Treatment of warfarin-associated intracerebral hemorrhage: literature review and expert opinion

Association of lactate-to-albumin ratio with in-hospital and intensive care unit mortality in patients with intracerebral hemorrhage

Background

Intracerebral hemorrhage (ICH) is a severe stroke subtype with a high mortality rate; the lactate-to-albumin ratio (LAR) is a new biomarker for predicting clinical outcomes in patients with ICH. However, the relationship between LAR and mortality in patients with ICH treated in the intensive care unit (ICU) remains controversial. Therefore, in this study, we aimed to investigate the association between LAR and in-hospital and ICU mortality in patients with ICH.

Methods

Patients with ICH were selected from the Medical Information Mart for Intensive Care III (MIMIC-III) database; their clinical information, including baseline characteristics, vital signs, comorbidities, laboratory test results, and scoring systems, was extracted. Univariate and multivariate Cox proportional hazards analyses were used to investigate the association of LAR with in-hospital and ICU mortality. The maximum selection statistical method and subgroup analysis were used to investigate these relationships further. Kaplan-Meier (KM) analysis was used to draw survival curves.

Results

This study enrolled 237 patients with ICH whose lactate and albumin levels, with median values of 1.975 and 3.6 mg/dl, respectively, were measured within the first 24 h after ICU admission. LAR had an association with increased risk of in-hospital mortality [unadjusted hazards ratio (HR), 1.79; 95% confidence interval (CI), 1.32-2.42; p < 0.001] and ICU mortality (unadjusted HR, 1.88; 95% CI, 1.38-2.55; p < 0.001). A cut-off value of 0.963 mg/dl was used to classify patients into high LAR (≥0.963) and low LAR (<0.963) groups, and survival curves suggested that those two groups had significant survival differences (p = 0.0058 and 0.0048, respectively). Furthermore, the high LAR group with ICH had a significantly increased risk of in-hospital and ICU mortality compared to the low LAR group.

Conclusion

Our study suggests that a high LAR is associated with an increased risk of in-hospital and ICU mortality in patients with ICH. Thus, the LAR is a useful prognostic predictor of clinical outcomes in patients with ICH.

Tyrant’s End: Did Joseph Stalin Die From Warfarin Poisoning?

One of the most brutal dictators in humanity's history, Joseph Stalin forged the Soviet Union into a massive superpower, crushing the lives of millions of his own citizens along the way. His sudden death in March 1953 from a stroke took the world by surprise and led to a frantic power struggle within the ranks of the Soviet government. In recent years, researchers have proposed that Stalin's stroke was not natural and was potentially caused by one of his lieutenants poisoning him with warfarin or a similar anticoagulant. After examining the evidence, this article concludes that both Stalin's disease course and the properties of warfarin make it highly unlikely that he was deliberately assassinated.

Anticoagulation and bleeding in the cancer patient

Cancer patients have an increased risk of bleeding compared to non-cancer patients with anticoagulant therapy. A bleeding risk assessment before initiation of anticoagulation is recommended. Currently low molecular weight heparin (LMWH) and direct oral anticoagulants (DOACs) are the mainstays of treatment for cancer-associated venous thromboembolism (VTE). Since DOACs are administered orally, they offer some convenience and ease of administration; however, LMWH may be preferred in certain cancers. Given the prevalence of anticoagulant therapies in cancer patients, clinical providers must be able to recognize potentially critical bleeding sites and modalities to reverse major hemorrhage. Reversal agents or antidotes to bleeding may be required when bleeding is persistent or life-threatening. These include vitamin K, fresh frozen plasma (FFP), protamine, prothrombin complex concentrate (PCC) or andexanet alfa, and idarucizumab. Inferior vena cava (IVC) filter insertion can be also considered in those with major bleeding. Evidence for timing and need for re-initiation of anticoagulant therapy after a major bleeding remains sparse, but a multi-disciplinary approach and shared decision-making can be implemented in the interim.

Contribution of Various Types of Transfusion to Acute and Delayed Intracerebral Hemorrhage Injury

Intracerebral hemorrhage (ICH) is the second most prevalent type of stroke, after ischemic stroke, and has exceptionally high morbidity and mortality rates. After spontaneous ICH, one primary goal is to restrict hematoma expansion, and the second is to limit brain edema and secondary injury. Various types of transfusion therapies have been studied as treatment options to alleviate the adverse effects of ICH etiopathology. The objective of this work is to review transfusions with platelets, fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), and red blood cells (RBCs) in patients with ICH. Furthermore, tranexamic acid infusion studies have been included due to its connection to ICH and hematoma expansion. As stated, the first line of therapy is limiting bleeding in the brain and hematoma expansion. Platelet transfusion is used to promote recovery and mitigate brain damage, notably in patients with severe thrombocytopenia. Additionally, tranexamic acid infusion, FFP, and PCC transfusion have been shown to affect hematoma expansion rate and volume. Although there is limited available research, RBC transfusions have been shown to cause higher tissue oxygenation and lower mortality, notably after brain edema, increases in intracranial pressure, and hypoxia. However, these types of transfusion have varied results depending on the patient, hemostasis status/blood thinner, hemolysis, anemia, and complications, among other variables. Inconsistencies in published results on various transfusion therapies led us to review the data and discuss issues that need to be considered when establishing future guidelines for patients with ICH.

[Management of surgical complications following prolonged warfarin therapy in a general surgical hospital]

OBJECTIVE

To analyze an effectiveness of algorithm for complex treatment of patients with surgical complications of prolonged warfarin therapy in a general surgical hospital.

MATERIAL AND METHODS

The study included 138 patients with surgical complications of prolonged warfarin therapy. All patients received warfarin for at least 6 months (49.5% of patients - over 5 years). Warfarin therapy was indicated for deep vein thrombosis in 54 patients and various cardiac diseases in 84 patients. Examination included clinical and instrumental survey, laboratory tests and coagulation tests - thromboelastography (TEG) and thrombodynamics test (TT).

RESULTS

Recurrent VTEC occurred in 24 out of 138 patients, hemorrhagic complications - in 114 patients. Therapeutic management was applied in 111 patients, 27 ones underwent surgery (emergency treatment - 25 patients, after two days - 2 patients). Ten patients underwent endoscopic hemostasis, two patients - ultrasound-assisted percutaneous drainage of hematoma. Recurrent VTECs were caused by inadequate laboratory control and violations of warfarin therapy. Most of these patients underwent therapeutic management (only 3 patients required surgery for life-threatening flotation in great veins). Treatment of 114 patients with hemorrhagic complications of prolonged warfarin therapy depended on features of bleeding and severity of warfarin-induced coagulopathy. Depending on these factors, warfarin was discontinued and intravenous administration of vitamin K / FFP / prothrombin complex concentrate was applied. This approach ensured successful therapeutic measures in 90 patients of this group. Twenty-four patients underwent surgery after correction of hemostatic disorders. TT was characterized by high efficiency in analysis of thrombotic predisposition and prediction of the risk of VTEC. TEG was valuable for assessment of warfarin-induced coagulopathy and treatment of patients with hemorrhagic complications of prolonged warfarin therapy.

CONCLUSION

The developed clinical and diagnostic algorithm for management of hemorrhagic complications of prolonged warfarin therapy ensures positive clinical results even in a general surgical hospital.

