Prothrombin complex concentrates to reverse warfarin-induced coagulopathy in patients with intracranial bleeding

Practical Guide for Anticoagulant and Antiplatelet Reversal in Clinical Practice

In recent years, anticoagulant and antiplatelet use have increased over the past years for the prevention and treatment of several cardiovascular conditions. Due to the rising use of antithrombotic medications and the complexity of specific clinical cases requiring such therapies, bleeding remains the primary concern among patients using antithrombotics. Direct oral anticoagulants (DOACs) include rivaroxaban, apixaban, edoxaban, and betrixaban. Direct thrombin inhibitors (DTIs) include argatroban, bivalirudin, and dabigatran. DOACs are associated with lower rates of fatal, life-threatening, and significant bleeding risks compared to those of warfarin. The immediate reversal of these agents can be indicated in an emergency setting. Antithrombotic reversal recommendations are still in development. Vitamin K and prothrombin complex concentrate (PCCs) can be used for warfarin reversal. Andexanet alfa and idarucizumab are specific reversal agents for DOACs and DTIs, respectively. Protamine sulfate is the solely approved reversal agent for unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH). However, there are no specific reversal agents for antiplatelets. This article aims to provide a practical guide for clinicians regarding the reversal of anticoagulants and antiplatelets in clinical practice based on the most recent studies.

Presumptive Haematomyelia Secondary to Warfarin Toxicosis in a Dog

A 3-year-old male entire Boxer was presented for a 6-day history of progressive symmetric nonambulatory tetraparesis with diffuse spinal hyperesthesia. Eight days prior to admission, the dog ingested warfarin accidentally, exhibiting systemic clinical signs of intoxication 2 days later. Upon referral, the dog was nonambulatory with paretic thoracic limbs and plegia with absent nociception on pelvic limbs, spinal reflexes were decreased to absent in all four limbs, and urinary and faecal incontinence were noticed. Magnetic resonance imaging (MRI) of the cervical, thoracic, and lumbar regions of the vertebral column revealed intramedullary lesions extending from the first cervical segments to the conus medullaris consistent with extensive intramedullary haemorrhages. Despite management with vitamin K1 and physiotherapy, 6 weeks later, improvement was limited to thoracic limb motor function, and euthanasia was elected. This case reports an extensive presumptive haematomyelia with severe neurological deficits suspected to be secondary to warfarin intoxication in a dog.

Safety and efficacy of prothrombin complex concentrate (PCC) for anticoagulation reversal in patients undergoing urgent neurosurgical procedures: a systematic review and metaanalysis

Anticoagulant therapy poses a significant risk for patients undergoing emergency neurosurgery procedures, necessitating reversal with prothrombin complex concentrate (PCC) or fresh frozen plasma (FFP). Data on PCC efficacy lack consistency in this setting. This systematic review and metaanalysis aimed to evaluate efficacy and safety of PCC for anticoagulation reversal in the context of urgent neurosurgery. Articles from PubMed, Embase, and Cochrane databases were screened according to the PRISMA checklist. Adult patients receiving anticoagulation reversal with PCC for emergency neurosurgical procedures were included. When available, patients who received FFP were included as a comparison group. Pooled estimates of observational studies were calculated for efficacy and safety outcomes via random-effects modeling. Initial search returned 4505 articles, of which 15 studies met the inclusion criteria. Anticoagulants used included warfarin (83%), rivaroxaban (6.8%), phenprocoumon (6.1%), apixaban (2.2%), and dabigatran (1.5%). The mean International Normalized Ratio (INR) prePCC administration ranged from 2.3 to 11.7, while postPCC administration from 1.1 to 1.4. All-cause mortality at 30 days was 27% (95%CI 21, 34%; I² = 44.6%; p-heterogeneity = 0.03) and incidence of thromboembolic events was 6.00% among patients treated with PCC (95%CI 4.00, 10.0%; I² = 0%; p-heterogeneity = 0.83). Results comparing PCC and FFP demonstrated no statistically significant differences in INR reversal, mortality, or incidence of thromboembolic events. This metaanalysis demonstrated adequate safety and efficacy for PCC in the reversal of anticoagulation for urgent neurosurgical procedures. There was no significant difference between PCC and FFP, though further trials would be useful in demonstrating the safety and efficacy of PCC in this setting.

A Retrospective Comparison of 3-Factor Prothrombin Complex Concentrate Products for Warfarin Reversal

Background and Purpose

Current guidelines suggest that 3-factor prothrombin complex concentrate is a possible alternative to 4-factor products for the emergent reversal of bleeding secondary to warfarin. While multiple observational studies have evaluated various forms of 3-factor prothrombin complex concentrate individually, no study has compared the efficacy of the 2 products. The purpose of this study is to compare the efficacy and safety of Bebulin™ and Profilnine™ for the emergent reversal of warfarin-associated major bleeding.

