Warfarin and intracranial haemorrhage

Comparative effectiveness and safety of oral anticoagulants for atrial fibrillation: A retrospective cohort study

Oral anticoagulants (OACs) are high-priority medications, frequently used with clinically important benefit and serious harm. Our objective was to compare the safety and effectiveness of direct-acting oral anticoagulants (DOACs) versus warfarin in a population where anticoagulation management and DOACs were readily available. A retrospective cohort study of all adults living in British Columbia with a diagnosis of atrial fibrillation and a first prescription for an OAC was conducted. Co-primary outcomes were ischemic stroke and systemic embolism, and major bleeding. Secondary outcomes included a net clinical outcome composite and analysis of discontinuation, switching, and key subgroups. We estimated the effects of treatment using time-to-event models with high-dimensional propensity score adjustment to control confounding. After adjustment for prescribing bias, a cohort (n = 20,113, 43.8% female, mean age 72.4 years) with a mean follow-up of 18.1 months showed that patients taking warfarin tended to be poorer, sicker, and less likely to have a cardiologist prescriber. Outcome event rates were not significantly different for DOACs compared to warfarin [adjusted rate ratio of 1.15 (0.91, 1.46) for systemic embolism, 0.94 (0.82, 1.08) for major bleeding, and 0.98 (0.90, 1.06) for net clinical outcome]. Only the effect of age on net clinical outcome met our strict criteria for predicting which group might be superior. Switch of drug class was associated with increased risk of events (p < 0.003). In this population, we found no difference in important clinical outcomes between warfarin and DOACs. Switching compared to not switching was associated with harm.

Three-Factor Versus Four-Factor Prothrombin Complex Concentrate for the Emergent Management of Warfarin-Associated Intracranial Hemorrhage

BACKGROUND

Four-factor prothrombin complex concentrates (PCC) produce a more rapid and complete INR correction compared with 3-factor PCC in patients receiving warfarin. It is unknown if this improves clinical outcomes in the setting of intracranial hemorrhage (ICH).

METHODS

This multicenter, retrospective cohort study included patients presenting with warfarin-associated ICH reversed with either 4- or 3-factor PCC. The primary outcome was in-hospital mortality. Secondary outcomes were 30-day mortality, discharge location, intensive care unit (ICU) and hospital-free days, INR reversal, and thromboembolic (TE) events at 90 days. Each was analyzed using regression analysis. Continuous and binary outcomes were analyzed using linear and logistic regression, respectively, while ordinal regression was used for discharge location.

RESULTS

Of the 103 patients, 63 received 4-factor PCC. Median age was 79 years [interquartile intervals(IQI 73-84)], median presenting INR was 2.7 (2.2-3.3), and presenting ICH was intraparenchymal in 51% of patients. In-hospital and 30-day mortality were 25 and 35%, respectively. In-hospital mortality was greater among those who received 4-factor PCC, yet was not statistically significant (OR 2.2, 95% CI 0.59-9.4, p = 0.26), as having Glasgow Coma Scale (GCS) ≤8 explained most of the difference (OR 48, 95% CI 14-219, p <0.001). The effect of 4-factor PCC was not statistically significant in any of the secondary analyses. Crude rates of TE events were higher in the 4-factor PCC group (19 vs. 10%), though not significantly.

CONCLUSIONS

In-hospital mortality was not improved with the use of 4- versus 3-factor PCC in the emergent reversal of warfarin-associated ICH. Secondary clinical outcomes were similarly nonsignificant.

Quality of Chronic Anticoagulation Control in Patients with Intracranial Haemorrhage due to Vitamin K Antagonists

Introduction

Patients treated with vitamin K antagonists (VKA) are at increased risk of intracranial haemorrhage (ICH). The purpose of our study was to determine the quality of previous anticoagulation control in patients with VKA-associated ICH.

Materials and Methods

We prospectively assessed every consecutive patient admitted to our stroke unit with VKA-associated ICH between 2013 and 2016. Demographic, clinical, and radiological variables, as well as consecutive international normalized ratios (INR) during 7 previous months, were extracted. Time in therapeutic range (TTR), time over range (TOR), time below range (TBR), and percentage of INR within range (PINRR) were calculated.

Results and Discussion

The study population comprised 53 patients. Mean age was 79 years; 42% were women. Forty-eight patients had atrial fibrillation (AF) and 5 mechanical prosthetic valves. Therapeutic or infratherapeutic INR on arrival was detected in 64.4% of patients (95% CI 2.7 to 3.2). TTR was 67.8% (95% CI: 60.2 to 75.6 %) and PINRR was 75% (95% CI: 49.9-100). TOR was 17.2% (95% CI: 10.4 to 23.9% ) and TBR was 17% (95% CI: 10.6 to 23.9%).

Conclusion

VKA-associated ICH happens usually in the context of good chronic anticoagulation control. Newer risk assessment methods are required.

