Warfarin-reversal: results of a phase III study with pasteurised, nanofiltrated prothrombin complex concentrate

Use of four-factor prothrombin complex concentrate in the reversal of warfarin-induced and nonvitamin K antagonist-related coagulopathy

: To evaluate the efficacy of international normalized ratio (INR) reversal using four-factor prothrombin complex concentrate (4F-PCC) in nonmedication-induced coagulopathy. We performed a single-site, retrospective cohort study of patients receiving off-label use of 4F-PCC. Cohorts included liver dysfunction if they had acute liver decompensation or cirrhosis without other causative factors of liver failure such as sepsis, coagulopathy of acute sepsis (CAS) if they had documentation of sepsis and no underlying liver disorder, known factor deficiencies, or medication-induced coagulopathy, or warfarin if they were taking warfarin. Patients with unknown medication or direct oral anticoagulant usage were excluded. 4F-PCC was administered 32 times in 26 patients for nonvitamin-K antagonist related coagulopathy (11 CAS and 21 liver dysfunction) and 47 administrations were in warfarin patients. Liver dysfunction patients had a mean model for end-stage liver disease score of 28 ± 10. CAS and warfarin patients had significant INR reductions (ΔINR 1.9, P < 0.01; ΔINR 3.9, P < 0.01, respectively). Liver dysfunction patients mean change in INR trended toward significance (ΔINR 0.7, P = 0.09). Patients who received 4F-PCC based upon previously established dosing guidelines for moderate elevations in INR (20-30 IU/kg) doing demonstrated similar reductions in INR between CAS and warfarin patients (ΔINR 1.3, P = 0.03, ΔINR 1.0 P < 0.01, respectively). 4F-PCC significantly reduces the INR in CAS patients and trended toward significant reductions in liver dysfunction patients. Adequately powered, prospective trials are needed to demonstrate 4F-PCC efficacy in reversal of these coagulopathies.

Reversal of rivaroxaban anticoagulation by haemostatic agents in rats and primates

Rivaroxaban is an oral, direct factor Xa inhibitor for the management of thromboembolic disorders. Despite its short half-life, the ability to reverse rivaroxaban anticoagulation could be beneficial in life-threatening emergencies. The potential of prothrombin complex concentrate (PCC; Beriplex®), activated PCC (aPCC; FEIBA®) or recombinant activated factor VII (rFVIIa; NovoSeven®) to reverse rivaroxaban in rats and baboons was investigated. Anaesthetised rats pre-treated with intravenous rivaroxaban (2 mg/kg) received intravenous rFVIIa (100/400 μg/kg), PCC (25/50 U/kg) or aPCC (50/100 U/kg) after initiation of bleeding. Clotting times and bleeding times (BTs) were recorded. Rivaroxaban was administered as an intravenous 0.6 mg/kg bolus followed by continuous 0.6 mg/kg/hour infusion in baboons. Animals received intravenous aPCC 50 U/kg (2 U/kg/minute) or rFVIIa 210 μg/kg. BT and clotting parameters were measured. In rats pre-treated with high-dose rivaroxaban, PCC 50 U/kg, aPCC 100 U/kg and rFVIIa 400 μg/kg significantly reduced BT vs rivaroxaban alone (5.4 ± 1.4-fold to 1.5 ± 0.4-fold [p<0.05]; 3.0 ± 0.4-fold to 1.4 ± 0.1-fold [p<0.001]; and 3.5 ± 0.7-fold to 1.7 ± 0.2-fold [p<0.01] vs baseline, respectively). In baboons pre-infused with rivaroxaban and then given aPCC, BT increased by 2.0 ± 0.2-fold and aPCC returned BT to baseline for the duration of its infusion. rFVIIa reduced BT from 2.5 ± 0.3-fold over baseline to 1.7 ± 0.3-fold over baseline. Prolongation of prothrombin time was reduced by PCC, aPCC and rFVIIa in both species. Rivaroxaban reduced thrombin-antithrombin levels; application of PCC and aPCC, but not rFVIIa, increased these levels. In conclusion, PCC, aPCC or rFVIIa have the potential to reverse the anticoagulant and anti-haemostatic effects of rivaroxaban.