Methods

We conducted a retrospective cohort study of patients receiving both Bebulin™ and Profilnine™ at an urban, academic medical center with comprehensive stroke center designation and a neurosurgical center of excellence. All patients were treated at a single center that utilized a fixed, weight-based dosing protocol. The primary outcome was the percentage of patients in each group achieving a goal international normalization ratio of 1.4 or less.

Results

There was a significant difference in goal international normalization ratio achieved favoring Bebulin™ (85.5% vs 27.3%; P < .001) over Profilnine™. Median dose per kilogram of actual body weight was the same between the groups. When we assessed results by baseline™ international normalization ratio subgroup, more patients in the Bebulin™ group achieved goal when baseline values were 6 or less. No thrombotic events were documented in either group.

Conclusions

We found that patients treated with Bebulin™ experienced significantly higher rates of successful international normalization ratio reversal when compared to those who received Profilnine™. Further research is needed to determine the comparative efficacy between the 2 agents.

Collaborative Management Strategies for Drug Shortages in Neurocritical Care

Drug shortages have become all too familiar in the health care environment, with over 200 drugs currently on shortage. In the wake of Hurricane Maria in September 2017, hospitals across the USA had to quickly and creatively adjust medication preparation and administration techniques in light of decreased availability of intravenous (IV) bags used for compounding a vast amount of medications. Amino acid preparations, essential for compounding parenteral nutrition, were also directly impacted by the hurricane. Upon realization of the impending drug shortages, hospitals resorted to alternative methods of drug administration, such as IV push routes, formulary substitutions, or alternative drug therapies in hopes of preserving the small supply of IV bags available and prioritizing them for them most critical needs. In some cases, alternative drug therapies were required, which increased the risk of medication errors due to the use of less-familiar treatment options. Clinical pharmacists rounding with medical teams provided essential, patient-specific drug regimen alternatives to help preserve a dwindling supply while ensuring use in the most critical cases. Drug shortages also frequently occur in the setting of manufacturing delays or discontinuation and drug recalls, with potential to negatively impact patient care. The seriousness of the drug shortage crisis reached public attention by December 2017, when political and pharmacy organizations called for response to the national drug shortage crisis. In this article, we review institutional mitigation strategies in response to drug shortages and discuss downstream effects of these shortages, focusing on medications commonly prescribed in neurocritical care patients.

Toll-like receptor-4 pathway as a possible molecular mechanism for brain injuries after subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is known as an acute catastrophic neurological disease that continues to be a serious and significant health problem worldwide. The mechanisms contributing to brain injury after SAH remain unclear despite decades of study focusing on early brain injury (EBI) and delayed brain injury (DBI). Neuroinflammation is a well-recognized consequence of SAH and may be responsible for EBI, cerebral vasospasm, and DBI. Toll-like receptors (TLRs) play a crucial role in the inflammatory response by recognizing damage-associated molecular patterns derived from the SAH. TLR4 is the most studied Toll-like receptor and is widely expressed in the central nervous system (CNS). It can be activated by the extravasated blood components in myeloid differentiation primary response-88/Toll/interleukin-1 receptor-domain-containing adapter-inducing interferon-β (MyD88/TRIF)-dependent pathway after SAH. Transcription factors, such as nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK) and interferon regulatory factor (IRF), that regulate the expression of proinflammatory cytokine genes are initiated by the activation of TLR4, which cause the brain damage after SAH. TLR4 may therefore be a useful therapeutic target for overcoming EBI and DBI in post-SAH neuroinflammation, thereby improving SAH outcome. In the present review, we summarized recent findings from basic and clinical studies of SAH, with a primary focus on the biological characteristics and functions of TLR4 and discussed the mechanisms associated with TLR4 signaling pathway in EBI and DBI following SAH.

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.

A Retrospective Propensity Score-Matched Early Thromboembolic Event Analysis of Prothrombin Complex Concentrate vs Fresh Frozen Plasma for Warfarin Reversal Prior to Emergency Neurosurgical Procedures

BACKGROUND

Reversal of therapeutic anticoagulation prior to emergency neurosurgical procedures is required in the setting of intracranial hemorrhage. Multifactor prothrombin complex concentrate (PCC) promises rapid efficacy but may increase the probability of thrombotic complications compared to fresh frozen plasma (FFP).

OBJECTIVE

To compare the rate of thrombotic complications in patients treated with PCC or FFP to reverse therapeutic anticoagulation prior to emergency neurosurgical procedures in the setting of intracranial hemorrhage at a level I trauma center.