Reversal of warfarin anticoagulation in geriatric traumatic brain injury due to ground-level falls

Background

The efficacy of prothrombin complex concentrate (PCC) compared with fresh frozen plasma (FFP) for reversal of oral anticoagulants has not been investigated in geriatric patients suffering intracranial hemorrhage (ICH) due to a ground-level fall (GLF).

Methods

Patients 65 years and older who were treated at Santa Barbara Cottage Hospital between January 2011 and March 2018 with ICH after a GLF while taking warfarin were reviewed. Patients were reversed with either FFP (n=25) or PCC (n=27) and patient outcomes were compared. Separate analyses were conducted for patients who received adjuvant vitamin K administration and those who did not.

Results

Mortality rates, hospital length of stay, intensive care unit admission and length of stay were similar for both FFP and PCC intervention. There was no difference in radiological progression of hemorrhage within the first 24 hours of admission (FFP: 36%, PCC: 43%, p=0.365). In patients who had international normalized ratio (INR) values measured prior to intervention, 81% (17 out of 21) of the PCC group reached an INR value below 1.5 within an 8-hour period, whereas only 29% (4 out of 14) of the FFP group did (p=0.002). Vitamin K was concomitantly given to 28% of the patients receiving FFP, and 81% of those patients receiving PCC. No significant differences in outcomes were found whether adjunctive vitamin K was administered or not, in either FFP or PCC group. However, when vitamin K was not administered, the PCC group had a higher rate of INR reversal (80% vs. 10% for FFP, p=0.006).

Conclusion

Administration of PCC is as effective in short-term outcomes as FFP in treating geriatric patients on warfarin sustaining an ICH after a GLF. INR reversal was more successful, significantly faster, and required lower infusion volumes in patients receiving PCC.

Level of evidence

Level III.

Anticoagulation Resumption After Intracerebral Hemorrhage

Purpose of review

Decision-making on resuming oral anticoagulant (OAC) after intracerebral hemorrhage (ICH) evokes significant debate among clinicians. Such patients have been excluded from randomized clinical trials. This review article provides a comprehensive summary of the evidence on anticoagulation resumption after ICH.

Recent findings

OAC resumption does not increase the risk of recurrent ICH and can also reduce the risk of all-cause mortality. OAC cessation exposes patients to a significantly higher risk of thromboembolism, which could be reduced by resumption. The optimal timing of anticoagulation resumption after ICH is still unknown. Both early (< 2 weeks) and late (> 4 weeks) resumption should be reached only after very careful assessment of risks for ICH recurrence and thromboembolism. The introduction of new oral anticoagulants and other interventions, such as left atrial appendage closure, has provided some patients with more alternatives.

Summary

Given the lack of high-quality evidence to guide clinical decision-making, clinicians must carefully balance the risks of thromboembolism and recurrent ICH in individual patients. We propose a management approach which would facilitate the decision-making process on whether anticoagulation is appropriate, as well as when and how to restart anticoagulation after ICH.

Anticoagulants

Anticoagulants are effective in the prevention and treatment of a variety of arterial and venous thrombotic disorders but are associated with an increased risk of serious bleeding complications. Based on well documented studies of patients using vitamin K antagonists the incidence of major bleeding is 0.5%/year and the incidence of intracranial bleeding is 0.2%/year, however, in real life practice this incidence may be even higher. Risk factors for bleeding are the intensity of anticoagulation, the management strategy to keep the anticoagulant effect in the desired range, and patient characteristics. Recently, a new generation of anticoagulants have been developed and is currently evaluated in clinical trials. Initial results show a similar or superior efficacy over conventional anticoagulant agents with a good safety profile. In case of serious bleeding complications in a patient who uses vitamin K antagonists, this anticoagulant treatment can be quickly reversed by administration of vitamin K or coagulation factor concentrates. For the newer anticoagulants, quick reversal strategies are more cumbersome, although some interventions, including prothrombin complex concentrates, show promising results in initial experimental studies.

Bleeding risk assessment and management in atrial fibrillation patients

In this executive summary of a Consensus Document from the European Heart Rhythm Association, endorsed by the European Society of Cardiology Working Group on Thrombosis, we comprehensively review the published evidence and propose a consensus on bleeding risk assessments in atrial fibrillation (AF) patients. The main aim of the document was to summarise ‘best practice’ in dealing with bleeding risk in AF patients when approaching antithrombotic therapy, by addressing the epidemiology and size of the problem, and review established bleeding risk factors. We also summarise definitions of bleeding in the published literature. Patient values and preferences balancing the risk of bleeding against thromboembolism as well as the prognostic implications of bleeding are reviewed. We also provide an overview of published bleeding risk stratification and bleeding risk schema. Brief discussion of special situations (e.g. periablation, peri-devices such as implantable cardioverter defibrillators [ICD] or pacemakers, presentation with acute coronary syndromes and/or requiring percutanous coronary interventions/stents and bridging therapy) is made, as well as a discussion of the prevention of bleeds and managing bleeding complications. Finally, this document puts forwards consensus statements that may help to define evidence gaps and assist in everyday clinical practice.

Safety of catheter ablation for atrial fibrillation in patients with intracranial hemorrhage

BACKGROUND

The safety of anticoagulation and radiofrequency catheter ablation (RFCA) in patients with atrial fibrillation (AF) and a history of intracranial hemorrhage (ICH) remains unclear. We investigated the risks and benefits of this approach in AF patients with a history of ICH.

PATIENTS AND METHODS

The ICH group included 45 AF patients with a history of ICH who underwent RFCA. Five of these patients were excluded because ICH occurred spontaneously after cerebral infarction. The control group included 80 individuals who presented for AF ablation and did not have a history of ICH. Two controls were matched for each study group patient in terms of sex, age (±2 years), type of AF, and procedure date.

RESULTS

Patients in the ICH group had higher CHADS₂ (1.7 ± 1.3 vs. 1.1 ± 1.2, p < 0.05), CHA₂DS₂-VASc (2.6 ± 1.7 vs. 1.9 ± 1.6, p < 0.05), and HAS-BLED scores (2.5 ± 1.0 vs. 1.1 ± 1.0, p < 0.001). All participants in both groups underwent successful RFCA. The incidence of ICH during follow-up (1 vs. 0, p = 0.333) was similar between the ICH and control groups. AF-free survival between the two groups was not significant (log-rank p = 0.283) within the first 3 months, but was significant (log-rank p = 0.011) within 48 months of RFCA. History of ICH was the only independent predictor of AF recurrence according to univariate Cox regression analysis.

CONCLUSION

In AF patients with a history of ICH, AF ablation with a standard anticoagulation strategy is safe and does not seem to be associated with an increased risk of hemorrhage.

[Direct oral anticoagulants and acute stroke : Insights into translational research studies]

In recent years a considerable number of translational research studies on intracerebral hemorrhage and ischemic stroke have been published, which are characterized by a particular proximity to practical clinical questions. Animal research has provided insights into the pathophysiological processes and therapy effects, which have so far only been insufficiently investigated in clinical studies. This includes the effectiveness of a rapid reversal of anticoagulation in cases of anticoagulation-associated intracerebral hemorrhage and the safety of thrombolytic treatment in ischemic stroke occurring during treatment with anticoagulants. With the approval of the direct oral anticoagulants these problems have become of particular contemporary relevance. Of course, results from experimental translational studies on stroke cannot be directly translated into clinical routine. Nevertheless, these investigations help to understand the underlying processes and mechanisms and provide proof of concept data for new treatment strategies. This review summarizes the most relevant results in this field of research with a particular focus on practical clinical questions.