The Severity of Intracranial Hemorrhages Measured by Free Hemoglobin in the Brain Depends on the Anticoagulant Class: Experimental Data

Background and Purpose. Anticoagulant therapy is broadly used to prevent thromboembolic events. Intracranial hemorrhages are serious complications of anticoagulation, especially with warfarin. Direct oral anticoagulants reduce but do not eliminate the risk of intracranial hemorrhages. The aim of this study is to determine the degree of intracranial hemorrhage after application of anticoagulants without additional triggers. Methods. Rats were treated with different anticoagulant classes (vitamin K antagonists, heparin, direct thrombin inhibitor, and factor Xa inhibitor). Brain hemorrhages were assessed by the free hemoglobin concentration in the brain parenchyma. Results. Vitamin K antagonists (warfarin and brodifacoum) significantly increased free hemoglobin in the brain. Among direct oral anticoagulants, thrombin inhibitor dabigatran also significantly increased free hemoglobin in the brain, whereas treatment with factor Xa inhibitor rivaroxaban did not have significant effect on the free hemoglobin concentration. Conclusions. Our data indicates that the severity of brain hemorrhages depends on the anticoagulant class and it is more pronounced with vitamin K antagonists.

Intracranial hemorrhage in patients with atrial fibrillation receiving anticoagulation therapy

We investigated the frequency and characteristics of intracranial hemorrhage (ICH), the factors associated with the risk of ICH, and outcomes post-ICH overall and by randomized treatment. We identified patients with ICH from the overall trial population enrolled in the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation trial who received ≥1 dose of the study drug (n = 18 140). ICH was adjudicated by a central committee. Cox regression models were used to identify factors associated with ICH. ICH occurred in 174 patients; most ICH events were spontaneous (71.7%) versus traumatic (28.3%). Apixaban resulted in significantly less ICH (0.33% per year), regardless of type and location, than warfarin (0.80% per year). Independent factors associated with increased risk of ICH were enrollment in Asia or Latin America, older age, prior stroke/transient ischemic attack, and aspirin use at baseline. Among warfarin-treated patients, the median (25th, 75th percentiles) time from most recent international normalized ratio (INR) to ICH was 13 days (6, 21 days). Median INR prior to ICH was 2.6 (2.1, 3.0); 78.5% of patients had a pre-ICH INR <3.0. After ICH, the modified Rankin scale score at discharge was ≥4 in 55.7% of patients, and the overall mortality rate at 30 days was 43.3% with no difference between apixaban- and warfarin-treated patients. ICH occurred at a rate of 0.80% per year with warfarin regardless of INR control and at a rate of 0.33% per year with apixaban and was associated with high short-term morbidity and mortality. This highlights the clinical relevance of reducing ICH by using apixaban rather than warfarin and avoiding concomitant aspirin, especially in patients of older age. This trial was registered at www.clinicaltrials.gov as #NCT00412984.

Comparative effectiveness and safety of oral anticoagulants for atrial fibrillation in real-world practice: a population-based cohort study protocol

INTRODUCTION

Anticoagulants are arguably the most important drug family of all, based on the frequency and duration of their use, and the clinical importance and frequency of benefits and harms. Several direct acting oral anticoagulants (DOACs) have recently joined warfarin for the treatment of atrial fibrillation, with a resultant significant expansion in use of oral anticoagulants (OACs). Our objectives are to compare safety and effectiveness of DOACs versus warfarin in a full population where anticoagulation management is good and to identify which types of patients do better with DOACs versus warfarin and vice versa.

METHODS AND ANALYSIS

This is a retrospective cohort study of all adults living in British Columbia who have a diagnosis of atrial fibrillation in hospital or medical service data, and a first prescription for an OAC. Coprimary outcomes are ischaemic stroke and systemic embolism (benefit) and major bleeding (harm). Secondary outcomes include net clinical benefit (composite of stroke, systemic embolism, major bleeds, myocardial infarction, pulmonary embolism and death), drug discontinuation and individual composite item occurrence. We will estimate the effects of treatment in a 2-year follow-up period, using time-to-event models with propensity score adjustment to control confounding. Secondary analyses will examine 'as treated' outcomes.

ETHICS AND DISSEMINATION

The protocol, data creation plan, privacy impact statement and data sharing agreements have been approved. Dissemination is planned via conferences and publications as well as directly to drug policy leaders. Information on the overall comparative effectiveness and safety of DOACs versus warfarin in a country with high quality anticoagulation management, as well as for vulnerable subgroups, will be an important addition to the literature.