Treatment of brodifacoum overdose with prothrombin complex concentrate

PURPOSE

A case of brodifacoum overdose and its treatment with prothrombin complex concentrate (PCC) are reported.

SUMMARY

A 44-year-old Caucasian woman weighing 62 kg arrived at the emergency department with a chief complaint of lower left leg pain for two days. A computed tomography (CT) scan of the abdomen revealed perihepatic fluid collection (likely a hematoma), a small-bowel intramural hematoma, and blood in the paracolic gutter. A CT scan of the patient's left foot showed soft tissue swelling without evidence of fracture or dislocation. The patient was diagnosed with left extremity compartment syndrome secondary to hematoma and trauma. The patient had a history of depression and anxiety and eventually admitted to ingesting large doses of brodifacoum the week prior with suicidal intentions. The patient was treated with phytonadione 20 mg i.v., 1 unit of fresh frozen plasma (FFP), and 1 unit of packed red blood cells. Laboratory test values measured in the intensive care unit revealed an International Normalized Ratio (INR) of 15, a prothrombin time of >120 seconds, and a partial prothromboplastin time of >180 seconds. After consulting with a local poison center, phytonadione 50 mg i.v., PCC 3100 units, and 4 units of FFP were immediately administered to reverse the patient's coagulopathy. The dose of oral phytonadione was lowered based on INR stability. Once the coagulopathy was stabilized, the patient was transferred to an inpatient psychiatric facility on phytonadione 10 mg daily orally to maintain a stable INR.

CONCLUSION

A 44-year-old woman who intentionally ingested brodifacoum was successfully treated with phytonadione, PCC, and FFP.

A new kid on the block: Outcomes with Kcentra 1 year after approval

BACKGROUND

As the population ages, more trauma patients are admitted with coagulopathy. Fresh frozen plasma is effective in reversing coagulopathy caused by warfarin; however, it is not appropriate for all patients. Prothrombin complex concentrates (PCCs) are an alternative for patients who require emergent reversal, minimal-volume administration and who have a supratherapeutic international normalized ratio (INR). A four-factor PCC initially approved in Europe is now available in the United States. We sought to review our experience with Kcentra (4F-PCC) in the first year following Food and Drug Administration approval.

METHODS

All trauma patients admitted to an academic Level 1 trauma center between July 15, 2013, and July 15, 2014, who received 4F-PCC for reversal of warfarin-induced coagulopathy were reviewed. 4F-PCC was given as per protocol. Univariate analysis was performed to examine patient demographics, injury characteristics, coagulation studies, 4F-PCC dose, vitamin K use, transfusions, response to reversal, duration of reversal, complications, and mortality.

RESULTS

Twenty-six patients met study criteria. Of these patients, 34.6% were reversed because of intracranial hemorrhage. The mean INR decreased from 5.7 ± 6.1 (range, 1.6-30) to 1.5 ± 0.4 (range, 1.2-2.6) after 4F-PCC administration. One patient (3.8%) received concurrent fresh frozen plasma. For patients with an initial INR greater than 5.0, the mean INR decreased from 12.0 ± 8.2 to 1.6 ± 0.5. Forty-eight hours following 4F-PCC administration, mean INR for all patients remained 1.4 ± 0.4 (range, 1.0-2.6). Of the patients, 80.8% received vitamin K over this period. Fourteen patients had a pre-4F-PCC thromboelastogram; four were hypocoagulable. Two patients had repeat thromboelastograms after 4F-PCC was given, which demonstrated normal coagulation. Of the patients with intracranial hemorrhage, 66.7% showed radiographic progression of the initial insult on post-4F-PCC head computed tomography, while only 11.1% progressed clinically. In-hospital mortality was 0%. There were no thromboembolic complications.

CONCLUSION

4F-PCC effectively reverses elevated INRs in trauma patients with warfarin-induced coagulopathy, with results lasting more than 48 hours after administration.

LEVEL OF EVIDENCE

Therapeutic study, level V.

Use of Prothrombin Complex Concentrate as an Adjunct to Fresh Frozen Plasma Shortens Time to Craniotomy in Traumatic Brain Injury Patients

BACKGROUND:

The use of prothrombin complex concentrate (PCC) to reverse acquired (coagulopathy of trauma) and induced coagulopathy (preinjury warfarin use) is well defined.