Re-Initiation of Dabigatran and Direct Factor Xa Antagonists After a Major Bleed

Direct oral anticoagulants (DOACs) are a relatively recent addition to the oral anticoagulant armamentarium, and provide an alternative to the use of vitamin K antagonists such as warfarin. Regardless of the type of agent used, bleeding is the major complication of anticoagulant therapy. The decision to restart oral anticoagulation following a major hemorrhage in a previously anticoagulated patient is supported largely by retrospective studies rather than randomized clinical trials (mostly with vitamin K antagonists), and remains an issue of individualized clinical assessment: the patient's risk of thromboembolism must be balanced with the risk of recurrent major bleeding. This review provides guidance for clinicians regarding if and when a patient should be re-initiated on DOAC therapy following a major hemorrhage, based on the existing evidence.

Re-initiation of dabigatran and direct factor Xa antagonists after a major bleed

Direct oral anticoagulants (DOACs) are a relatively recent addition to the oral anticoagulant armamentarium, and provide an alternative to the use of vitamin K antagonists such as warfarin. Regardless of the type of agent used, bleeding is the major complication of anticoagulant therapy. The decision to restart oral anticoagulation following a major hemorrhage in a previously anticoagulated patient is supported largely by retrospective studies rather than randomized clinical trials (mostly with vitamin K antagonists), and remains an issue of individualized clinical assessment: the patient’s risk of thromboembolism must be balanced with the risk of recurrent major bleeding. This review provides guidance for clinicians regarding if and when a patient should be re-initiated on DOAC therapy following a major hemorrhage, based on the existing evidence.

Prophylactic Fresh Frozen Plasma Infusion is Ineffective in Reversing Warfarin Anticoagulation and Preventing Delayed Intracranial Hemorrhage After Falls

BACKGROUND

Elderly patients, with considerable fall risk, are increasingly anticoagulated to prevent thromboembolic disease. We hypothesized that a policy of prophylactic fresh frozen plasma (FFP) infusion in patients having falls would reverse vitamin K antagonists (VKAs) and that reversal would decrease delayed intracranial hemorrhage (ICH).

METHODS

A retrospective review of patients with trauma admitted to a level 2 community trauma center was performed from January 2010 until November 2012. Inclusion criteria were: ground level fall (GLF) with suspected head trauma, on VKA, an international normalized ratio (INR) of >1.5, and a negative head computed tomography (CT). Patients were transfused with FFP to a goal INR of <1.5 while observed. Patients were classified as reversed (REV) if the lowest INR achieved within 4 to 24 hours after initial INR was <1.5 or unreversed (NREV) if lowest INR achieved was >1.5. Chi-square and logistic regression were performed.

RESULTS

A total of 194 patients met the criteria. In all, 43 (22%) patients were able to be REV, and 151 (78%) patients remained NREV. Unreversed patients were male and younger (P < .05). There was no difference in mean FFP received. Unreversed patients had a higher initial INR of 3.0 compared to REV patients (2.5; P = .018). One patient developed a delayed ICH and belonged to the REV group.

CONCLUSION

The incidence of delayed hemorrhage was 0.5%. A strategy of prophylactic FFP infusion was ineffective in VKA reversal. We recommend against prophylactic infusion of FFP during a period of observation for patients on VKA with suspected head trauma and a negative initial CT.

Stroke prevention with rivaroxaban in higher-risk populations with atrial fibrillation

BACKGROUND

Atrial fibrillation (AF), the most common cardiac arrhythmia, is a major risk factor for stroke. Rivaroxaban, an oral factor Xa inhibitor, is approved for the prevention of stroke in patients with non-valvular AF. In the pivotal phase III trial ROCKET AF, rivaroxaban demonstrated non-inferiority compared with warfarin for reducing the risk of stroke or systemic embolism (SE) in patients with AF (intention-to-treat analysis), without an increased risk of major bleeding. Superior efficacy vs. warfarin was achieved while patients were on study medication. Other direct oral factor Xa inhibitors have completed phase III clinical trials in this indication. Compared with warfarin, apixaban (in the ARISTOTLE trial) and edoxaban (in the ENGAGE-AF trial) were shown to be superior or non-inferior, respectively, for reduction in stroke or SE risk in patients with AF. Baseline stroke risk, as indicated by CHADS2 scores, was lower in patients in the ARISTOTLE and ENGAGE-AF trials than in ROCKET AF.

OBJECTIVES

This review discusses the main findings from ROCKET AF, specifically examining recent subgroup analyses investigating rivaroxaban use across various patient types at high risk for adverse outcomes, including those with prior stroke or transient ischaemic attack, reduced renal function, prior myocardial infarction, peripheral artery disease, heart failure or patients aged ≥ 75 years and those resident in East Asia.

CONCLUSIONS

These subgroup analyses demonstrate that the treatment effect for rivaroxaban vs. warfarin is broadly consistent across a wide range of patient groups, with respect to both efficacy and safety.

[Glial fibrillary acidic protein in patients with symptoms of acute stroke: diagnostic marker of cerebral hemorrhage]

Glial fibrillary acidic protein (GFAP) is a highly brain-specific protein that is expressed in large quantities in astrocytes and has important functions in terms of maintaining and stabilizing the cytoskeleton. Acute intracerebral hemorrhage leads to an immediate mechanical destruction of astroglial cells with the subsequent release of GFAP into the extracellular space and the bloodstream. On the other hand, necrosis, cytolysis and GFAP release does not occur before 6-12 h after symptom onset in ischemic stroke. Thus, in the early hours after stroke increased GFAP values could indicate intracerebral hemorrhage. This review article describes the underlying pathophysiology of the test and guides the reader through the available data. Potential implications regarding the prehospital triage of acute stroke patients are discussed, including the possibility to initiate hyperacute treatment, such as blood pressure reduction in patients with intracerebral hemorrhage. Other areas of interest for a potential GFAP test include traumatic brain injury and malignant gliomas.

Evaluation of a fixed, weight-based dose of 3-factor prothrombin complex concentrate without adjunctive plasma following warfarin-associated intracranial hemorrhage

INTRODUCTION

Data regarding use of prothrombin complex concentrate (PCC) for international normalization ratio (INR) reversal in warfarin-associated intracranial hemorrhage (wICH) is variable with regards to dosages, adjunctive agents, and product choice. In 2012, we implemented a fixed, weight-based [30 IU/kg] dosing protocol of 3-factor PCC (3PCC) utilizing a rapid infusion rate and no requirement for fresh frozen plasma (FFP) following factor product administration. We aimed to evaluate the impact of this protocol on immediate and delayed INR reversal in patients admitted with wICH in the absence of FFP co-administration.

METHODS

We conducted a retrospective review of patients receiving 3PCC following wICH between January 1, 2012 and December 10, 2013. The primary objective was to determine the percentage of patients achieving goal INR (≤1.4) following 3PCC administration. Patients were excluded if their bleed was not intracranial in origin, received a dose outside of the specified protocol, or were given FFP as an adjunctive agent.

RESULTS

We included 35 patients with a mean presenting INR of 3.2 ± 1.3. Thirty patients (85.7%) achieved goal INR (≤1.4) following one dose of 3PCC. The mean INR after infusion of 3PCC was 1.3 ± 0.2. The median duration between 3PCC infusion and subsequent INR was 48.0 min (30-70.1 min). Vitamin K was utilized in 33 (94.3%) patients. No patient experienced a thromboembolic event within 7 days of 3PCC administration.