Management of anticoagulant-related intracranial hemorrhage: an evidence-based review

The increased use of anticoagulants for the prevention and treatment of thromboembolic diseases has led to a rising incidence of anticoagulant-related intracranial hemorrhage (AICH) in the aging western population. High mortality accompanies this form of hemorrhagic stroke, and significant and debilitating long-term consequences plague survivors. Although management guidelines for such hemorrhages are available for the older generation anticoagulants, they are still lacking for newer agents, which are becoming popular among physicians. Supportive care, including blood pressure control, and reversal of anticoagulation remain the cornerstone of acute management of AICH. Prothrombin complex concentrates are gaining popularity over fresh frozen plasma, and reversal agents for newer anticoagulation agents are being developed. Surgical interventions are options fraught with complications, and are decided on a case-by-case basis. Our current state of understanding of this condition and its management is insufficient. This deficit calls for more population-based studies and therapeutic trials to better evaluate risk factors for, and to prevent and treat AICH.

Effect of complexation with arabinogalactan on pharmacokinetics of "guest" drugs in rats: for example, warfarin

A pharmacokinetic study of the warfarin (WF) : arabinogalactan (AG) complex with the 1 : 10 mass ratio after its intragastric introduction to Wistar rats at a dose of 5 mg/kg (WF dose in the complex was 0.5 mg/kg) once a day for three days was conducted. It was found that C_max, T_1/2, and AUC of WF in the complex form were lower than after the introduction of blank WF at the same dose, but its elimination (Cl, MRT) was much faster. Significant accumulation (C_min) and an abrupt increase in plasma concentration after the third introduction were observed for blank WF, whereas the complex showed a much more moderate increase in concentration at this point. However, despite obvious differences in pharmacokinetic parameters, the efficacies of both agents were virtually identical; the complex differed from blank WF by only 15%. This value is rather insignificant and does not impair its anticoagulant activity. Thus, we can conclude that introduction of the WF : AG complex is safe in terms of reduction of the bleeding risk and accumulation.

Questionable reversal of anticoagulation in the therapeutic management of cerebral haemorrhage associated with vitamin K antagonists

Reversal of anticoagulation is recommended to correct the international normalised ratio (INR) for patients with intracranial haemorrhage (ICH) associated with vitamin K antagonists (VKA). However, the validity of such treatment is debated. We sought to identify, prospectively, the prognostic effect of VKA-ICH treatment in a cohort of patients (n=71; median age 78 years, range 20-89; 52% males). Data collated were: baseline characteristics, treatments, baseline and post-treatment INR, haematoma volume, and haematoma enlargement. Treatment effects and prognostic factor assessment were in relation to mortality and functional outcomes. On admission, the patients had a median score of 9 [p25; p75 of 5; 20] on the National Institute of Health Stroke Scale (NIHSS) and a mean INR of 2.7 (range: 0.9 - 10.8). Haematoma volume (34.6 cm³; SD: 24.9) correlated with NIHSS (r = 0.55; p<0.001) but not with INR. Anticoagulation reversal treatment was administered in 83% of patients. INR <1.5 was achieved in 60.7% of cases. Death or dependency at three months was 76%. Neither baseline INR, anticoagulation reversal nor haematoma enlargement were related to mortality or functional outcome. The only independent prognostic factor was clinical severity on admission. Baseline NIHSS predicted mortality (OR: 1.18; 95%CI: 1.09-1.27), independence (OR: 0.83; 95%CI: 0.74-0.94) and neurological recovery (NIHSS 0-1) (OR: 0.83; 95%CI: 0.73-0.95). The data indicate that VKA-ICH had a poor prognosis. Treatment and INR correction did not appear to affect outcomes.

Long-term outcome after anticoagulation-associated intracerebral haemorrhage with or without restarting antithrombotic therapy

BACKGROUND

For patients who survive intracerebral haemorrhage (ICH) during treatment with oral anticoagulation (OAC), the balance between the benefits and risks of restarting OAC is unclear. The decision to restart OAC or to start antiplatelet therapy in these patients therefore poses a dilemma for all physicians involved. We assessed the long-term outcome of patients who did or did not restart antithrombotic therapy after OAC-associated ICH.

METHODS

We conducted a retrospective follow-up study of all patients discharged from our institution after OAC-associated ICH over a 10-year period. Data on the use of OAC or platelet inhibitors and the occurrence of vascular events during follow-up were assessed through questionnaires and patient files. The primary outcome was recurrent fatal or non-fatal stroke. Secondary outcomes were the occurrence of other haemorrhagic, thrombotic or thromboembolic events. With patients without antithrombotic treatment as reference, we calculated incidence ratios with corresponding 95% confidence intervals (CI) for treatment with OAC and for treatment with antiplatelet therapy.

RESULTS

We included 38 patients, of whom 21 (55%) died during a mean follow-up of 3.5 years. The medication regime changed frequently during follow-up, illustrated by the fact that two thirds of the patients who had resumed OAC within 2 months of ICH terminated this at later points in time. Two recurrent strokes occurred during 35.4 patient-years without antithrombotic medication, 7 during 63.8 patient-years on antiplatelet medication (incidence ratio 1.9; 95% CI, 0.4-9.4), and 3 during 19.5 patient-years on OAC (incidence ratio 2.7; 95% CI, 0.5-16.3). There was only 1 recurrent ICH, which occurred during treatment with OAC.