OBJECTIVE:

To compare outcomes in patients with traumatic brain injury without warfarin therapy receiving PCC as an adjunct to fresh frozen plasma (FFP) therapy compared with patients receiving FFP therapy alone.

METHODS:

All patients with traumatic brain injury coagulopathy without warfarin therapy who received PCC (25 IU/kg) in conjunction with FFP or FFP alone at our Level I trauma center were reviewed. Coagulopathy was defined as an international normalized ratio &gt;1.5. The groups (PCC + FFP vs FFP alone) were matched using propensity score matching on a 1:2 ratio for age, sex, Glasgow Coma Scale score, Injury Severity Score, head Abbreviated Injury Scale score, and international normalized ratio (INR) on presentation. The primary outcome measure was time to craniotomy. Secondary outcome measures were blood product requirements, cost of therapy, and mortality.

RESULTS:

A total of 1641 patients were reviewed, 222 of whom were included (PCC + FFP, 74; FFP, 148). The mean ± standard deviation age was 46.4 ± 21.7 years, the median (range) Glasgow Coma Scale score was 8 (3-12), and the mean ± standard deviation INR on presentation was 1.92 ± 0.6. PCC + FFP therapy was associated with an accelerated correction of INR (P = .001) and decrease in overall pack red blood cell (P = .035) and FFP (P = .041) administration requirement. Craniotomy was performed in 26.1% of patients (n = 58). Patients who received PCC + FFP therapy had faster time to craniotomy (P = .028) compared with patients who received FFP therapy alone.

CONCLUSION:

PCC as an adjunct to FFP decreases the time to craniotomy with faster correction of INR and concomitant decrease in the need for blood product requirement in patients with traumatic brain injury exclusive of prehospital warfarin therapy.

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.

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.

A review of current agents for anticoagulation for the critical care practitioner

There has been a tremendous boom in the arena of anticoagulant therapy recently. Although the indications for these agents reside in the noncritical care environment, over time, the impact of these agents have infiltrated the critical care environment particularly due to devastating complications with associated use. With so many newer agents on the market or coming down the pipeline, it is easy to become overwhelmed. It is important that the critical care practitioner does not ignore these agents but becomes familiar with them to better prepare for the management of patients on one or more anticoagulant agents in the intensive care unit. To equip the critical care practitioners with the knowledge about commonly used anticoagulants, we provide an extensive review of the pharmacology, indications, and adverse effects related to these agents as well as suggestions on preventing or managing complications.

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.

Long-term safety and efficacy of a pasteurized nanofiltrated prothrombin complex concentrate (Beriplex P/N): a pharmacovigilance study

Background

The rapid reversal of the effects of vitamin K antagonists is often required in cases of emergency surgery and life-threatening bleeding, or during bleeding associated with high morbidity and mortality such as intracranial haemorrhage. Increasingly, four-factor prothrombin complex concentrates (PCCs) containing high and well-balanced concentrations of vitamin K-dependent coagulation factors are recommended for emergency oral anticoagulation reversal. Both the safety and efficacy of such products are currently in focus, and their administration is now expanding into the critical care setting for the treatment of life-threatening bleeding and coagulopathy resulting either perioperatively or in cases of acute trauma.

Methods

After 15 yr of clinical use, findings of a pharmacovigilance report (February 1996–March 2012) relating to the four-factor PCC Beriplex P/N (CSL Behring, Marburg, Germany) were analysed and are presented here. Furthermore, a review of the literature with regard to the efficacy and safety of four-factor PCCs was performed.

Results

Since receiving marketing authorization (February 21, 1996), ∼647 250 standard applications of Beriplex P/N have taken place. During this time, 21 thromboembolic events judged to be possibly related to Beriplex P/N administration have been reported, while no incidences of viral transmission or heparin-induced thrombocytopenia were documented. The low risk of thromboembolic events reported during the observation period (one in ∼31 000) is in line with the incidence observed with other four-factor PCCs.

Conclusions

In general, four-factor PCCs have proven to be well tolerated and highly effective in the rapid reversal of vitamin K antagonists.