CONCLUSIONS

Fixed, weight-based dosing of 3PCC without adjunctive FFP resulted in high rates of complete INR reversal without significant adverse events.

Use of prothrombin complex concentrate in warfarin anticoagulation reversal in the emergency department: a quality improvement study of administration delays

BACKGROUND

Quick reversal of warfarin anticoagulation is important in life threatening bleeding. The aim of this study is to improve the administration delay when using Prothrombin Complex Concentrate (PCC) for the emergent reversal of warfarin anticoagulation in the emergency department.

METHODS

An audit and feedback quality improvement project was conducted in three phases: a retrospective audit phase, an analysis and feedback phase and prospective evaluation phase. The charts of all eligible patients in a single Emergency Department (ED) in Québec, Canada, who received PCC since the introduction of this product in 2009 until October 31, 2011, were retrospectively audited. The administration delay of PCC was calculated from the time of prescription to the time of administration. With the data, we determined where improvements could be attained, and jointly with all stakeholders in the ED and the blood bank, we created an action plan to ensure the timely administration of PCC. The action plan was then implemented and a six-month prospective evaluation study was conducted to determine any improvement.

RESULTS

Seventy-seven charts were reviewed in the retrospective chart audit. The mean administration delay was 73.6 minutes (STD [34.1]) with a median of 70.0 minutes (25-75% IQR [45.0-95.0]). We found that this delay was principally due to the following barriers: communication problems between the ED and the blood bank as well as delivery inefficiencies. An action plan that involved a flowchart to remind all clinicians how to order PCC and a new delivery method from the blood bank to the ED were developed. During the 6 months following the implementation of our action plan, 39 patients received PCC and the mean administration time decreased to 33.2 minutes (STD [14.2])(p < .0001) with a median of 30.0 minutes (25-75% IQR [24.3-38.8]).

CONCLUSION

By implementing an action plan comprising of a flowchart and a new delivery process, this audit and feedback quality improvement project reduced the administration time of PCC by more than half. Future studies to measure the impact of a similar audit and feedback process involving an action plan in other centers should be conducted before this type of quality improvement process is implemented on wider scale.

Comparison of a low, fixed dose and a high, weight-based dose of recombinant factor VIIa in the treatment of warfarin-associated intracranial hemorrhage

BACKGROUND

Recombinant activated Factor VII (rFVIIa) can be used for rapid INR normalization in patients with warfarin-associated intracranial hemorrhage (WA-ICH); however, the optimal dose to normalize INR has not been established.

METHODS

This is a retrospective review comparing two rFVIIa hospital protocols for WA-ICH [weight-based dose (80 mcg/kg) or fixed dose (2 mg)]. Primary endpoint was the percentage of patients with INR reversal (INR <1.3) at the next INR draw and the need for further doses of rFVIIa. Secondary endpoints included time to documented INR reversal and sustained INR normalization, morbidity, mortality, change in hematoma size, cost, and adverse drug reactions.

RESULTS

Twenty-nine patients were included in each group. The weight-based group received a mean dose of 78.9 ± 21 mcg/kg versus 26.6 ± 8 mcg/kg in the fixed dose group. More patients in the fixed dose protocol achieved documented INR reversal than those in the weight-based group (92.6 vs 72.4 %, p = 0.19). The weight-based group achieved INR normalization in 229.5 [102, 331] minutes versus 165 [83, 447] minutes in the fixed dose group (p=0.02). Time to sustained INR normalization was similar in both groups. Four patients in the fixed dose group received an additional dose of 1 mg per hospital protocol. With the exception of medication acquisition cost savings of about $4,300 per patient who received fixed dose protocol, all other endpoints were similar between groups.

CONCLUSIONS

A low, fixed dose of rFVIIa appears to be as effective as a high, weight-based dose in achieving INR normalization in patients with WA-ICH.

Antithrombotic medicines following intracerebral haemorrhage: where's the evidence?

The use of antithrombotic medicines in patients who have a history of intracerebral haemorrhage is widely perceived as being contraindicated. However, many patients with intracerebral haemorrhage may suffer from conditions for which antithrombotic medicines are indicated. Such scenarios represent a therapeutic dilemma whereby treating infers an increased risk of recurrent intracerebral haemorrhage, but not treating infers an increase of thrombotic complications. Despite the importance of this dilemma, there is very little guidance for prescribers. This perspective review considered previous systematic reviews that addressed this issue, together with recently published research findings from the Tayside Stroke Cohort. Systematic reviews of experimental and observational studies have concluded that there is a marked lack of data on which to judge the safety of oral anticoagulant agents following intracerebral haemorrhage. In addition, the limited data available regarding the use of antiplatelet medicines following intracerebral haemorrhage provide no evidence that they are harmful, and again further data are required. In the absence of such data, a decision analysis approach has been proposed. This considers the findings of other studies to infer the likely impact of using antithrombotic agents in patients with intracerebral haemorrhage. The success of this approach is contingent on the availability of reliable data that describe the rate of recurrent intracerebral haemorrhage; however, published data on this varies widely. There are a number of factors that conspire against researchers addressing this issue. The current paucity of evidence to guide prescribers faced with this therapeutic dilemma seems likely to remain for some time.

Management of acute stroke in patients taking novel oral anticoagulants

Each year, 1·0–2·0% of individuals with atrial fibrillation and 0·1–0·2% of those with venous thromboembolism who are receiving one of the novel oral anticoagulants (dabigatran, rivaroxaban, or apixaban) can be expected to experience an acute ischemic stroke. Additionally, 0·2–0·5% of individuals with atrial fibrillation who are receiving one of the novel oral anticoagulants can be expected to experience an intracranial hemorrhage. This opinion piece addresses the current literature and offers practical approaches to the management of patients receiving novel oral anticoagulants who present with an ischemic or hemorrhagic stroke. Specifically, we discuss the role of thrombolysis in anticoagulated patients with acute ischemic stroke and factors to consider concerning restarting anticoagulation after acute ischemic and hemorrhagic stroke.

Progressing haemorrhagic stroke: categories, causes, mechanisms and managements

Haemorrhagic stroke is a severe stroke subtype with high rates of morbidity and mortality. Although this condition has been recognised for a long time, the progressing haemorrhagic stroke has not received adequate attention, and it accounts for an even worse clinical outcome than the nonprogressing types of haemorrhagic stroke. In this review article, we categorised the progressing haemorrhagic stroke into acute progressing haemorrhagic stroke, subacute haemorrhagic stroke, and chronic progressing haemorrhagic stroke. Haematoma expansion, intraventricular haemorrhage, perihaematomal oedema, and inflammation, can all cause an acute progression of haemorrhagic stroke. Specific 'second peak' of perihaematomal oedema after intracerebral haemorrhage and 'tension haematoma' are the primary causes of subacute progression. For the chronic progressing haemorrhagic stroke, the occult vascular malformations, trauma, or radiologic brain surgeries can all cause a slowly expanding encapsulated haematoma. The mechanisms to each type of progressing haemorrhagic stroke is different, and the management of these three subtypes differs according to their causes and mechanisms. Conservative treatments are primarily considered in the acute progressing haemorrhagic stroke, whereas surgery is considered in the remaining two types.