CONCLUSION

In this observational study, no significant difference in the primary outcome measure was found between the treatment groups, but there was a tendency towards a higher long-term risk of any stroke in patients who resumed OAC or started antiplatelet therapy. However, based on these results it is difficult to draw any concrete conclusions or make any strong recommendations. A randomized trial to assess the optimal long-term strategy after OAC-related ICH is warranted. Based on the point estimates of our study, such a trial should involve at least 300 patient-years of follow-up.

Intracerebral hemorrhage in patients receiving oral anticoagulation therapy

Intracerebral hemorrhage (ICH) in patients with oral anticoagulation therapy is an increasingly prevalent problem in large part due to the aging population and the increased use of anticoagulants for patients at high risk of thrombosis. Warfarin has been virtually the only outpatient anticoagulant choice until fairly recently. The development of subcutaneously injected heparinoids, and more recently, of direct thrombin inhibitors, has made the treatment and prognostication of ICH in anticoagulated patients more difficult. In this review, we will review the current state of diagnosis, prognostication, and treatment for patients with this often-devastating type of bleeding. We will focus on warfarin therapy, because the preponderance of evidence comes from studies of warfarin treatment. Where there is evidence, we will contrast warfarin with some of the newer treatment modalities. We review the evidence of the 4 major reversal agents for warfarin, vitamin K, prothrombin complex concentrates, activated factor VII, and fresh frozen plasma as well as rational treatment choices. We offer possible treatments for the newer anticoagulants based on the limited evidence available. Finally, we review recommendations from the major societies and studies that support early and aggressive therapies in intensive care units with dedicated neurological specialists.

Mild elevations of international normalized ratio at hospital Day 1 and risk of expansion in warfarin-associated subdural hematomas

OBJECT

A primary goal in the treatment of patients with warfarin-associated subdural hematoma (SDH) is reversal of coagulopathy with fresh-frozen plasma. Achieving the traditional target international normalized ratio (INR) of 1.3 is often difficult and may expose patients to risks of volume overload and of thromboembolic complications. This retrospective study evaluates the risk of mild elevations of INR from 1.31 to 1.69 at 24 hours after admission in patients presenting with warfarin-associated SDH.

METHODS

Sixty-nine patients with warfarin-associated SDH and 197 patients with non-warfarin-associated SDH treated at a single institution between January 2005 and January 2012 were retrospectively identified. Charts were reviewed for patient age, history of trauma, associated injuries, neurological status at presentation, size and chronicity of SDH, associated midline shift, INR at admission and at hospital Day 1 (HD1), concomitant aspirin or Plavix use, platelet count, and medical comorbidities. Patients were stratified according to use of warfarin and by INR at HD1 (INR 0.8-1.3, 1.31-1.69, 1.7-1.99, and ≥ 2). The groups were evaluated for differences the in rate of radiographic expansion of SDH and in the rate of clinically significant SDH expansion resulting in death, unplanned procedure, and/or readmission.

RESULTS

There was no difference in the rate of radiographic versus clinically significant expansion of SDH between patients not on warfarin and those on warfarin (no warfarin: 22.3% vs 20.3%, p = 0.866; warfarin: 10.7% vs 11.6%, p = 0.825), but the rate of medical complications was significantly higher in the warfarin subgroup (13.3% for patients who did not receive warfarin vs 26.1% for those who did; p = 0.023). For warfarin-associated SDH, there was no difference in the rate of radiographic versus clinically significant expansion between patients reversed to HD1 INRs of 0.8-1.3 and 1.31-1.69 (HD1 INR 0.8-1.3: 22.5% vs 20%, p = 1; HD1 INR 1.31-1.69: 15% vs 10%, p = 0.71).

CONCLUSIONS

Mild INR elevations of 1.31-1.69 in warfarin-associated SDH are not associated with a markedly increased risk of radiographic or clinically significant expansion of SDH. Larger prospective studies are needed to determine if subtherapeutic INR elevations at HD1 are associated with smaller increases in risk of SDH expansion.