Coagulation management in patients undergoing mechanical circulatory support

The incidence of bleeding and thrombo-embolic complications in patients undergoing mechanical circulatory support therapy remains high and is associated with bad outcomes and increased costs. The need for anticoagulation and anti-platelet therapy varies widely between different pulsatile and non-pulsatile ventricular-assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) systems. Therefore, a unique anticoagulation protocol cannot be recommended. Notably, most thrombo-embolic complications occur despite values of conventional coagulation tests being within the targeted range. This is due to the fact that conventional coagulation tests such as international normalised ratio (INR), activated partial thromboplastin time (aPTT) and platelet count cannot detect hyper- or hypofibrinolysis, hypercoagulability due to tissue factor expression on circulating cells or increased clot firmness, and platelet aggregation as well as response to anti-platelet drugs. By contrast, point-of-care (POC) whole blood viscoelastic tests (thromboelastometry/-graphy) and platelet function tests (impedance or turbidimetric aggregometry) reflect in detail the haemostatic status of patients undergoing mechanical circulatory support therapy and the efficacy of their anticoagulation and antiaggregation therapy. Therefore, monitoring of haemostasis using POC thromboelastometry/-graphy and platelet function analysis is recommended during mechanical circulatory support therapy to reduce the risk of bleeding and thrombo-embolic complications. Notably, these haemostatic tests should be performed repeatedly during mechanical circulatory support therapy since thrombin generation, clot firmness and platelet response may change significantly over time with a high inter- and intra-individual variability. Furthermore, coagulation management can be hampered in non-pulsatile VADs by acquired von Willebrand syndrome, and in general by acquired factor XIII deficiency as well as by heparin-induced thrombocytopenia. In addition, POC testing can be used in bleeding patients to guide calculated goal-directed therapy with allogeneic blood products, haemostatic drugs and coagulation factor concentrates to optimise the haemostasis and to minimise transfusion requirements, transfusion-associated adverse events and to avoid thrombo-embolic complications, as well. However, coagulation management in patients undergoing mechanical circulatory support therapy is somehow like navigating between Scylla and Charybdis, and development of protocols based on POC testing seems to be beneficial.

Tissue factor structure and function

Tissue factor (TF) is an integral membrane protein that is essential to life. It is a component of the factor VIIa-TF complex enzyme and plays a primary role in both normal hemostasis and thrombosis. With a vascular injury, TF becomes exposed to blood and binds plasma factor VIIa, and the resulting complex initiates a series of enzymatic reactions leading to clot formation and vascular sealing. Many cells, both healthy, and tumor cells, produce detectable amounts of TF, especially when they are stimulated by various agents. Despite the relative simplicity and small size of TF, there are numerous contradictory reports about the synthesis and presentation of TF on blood cells and circulation in normal blood either on microparticles or as a soluble protein. Another subject of controversy is related to the structure/function of TF. It has been almost commonly accepted that cell-surface-associated TF has low (if any) activity, that is, is "encrypted" and requires specific conditions/reagents to become active, that is, "decrypted." However there is a lack of agreement related to the mechanism and processes leading to alterations in TF function. In this paper TF structure, presentation, and function, and controversies concerning these features are discussed.

Current management of massive hemorrhage in trauma

Hemorrhage remains a major cause of potentially preventable deaths. Trauma and massive transfusion are associated with coagulopathy secondary to tissue injury, hypoperfusion, dilution, and consumption of clotting factors and platelets. Concepts of damage control surgery have evolved prioritizing early control of the cause of bleeding by non-definitive means, while hemostatic control resuscitation seeks early control of coagulopathy.Hemostatic resuscitation provides transfusions with plasma and platelets in addition to red blood cells in an immediate and sustained manner as part of the transfusion protocol for massively bleeding patients. Although early and effective reversal of coagulopathy is documented, the most effective means of preventing coagulopathy of massive transfusion remains debated and randomized controlled studies are lacking. Viscoelastical whole blood assays, like TEG and ROTEM however appear advantageous for identifying coagulopathy in patients with severe hemorrhage as opposed the conventional coagulation assays.In our view, patients with uncontrolled bleeding, regardless of it's cause, should be treated with hemostatic control resuscitation involving early administration of plasma and platelets and earliest possible goal-directed, based on the results of TEG/ROTEM analysis. The aim of the goal-directed therapy should be to maintain a normal hemostatic competence until surgical hemostasis is achieved, as this appears to be associated with reduced mortality.