METHODS

Sixty-three consecutive patients on warfarin therapy presenting with intracranial hemorrhage who received anticoagulation reversal prior to emergency neurosurgical procedures were retrospectively identified between 2007 and 2016. They were divided into 2 cohorts based on reversal agent, either PCC (n = 28) or FFP (n = 35). The thrombotic complications rates within 72 h of reversal were compared using the χ2 test. A multivariate propensity score matching analysis was used to limit the threat to interval validity from selection bias arising from differences in demographics, laboratory values, history, and clinical status.

RESULTS

Thrombotic complications were uncommon in this neurosurgical population, occurring in 1.59% (1/63) of treated patients. There was no significant difference in the thrombotic complication rate between groups, 3.57% (1/28; PCC group) vs 0% (0/35; FFP group). Propensity score matching analysis validated this finding after controlling for any selection bias.

CONCLUSION

In this limited sample, thrombotic complication rates were similar between use of PCC and FFP for anticoagulation reversal in the management of intracranial hemorrhage prior to emergency neurosurgical procedures.

Management of Severe Bleeding in Patients Treated With Oral Anticoagulants: Proceedings Monograph From the Emergency Medicine Cardiac Research and Education Group-International Multidisciplinary Severe Bleeding Consensus Panel October 20, 2018

In this Emergency Medicine Cardiac Research and Education Group (EMCREG)-International Proceedings Monograph from the October 20, 2018, EMCREG-International Multidisciplinary Consensus Panel on Management of Severe Bleeding in Patients Treated With Oral Anticoagulants held in Orlando, FL, you will find a detailed discussion regarding the treatment of patients requiring anticoagulation and the reversal of anticoagulation for patients with severe bleeding. For emergency physicians, critical care physicians, hospitalists, cardiologists, internists, surgeons, and family physicians, the current approach and disease indications for treatment with anticoagulants such as coumadin, factor IIa, and factor Xa inhibitors are particularly relevant. When a patient treated with anticoagulants presents to the emergency department, intensive care unit, or operating room with severe, uncontrollable bleeding, achieving rapid, controlled hemostasis is critically important to save the patient's life. This EMCREG-International Proceedings Monograph contains multiple sections reflecting critical input from experts in Emergency Cardiovascular Care, Prehospital Emergency Medical Services, Emergency Medicine Operations, Hematology, Hospital Medicine, Neurocritical Care, Cardiovascular Critical Care, Cardiac Electrophysiology, Cardiology, Trauma and Acute Care Surgery, and Pharmacy. The first section provides a description of the current indications for the treatment of patients using oral anticoagulants including coumadin, the factor IIa (thrombin) inhibitor dabigatran, and factor Xa inhibitors such as apixaban and rivaroxaban. In the remaining sections, the treatment of patients presenting to the hospital with major bleeding becomes the focus. The replacement of blood components including red blood cells, platelets, and clotting factors is the critically important initial treatment for these individuals. Reversing the anticoagulated state is also necessary. For patients treated with coumadin, infusion of vitamin K helps to initiate the process of protein synthesis for the vitamin K-dependent coagulation proteins II, VII, IX, and X and the antithrombotic protein C and protein S. Repletion of clotting factors for the patient with 4-factor prothrombin complex concentrate, which includes factors II (prothrombin), VII, IX, and X and therapeutically effective concentrations of the regulatory proteins (protein C and S), provides real-time ability to slow bleeding. For patients treated with the thrombin inhibitor dabigatran, treatment using the highly specific, antibody-derived idarucizumab has been demonstrated to reverse the hypocoagulable state of the patient to allow blood clotting. In May 2018, andexanet alfa was approved by the US Food and Drug Administration to reverse the factor Xa anticoagulants apixaban and rivaroxaban in patients with major bleeding. Before the availability of this highly specific agent, therapy for patients treated with factor Xa inhibitors presenting with severe bleeding usually included replacement of lost blood components including red blood cells, platelets, and clotting factors and 4-factor prothrombin complex concentrate, or if not available, fresh frozen plasma. The evaluation and treatment of the patient with severe bleeding as a complication of oral anticoagulant therapy are discussed from the viewpoint of the emergency physician, neurocritical and cardiovascular critical care intensivist, hematologist, trauma and acute care surgeon, hospitalist, cardiologist, electrophysiologist, and pharmacist in an approach we hope that the reader will find extremely practical and clinically useful. The clinician learner will also find the discussion of the resumption of oral anticoagulation for the patient with severe bleeding after effective treatment important because returning the patient to an anticoagulated state as soon as feasible and safe prevents thrombotic complications. Finally, an EMCREG-International Severe Bleeding Consensus Panel algorithm for the approach to management of patients with life-threatening oral anticoagulant-associated bleeding is provided for the clinician and can be expanded in size for use in a treatment area such as the emergency department or critical care unit.