Successful management of an acute subdural hematoma in a patient dependent on continuous treprostinil infusion therapy

Treprostinil is a synthetic analog of prostacyclin, which is used for treatment of pulmonary arterial hypertension (PAH). Continuous subcutaneous administration of treprostinil has been proven in randomized controlled trials to improve quality of life, hemodynamics, and 5-year survival in patients with PAH. The efficacy of treprostinil has been attributed to its vasodilatory and antiplatelet effects. Unfortunately, the efficacy of treprostinil in the treatment of PAH is rapidly reversed upon cessation of the continuous infusion. Furthermore, cases of patients rapidly declining or succumbing to disease progression upon cessation of treprostinil have raised significant concern regarding discontinuation of this medication. To date, there are no reports of emergency craniotomies performed in the setting of continuous subcutaneous infusion of treprostinil. The authors report a case of a patient with PAH, treated with continuous administration of subcutaneous treprostinil as well as warfarin, who developed an acute subdural hematoma (SDH). Despite adequate INR (international normalized ratio) correction, the patient eventually underwent an emergency craniotomy for evacuation of the SDH while on continuous treprostinil administration. This case highlights the neurosurgical dilemma regarding the appropriate management of acute SDHs in patients receiving continuous treprostinil infusion.

Individual characteristics and management decisions affect outcome of anticoagulated patients with intracranial hemorrhage

BACKGROUND

Anticoagulated patients with intracranial hemorrhage represent a major management challenge. Our goal is to determine how patient characteristics and management decisions influence outcome.

METHODS

A systematic review of the literature identified relevant reported cases. Variables describing patient characteristics, management, and outcome were extracted. Statistical analyses were carried out using analysis of variance and Fisher's exact test.

RESULTS

A total of 242 patients from our updated dataset met inclusion criteria. Tissue plane of the hemorrhage (P < 0.0001), indication for anticoagulation (P < 0.0001), type of anticoagulant (P = 0.0173), and history of hypertension (P = 0.0418) were significantly associated with outcome. Older age (P < 0.0001), supratentorial index hemorrhages (P = 0.0018), failure to restart anticoagulation (P < 0.0001), and larger hematoma volume (P < 0.0001) were associated with worse outcome. Surgical evacuation was associated with improved outcome (P = 0.0011). There was a trend toward an association between the occurrence of a hemorrhagic or thromboembolic complication and risk of death (P = 0.0882). Sex and sidedness of the index hemorrhage were not significantly associated with outcome.

CONCLUSIONS

Our results provide prognostic information that may assist management of these patients. Our results also suggest that it may be unwise to withhold anticoagulation indefinitely after an index hemorrhage. As thromboembolic or hemorrhagic complications may be associated with worse outcome, efforts to avoid them may be wise. The studies that comprise our dataset have important limitations and a prospective study will be required to confirm these results.

Atrial fibrillation and thromboprophylaxis in heart failure: the need for patient-centered approaches to address adherence

Atrial fibrillation is a common arrhythmia in heart failure and a risk factor for stroke. Risk assessment tools can assist clinicians with decision making in the allocation of thromboprophylaxis. This review provides an overview of current validated risk assessment tools for atrial fibrillation and emphasizes the importance of tailoring individual risk and the importance of weighing the benefits of treatment. Further, this review provides details of innovative and patient-centered methods for ensuring optimal adherence to prescribed therapy. Prior to initiating oral anticoagulant therapy, a comprehensive risk assessment should include evaluation of associated cardiogeriatric conditions, potential for adherence to prescribed therapy, frailty, and functional and cognitive ability.

Thromboembolic risks of recombinant factor VIIa Use in warfarin-associated intracranial hemorrhage: a case-control study

BACKGROUND

Recombinant factor VIIa (rFVIIa) may be used for rapid hemostasis in life-threatening hemorrhage. In warfarin-associated intracerebral hemorrhage (wICH), FVIIa use is controversial and may carry significant thromboembolic risks. We compared incidence of baseline thromboembolic risk factors and thromboembolism rates in wICH patients treated with additional rFVIIa to those treated with standard therapy of fresh frozen plasma (FFP) and vitamin K alone.

METHODS

We identified 45 consecutive wICH patients treated with additional rFVIIa over 5-year period, and 34 consecutive wICH patients treated with standard therapy alone as comparison group. We compared the incidence of post-hemorrhage cardiac and extra-cardiac thromboembolic complications between two treatment groups, and used logistic regression to adjust for significant confounders such as baseline thromboembolic risk factors. We performed secondary analysis comparing the quantity of FFP transfused between two treatment cohorts.

RESULTS

Both rFVIIa-treated and standard therapy-treated wICH patients had a high prevalence of pre-existing thromboembolic diseases including atrial fibrillation (73% vs 68%), deep venous thrombosis (DVT) or pulmonary embolism (PE) (22% vs 18%), coronary artery disease (CAD) (38% vs 32%), and abnormal electrocardiogram (EKG) (78% vs 85%). Troponin elevation following wICH was prevalent in both groups (47% vs 41%). Clinically significant myocardial infarction (MI), defined as troponin > 1.0 ng/dL, occurred in 13% of rFVIIa-treated and 6% of standard therapy-treated patients (p=0.52). Past history of CAD (p=0.0061) and baseline abnormal EKG (p=0.02) were independently associated with clinically significant MI following wICH while rFVIIa use was not. The incidences of DVT/PE (2% vs 9%; p=0.18) and ischemic stroke (2% vs 0%; p=0.38) were similar between two treatment groups. Recombinant FVIIa-treated patients had lower mean INR at 3 (p=0.0001) and 6 hours (p<0.0001) and received fewer units of FFP transfusion (3 vs 5; p=0.003).