Reversal of antithrombotic agents

Anticoagulants are the mainstay of therapy for thromboembolic diseases. In addition to the more traditional agents, new oral anticoagulants, including dabigatran etexilate, rivaroxaban, and apixaban, have been shown to be effective across several indications. Bleeding is a serious complication associated with any anticoagulant, but many of the traditional parenteral and new oral agents do not currently have specific antidotes. This review describes available and future options for the reversal of the effects of anticoagulants, in particular the new oral agents and discusses current management strategies for bleeding events in clinical practice.

Prothrombin complex concentrate versus standard therapies for INR reversal in trauma patients receiving warfarin

BACKGROUND

Prothrombin complex concentrate (PCC) is recommended as a therapy to be considered for the reversal of warfarin's effects. Few published data are available on the use of PCC for this indication in traumatically injured patients.

OBJECTIVE

To determine whether the addition of PCC to standard approaches to warfarin reversal more rapidly corrects the international normalized ratio (INR) in injured patients.

METHODS

A retrospective analysis was performed in trauma patients who were on warfarin preinjury from January 2007 to September 2009 at North Memorial Medical Center. Data were collected from medical records and the trauma registry. Patients were separated based on whether or not they received PCC. The groups were compared on the basis of demographics, units of fresh frozen plasma (FFP), vitamin K use, units of PCC, number of patients achieving an INR of 1.5 or less, time to an INR of 1.5 or less, mortality, intensive care unit (ICU) and hospital length of stay, and the incidence of thromboembolic events during hospitalization.

RESULTS

Thirty-one patients were included in the analysis; 13 patients who received a total mean (SD) dose of 2281 (1053) units (25.6 [12.2] units/kg) of PCC (Profilnine SD) were compared to 18 patients who did not receive PCC. There was no significant difference between groups in FFP units received or the number of patients who received vitamin K. Most patients in both groups achieved an INR of 1.5 or less (92% PCC vs 89% no PCC). However, the mean time to achieve an INR of 1.5 or less was 16:59 (20:53) hours in the PCC group versus 30:03 (23:10) hours in the no PCC group (p = 0.048). There were 3 deaths in the PCC group and no deaths in the no PCC group (p = 0.06). ICU and hospital length of stay and number of thromboembolic events did not differ significantly between the 2 groups.

CONCLUSIONS

PCC, when added to FFP and vitamin K, resulted in a more rapid time to reversal of the INR.

2011 update to the Society of Thoracic Surgeons and the Society of Cardiovascular Anesthesiologists blood conservation clinical practice guidelines

BACKGROUND

Practice guidelines reflect published literature. Because of the ever changing literature base, it is necessary to update and revise guideline recommendations from time to time. The Society of Thoracic Surgeons recommends review and possible update of previously published guidelines at least every three years. This summary is an update of the blood conservation guideline published in 2007.

METHODS

The search methods used in the current version differ compared to the previously published guideline. Literature searches were conducted using standardized MeSH terms from the National Library of Medicine PUBMED database list of search terms. The following terms comprised the standard baseline search terms for all topics and were connected with the logical 'OR' connector--Extracorporeal circulation (MeSH number E04.292), cardiovascular surgical procedures (MeSH number E04.100), and vascular diseases (MeSH number C14.907). Use of these broad search terms allowed specific topics to be added to the search with the logical 'AND' connector.

RESULTS

In this 2011 guideline update, areas of major revision include: 1) management of dual anti-platelet therapy before operation, 2) use of drugs that augment red blood cell volume or limit blood loss, 3) use of blood derivatives including fresh frozen plasma, Factor XIII, leukoreduced red blood cells, platelet plasmapheresis, recombinant Factor VII, antithrombin III, and Factor IX concentrates, 4) changes in management of blood salvage, 5) use of minimally invasive procedures to limit perioperative bleeding and blood transfusion, 6) recommendations for blood conservation related to extracorporeal membrane oxygenation and cardiopulmonary perfusion, 7) use of topical hemostatic agents, and 8) new insights into the value of team interventions in blood management.

CONCLUSIONS

Much has changed since the previously published 2007 STS blood management guidelines and this document contains new and revised recommendations.

