid onset of action.

    However, PCC are significantly more expensive than vitamin

    K1 and FFP (6, 8, 25, 4853, 55). When using PCC prepara-

    tions with low amounts of factor VII, coadministration of

    one- to two-units of FFP or rFVIIa may also be considered

    (8, 50, 55).

    FFP

    Fresh-frozen plasma is the most common agent utilized in

    OAT-ICH, especially in the United States, where 60% of

    consumed FFP is used for OAT reversal (61). The FFP is a

    blood product that contains all the coagulation factors. How-

    ever, the actual levels of vitamin K-dependent clotting factors

    in each unit of FFP are not standardized and may vary widely.

    Table 3 shows the average content of individual coagulation

    factors present in a single unit of FFP as reported by Blood

    Transfusion Task Force of British Committee for Standards in

    Haematology (62). Anyway, the ordinary FFP unit is inevitably

    subject to the biological variability associated with a single

    donor (63). Furthermore, the infusion of FFP has some risks.

    In particular, it may be necessary to use large volumes of

    plasma to correct the coagulation defect. Initial doses of 15ml/

    kg of FFP are suggested (6, 8, 25, 49, 50, 62), although there is

    evidence that a dose of 30ml/kg produces more complete

    correction of coagulation factor levels (60, 6467). Although

    the required volume of FFP somewhat depends on the initial

    INR, the target INR is the more relevant issue. According to a

    recent study, the difference in the predicted FFP transfusion

    volume between an INR goal of 13 and 17 is two-liters ofplasma at all initial INRs. This represents a significant patient

    overload volume with potentially dangerous effects in the

    elderly and cardio pulmonary disease patients (66). Further-

    more, in these patients, the infusion rate should not be too

    quick and this can lead to delays in OAT reversal. The FFP

    Table 2 How to choose the dose of PCC or FFP for urgent warfarin

    reversal: calculated or fixed dose

    INR value Estimated functional PC

    Calculated dose

    First step: Convert INR to % of estimated circulating functional

    prothrombin complex (PC)

    Z5 5%4049 10%2632 15%2225 20%1921 25%1718 30%1416 40%1013 100%Second step

    Calculate the dose:

    IU of PCCorml of FFP needed to be infused5 (Target in%of PC to be

    reachedcurrent estimated % of PC) kg of body weightExample:

    Present INR 45 corresponding to estimated functional PC 10%Target INR 14 corresponding to estimated functional PC 40%Body Weight 70 kg

    IU needed to be infused5 (4010) 705 2100 IU of PCCor 2800mlof FFP

    INR value PCC dose (IUkg) FFP dose (ml/kg)

    Fixed dose

    1520 20 152040 3040 1530Z40 50 1530Example:

    Present INR 45Body weight 70 kg

    IU needed to be infused5 3500 IU of PCC or 10502100ml of FFP

    Adapted from Aguilar et al. (25).INR, international normalized ratio;

    PCC, prothrombin complex concentrate; FFP,fresh-frozen plasma.

    Table 3 Average composition of 250300ml of fresh-frozen plasma

    after thawing at 41C

    Levels after

    thawing (41C)Levels

    after 24 h

    Levels after

    five days

    Fibrinogen 260270mg/dl 220230mg/dl 220230mg/dl

    Factor II 80 IU 80 IU 80 IU

    Factor V 80 IU 75 IU 65 IU

    Factor VII 90 IU 80 IU 70 IU

    Factor VIII 90 IU 50 IU 40 IU

    Factor IX 100 IU / /

    Factor X 85 IU 85 IU 80 IU

    Factor XI 100 IU / /

    Factor XII 80 IU / /

    Factor XIII 100 IU / /

    Antithrombin 100 IU / /

    Von Willebrand

    factor

    80 IU / /

    Adapted from British Committee for Standards in Hematology, Blood

    Transfusion Task Force (62).

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    L. Masotti et al. Reviews

  • requires compatibility testing and thawing before administra-

    tion; there is an inherent delay in initiating FFP transfusion

    (62, 67). Thanks to the introduction of several preventive

    measures, the residual risk for the three major viral infections

    (i.e., hepatitis B virus, hepatitis C virus, HIV/AIDS) is cur-

    rently very low (68). Anyway, other equally life-threatening

    risks of FFP transfusion are far more common, such as severe

    allergic reactions (69), transfusion-associated circulatory over-

    load (70), and transfusion-related acute lung injury (71).