Treatment of acute subdural hematoma

OPINION STATEMENT

Clinical presentation, neurologic condition, and imaging findings are the key components in establishing a treatment plan for acute SDH. Location and size of the SDH and presence of midline shift can rapidly be determined by computed tomography of the head. Immediate laboratory work up must include PT, PTT, INR, and platelet count. Presence of a coagulopathy or bleeding diathesis requires immediate reversal and treatment with the appropriate agent(s), in order to lessen the risk of hematoma expansion. Reversal protocols used are similar to those for intracerebral hemorrhage, with institutional variations. Immediate neurosurgical evaluation is sought in order to determine whether the SDH warrants surgical evacuation. Urgent or emergent surgical evacuation of a SDH is largely influenced by neurologic examination, imaging characteristics, and presence of mass effect or elevated intracranial pressure. Generally, evacuation of an acute SDH is recommended if the clot thickness exceeds 10 mm or the midline shift is greater than 5 mm, regardless of the neurologic condition. In patients with patients with an acute SDH with clot thickness <10 mm and midline shift <5 mm, specific considerations of neurologic findings and clinical circumstances will be of importance. In addition, consideration will be given as to whether an individual patient is likely to benefit from surgery. For an acute SDH, evacuation by craniotomy or craniectomy is preferred over burr holes based on available data. Postoperative care includes monitoring of resolution of pneumocephalus, mobilization and drain removal, and monitoring for signs of SDH reaccumulation. Medical considerations include seizure prophylaxis and management as well as management and resumption of antithrombotic and anticoagulant medication.

Update in intracerebral hemorrhage

Spontaneous, nontraumatic intracerebral hemorrhage (ICH) is defined as bleeding within the brain parenchyma. Intracranial hemorrhage includes bleeding within the cranial vault and encompasses ICH, subdural hematoma, epidural bleeds, and subarachnoid hemorrhage (SAH). This review will focus only on ICH. This stroke subtype accounts for about 10% of all strokes. The hematoma locations are deep or ganglionic, lobar, cerebellar, and brain stem in descending order of frequency. Intracerebral hemorrhage occurs twice as common as SAH and is equally as deadly. Risk factors for ICH include hypertension, cerebral amyloid angiopathy, advanced age, antithrombotic therapy and history of cerebrovascular disease. The clinical presentation is "stroke like" with sudden onset of focal neurological deficits. Noncontrast head computerized tomography (CT) scan is the standard diagnostic tool. However, newer neuroimaging techniques have improved the diagnostic yield in terms of underlying pathophysiology and may aid in prognosis. Intracerebral hemorrhage is a neurological emergency. Medical care begins with stabilization of airway, breathing function, and circulation (ABCs), followed by specific measures aimed to decrease secondary neurological damage and to prevent both medical and neurological complications. Reversal of coagulopathy when present is of the essence. Blood pressure management can be key and continues as an area of debate and ongoing research. Surgical evacuation of ICH is of unproven benefit though a subset of well-selected patients may have improved outcomes. Ventriculostomy and intracranial pressure (ICP) monitoring are interventions also used in this patient population. To date, hemostatic medications and neuroprotectants have failed to result in clinical improvement. A multidisciplinary approach is recommended, with participation of vascular neurology, vascular neurosurgery, critical care, and rehabilitation medicine as the main players.

Imaging of contrast medium extravasation in anticoagulation-associated intracerebral hemorrhage with dual-energy computed tomography

BACKGROUND AND PURPOSE

Contrast medium extravasation (CE) in intracerebral hemorrhage (ICH) is a marker of ongoing bleeding and a predictor of hematoma expansion. The aims of the study were to establish an ICH model in which CE can be quantified, characterized in ICH during warfarin and dabigatran anticoagulation, and to evaluate effects of prothrombin complex concentrates on CE in warfarin-associated ICH.

METHODS

CD1-mice were pretreated orally with warfarin, dabigatran, or vehicle. Prothrombin complex concentrates were administered in a subgroup of warfarin-treated mice. ICH was induced by stereotactic injection of collagenase VIIs into the right striatum. Contrast agent (350 μL Isovue 370 mg/mL) was injected intravenously after ICH induction (2-3.5 hours). Thirty minutes later, mice were euthanized, and CE was measured by quantifying the iodine content in the hematoma using dual-energy computed tomography.

RESULTS

The optimal time point for contrast injection was found to be 3 hours after ICH induction, allowing detection of both an increase and a decrease of CE using dual-energy computed tomography. CE was higher in the warfarin group compared with the controls (P=0.002). There was no significant difference in CE between dabigatran-treated mice and controls. CE was higher in the sham-treated warfarin group than in the prothrombin complex concentrates-treated warfarin group (P<0.001).

CONCLUSIONS

Dual-energy computed tomography allows quantifying CE, as a marker of ongoing bleeding, in a model of anticoagulation-associated ICH. Dabigatran induces less CE in ICH than warfarin and consequently reduces risks of hematoma expansion. This constitutes a potential safety advantage of dabigatran over warfarin. Nevertheless, in case of warfarin anticoagulation, prothrombin complex concentrates reduce this side effect.

Reversal of oral anticoagulation

Although the use of dabigatran and rivaroxaban are increasing, data on the reversal of their effects are limited. The lack of reliable monitoring methods and specific reversal agents renders treatment strategies empirical, and as a result, treatment consists mainly of supportive measures. Therefore, we performed a systematic search of the PubMed database to find studies and reviews pertaining to oral anticoagulation reversal strategies. This review discusses current anticoagulation reversal recommendations for the oral anticoagulants warfarin, dabigatran, and rivaroxaban for patients at a heightened risk of bleeding, actively bleeding, or those in need of preprocedural anticoagulation reversal. We highlight the literature that shaped these recommendations and provide directions for future research to address knowledge gaps. Although reliable recommendations are available for anticoagulation reversal in patients treated with warfarin, guidance on the reversal of dabigatran and rivaroxaban is varied and equivocal. Given the increasing use of the newer agents, focused research is needed to identify effective reversal strategies and develop and implement an accurate method (assay) to guide reversal of the newer agents. Determining patient-specific factors that influence the effectiveness of reversal treatments and comparing the effectiveness of various treatment strategies are pertinent areas for future anticoagulation reversal research.

Intracerebral haemorrhage associated with antithrombotic treatment: translational insights from experimental studies

Little is known about the pathophysiology of intracerebral haemorrhage that occurs during anticoagulant treatment. In observational studies, investigators have reported larger haematoma volumes and worse functional outcome in these patients than in those with intracerebral haemorrhage and a normal coagulation status. The need to prevent extensive haematoma enlargement by rapid reversal of the anticoagulation seems intuitive, although no evidence is available from randomised clinical trials. New oral anticoagulants, such as the direct thrombin inhibitor dabigatran and the factor Xa inhibitor rivaroxaban, have been approved recently; however, intracerebral haemorrhage during dabigatran or rivaroxaban anticoagulation has not been characterised, and whether anticoagulation reversal can be beneficial in this scenario is unknown. In a translational approach, new experimental models have been developed to study anticoagulation-associated intracerebral haemorrhage in more detail and to test treatment strategies. Vitamin k antagonists enlarge haematoma volumes and worsen functional outcome in animal models. Rapid reversal of anticoagulation in the experimental setting prevents prolonged haematoma expansion and improves outcome. The new oral anticoagulants increase intracerbral haemorrhage volumes less than does warfarin. Haemostatic approaches that have been used for vitamin k-associated intracerebral haemorrhage also seem to be effective in intracerebral haemorrhage associated with the new anticoagulants. These experimental studies are valuable for filling gaps in knowledge, but the results need careful translation into routine clinical practice.