Spontaneous thoracic subdural hematoma associated with warfarin therapy: Case report with serial MRI

Background:

Spontaneous acute spinal subdural hematoma (SASSDH) is a rare but serious condition. We present diagnostic challenges and serial magnetic resonance imaging (MRI) findings of a patient who developed warfarin-associated thoracic SASSDH that was managed surgically.

Case Description:

A 68-year-old male presented with sudden onset left-sided chest and back pain, left leg weakness, and bilateral loss of sensations below T4 level. His symptoms developed after strenuous physical activity. He was taking warfarin for atrial fibrillation. His admission international normalized ratio was 4.25. Deterioration of neurological status 3 days after admission prompted spinal computed tomography (CT) scan that demonstrated nonhomogenous hyperdense intradural mass lesion in the thoracic spine. MRI demonstrated heterogeneous mass lesion on the left side of the spinal canal and thoracic myelopathy. The patient underwent urgent surgical evacuation of subacute subdural hematoma extending from T3 to T6 levels. MRI scan following the surgery showed no signs of the hematoma and thoracic myelopathy. MRI at 3 months follow-up demonstrated myelopathy extending from T3 to T6 levels with deviation of the spinal cord. The patient's motor strength and sensations improved but he retained left leg weakness with sensory deficit below T8 level.

Conclusions:

Spinal subdural hematoma should be suspected in patients presenting with acute onset back pain and myelopathy in the absence of trauma history. Coagulopathy should raise the suspicion for SASSDH. MRI is a valuable imaging modality for initial diagnosis to rule-out other lesions, and to assess postoperative re-bleeding and residual lesions.

Prothrombin Complex Concentrate for Warfarin-Associated Intracranial Bleeding in Neurosurgical Patients: A Single-Center Experience

Objective: The number of patients presenting with warfarin-associated intracranial bleeding and needing neurosurgical intervention is growing. Prothrombin complex concentrate (PCC) is commonly used for anti-coagulation reversal before emergent surgery. We present our experience with PCC use in patients presenting with coagulopathy and needing urgent craniotomy. Methods: We retrospectively identified all patients presenting with intracranial bleeding and coagulopathy due to warfarin use, requiring urgent neurosurgical procedures, from January, 2014 (implementation of 4-PCC therapy) until December, 2016. For coagulation reversal, all patients received 4-PCC (Octaplex) and vitamin K. Results: Thirty-five consecutive patients (17 men; median age 72 years) were administered 4-PCC before emergent neurosurgical procedures. The majority of patients presented with traumatic subdural hematoma (62%) and spontaneous intracerebral hemorrhage (32%). All patients were taking warfarin. Median international normalized ratio (INR) on admission was 2.94 (range: 1.20 to 8.60). Median 4-PCC dose was 2000 I.U. (range: 500 I.U. to 3000 I.U.). There was a statically significant decrease in INR (p < 0.01), PT (p < 0.01), and PTT (p = 0.02) after 4-PCC administration. Postoperative INR values were ≤3.00 in all patients, and seven (20%) patients had normal INR values. There were no 4-PCC related complications. Four (11%) patients developed subdural/epidural hematoma and 20 (57%) patients died. Mortality was associated with lower Glasgow coma scale (GCS) score. Conclusions: The 4-PCC facilitates INR reversal and surgery in patients presenting with warfarin-associated coagulopathy and intracranial bleeding requiring urgent neurosurgical intervention.

Managing Nonoperable Intracranial Bleeding Associated With Apixaban: A Series of 2 Cases

OBJECTIVE

To report 2 cases of nonoperable intracranial bleeding associated with apixaban managed by 3-factor prothrombin complex concentrate (PCC3).

CASE SUMMARIES

Case 1 presented with a 1.3-cm left parieto-occipital hemorrhage and a thin subdural hematoma (SDH) on the left tentorium of the brain about 6 hours after his last dose of apixaban. Case 2 presented with a 4-mm left parafalcine SDH with time of most recent apixaban dose unknown. The patients received 24.9 to 25.5 U/kg of PCC3 with none to 1 U fresh frozen plasma (FFP) and demonstrated minimal or no progression in lesions measured by repeat computed tomography (CT) after treatment. One patient was discharged to a skilled nursing facility after 8 days; the other patient was discharged to home after 18 days.

DISCUSSION

Apixaban has no specific antidote. Current bleeding management strategies are based on expert opinion. The risks and benefits for differing strategies are unclear, and little clinical experience for managing apixaban-associated intracranial bleeding has been reported to date. These cases describe the clinical use of PCC3 to manage parieto-occipital and subdural hemorrhage associated with apixaban in events not requiring surgical intervention.

CONCLUSION

In these 2 cases, 25 U/kg PCC3, with none to one unit FFP, ceased apixaban-associated intracranial bleeding without apparent thrombogenic complications.

Do Age and Anticoagulants Affect the Natural History of Acute Subdural Hematomas?