    Because of these considerations, FFP should be used in the

    OAT- ICH if PCC is not available (60).

    rFVIIa

    Recombinant activated factor VII is an approved medication

    for the treatment of hemophilia.

    Randomized clinical trials (RCT) have evaluated the benefit

    of avoiding enlargement of hematoma in the acute phase of

    spontaneous noncoagulopathic ICH and using off-label for

    VKA-related ICH as well as traumatic hemorrhage (7275).

    The rFVIIa promotes hemostasis at sites of vascular rupture,

    limiting hematoma enlargement after ICH. Preliminary results

    have shown a reduction in hematoma volume increase,

    mortality, and better functional status after a three-month

    administration of rFVIIa, despite a 5% increase in arterial

    thromboembolic phenomena (76). The phase III FAST trial

    showed no significant difference in mortality or severe dis-

    ability at 90 days between different dosages of rFVIIa and

    placebo, but confirmed the hemostatic effect and thromboem-

    bolic complications (77). In conclusion, the use of rFVIIa

    reduces the growth of the hematoma but does not improve

    patient survival or functional outcome after ICH; in addition,

    rFVIIa increases the incidence of arterial thromboembolic

    complications (78). On the basis of these results, routine

    utilization of rFVIIa as ultra-early hemostatic therapy for all

    patients with ICH cannot be recommended. However, the use

    of rFVIIa in conjunctionwith FFP is associated with shortened

    times to correction of INR and reduced the total dose of FFP

    required for the correction of coagulopathy in OAT-ICH

    patients (79).

    As with PCC, rFVIIa has the advantage of limited volume

    infusions; even low doses of rFVIIa correct prothrombin time.

    INR values cannot be used as a reliable indicator of cessation of

    bleeding in patients who have received rFVIIa. A single IV dose

    can normalize the INR within minutes; however, it is very

    important to keep in mind that INR might increase in

    subsequent hours due to the short-half-life of rFVIIa, and

    therefore, the drug infusion requires strict follow-up and

    monitoring (80). It is not known whether other emerging

    coagulation tests such as thromboelastography might be

    useful. The dose of rFVIIa for OAT-ICH is not standardized

    and optimal dosing is not known. The rFVIIa is administered

    as a single, one-time bolus over two- to five-minutes ranging

    from 15 to 120mg/kg (mean dose 8090 mg/kg) (25, 27). Largedoses are associated with a longer duration of effect (81).

    Until now, rFVIIa has not been a recognized for the

    treatment of OAT-associated bleeding and therefore its use in

    these situations is considered off-label (81, 82), even though

    suggested by the 2008 American College of Chest Physicians

    Guidelines on Antithrombotic Therapy as an alternative to

    PCCor FFPwith a grade of recommendation IC (6). Among all

    the current warfarin-reversal options, rFVIIa, however, is the

    most expensive.

    Whatever measures are chosen, the INR should be checked

    at the end of the infusion, and then every three-hours when the

    INR is corrected to confirm its stability. If INR monitoring

    reveals a value Z15, an additional dose of reversal therapyshould be administered (6, 8, 50, 55). Table 4 summarizes the

    advantages and limitations of each measure of OAT reversal.

    The role and timing of surgery in OAT-ICHWhen reaching the goal of OATreversal, neurosurgical evacua-

    tion of the hematoma should be warranted when indicated

    (51, 52, 83). Figure 4 (c,d) shows an example of neurosurgical

    hematoma evacuation after OATreversal. Given the absence of

    strong scientific evidence to indicate a prominent role of

    Table 4 Options for urgent warfarin reversal

    Agent Pros Cons

    Usefulness for

    urgent reversal

    Vitamin K1 Widely available; inexpensive; directly reverses

    warfarin effect; small volume infused; low infec-

    tive and thrombotic risk

    Slow onset of action; possible allergy Poor

    Fresh-frozen plasma Widely available; contains all coagulation factors;

    low thrombotic risk

    Large volumes usually needed; requires cross-

    matching and thawing; slow onset of action; not

    negligible infective risk, possible TRALI

    Fair

    Prothrombin complex

    concentrate

    Rapid onset; small volume infused; low infective

    risk

    Expensive; variable factor concentrations in differ-

    ent preparations; not negligible thrombotic risk

    Good

    Recombinant activated

    factor VII

    Rapid onset; small volume infused; thrombin

    burst; low infective risk

    Very expensive; acts directly ononly a single factor;

    INR correction may be lab artifact; off label use

    Good

    TRALI, transfusion acute lung injury.