CONCLUSIONS

Pre-existing thromboembolic risk factors as well as post-hemorrhage troponin elevation are prevalent in wICH patients. Clinically significant MI occurs in up to 13% of wICH patients. rFVIIa use was not associated with increased incidence of clinically significant MI or other venous or arterial thromboembolic events in this wICH cohort.

Net Clinical Benefit of Warfarin in Patients With Atrial Fibrillation

Background—

Known risk factors for bleeding during anticoagulant treatment are largely the same as those predicting thromboembolic events in patients with atrial fibrillation (AF). Our objective was to investigate how to maximize the likelihood of avoiding both stroke and bleeding.

Methods and Results—

All 182 678 subjects with atrial fibrillation in the Swedish Hospital Discharge Register were studied for an average of 1.5 years (260 000 patient-years at risk). Patients were stratified according to risk scores with the use of historic International Classification of Disease diagnostic codes in the register. Information about medication was obtained from the Swedish Drug Registry. Our primary end point was net benefit defined as number of avoided ischemic strokes with anticoagulation minus the number of excess intracranial bleedings with a weight of 1.5 to compensate for the generally more severe outcome with intracranial bleedings. The adjusted net clinical benefit favored anticoagulation for almost all atrial fibrillation patients. The exceptions were patients at very low risk of ischemic stroke with a CHA 2 DS 2 -VASc score of 0 and moderately elevated bleeding risk (−1.7%/y). The results were broadly similar with CHADS 2 , except for patients with very low embolic risk; the CHA 2 DS 2 -VASc was able to identify those patients (n=6205, 3.9% of all patients) who had no net clinical benefit or even some disadvantage from anticoagulant treatment.

Conclusions—

In almost all patients with atrial fibrillation, the risk of ischemic stroke without anticoagulant treatment is higher than the risk of intracranial bleeding with anticoagulant treatment. Analysis of the net benefit indicates that more patients may benefit from anticoagulant treatment.

Bleeding risk in randomized controlled trials comparing warfarin and aspirin: a systematic review and meta-analysis

BACKGROUND

Warfarin and aspirin (acetylsalicylic acid [ASA]) are the most commonly used anticoagulant and antiplatelet drugs in the treatment of cardiovascular disease.

OBJECTIVES

To provide a pooled estimate of the bleeding risk from randomized controlled trials (RCTs) comparing warfarin and ASA at the dose ranges recommended in evidence-based guidelines.

PATIENTS/METHODS

Ovid MEDLINE, Embase and the Cochrane Library, up to September 2011, were searched for RCTs comparing bleeding rates in adult patients randomized to warfarin, target International Normalized Ratio (INR) 2.0-3.5, and ASA, 50-650 mg daily, with at least 3 months of follow-up. Pooled odds ratios (ORs) and associated 95% confidence intervals (CIs) were calculated with the inverse variance method and the random effects model.

RESULTS

Four thousand four hundred and forty-two abstracts were screened, resulting in eight included studies for final analysis. A pooled estimate derived from the 2904 patients enrolled indicated a trend towards an increase in major bleeding risk in those randomized to warfarin (OR 1.27; 95% CI 0.83-1.94). The pooled OR for intracranial hemorrhage in patients treated with warfarin vs. ASA was 1.64 (95% CI 0.71-3.78), and that for extracranial major bleeding was 1.03 (95% CI 0.61-1.75). Minor bleeding, from a 1748-patient sample, was more common in warfarin patients (OR 1.50; 95% CI 1.13-2.00).

CONCLUSIONS

This meta-analysis failed to find a statistically significant difference in major bleeding between warfarin, target INR 2.0-3.5, and ASA, 50-650 mg daily. The trend towards increased bleeding with warfarin appears to be explained by an excess of intracranial bleeding in warfarin patients.

Iatrogenic cerebral venous sinus occlusion with flowable topical hemostatic matrix

Object

The use of commercially available topical hemostatic adjuncts has increased the safety profile of surgery as a whole. Cranial surgery has also benefited from the development of numerous agents designed to permit more rapid achievement of hemostasis. Flowable topical hemostatic agents applied via syringe injection are now commonly employed in many neurosurgical procedures, including cranial surgery. Intravascular use of these strongly thrombogenic agents is contraindicated, but in certain settings, inadvertent intravascular administration can occur, resulting in vascular occlusion, thrombosis, and potential dissemination. To date, there have no reports detailing the presence and incidence of this complication.