Acute subdural hematoma is a serious complication following traumatic brain injury. Large volume hematomas or those with underlying brain injury can cause mass effect, midline shift, and eventually herniation of the brain. Acute subdural hematomas in the young are associated with high-energy trauma and often have underlying contusions, while acute subdural hematomas in the elderly are associated with minor trauma and an absence of underlying contusions, even though the elderly are more likely to be on anticoagulants or anti-platelet therapy. In the young patients with high impact injuries the hematomas tend to be small and the underlying brain injury and swelling is responsible for the increased intracranial pressure and midline shift. In the elderly, the injuries are low impact (e.g fall from standing), the underlying brain is intact, and the volume of the hematoma itself produces symptoms. In addition the use of anticoagulants and antiplatelet agents in the elderly population has been thought to be a poor prognostic indicator and is considered to be responsible for larger hematomas and poor outcome. When managed conservatively, acute subdural hematomas can sometimes progress to chronic subdural hematoma formation, further enlargement, seizures, and progressive midline shift. Another potential difference in the young and the elderly is brain atrophy, which increases the potential space to accommodate a larger hematoma. It is not known if these two groups differ in other ways that might have implications for treatment or prognosis. In this paper, we investigate the clinical course of 80 patients admitted to our institution with acute subdural hematomas, to identify differences in patients above or below the age of 65 years. The natural progression/resolution of acute subdural hematomas was mapped by measuring volume expansion/regression over time. In this retrospective chart review, we investigated clinical baseline metrics and subsequent volumetric expansion outcomes between patients < 65 years old (N=44) and those > 65 years old (N=36). Volume was estimated by the ABC/2 method. We observed a statistically significant difference between groups in use of anticoagulants χ² =40.305 with p < 0.001, corrective platelet administration χ² =19.380 with p < 0.001, gender χ² =14.573 with p < 0.001, and Glasgow Coma Scale with χ² =23.125 (p=0.026). Overall outcomes were similar in the two groups. Younger patients on average had worse presenting GCS scores, but recovered comparable to older patients. No significant difference in rate of volume expansion, resolution time, or need for surgical treatment was seen between these two groups. We conclude that the initial volume, size, and severity of subdural hematoma determined by the Glasgow Coma Scale score is more likely to predict surgery or future expansion than age of the patient. Patients on oral anti-coagulants that are given appropriate medical reversal agents early do quite well and no impact on the eventual outcome could be demonstrated. Further work is needed to establish better predictors of future volume expansion, and progression to chronic subdural hematoma based on improved severity scales.

Effects of VKORC1 Genetic Polymorphisms on Warfarin Maintenance Dose Requirement in a Chinese Han Population

Background

VKORC1 is reported to be capable of treating several diseases with thrombotic risk, such as cardiac valve replacement. Some single-nucleotide polymorphisms (SNPs) in VKORC1 are documented to be associated with clinical differences in warfarin maintenance dose. This study explored the correlations of VKORC1–1639 G/A, 1173 C/T and 497 T/G genetic polymorphisms with warfarin maintenance dose requirement in patients undergoing cardiac valve replacement.

Material/Methods

A total of 298 patients undergoing cardiac valve replacement were recruited. During follow-up, clinical data were recorded. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was applied to detect VKORC1–1639 G/A, 1173 C/T and 497 T/G polymorphisms, and genotypes were analyzed.

Results

Correlations between warfarin maintenance dose and baseline characteristics revealed statistical significances of age, gender and operation methods with warfarin maintenance dose (all P<0.05). Warfarin maintenance dose in VKORC1–1639 G/A AG + GG carriers was obviously higher than in AA carriers (P<0.001). As compared with patients with TT genotype in VKORC1 1173 C/T, warfarin maintenance dose was apparently higher in patients with CT genotype (P<0.001). Linear regression analysis revealed that gender, operation method, method for heart valve replacement, as well as VKORC1–1639 G/A and 1173 C/T gene polymorphisms were significantly related to warfarin maintenance dose (all P<0.05).

Conclusions

VKORC1 gene polymorphisms are key genetic factors to affect individual differences in warfarin maintenance dose in patients undergoing cardiac valve replacement; meanwhile, gender, operation method and method for heart valve replacement might also be correlate with warfarin maintenance dose.

Periprocedural warfarin reversal with prothrombin complex concentrate

INTRODUCTION

Approximately 10% of chronically anticoagulated patients require an invasive procedure annually. One in 10 procedures is emergent and requires prompt anticoagulation reversal. The study objective is to determine the safety and efficacy of a 3 factor prothrombin complex concentrate (PCC) for periprocedural anticoagulation reversal.

MATERIALS AND METHODS

Consecutive patients receiving 3 factor PCC for warfarin reversal for either urgent/emergent invasive procedures or major bleeding were analyzed. Primary endpoints included percent achieving INR <1.5, peri-operative major hemorrhage, thromboembolism and death during the 40day post-infusion period.