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    Reviews L. Masotti et al.

  • surgery in determining the outcome, this measure should be

    performed in a tailored manner. With the exceptions of the

    placement of a ventricular drain in patients with hydrocepha-

    lus and evacuation of a large posterior fossa hematoma, the

    timing and nature of other neurosurgical interventions is also

    controversial. In practice, surgery is performed as a life-saving

    measure in patients with large hematomas or cortical hemor-

    rhages and secondary neurologic deterioration. American and

    European guidelines recommend surgery for patients with

    lobar supratentorial hemorrhages within 1 cm of the cortical

    surface, particularly for those with good neurological status

    who are deteriorating clinically. For patients with profound

    sited hemorrhages (basal ganglia, thalamic) and mass effect,

    guidelines suggest evacuation with minimally invasive meth-

    ods within 12 h (51, 52). Urgent surgical removal of infra-

    tentorial hematomas larger than 3 cm is frequently associated

    with remarkable recoveries. There is substantial evidence that

    the management of patients with ICH in a neurointensive care

    unit, where treatment is directed toward monitoring and

    managing cardiorespiratory variables and intracranial pres-

    sure, is associated with improved outcomes. Attentionmust be

    paid to fluid and glycemicmanagement,minimizing the risk of

    ventilator-acquired pneumonia, fever control, provision of

    enteral nutrition, and thromboembolic prophylaxis.

    There is a robust theoretical basis supporting early surgery.

    An aggressivemanagement in the acute phase can be translated

    into improved outcomes after ICH (84). Specific treatment

    approaches include early diagnosis and hemostasis, aggressive

    management of blood pressure, open surgical and minimally

    invasive surgical techniques to remove clot, techniques to

    remove intraventricular blood, and management of intracra-

    nial pressure (84). The OAT-ICHmay produce a great volume

    hematoma with mass effect, edema, obstructive hydrocepha-

    lus, midline shift, intracranial hypertension, herniations, and

    death; thus, surgery is a therapeutic possibility. Surgical

    evacuation may prevent hematoma expansion, decrease in-

    tracranial pressure, mass effect, and prevent the release of

    neurotoxic products. Despite these hypothetical benefits,

    surgery remains controversial, without a clear demonstra-

    tion of efficacy when compared with standardmedical therapy

    (83, 85).

    Most surgeons follow guidelines for clot removal similar to

    those applied for spontaneous hematomas of nonanticoagu-

    lated patients (51), although the analysis of available clinical

    data suggests that patient subgroups that mostly benefit from

    surgery are different from anticoagulated patients. The litera-

    ture lacks evidence on the effect of early surgery in antic-

    oagulated and rapidly worsening patients becausemost studies

    on the surgical evacuation of ICH have considered patients

    already treated for correction of INR (83, 86). A study

    performed at theMayoClinic suggests that emergency evacua-

    tion for deteriorating patients with large OAT-ICH is compa-

    tible with a favorable outcome independent of anticoagulation

    reversal (87). Time shortening of OAT reversal is crucial both

    for spontaneous and for posttraumatic ICH to be submitted to

    neurosurgery evacuation (88). Ultra-rapid reversal of antic-

    oagulation could reduce the time to biological and surgical

    hemostasis, and might improve outcome (89). In this case,

    neurosurgery could be performed immediately with results

    comparable to those of nonanticoagulated patients. However,

    guidelines note than there is evidence that ultra-early surgery

    (within four-hours) is associated with an increased risk of

    rebleeding and higher mortality (475%) (90). Future rando-mized studies should aim to individuate with higher accuracy

    patients who certainly may benefit from surgical treatment.

    Furthermore, the role of surgery in OAT-ICH should be

    reevaluated in the light of recent technological advances.

    Minimally invasive techniques may allow a more efficient

    and less traumatic evacuation of the hematoma (91, 92).