Methods

The authors conducted a retrospective review of all cranial surgeries performed at Presbyterian University Hospital by members of the University of Pittsburgh Medical Center's Department of Neurological Surgery between 2007 and 2009. Cases complicated by vascular occlusion due to inadvertent intravascular administration of flowable topical hemostatic matrix (FTHM) were identified and analyzed.

Results

Iatrogenic vascular occlusion induced by FTHM was identified in 5 (0.1%) of 3969 cranial surgery cases. None of these events occurred in 3318 supratentorial cases, whereas 5 cases of cerebral venous sinus occlusion occurred in 651 infratentorial cases (0.8%). The risk of accidental vessel occlusion was significantly associated with infratentorial surgery, and all events occurred in the transverse and/or sigmoid sinus. No episodes of inadvertent vascular occlusion occurred during endoscopic surgery. No cases of arterial occlusion were identified. Of the 5 patients with FTHM-related cerebral venous sinus occlusion, none developed long-term neurological sequelae referable to the event.

Conclusions

Inadvertent intravascular administration of FTHM is a rare complication associated with cranial surgery that occurs most commonly during infratentorial procedures around the transverse and/or sigmoid sinuses. Modifications in the choice of when to use an FTHM and the method of application may help prevent accidental venous sinus administration.

The acute management of intracerebral hemorrhage

PURPOSE OF REVIEW

Spontaneous intracerebral hemorrhage (ICH) is associated with high morbidity and mortality, providing substantial scope for improvements in outcome. This review will discuss recent developments and present consensus evidence for the management of ICH.

RECENT FINDINGS

Intracranial management strategies focus on preventing further bleeding and minimizing the risk of hematoma expansion and cerebral ischemia. Known coagulopathies should be corrected and oral anticoagulation reversed, but there is no evidence for the routine transfusion of platelets in patients taking aspirin or clopidogrel. Recombinant factor VIIa reduces hematoma expansion after ICH, but does not improve outcome and is associated with thromboembolic complications. The role and type of surgical interventions remain controversial. Early aggressive treatment, including meticulous control of blood pressure and other systemic physiological variables, improves outcome as does management in a specialized neurointensive care unit. Thromboembolic prophylaxis is routine but prophylactic antiepileptic drugs confer no benefit. Ongoing research seeks to define optimal blood pressure, glucose and temperature targets, the role and type of surgery, and potential neuroprotective strategies.

SUMMARY

Well organized, multimodal therapy optimizing intracranial and systemic physiological variables improves outcome after ICH. Recent guidelines provide a useful consensus evidence-based framework for the management of acute ICH.

Treatments for reversing warfarin anticoagulation in patients with acute intracranial hemorrhage: a structured literature review

Study objective

The acute management of patients on warfarin with spontaneous or traumatic intracranial hemorrhage continues to be debated in the medical literature. The objective of this paper was to conduct a structured review of the medical literature and summarize the advantages and risks of the available treatment options for reversing warfarin anticoagulation in patients who present to the emergency department with acute intracranial hemorrhage.

Methods

A structured literature search and review of articles relevant to intracranial hemorrhage and warfarin and treatment in the emergency department was performed. Databases for PubMed, CINAHL, and Cochrane EBM Reviews were electronically searched using keywords covering the concepts of anticoagulation drugs, intracranial hemorrhage (ICH), and treatment. The results generated by the search were limited to English- language articles and reviewed for relevance to our topic. The multiple database searches revealed 586 papers for review for possible inclusion. The final consensus of our comprehensive search strategy was a total of 23 original studies for inclusion in our review.

Results

Warfarin not only increases the risk of but also the severity of ICH by causing hematoma expansion. Prothrombin complex concentrate is statistically significantly faster at correcting the INR compared to fresh frozen plasma transfusions. Recombinant factor VIIa appears to rapidly reverse warfarin's effect on INR; however, this treatment is not FDA-approved and is associated with a 5% thromboembolic event rate. Slow intravenous dosing of vitamin K is recommended in patients with ICH. The 30-day risk for ischemic stroke after discontinuation of warfarin therapy was 3-5%. The risks of not reversing the anticoagulation in ICH generally outweigh the risk of thrombosis in the acute setting.

Conclusions

Increasing numbers of patients are on anticoagulation including warfarin. There is no uniform standard for reversing warfarin in intracranial hemorrhage. Intravenous vitamin K in addition to fresh frozen plasma or prothrombin complex concentrate is recommended be used to reverse warfarin-associated intracranial hemorrhage. No mortality benefit for one treatment regimen over another has been shown. Emergency physicians should know their hospital's available warfarin reversal options and be comfortable administering these treatments to critically ill patients.