RESULTS

Between January 1, 2010-December 31, 2012, 52 patients were treated with PCC for pre-procedural warfarin reversal and 113 patients for major bleeding. Within the peri-procedure group, there were 24 intra-abdominal surgeries, 12 percutaneous interventions, 6 cardiothoracic surgeries, 5 orthopedic and 3 endoscopic procedures. INR values <1.5 were achieved in 51% at 2.5h post-infusion. Major bleeding (13%), thromboembolism (13%) and mortality rates (15%) were high. Within the major bleeding group, PCC therapy reversed INR values (<1.5) in 75% of patients within 4h. For this group, thromboembolism (21%) and mortality rates (16%) were likewise high. Post-PCC anticoagulation, reinitiated in 37%, had no impact on bleeding or thrombotic complications. Mortality rates were threefold higher for those patients not restarting warfarin therapy.

CONCLUSIONS

Although PCC therapy promptly and effectively reverses INR values for patients requiring urgent/emergent invasive procedure both thromboembolic and fatal complications are soberingly high and call for judicious use of these agents in these high risk populations.

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.

VKORC1 -1639G/A and 1173 C/T Genetic Polymorphisms Influence Individual Differences in Warfarin Maintenance Dose

OBJECTIVE

In this study, we investigated two VKORC1 gene polymorphisms, -1639G/A and 1173C/T, for effects on warfarin maintenance dosage in valvular heart disease (VHD) patients after cardiac valve replacement (CVR).

METHODS

A total of 219 VHD patients receiving warfarin therapy after CVR surgery were recruited to this study between June 2010 and December 2013. Basic clinical data, prothrombin time, warfarin maintenance dose, and blood samples were collected from all patients. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses were used to analyze the VKORC1 -1639G/A and 1173C/T polymorphisms. SPSS version 19.0 software was used for statistical analysis of the data.

RESULTS

Patients with either the AG+or GG genotype (n=32) of the VKORC1 -1639G/A polymorphism required a significantly higher warfarin dose compared to patients with the AA genotype (n=187) (4.36±1.03 mg/day vs. 2.95±0.94 mg/day; p<0.001). Similarly, patients carrying the CT genotype (n=28) of the VKORC1 1173C/T polymorphism also required a significantly higher warfarin dose compared to those with the TT genotype (n=191) (4.19±0.99 mg/day vs. 3.00±0.94 mg/day; p<0.001). Linear regression analysis showed that gender, age, weight, and VKORC1 -1639G/A and 1173C/T polymorphisms were correlated with individual differences in warfarin maintenance dose (all p<0.05).

CONCLUSION

We present evidence that the two VKORC1 polymorphisms, -1639G/A and 1173C/T, are key genetic factors influencing individual differences in warfarin maintenance dose in VHD patients who underwent CVR. Gender, age, and weight also independently correlated with warfarin maintenance dose.

Risk of thromboembolic events after protocolized warfarin reversal with 3-factor PCC and factor VIIa

Bleeding events and life-threatening hemorrhage are the most feared complications of warfarin therapy. Prompt anticoagulant reversal aimed at replacement of vitamin K-dependent clotting factors is essential to promote hemostasis. A retrospective cohort study of warfarin-treated patients experiencing a life-threatening hemorrhage treated with an institution-specific warfarin reversal protocol (postimplementation group) and those who received the prior standard of care (preimplementation group) was performed. The reversal protocol included vitamin K, 3-factor prothrombin complex concentrate, and recombinant factor VIIa. Demographic and clinical information, anticoagulant reversal information, and all adverse events attributed to warfarin reversal were recorded. A total of 227 patients were included in final analysis, 109 in the preimplementation group and 118 in the postimplementation group. Baseline patient characteristics were similar in both groups, with the exception of higher average Sequential Organ Failure Assessment scores in the postimplementation group (P = .0005). The most common indication for anticoagulation reversal was intraparenchymal hemorrhage. Prereversal international normalized ratios (INRs) were similar in both groups. Attainment of INR normalization to less than 1.4 was higher, and rebound INR was lower in the postimplementation group (P < .0001; P = .0013). Thromboembolic complications were significantly higher in the postimplementation group (P = .003). Elevated baseline Sequential Organ Failure Assessment score and mechanical valve as an indication for anticoagulation were independently associated with thrombotic complications (P = .005). A warfarin reversal protocol consisting of 3-factor prothrombin complex concentrate, recombinant factor VIIa, and vitamin K more consistently normalized INR values to less than 1.4 as compared to the prior standard of care in a diverse patient population. This success came at the cost of a 2-fold increase in risk of thromboembolic complications.