    Current evidence: benefits, concerns,and challenges

    Currently, there are no prospective, randomized, controlled

    clinical trials comparing the various VKA-reversal strategies.

    There are no controlled trials assessing whether or not PCC or

    rFVIIa are superior to a strategy of FFP and vitamin K1, or

    comparing PCC and rFVIIa regarding clinical outcome. How-

    ever, several small retrospective and prospective studies eval-

    uated the effectiveness of INR reversal obtained with the

    various agents (44, 74, 93, 94). In summary, they show that a

    reversal of INR within two-hours from hospital admission is

    associated with low rates of hematoma enlargement and is

    achieved in the majority of patients (84%) treated with PCC,

    while FFP infusions show only a partial effect in reducing

    hematoma enlargement (39%) and vitamin K1 has no effects

    (93). In patients with ICH-related coagulopathies of different

    etiologies who need neurosurgical interventions, the reversal

    of INR before surgery attempted with FFP and rFVIIa is

    quicker (mean seven-hours), without thrombotic complica-

    tions, with a better functional outcome (95). The beneficial

    effect after the reversal of anticoagulation using different

    agents is also evident in patients with acute clinical worsening

    and a marked mass effect who have emergency surgical

    evacuation of hematomas (87). These studies show that there

    is limited evidence to support a specific treatment regimen for

    VKA-related ICH. Randomized trials using patient mortality

    and neurological function as outcomes have been proposed.

    However, they do not appear to be easy to carry out due to the

    large sample size required, the frequent poor outcome of OAT-

    ICH patients, and variability in available products in different

    areas of the world. Thus, current approaches derivemore from

    consensus-based guidelines driven from concern for rapid and

    safe coagulopathy correction.

    The risk of thrombotic events afterOATreversal is a problem

    that has affected this type of treatment strategy in patients with

    acute OAT-associated bleeding for a long time, although the

    percentages of thrombosis are variable on the basis of the

    differentOATreversal treatments used, ranging from0% to 7%

    (25). In many cases, physicians do not have alternative choices

    & 2011 The Authors.International Journal of Stroke & 2011 World Stroke Organization Vol 6, June 2011, 228240 235

    L. Masotti et al. Reviews

  • to reverse OAT adverse effects, particularly if hemorrhage is

    severe enough to endanger the life of the patient. Goldstein

    and colleagues have shown that the 30-day incidence of

    arterial and venous thromboembolic events is about 5% for

    patients with OAT-ICH in which OAT is discontinued,

    lower than that reported in patients with non-OAT-

    ICH (72%) (96), whereas Imberti et al. (36) did notobserve thrombotic complications during hospitalization of

    OAT-ICH treated with PCC. However, thrombotic events in

    the acute phase of OAT-ICH seem not to influence 30-day

    mortality (96). Mechanical prophylaxis should be pre-

    scribed to patients with OAT-ICH to prevent venous throm-

    boembolism (97).

    The time for OAT should be restarted after an ICH is an

    important question. For each patient, the balance between the

    thrombotic risk due to the coexistent thromboembolic disease

    for which OAT was prescribed and the risk of bleeding

    recurrence should be carefully evaluated.

    A casecontrol study enrolling approximately 50 patients

    compared a group of patients in which OAT was restarted

    after ICH with one in which OAT was not restarted, and

    showed that the risk of ICH recurrences could be low in

    those who restarted therapy, whereas the incidence of throm-

    botic events could not be negligible in those who did not

    restart OAT (98). A very recent review of clinical studies and

    case series by Romualdi et al. (99) has demonstrated an

    incidence of 29% of ICH recurrence after restarting OAT inpatients with prosthetic heart valves suffering from a first

    episode of ICH. It is suggested by experts to restart OAT

    therapy in patients with prosthetic mechanical heart valves, in

    most cases one-week from the hemorrhagic event, while

    some concerns exist in restarting OAT in nonvalvular atrial

    fibrillation (25).

    In patients after OAT-associated major bleeding,

    ACCP guidelines suggest the possibility of reducing OAT

    intensity, for example prescribing a range of INR between

    20 and 25 in prosthetic mechanical heart valves andbetween 15 and 20 in patients with atrial fibrillation togetherwith a close monitoring of INR to avoid the risk of overdose

    (6) or to replace mechanical with bioprosthetic valves in

    selected patients (6). For OAT-ICH in patients with venous

    thromboembolism, caval filters placement is indicated

    to prevent a first episode or a recurrence of pulmonary

    embolism (100).

