Total joint replacement in patients with inhibitors

Over two decades of orthopaedic surgery in patients with inhibitors-Quantifying the complication of bleeding

Patients with haemophilia who have developed inhibitors against factor VIII (FVIII) or factor IX present a significant concern to those surgeons who operate on them. The evidence base for bypassing agents such as recombinant factor VIIa and activated prothrombin complex concentrate has amassed over several decades. The literature is open to positive interpretation on the successful use of these agents in the treatment of inhibitor-positive patients. However, there are equally persistent concerns amongst surgeons, in particular orthopaedic surgeons, regarding the high complication rate of bleeding. To explore and quantify this concern, we present a literature review spanning two decades of publications on haemophilia patients with inhibitors undergoing orthopaedic surgery. Irrespective of the progress made with haemostatic protocols, trepidation on embarking on surgery is valid. The high risk of bleeding is a function of the inherent complexity of the disease and rightfully translates into difficulties in its management. Combined with the prospect of orthopaedic surgery, those involved in the care of such patients are justified in their continued anxiety and diligence when considering the benefits in quality of life against the prevalent complications.

Continuous infusion of recombinant activated factor VII: a review of data in congenital hemophilia with inhibitors and congenital factor VII deficiency

Introduction

Continuous infusion (CI) of clotting factors as a replacement therapy for perioperative hemostatic protection has been performed for many years, including with factors VIII and IX and recombinant activated factor VII (rFVIIa). This approach provides steady factor levels without requiring frequent administration of bolus doses.

Aim

To review safety, efficacy, and dosing data regarding CI of rFVIIa for hemostatic management of patients with congenital hemophilia with inhibitors (CHwI) or congenital factor VII deficiency (C7D).

Materials and methods

A literature review identified instances of CI of rFVIIa in patients with CHwI or C7D undergoing surgery or experiencing bleeding episodes. Data regarding safety, efficacy, and dosing were extracted.

Results

The safety and efficacy of 50 mcg/kg/h CI of rFVIIa following a 90 mcg/kg bolus injection, vs a standard bolus injection regimen, was reported for 24 patients with CHwI undergoing elective surgery in an open-label, randomized, Phase III trial. Efficacy was similar between CI and bolus injection groups at all postoperative time points assessed. Additionally, a postmarketing surveillance study reported effective (80%) and partially effective (20%) CI of rFVIIa in a Japanese cohort of ten patients with CHwI who underwent 15 surgical procedures. Finally, the safety and dosing of rFVIIa CI in 193 and 26 patients with CHwI and C7D, respectively, were reported in 11 prospective studies, 10 retrospective studies, and 30 case reports. No unexpected safety findings were reported.

Conclusion

rFVIIa CI has been performed safely and effectively in patients with CHwI and C7D undergoing surgery and during bleeding episodes in patients with CHwI.

Recommendations on multidisciplinary management of elective surgery in people with haemophilia

Planning and undertaking elective surgery in people with haemophilia (PWH) is most effective with the involvement of a specialist and experienced multidisciplinary team (MDT) at a haemophilia treatment centre. However, despite extensive best practice guidelines for surgery in PWH, there may exist a gap between guidelines and practical application. For this consensus review, an expert multidisciplinary panel comprising surgeons, haematologists, nurses, physiotherapists and a dental expert was assembled to develop practical approaches to implement the principles of multidisciplinary management of elective surgery for PWH. Careful preoperative planning is paramount for successful elective surgery, including dental examinations, physical assessment and prehabilitation, laboratory testing and the development of haemostasis and pain management plans. A coordinator may be appointed from the MDT to ensure that critical tasks are performed and milestones met to enable surgery to proceed. At all stages, the patient and their parent/caregiver, where appropriate, should be consulted to ensure that their expectations and functional goals are realistic and can be achieved. The planning phase should ensure that surgery proceeds without incident, but the surgical team should be ready to handle unanticipated events. Similarly, the broader MDT must be made aware of events in surgery that may require postoperative plans to be changed. Postoperative rehabilitation should begin soon after surgery, with attention paid to management of haemostasis and pain. Surgery in patients with inhibitors requires even more careful preparation and should only be undertaken by an MDT experienced in this area, at a specialized haemophilia treatment centre with a comprehensive care model.

Successful management of total knee replacement in a high responder hemophilia patient with a history of inhibitor

The development of inhibitors against administered clotting factors may render replacement therapy ineffective for some hemophilia patients. Such patients are therefore at the highest risk of developing arthropathy. Elective orthopedic surgery (EOS) in hemophilic patients having such inhibitors remains a rare, expensive, and difficult surgery, whose management represents a significant challenge. We report the case of a 35-year-old man with a severe form of hemophilia A (factor VIII < 1%), who was suffering from repetitive spontaneous hemarthrosis, especially in his knee joints that had consequently become more susceptible to bleeding. The patient had a history of high levels of factor VIII inhibitor (> 5.0 Bethesda Unit [BU]/ml) as shown by the factor VIII inhibitor assay; therefore, we began treatment with factor VIIa for his mild-to-moderate bleeding (90 µg/kg intravenous bolus injections). The interval between injections varied with the severity of the hemorrhage in each bleeding episode. The inhibitor level reduced to 3.1 BU/ml after three months, to 1.6 BU/ml after six months, and disappeared completely after one year of treatment. We administered factor VIII at a dose of 50 IU/kg every eight hours during the first three post-operative days, then continued administration with a dose of 40 IU/kg every 12 hours for another four days, and observed a very good response to treatment with no bleeding. Recombinant activated factor VII (rFVIIa) is not an inhibitor-removal strategy, but an inhibitor-bypassing product. However, in our patient, the treatment of mild-to-moderate bleeding with short-term use of rFVIIa and no exposure to factor VIII caused a gradual reduction in the inhibitor level over a period of 1 year.