Design and rationale for RE-VERSE AD: A phase 3 study of idarucizumab, a specific reversal agent for dabigatran

Idarucizumab, a Fab fragment directed against dabigatran, produced rapid and complete reversal of the anticoagulation effect of dabigatran in animals and in healthy volunteers. The Study of the REVERSal Effects of Idarucizumab in Patients on Active Dabigatran (RE-VERSE AD™) is a global phase 3 prospective cohort study aimed at investigating idarucizumab in dabigatran-treated patients who present with uncontrollable or life-threatening bleeding, and in those requiring urgent surgery or intervention. We describe the rationale for, and design of the trial (clinicaltrials.gov NCT02104947).

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.

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.

Outcomes Associated With Prothrombin Complex Concentrate for International Normalized Ratio Reversal in Patients on Oral Anticoagulants With Acute Bleeding

BACKGROUND

Management of bleeding in patients on oral anticoagulants (OACs) is crucial in optimizing outcomes. No large studies examine 3-factor prothrombin complex concentrate (PCC) for OAC reversal.

OBJECTIVE

To assess outcomes after administration of 3-factor PCC for reversal of international normalized ratio (INR).

METHOD

We conducted an institutional review board-approved retrospective cohort study in all patients admitted to our level II trauma center over a 5-year period from 2007 to 2012 who received PCC for INR reversal and bleeding management. The primary outcome was assessment of efficacy as measured by achievement of INR < 1.5. Secondary objectives were to evaluate: factors associated with achievement of target INR, cessation of bleeding, mortality, outcome differences with or without fresh frozen plasma (FFP) or protocol utilization, safety, and cost.

RESULT

A total of 403 patients were evaluated. Target INR was achieved in 88.8% of patients and was influenced by baseline INR. Associated factors were younger age (P = 0.02), utilization of the institution's protocol (P < 0.01), and concomitant administration of vitamin K (P < 0.01). Concomitant FFP did not affect achievement. Bleeding cessation occurred in 333 (82.6%) patients, and 68 (16.9%) patients died. Patients who achieved target INR were more likely to have bleeding cessation (P < 0.01). The odds of survival for those who reached target INR was 3.8 times greater (P < 0.01). The incidence of thromboembolism was 3.7%.

CONCLUSION

Three-factor PCC administration with IV vitamin K was effective for INR reversal and bleeding cessation and should continue to be a mainstay of therapy pending head-to-head outcome and cost comparisons with 4-factor products.

The epidemic of pre-injury oral antiplatelet and anticoagulant use

BACKGROUND

As the population ages, an increasing number of trauma patients are taking antiplatelet and anticoagulant medications (ACAP) prior to their injuries. These medications increase their risk of hemorrhagic complications, particularly intracerebral hemorrhage. Clopidogrel and warfarin are common and their mechanisms well understood, but optimal reversal methods continue to evolve. The novel direct thrombin and factor Xa inhibitors are less well described and do not have existing antidotes.

METHODS

This article reviews the relevant literature on traumatic outcomes with use of ACAP medications, as well as data on ideal reversal strategies. Suggested algorithms are introduced, and future research directions discussed.

RESULTS

Although they are beneficial in preventing clot formation, once bleeding occurs ACAP medications contribute to increased morbidity and mortality, particularly in geriatric patient populations. The efficacy of clopidogrel reversal with platelet transfusions and DDAVP remains unclear. Warfarin use is best treated with the algorithm-driven use of plasma, vitamin K, prothrombin complex concentrates (PCCs) and possibly recombinant factor VIIa depending upon specific patient and injury factors. Optimal treatment for direct thrombin and factor Xa inhibitors has yet to be developed, but PCCs are promising for rivaroxaban and apixaban while dabigatran is best treated with medication cessation and the possible addition of activated PCCs or hemodialysis.

CONCLUSION

New developments in reversal of the ACAP medications are promising, particularly PCCs for warfarin and the factor Xa inhibitors. Function assays and clear antidotes are needed for the thrombin and Xa inhibitors. Research on outcomes and appropriate treatments is actively ongoing.

Controversies and evolving new mechanisms in subarachnoid hemorrhage

Despite decades of study, subarachnoid hemorrhage (SAH) continues to be a serious and significant health problem in the United States and worldwide. The mechanisms contributing to brain injury after SAH remain unclear. Traditionally, most in vivo research has heavily emphasized the basic mechanisms of SAH over the pathophysiological or morphological changes of delayed cerebral vasospasm after SAH. Unfortunately, the results of clinical trials based on this premise have mostly been disappointing, implicating some other pathophysiological factors, independent of vasospasm, as contributors to poor clinical outcomes. Delayed cerebral vasospasm is no longer the only culprit. In this review, we summarize recent data from both experimental and clinical studies of SAH and discuss the vast array of physiological dysfunctions following SAH that ultimately lead to cell death. Based on the progress in neurobiological understanding of SAH, the terms "early brain injury" and "delayed brain injury" are used according to the temporal progression of SAH-induced brain injury. Additionally, a new concept of the vasculo-neuronal-glia triad model for SAH study is highlighted and presents the challenges and opportunities of this model for future SAH applications.