A French multicenter randomised trial comparing two dose-regimens of prothrombin complex concentrates in urgent anticoagulation reversal

INTRODUCTION

Prothrombin complex concentrates (PCC) are haemostatic blood preparations indicated for urgent anticoagulation reversal, though the optimal dose for effective reversal is still under debate. The latest generation of PCCs include four coagulation factors, the so-called 4-factor PCC. The aim of this study was to compare the efficacy and safety of two doses, 25 and 40 IU/kg, of 4-factor PCC in vitamin K antagonist (VKA) associated intracranial haemorrhage.

METHODS

We performed a phase III, prospective, randomised, open-label study including patients with objectively diagnosed VKA-associated intracranial haemorrhage between November 2008 and April 2011 in 22 centres in France. Patients were randomised to receive 25 or 40 IU/kg of 4-factor PCC. The primary endpoint was the international normalised ratio (INR) 10 minutes after the end of 4-factor PCC infusion. Secondary endpoints were changes in coagulation factors, global clinical outcomes and incidence of adverse events (AEs).

RESULTS

A total of 59 patients were randomised: 29 in the 25 IU/kg and 30 in the 40 IU/kg group. Baseline demographics and clinical characteristics were comparable between the groups. The mean INR was significantly reduced to 1.2 - and ≤1.5 in all patients of both groups - 10 minutes after 4-factor PCC infusion. The INR in the 40 IU/kg group was significantly lower than in the 25 IU/kg group 10 minutes (P = 0.001), 1 hour (P = 0.001) and 3 hours (P = 0.02) after infusion. The 40 IU/kg dose was also effective in replacing coagulation factors such as PT (P = 0.038), FII (P = 0.001), FX (P <0.001), protein C (P = 0.002) and protein S (0.043), 10 minutes after infusion. However, no differences were found in haematoma volume or global clinical outcomes between the groups. Incidence of death and thrombotic events was similar between the groups.

CONCLUSIONS

Rapid infusion of both doses of 4-factor PCC achieved an INR of 1.5 or less in all patients with a lower INR observed in the 40 IU/kg group. No safety concerns were raised by the 40 IU/kg dose. Further trials are needed to evaluate the impact of the high dose of 4-factor PCC on functional outcomes and mortality.

TRIAL REGISTRATION

Eudra CT number 2007-000602-73.

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.

Intracranial hemorrhage

Intracranial hemorrhage refers to any bleeding within the intracranial vault, including the brain parenchyma and surrounding meningeal spaces. This article focuses on the acute diagnosis and management of primary nontraumatic intracerebral hemorrhage and subarachnoid hemorrhage in the emergency department.

Dengue hemorrhagic fever and severe thrombocytopenia in a patient on mandatory anticoagulation: balancing two life threatening conditions: a case report

Background

Managing a severe dengue infection is a challenge specially when complicated by other comorbidities. We report a patient with dengue haemorrhagic fever and spontaneous bleeding who required mandatory anticoagulation for a prosthetic mitral valve replacement. This is the first case report in published literature describing this therapeutic dilemma.

Case presentation

A fifty one year old Sri Lankan woman was diagnosed with dengue haemorrhagic fever with bleeding manifestations. During the critical phase of her illness, the platelet count dropped to 5,000/ɥl. She was also on warfarin 7 mg daily following a prosthetic mitral valve insertion. In managing the patient, the risk of bleeding had to be balanced against the risk of valve thrombosis without anticoagulation. Warfarin was withheld when the platelet count dropped to 100,000/ɥl and restarted when it recovered above 50,000/ɥl. The patient was off anticoagulation for 10 days.

Conclusions

We managed this patient with close observation and continuous risk benefit assessments of management decisions. However, experience with one patient cannot be generalized to others. Therefore, it is essential that clinicians share their experiences in managing such difficult patients.

Reversal of Vitamin K Antagonist (VKA) effect in patients with severe bleeding: a French multicenter observational study (Optiplex) assessing the use of Prothrombin Complex Concentrate (PCC) in current clinical practice

Introduction

Prothrombin Complex Concentrate (PCC) is a key treatment in the management of bleeding related to Vitamin K antagonists (VKA). This study aimed to evaluate prospectively PCC use in patients with VKA-related bleeding in view of the French guidelines published in 2008.

Methods

All consecutive patients with VKA-related bleeding treated with a 4-factor PCC (Octaplex^®) were selected in 33 French hospitals. Collected data included demographics, site and severity of bleeding, modalities of PCC administration, International Normalized Ratio (INR) values before and after PCC administration, outcomes and survival rate 15 days after infusion.

Results

Of 825 patients who received PCC between August 2008 and December 2010, 646 had severe bleeding. The main haemorrhage sites were intracranial (43.7%) and abdominal (24.3%). Mean INR before PCC was 4.4 ± 1.9; INR was unavailable in 12.5% of patients. The proportions of patients who received a PCC dose according to guidelines were 15.8% in patients with initial INR 2-2.5, 41.5% in patients with INR 2.5-3, 40.8% in patients with INR 3-3.5, 26.9% in patients with INR > 3.5, and 63.5% of patients with unknown INR. Vitamin K was administered in 84.7% of patients. The infused dose of PCC did not vary with initial INR; the mean dose was 25.3 ± 9.8 IU/Kg. Rates of controlled bleeding and target INR achievement were similar, regardless of whether or not patients were receiving PCC doses as per the guidelines. No differences in INR after PCC treatment were observed, regardless of whether or not vitamin K was administered. INR was first monitored after a mean time frame of 4.5 ± 5.6 hours post PCC. The overall survival rate at 15 days after PCC infusion was 75.4% (65.1% in patients with intracranial haemorrhage). A better prognosis was observed in patients reaching the target INR.

Conclusions

Severe bleeding related to VKA needs to be better managed, particularly regarding the PCC infused dose, INR monitoring and administration of vitamin K. A dose of 25 IU/kg PCC appears to be efficacious in achieving a target INR of 1.5. Further studies are required to assess whether adjusting PCC dose and/or better management of INR would improve outcomes.

Reversal of warfarin-induced hemorrhage in the emergency department

Warfarin, an oral vitamin K antagonist, is used to prevent arterial and venous thromboembolism in patients suffering from a multitude of diseases. In 2004, 31 million warfarin prescriptions were dispensed in the United States. Warfarin inhibits the activation of the vitamin K-dependent clotting factors (Factors II, VII, IX, and X) and regulatory proteins (proteins C, S, and Z). It is one of the leading drugs implicated in emergency room visits for adverse drug reactions. Annually the frequency of bleeding complications associated with overanticoagulation is 15% to 20%, with fatal bleeds measuring as high as 1% to 3%. The most effective method of warfarin reversal involves the use of Four Factor Prothrombin Complex Concentrate (PCC), which is widely used throughout Europe but is unavailable in the United States. The current therapies available to emergency room physicians in the United States are fresh frozen plasma, recombinant Factor VIIa (rFVIIa), Factor Eight Inhibitory Bypassing Activity, or Three Factor PCC concomitantly administered with vitamin K. We review the advantages and disadvantages of these therapies and recommend Three Factor PCC with small doses of rFVIIa and with vitamin K in life-threatening situations if Four Factor PCC is unavailable.