Comprehensive care of the patient with haemophilia and inhibitors undergoing surgery: practical aspects

Congenital haemophilia is a rare and complex condition for which dedicated specialized and comprehensive care has produced measurable improvements in clinical outcomes and advances in patient management. Among these advances is the ability to safely perform surgery in patients with inhibitor antibodies to factors VIII and IX, in whom all but the most necessary of surgeries were once avoided due to the risk for uncontrollable bleeding due to ineffectiveness of replacement therapy. Nevertheless, surgery continues to pose a major challenge in this relatively rare group of patients because of significantly higher costs than in patients without inhibitors, as well as a high risk for bleeding and other complications. Because of the concentration of expertise and experience, it is recommended that any surgery in patients with haemophilia and inhibitors be planned in conjunction with a haemophilia treatment centre (HTC) and performed in a hospital that incorporates a HTC. Coordinated, standard pre-, intra- and postoperative assessments and planning are intended to optimize surgical outcome and utilization of resources, including costly factor concentrates and other haemostatic agents, while minimizing the risk for bleeding and other adverse consequences both during and after surgery. This article will review the special considerations for patients with inhibitors as they prepare for and move through surgery and recovery, with an emphasis on the roles and responsibilities of individual members of the multidisciplinary team in facilitating this process.

Elective orthopaedic surgery for haemophilia patients with inhibitors: single centre experience of 40 procedures and review of the literature

With the introduction of safe and effective factor VIII/IX-bypassing agents--recombinant activated factor VII (rFVIIa) and plasma-derived activated prothrombin complex concentrates (pd-APCC)--elective orthopaedic surgery (EOS) is a viable option for haemophilia patients with inhibitors. We report a series of patients with haemophilia and inhibitors undergoing EOS between 1997 and 2008 using bypassing agents to provide haemostatic cover. All inhibitor patients undergoing EOS and receiving rFVIIa, plasma-derived prothrombin complex concentrates (pd-PCC) or pd-APCC as haemostatic cover were included. Patients were operated on by the same surgeon and were managed by the same haemophilia treatment centre. Forty procedures (25 minor and 15 major) were conducted in 18 patients. Twenty-one minor cases were covered using rFVIIa, three with pd-PCC, and one with pd-APCC; all major cases were covered using rFVIIa. Bleeding was no greater than expected compared with a non-haemophilic population in all 25 minor procedures. In the major procedure group, there was no excessive bleeding in 40% of cases (6/15) and bleeding completely stopped in response to rFVIIa. For the remaining nine cases, bleeding response to rFVIIa was described as 'markedly decreased' or 'decreased' in 4/15 cases and 'unchanged' in 5/15 cases. Overall, efficacy of rFVIIa, based on final patient outcome, was 85%. One death occurred as a result of sepsis secondary to necrotizing fasciitis. Good control of haemostasis can be achieved with bypassing agents in haemophilia patients with inhibitors undergoing minor EOS; rFVIIa was used as an effective bypassing agent, enabling EOS in patients undergoing minor and major procedures.

Evidence supporting the use of recombinant activated factor VII in congenital bleeding disorders

BACKGROUND

Recombinant activated factor VII (rFVIIa, NovoSeven) was introduced in 1996 for the treatment of hemophilic patients with antibodies against coagulation factor VIII or IX.

OBJECTIVE

To review the evidence supporting the use of rFVIIa for the treatment of patients with congenital bleeding disorders.

PATIENTS AND METHODS

English-language databases were searched in September 2009 for reports of randomized controlled trials (RCTs) evaluating the ability of rFVIIa to restore hemostasis in patients with congenital bleeding disorders.

RESULTS

Eight RCTs involving 256 hemophilic patients with antibodies against coagulation factors, also known as inhibitors, were identified. The evidence supporting the use of rFVIIa in these patients was weak with regard to dose, clinical setting, mode of administration, efficacy, and adverse events, given the limited sample size of each RCT and the heterogeneity of the studies.

CONCLUSION

The authors suggest that rFVIIa therapy in hemophilic patients with inhibitors should be based on the individual's ability to generate thrombin and form a clot, and not on the patient's weight alone. Therefore, assays for thrombin generation, such as whole-blood thromboelastography, have the potential to significantly improve the treatment of these patients.

Controversies and challenges in elective orthopedic surgery in patients with hemophilia and inhibitors

Until recently, orthopedic surgery was strongly contraindicated in patients with hemophilia and inhibitors. However, recent advances in our knowledge of bypassing agents (particularly recombinant activated factor VII [rFVIIa]) that provide effective surgical hemostasis have allowed us to successfully perform major orthopedic procedures in these patients. Adequate hemostasis during surgery and postoperative rehabilitation is crucial, as development of a wound hematoma may jeopardize long-term outcomes. It also should be noted that success depends not only on appropriate drug therapy but also on preoperative preparations and adequate perioperative surveillance. Preoperative assessment of vascular status is very important, and strong motivation--on the part of the patient, the surgeon, and the hematologist--is needed to ensure a satisfactory result. Although inhibitor patients undergoing surgery face a higher risk of bleeding and other complications than their non-inhibitor counterparts, outcomes are generally good if a multidisciplinary team approach is applied.