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

Background:

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

Case:

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

Conclusions:

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

Clinical review: Prothrombin complex concentrates--evaluation of safety and thrombogenicity

Prothrombin complex concentrates (PCCs) are used mainly for emergency reversal of vitamin K antagonist therapy. Historically, the major drawback with PCCs has been the risk of thrombotic complications. The aims of the present review are to examine thrombotic complications reported with PCCs, and to compare the safety of PCCs with human fresh frozen plasma. The risk of thrombotic complications may be increased by underlying disease, high or frequent PCC dosing, and poorly balanced PCC constituents. The causes of PCC thrombogenicity remain uncertain but accumulating evidence indicates the importance of factor II (prothrombin). With the inclusion of coagulation inhibitors and other manufacturing improvements, today's PCCs may be considered safer than earlier products. PCCs may be considered preferable to fresh frozen plasma for emergency anticoagulant reversal, and this is reflected in the latest British and American guidelines. Care should be taken to avoid excessive substitution with prothrombin, however, and accurate monitoring of patients' coagulation status may allow thrombotic risk to be reduced. The risk of a thrombotic complication due to treatment with PCCs should be weighed against the need for rapid and effective correction of coagulopathy.

Activated prothrombin complex concentrate factor VIII inhibitor bypassing activity (FEIBA) for the reversal of warfarin-induced coagulopathy

Aims

The purpose of this study was to evaluate the effectiveness of a new, fixed, yet individualized dosing regimen of activated prothrombin complex concentrate factor VIII inhibitor bypassing activity (FEIBA) for warfarin reversal in the setting of a life-threatening bleeding in a secondary care center.

Methods

In this report we present a retrospective chart review of 72 patients who received FEIBA and 69 patients who received fresh-frozen plasma (FFP) to reverse the effects of warfarin in a setting of a life-threatening bleeding. In the FEIBA cohort, patients received 500 units of FEIBA when the initial INR was <5 or 1,000 units of FEIBA when initial INR was ≥5.

Results

FEIBA administration resulted in lower subsequent INR when compared with FFP and shorter time elapsed from drug administration to an INR ≤1.4 when compared with FFP. No significant differences in survival or in the length of hospital stay were observed. A higher FEIBA dose induced a bigger decrease in INR than the lower dose. We observed five adverse events (7%) that could potentially be related to FEIBA administration.

Conclusions

The presented dosing regimen results in safe reversal of warfarin-induced coagulopathy, which appears to be faster and more profound than following FFP. Moreover, the use of activated PCC (FEIBA) does not appear to carry an increased risk of thrombotic events when compared to the rate reported for several non-activated PCC preparations.

Prothrombin complex concentrate vs fresh frozen plasma for reversal of dilutional coagulopathy in a porcine trauma model

Background

Fluid resuscitation following traumatic injury causes haemodilution and can contribute to coagulopathy. Coagulation factor replacement may be necessary to prevent bleeding complications of dilutional coagulopathy. Compared with fresh frozen plasma (FFP), prothrombin complex concentrate (PCC) may potentially offer a more rapid and effective means of normalizing coagulation factor levels.

Methods

In anaesthetized mildly hypothermic pigs, 65–70% of total blood volume was substituted in phases with hydroxyethyl starch and red cells. Animals were then treated with 15 ml kg⁻¹ isotonic saline placebo, 25 IU kg⁻¹ PCC, or 15 ml kg⁻¹ FFP. Immediately thereafter, either a standardized femur or spleen injury was inflicted, and coagulation function, including thrombin generation, and bleeding were assessed. An additional group received high-dose FFP (40 ml kg⁻¹) before femur injury.

Results

Haemodilution markedly prolonged prothrombin time and reduced peak thrombin generation. PCC, but not FFP, fully reversed those effects. Compared with 15 ml kg⁻¹ FFP, PCC shortened the time to haemostasis after either bone (P=0.001) or spleen (P=0.028) trauma and reduced the volume of blood lost (P<0.001 and P=0.015, respectively). Subsequent to bone injury, PCC also accelerated haemostasis (P=0.003) and diminished blood loss (P=0.006) vs 40 ml kg⁻¹ FFP.

Conclusions

PCC was effective in correcting dilutional coagulopathy and controlling bleeding in an in vivo large-animal trauma model. In light of its suitability for more rapid administration than FFP, PCC merits further investigation as a therapy for dilutional coagulopathy in trauma and surgery.