Emergency management of bleeding associated with old and new oral anticoagulants

As major prescribers of oral anticoagulants, cardiologists must be familiar with strategies to manage bleeding, the principal complication associated with all anticoagulants, and to reverse anticoagulant effects in acute-care settings. The purpose of this manuscript is to review currently available information regarding dabigatran and rivaroxaban, the 2 novel oral anticoagulants approved to date in the United States. Further, we suggest reasonable interventions for the clinician faced with a patient who suffers a major bleeding event while receiving one of these agents. Data sources were peer-reviewed publications, US Food and Drug Administration documents in the public domain, and approved US prescribing information for dabigatran (Pradaxa) and rivaroxaban (Xarelto). Strategies for management of bleeding and reversal of anticoagulant effects from warfarin include vitamin K, fresh frozen plasma, and prothrombin complex concentrates. For rivaroxaban and dabigatran, appropriate therapies include support and observation, which are likely to be effective for the majority of patients because of the short half-lives of these agents. In severe life-threatening hemorrhage, clotting-factor substitutes may be appropriate in certain situations. Validated protocols specific to each agent remain to be developed.

Management dilemmas in patients with mechanical heart valves and warfarin-induced major bleeding

Management of warfarin-induced major bleeding in patients with mechanical heart valves is challenging. There is vast controversy and confusion in the type of treatment required to reverse anticoagulation and stop bleeding as well as the ideal time to restart warfarin therapy safely without recurrence of bleeding and/or thromboembolism. Presently, the treatments available to reverse warfarin-induced bleeding are vitamin K, fresh frozen plasma, prothrombin complex concentrates and recombinant activated factor VIIa. Currently, vitamin K and fresh frozen plasma are the recommended treatments in patients with mechanical heart valves and warfarin-induced major bleeding. The safe use of prothrombin complex concentrates and recombinant activated factor VIIa in patients with mechanical heart valves is controversial and needs well-designed clinical studies. With regard to restarting anticoagulation in patients with warfarin-induced major bleeding and mechanical heart valves, the safe period varies from 7-14 d after the onset of bleeding for patients with intracranial bleed and 48-72 h for patients with extra-cranial bleed. In this review article, we present relevant literature about these controversies and suggest recommendations for management of patients with warfarin-induced bleeding and a mechanical heart valve. Furthermore, there is an urgent need for separate specific guidelines from major associations/ professional societies with regard to mechanical heart valves and warfarin-induced bleeding.

Incidence, clinical impact and risk of bleeding during oral anticoagulation therapy

Bleeding is the most important complication of oral anticoagulation (OAC) with vitamin K-antagonists. Whilst bleeding is unavoidably related to OAC, it may have a great impact on the prognosis of treated subjects by leading to discontinuation of treatment, permanent disability or death. The yearly incidence of bleeding during OAC is 2%-5% for major bleeding, 0.5%-1% for fatal bleeding, and 0.2%-0.4% for intracranial bleeding. While OAC interruption and/or antagonism, as well as administration of coagulation factors, represent the necessary measures for the management of bleeding, proper stratification of the individual risk of bleeding prior to start OAC is of paramount importance. Several factors, including advanced age, female gender, poor control and higher intensity of OAC, associated diseases and medications, as well as genetic factors, have been proven to be associated with an increased risk of bleeding. Most of these factors have been included in the development of bleeding prediction scores, which should now be used by clinicians when prescribing and monitoring OAC. Owing to the many limitations of OAC, including a narrow therapeutic window, cumbersome management, and wide inter- and intra-individual variability, novel oral anticoagulants, such as factor Xa inhibitors and direct thrombin inhibitors, have been recently developed. These agents can be given in fixed doses, have little interaction with foods and drugs, and do not require regular monitoring of anticoagulation. While the novel oral anticoagulants show promise for effective thromboprophylaxis in atrial fibrillation and venous thromboembolism, definitive data on their safety and efficacy are awaited.

Experimental intracerebral hemorrhage: avoiding pitfalls in translational research

Intracerebral hemorrhage (ICH) has the highest mortality of all stroke subtypes, yet treatments are mainly limited to supportive management, and surgery remains controversial. Despite significant advances in our understanding of ICH pathophysiology, we still lack preclinical models that accurately replicate the underlying mechanisms of injury. Current experimental ICH models (including autologous blood and collagenase injection) simulate different aspects of ICH-mediated injury but lack some features of the clinical condition. Newly developed models, notably hypertension- and oral anticoagulant therapy-associated ICH models, offer added benefits but further study is needed to fully validate them. Here, we describe and discuss current approaches to experimental ICH, with suggestions for changes in how this condition is studied in the laboratory. Although advances in imaging over the past few decades have allowed greater insight into clinical ICH, there remains an important role for experimental models in furthering our understanding of the basic pathophysiologic processes underlying ICH, provided limitations of animal models are borne in mind. Owing to differences in existing models and the failed translation of benefits in experimental ICH to clinical practice, putative neuroprotectants should be trialed in multiple models using both histological and functional outcomes until a more accurate model of ICH is developed.

Recombinant activated coagulation factor VII and prothrombin complex concentrates are equally effective in reducing hematoma volume in experimental warfarin-associated intracerebral hemorrhage

BACKGROUND AND PURPOSE

Based on an experimental model of warfarin-associated intracerebral hemorrhage, we investigated whether the rapid reversal of anticoagulation using prothrombin complex concentrates (PCC) or recombinant activated coagulation factor VII (rFVIIa) reduces hematoma volume.

METHODS

Mice were orally pretreated with warfarin (2 mg/kg). Intracerebral hemorrhage was induced by collagenase injection into the right striatum. Forty-five minutes later, PCC (100 IE/kg), rFVIIa (1 mg/kg), or an equal volume of saline was administered intravenously. Hematoma volume after 24 hours was quantified using a photometric hemoglobin assay.

RESULTS

International normalized ratio was 4.3±0.4 in saline-treated mice, 0.9±0.1 in rFVIIa mice, and 1.4±0.2 in PCC mice. Intracerebral hemorrhage volume was 29.0±19.7 μL in the saline group (n=7), 8.6±4.3 μL in the rFVIIa group (n=6), and 6.1±1.8 μL in the PCC group (n=7; analysis of variance between-group differences P=0.004; post hoc rFVIIa versus saline P=0.021; PCC versus saline P=0.007). No significant difference was found between PCC- and rFVIIa-treated animals.

CONCLUSIONS

Our results suggest that PCC and rFVIIa are equally effective in restoring coagulation and preventing excessive hematoma growth in acute warfarin-associated intracerebral hemorrhage.

Anticoagulation with the oral direct thrombin inhibitor dabigatran does not enlarge hematoma volume in experimental intracerebral hemorrhage

BACKGROUND

The direct thrombin inhibitor dabigatran etexilate (DE) may constitute a future replacement of vitamin K antagonists for long-term anticoagulation. Whereas warfarin pretreatment is associated with greater hematoma expansion after intracerebral hemorrhage (ICH), it remains unclear what effect direct thrombin inhibitors would have. Using different experimental models of ICH, this study compared hematoma volume among DE-treated mice, warfarin-treated mice, and controls.