The practical management of intracerebral hemorrhage associated with oral anticoagulant therapy

Oral anticoagulant-associated intracerebral hemorrhage is increasing 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 hemorrhage is represented by urgent reversal of coagulopathy, decreasing as quickly as possible the international normalized ratio to values ≤1·4, preferably ≤1·2, together with life support and surgical therapy, when indicated. Protocols for anticoagulant-associated intracerebral hemorrhage emphasize the immediate discontinuation of anticoagulant medication and the immediate intravenous administration of vitamin K1 (mean dose: 10-20 mg), and the use of prothrombin complex concentrates (variable doses calculated estimate circulating functional prothrombin complex) or fresh-frozen plasma (15-30 ml/kg) or recombinant activated factor VII (15-120 μg/kg). Because of cost and availability, there is limited randomized evidence comparing different reversal strategies that support a specific treatment regimen. In this paper, we emphasize the growing importance of anticoagulant-associated intracerebral hemorrhage and describe options for acute coagulopathy reversal in this setting. Additionally, emphasis is placed on understanding current consensus-based guidelines for coagulopathy reversal and the challenges of determining best evidence for these treatments. On the basis of the available knowledge, inappropriate adherence to current consensus-based guidelines for coagulopathy reversal may expose the physician to medico-legal implications.

Use of Prothrombin Complex Concentrate for Vitamin K Antagonist Reversal before Surgical Treatment of Intracranial Hemorrhage

Background:

Oral anticoagulant therapy (OAT) is used to prevent/treat thromboembolism. Major bleeding is common in patients on OAT; eg, warfarin increases intracranial hemorrhage (ICH) risk.

Case:

A 71-year-old male on warfarin (to reduce stroke risk) presented at Accident and Emergency Minor Injuries Unit with headache after reportedly sounding ‘drunk’. On triage, the patient appeared lucid and well. However, International Normalized Ratio (INR) was 4.1. Head computed tomography (CT) indicated a large right-sided subdural hematoma. Prothrombin complex concentrate (PCC; Beriplex^® P/N, CSL Behring) with vitamin K normalized the INR within minutes of administration. The patient underwent neurosurgery without complications, and was discharged after 5 days, with no residual neurological symptoms.

Conclusions:

ICH patients can present with no neurological signs. In OAT patients with headache, INR must be established; if ≥3.0, normalization of INR and head CT are essential. PCC is the best option to rapidly reverse anticoagulation and correct INR pre-surgery.

Recombinant factor VIIa and the patient with neurologic bleeding: separating fact from fiction

Notwithstanding its limited Food and Drug Administration-approved indications, rFVIIa has rapidly gained widespread use for the treatment of a variety of hemorrhagic conditions, including intracranial bleeding from spontaneous, traumatic, surgical, and coagulopathic causes. Although it appears that the drug only minimally increases the risk of thromboembolic events, its efficacy remains in question. The idea of finding a universal cure for hemorrhage in a medication bottle remains highly appealing, but enthusiasm for the concept is no replacement for evidence. Neuroscience nurses, who are the interface between patients and rFVIIa, need to balance hope and hype until the facts are all in.

The acute management of intracerebral hemorrhage: a clinical review

Intracerebral hemorrhage (ICH) is a devastating disease with high rates of mortality and morbidity. The major risk factors for ICH include chronic arterial hypertension and oral anticoagulation. After the initial hemorrhage, hematoma expansion and perihematoma edema result in secondary brain damage and worsened outcome. A rapid onset of focal neurological deficit with clinical signs of increased intracranial pressure is strongly suggestive of a diagnosis of ICH, although cranial imaging is required to differentiate it from ischemic stroke. ICH is a medical emergency and initial management should focus on urgent stabilization of cardiorespiratory variables and treatment of intracranial complications. More than 90% of patients present with acute hypertension, and there is some evidence that acute arterial blood pressure reduction is safe and associated with slowed hematoma growth and reduced risk of early neurological deterioration. However, early optimism that outcome might be improved by the early administration of recombinant factor VIIa (rFVIIa) has not been substantiated by a large phase III study. ICH is the most feared complication of warfarin anticoagulation, and the need to arrest intracranial bleeding outweighs all other considerations. Treatment options for warfarin reversal include vitamin K, fresh frozen plasma, prothrombin complex concentrates, and rFVIIa. There is no evidence to guide the specific management of antiplatelet therapy-related ICH. With the exceptions of placement of a ventricular drain in patients with hydrocephalus and evacuation of a large posterior fossa hematoma, the timing and nature of other neurosurgical interventions is also controversial. There is substantial evidence that management of patients with ICH in a specialist neurointensive care unit, where treatment is directed toward monitoring and managing cardiorespiratory variables and intracranial pressure, is associated with improved outcomes. Attention must be given to fluid and glycemic management, minimizing the risk of ventilator-acquired pneumonia, fever control, provision of enteral nutrition, and thromboembolic prophylaxis. There is an increasing awareness that aggressive management in the acute phase can translate into improved outcomes after ICH.