Prothrombin complex concentrate facilitates emergency spinal surgery in anticoagulated patients

BACKGROUND

Oral anticoagulants are commonly used in the ageing population and therefore, spine surgeons are increasingly confronted with anticoagulated patients requiring surgical therapy. 'Bridging therapies' with heparins are established in elective settings, but the time frame for haemostasis restoration may be too long for patients presenting with acute spinal pathology and impending disability. The goal of this study was to analyse the feasibility of prothrombin complex concentrate (PCC) administration to facilitate emergency spinal surgery in anticoagulated patients.

METHOD

A retrospective analysis of the institutional database of neurosurgical patients receiving PCC from February 2007 to December 2013 (n = 485) identified 18 patients who received PCC prior to emergency spinal surgery. Clinical characteristics, as well as modalities of PCC administration and parameters of haemostasis were analysed. Furthermore, haemorrhagic complications and thromboembolic events in the further course were evaluated.

RESULTS

Spinal pathologies requiring urgent neurosurgical decompression were spinal haematoma (n = 9), spinal metastasis (n = 5), vertebral body fracture (n = 2), and disc herniation (n = 2). The mean international normalized ratio (INR) on admission was 2.27 ± 1.20 and after administration of PCC (mean: 1,944 ± 953 I.U.), INR significantly decreased to 1.12 ± 0.10 (p < 0.001). Emergency surgery was initiated within 4.4 h after PCC administration (range: 0-16.6 h). Postoperatively, symptoms improved in 12 patients (66.7 %). There were two deaths (11 %), one caused by acute myocardial infarction on the fourth postoperative day. Bleeding complications occurred in two patients (epidural haemorrhage n = 1, rectal tumour haemorrhage n = 1).

CONCLUSIONS

The administration of PCC facilitates emergency spinal surgery in anticoagulated patients who present with acute spinal pathology requiring urgent neurosurgical decompression. The risk of PCC-associated thromboembolic events seems to be low and justifies the use of PCC in order to avoid permanent disablement resulting from delayed surgery or non-operation.

Prothrombin Complex Concentrate Accelerates International Normalized Ratio Reversal and Diminishes the Extension of Intracranial Hemorrhage in Geriatric Trauma Patients

Warfarin therapy increases the incidence intracranial hemorrhage (ICH), especially in the geriatric population. Timely reversal of international normalized ratio (INR) is integral in the management of these patients for whom fresh frozen plasma (FFP) with vitamin K is the standard of treatment. We hypothesized that implementing a protocol that used prothrombin complex concentrate (PCC) would reverse INR values more swiftly and decrease the amount of FFP administered. In November 2011, a protocol was implemented for administering PCC to the geriatric population on warfarin admitted for life-threatening bleeds. These patients received 25 IU/kg ideal body weight of a three-factor PCC (Profilnine SD) if their INR was over 1.5 or greater. FFP was given if follow-up INR revealed an INR of 1.5 or greater. Retrospectively the data from 29 patients who received PCC were compared with a historical control group of 34 patients. Protocol use resulted in a significantly faster INR reversal (PCC: 151.6 ± 84.3 minutes vs control: 485.0 ± 321 minutes; P < 0.001), time to achieve an INR less than 1.5 (PCC: 484 ± 242 minutes vs control: 971 ± 1208 minutes; P = 0.036), and less FFP administered (PCC: 1.3 ± 1.0 vs control:3.3 ± 1.5; P < 0.001). PCC patients had a decreased incidence of progression of their ICH (PCC: 17.2% vs control: 44.2%; P = 0.031). Rapid reversal of coagulopathy in geriatric patients on warfarin is vital to limit the extent of ICH. PCC allows a much more rapid reversal than standard treatment with only FFP and vitamin K. Adopting such a protocol is associated not only with a more rapid reversal and less FFP use, but also less patients went on to extend their head bleeds.

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.

Rapid reversal of warfarin-associated hemorrhage in the emergency department by prothrombin complex concentrates

Life-threatening warfarin-associated hemorrhage is common, with a high mortality. In the United States, the most commonly used therapies--fresh frozen plasma and vitamin K--are slow and unpredictable and can result in volume overload. Outside of the United States, prothrombin complex concentrates are often used instead; these pooled plasma products reverse warfarin anticoagulation in minutes rather than hours. This article reviews the literature relating to warfarin reversal with fresh frozen plasma, prothrombin complex concentrates, and recombinant factor VIIa and provides elements for a management protocol based on this literature.