METHODS AND RESULTS

CD-1 mice were fed with DE or warfarin. Sham-treated mice served as controls. At the time point of ICH induction, DE mice revealed an increased activated partial thromboplastin time compared with controls (mean±SD 46.1 ± 5.0 versus 18.0 ± 1.5 seconds; P=0.022), whereas warfarin pretreatment resulted in a prothrombin time prolongation (51.4 ± 17.9 versus 10.4 ± 0.3 seconds; P<0.001). Twenty-four hours after collagenase-induced ICH formation, hematoma volume was 3.8 ± 2.9 μL in controls, 4.8 ± 2.7 μL in DE mice, and 14.5 ± 11.8 μL in warfarin mice (n=16; Welch ANOVA between-group differences P=0.007; posthoc analysis with the Dunnett method: DE versus controls, P=0.899; warfarin versus controls, P<0.001; DE versus warfarin, P=0.001). In addition, a model of laser-induced cerebral microhemorrhage was applied, and the distances that red blood cells and blood plasma were pushed into the brain were quantified. Warfarin mice showed enlarged red blood cell and blood plasma diameters compared to controls, but no difference was found between DE mice and controls.

CONCLUSIONS

In contrast with warfarin, pretreatment with DE did not increase hematoma volume in 2 different experimental models of ICH. In terms of safety, this observation may represent a potential advantage of anticoagulation with DE over warfarin.

Emergency neurological care of strokes and bleeds

Ischemic stroke and brain hemorrhage are common and challenging problems faced by emergency physicians. In this article, important details in the diagnosis and clinical management of these neurological emergencies are presented with the following goals: 1) To provide a more comprehensive understanding of the approach to the identification and management of patients who have sustained ischemic and hemorrhagic strokes; 2) to explain the importance and application of commonly used national stroke scoring and outcome scales; 3) to improve the ability to recognize important aspects in the approach and comprehensive treatment of ruptured and unruptured intracranial aneurysms; and 4) to demonstrate the difficulties in the neurological, neurosurgical, and endovascular treatment of these catastrophic diseases.

Treatment of acute intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a neurologic emergency associated with regular, early, ongoing hemorrhage, progressive clinical deterioration, severe deficits, and high mortality. Hence, it requires prompt recognition, diagnosis, and management. Initial monitoring and management of patients with ICH should occur in an intensive care unit. The overall approach to treatment mandates using therapies to stop or slow the initial bleeding acutely, removing blood from the parenchyma or ventricles (in eligible patients) to prevent secondary brain injury, addressing raised intracranial pressure, and providing good, comprehensive supportive care, including management of airways, oxygenation, blood pressure, circulation, glucose level, fever, and nutrition, as well as deep venous thrombosis prophylaxis.

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.

Should anticoagulation be resumed after intracerebral hemorrhage?

Intracerebral hemorrhage (ICH) is the most feared and the most deadly complication of oral anticoagulant therapy, eg, with warfarin (Coumadin). After such an event, clinicians wonder whether their patients should resume anticoagulant therapy. The authors review the management of anticoagulation during and after anticoagulation-associated ICH.

Fast point-of-care coagulometer guided reversal of oral anticoagulation at the bedside hastens management of acute subdural hemorrhage

BACKGROUND

Emergency reversal of the international normalized ratio (INR) in patients who develop nontraumatic subdural hemorrhage (SDH) due to oral anticoagulants (OAC) represents a primary treatment strategy but it is difficult to predict the amount of prothrombin complex concentrate (PCC) needed for reversal treatment. Moreover, repeated INR testings in central laboratories (CL) are time consuming. The usefulness of point-of-care INR coagulometers (POC) to test the success of INR reversal in OAC-SDH has not yet been investigated.

METHODS

Prospectively, INR reversal was performed by administering PCC to patients suffering from acute SDH-OAC using a predefined dosing schedule. Accuracy and time gained by using POC were assessed and compared with CL measurements.

RESULTS

A total of 10 patients were treated according to the protocol (male: 5). Bland-Altman analysis between POC and CL revealed a mean INR deviation of 0.013 for initial INR values and of 0.081 during reversal treatment. Using POC, the median initial net time gain (accounting for clinical examination and CT) for the start of PCC was 21 min. Median total time for POC-documented reversal was 27 min, as compared to 70 min for CL. The shortest interval between head CT and start of emergency SDH evacuation surgery was 37 min. By employing stepwise POC-guided reversal of the anticoagulatory effect of OAC, the calculated PCC dose could be reduced by 25% in the median.

CONCLUSIONS

Using POC to measure INR values and patient-adapted PCC administration is a fast and economic method to reverse anticoagulation in patients with acute OAC-SDH.

Emergency reversal of anticoagulation with a three-factor prothrombin complex concentrate in patients with intracranial haemorrhage

BACKGROUND

Intracranial haemorrhage is a serious and potentially fatal complication of oral anticoagulant therapy. Prothrombin complex concentrates can substantially shorten the time needed to reverse the effects of oral anticoagulants. The aim of this study was to determine the efficacy and safety of a prothrombin complex concentrate for rapid reversal of oral anticoagulant therapy in patients with intracranial haemorrhage.

METHODS

Patients receiving oral anticoagulant therapy and suffering from acute intracranial haemorrhage were eligible for this prospective cohort study if their International Normalised Ratio (INR) was higher than or equal to 2.0. The prothrombin complex concentrate was infused at doses of 35-50 IU/kg, stratified according to the initial INR.

RESULTS

Forty-six patients (25 males; mean age: 75 years; range 38-92 years) were enrolled. The median INR at presentation was 3.5 (range, 2-9). At 30 minutes after administration of the prothrombin complex concentrate, the median INR was 1.3 (range, 0.9-3), and the INR then declined to less than or equal to 1.5 in 75% of patients. The benefit of the prothrombin complex concentrate was maintained for a long time, since the median INR remained lower than or equal to 1.5 (median, 1.16; range, 0.9-2.2) at 96% of all post-infusion time-points up to 96 hours. No thrombotic complications or significant adverse events were observed during hospitalisation; six patients (13%) died, but none of these deaths was judged to be related to administration of the prothrombin complex concentrate.

CONCLUSIONS

Prothrombin complex concentrates are an effective, rapid and safe treatment for the urgent reversal of oral anticoagulation in patients with intracranial haemorrhage. Broader use of prothrombin complex concentrates in this clinical setting appears to be appropriate.

The persisting burden of intracerebral haemorrhage: can effective treatments be found?

Colin Josephson, Rustam Al-Shahi Salman, and colleagues discuss the effectiveness of treatments for intracerebral haemorrhage.

Astroglial proteins as diagnostic markers of acute intracerebral hemorrhage-pathophysiological background and clinical findings

The time span from symptom onset to treatment initiation remains a critical variable determining the efficacy of thrombolysis in acute ischemic stroke. To date, performing a brain scan is indispensable prior to therapy in order to differentiate between patients with ischemic stroke and those with intracerebral hemorrhage (ICH). This causes substantial treatment delay, as thrombolysis cannot be applied prior to hospital admission at much earlier time points. Recently, brain-specific astroglial proteins (i.e., glial fibrillary acidic protein (GFAP), S100B) were identified to be released rapidly from the cytoplasm of destroyed cells in case of acute ICH. Elevated serum concentrations were found within the first 6 h after ICH onset. In contrast, in ischemic stroke, these proteins are released with delay, mirroring the more gradual occurrence of necrotic cell death and blood brain barrier disruption. S100B and GFAP may qualify as candidate serum biomarkers which are able to differentiate between ischemic stroke and ICH in the emergency phase of stroke. This minireview enlightens the pathophysiological background of this finding and provides an overview on currently available clinical data.