    Treatment algorithms and guidelines

    Despite the lack of evidence from RCT, there are several

    international consensus-based guidelines that address the

    treatment regimen in OAT-ICH patients (6, 11, 5052, 55).

    All guidelines emphasize the high morbidity of OAT-ICH,

    the urgency of rapid reversal of coagulopathy, the use of

    vitamin K1 (usually IV), and the use of PCC, given the rapid

    onset of action with these agents and the shortcomings of

    FFP alone. However, none provides a specific target INR

    for an adequate reversal and the lack of clear evidence

    limits the ability to make strong recommendations about the

    agent and the dose to be used. Any intracranial bleeding

    in a patient on VKA, independent of INR levels when

    Z15, should be considered as a life-threatening conditionregardless of the hematoma size or the patients clinical status

    at the first evaluation, because of the high risk of ongoing

    hemorrhage, the high fatality rate, and the residual severe

    disability fromOAT-ICH (Fig. 5). Themain recommendations

    are summarized in Table 5.

    Fig. 5 Proposed algorithm for Hyperacute VKA reversal. CT, computed tomography; FFP, fresh-frozen plasma; INR, international normalized ratio; PCC,

    prothrombin complex concentrate; OAT-ICH, oral anticoagulant-associated intracerebral hemorrhage; rFVIIa, recombinant activated factor VII; VKA, vitamin

    K antagonist.

    & 2011 The Authors.International Journal of Stroke & 2011 World Stroke Organization Vol 6, June 2011, 228240236

    Reviews L. Masotti et al.

  • Conclusion

    The incidence of OAT-ICH has increased recently because it is

    associated with a high risk of ongoing bleeding, death, or

    disability. Urgent reversal of coagulopathy is the highest

    priority. Several agents such as vitamin K1, PCC, rFVIIa,

    and/or FFP are available, and there are pros and cons in the

    use of each of them. They should be included in the qualifica-

    tion of every physician who might have to treat a patient

    receiving such therapy. The incorrect or the late management

    of therapeutic measures for OAT reversal in the case of ICH

    may expose the physician to the risk of legal prosecution,

    because effective and safe antidotes are available (101). There-

    fore, it is not acceptable that the reversal of OAT is delayed or

    incomplete or even omitted. A call for action is needed to

    develop a uniform approach for physicians in themanagement

    of patients on OAT, and it is particularly desirable that each

    hospital is equipped with internal protocols derived from

    recognized guidelines (Fig. 5).

    All protocols for OAT-ICH emphasize the immediate cessa-

    tion of the anticoagulant medication and the immediate

    administration of vitamin K1 (IV). The use of PCC or rFVIIa

    may reverse coagulopathy more rapidly than FFP alone;

    however, randomized trials testing this are yet to be initiated.

    Furthermore, the cost and availability of these agentsmay limit

    their widespread use. In the near future, new oral antithrom-

    botic drugs will be used (and will possibly replace VKAs) for

    the prophylaxis and treatment of arterial and venous throm-

    boembolic disease. Among these, dabigatran, rivaroxaban, and

    apixaban are the most studied and have already been shown to

    be effective and safe (102105). After the recent Phase III trial

    RE-LY (randomized evaluation of long-term anticoagulation

    therapy), the use of dabigatran in atrial fibrillation is more

    clearly defined. The results show that the 110-mg dose of

    dabigatran was associated with similar rates of stroke and

    systemic embolism (primary end points) and lower rates of

    major hemorrhage when compared with warfarin; the 150mg

    dose of dabigatran was associated with lower rates of stroke

    and systemic embolism but with a similar rate of major

    hemorrhage (106).

    However, among the main limitations of these new drugs,

    the absence of a specific antidote in bleeding complications

    could influence their use in clinical practice. Whatever the

    antidotes tested for the treatment of the new antithrombotic,

    drug-related bleedings consist of PCC, FFP, and rFVIIa;

    hence, their knowledge could also be useful for this new

    scenario (107, 108).

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