Letters to the Editor: Letters & Announcements
To the Editor:
In a recent article describing the use of fondaparinux after major orthopedic surgery, Singelyn et al.1 chose a 48 h window between the last administration of fondaparinux and the removal of the epidural or the lumbar plexus catheters. In our practice, the removal of a perineural catheter in patients receiving thromboprophyalxis, is significantly different than that advocated by the authors of this article. Based on 11 yr experience with perineural catheters and all classes of anticoagulants including enoxaparin and fondaparinux, our position is that as long as the anticoagulant is used for thromboprophylaxis we do not concern ourselves with the nature of the anticoagulant being administered nor do we concern ourselves with the timing of the anticoagulant or the timing of its administration.2 In other words, perineural catheters are removed, based on the patient’s need of infusion of local anesthetics, not the timing of the fondaparinux administration. In a recently published series of almost 7000 blocks performed in orthopedic patients receiving postoperative thromboprophylaxis including 193 patients with lumbar plexus catheters and in whom fondaparinux was being used.3 No serious bleeding complications occurred following removal of the perineural catheter.
We agree that the question raised by the authors is very important but unless proven otherwise we believe that there is no reason for a 48 h interval. The length of stay of patients undergoing conventional joint replacement is 3.5 days. If we follow Singelyn et al.'s1 recommendation, patients receiving fondaparinux could either not benefit from lumbar plexus block (which is our standard of care for total hip replacement) or would not receive more than a couple of doses or would have a longer stay in the hospital to satisfy the required 48 h interval.
Patients undergoing total hip replacement are not only at risk for deep vein thrombosis and pulmonary embolism immediately after the surgery but for an extended period of time. In this regard, fondaparinux has been shown to be very effective in preventing such a complication4 and the use of a lumbar plexus block represents an important addition to the management of postoperative pain.5 In the absence of clinical evidence that a 48 h interval is required for safety reasons, we recommend the use of both fondaparinux and lumbar plexus blocks following total hip replacement. Finally, I do agree that more reports are needed to determine the safest approach to manage continuous deep blocks in patients receiving effective thromboprophylaxis, especially in patients with chronic and liver failure and extreme low weight which have been shown to increase the risk of hematoma following thromboprophylaxis.
In addition, although, we have not made allowance for chronic or liver failure and extreme low weight in our practice, some consideration may be given for these extreme medical conditions when managing the removal of deep continuous nerve block in patients receiving thromboprophylaxis.
Jacques E. Chelly, MD, PhD, MBA
Department of Anesthesiology
Orthopaedic Anesthesia and Acute Interventional Perioperative Pain Divisions
University of Pittsburgh Medical Center
UPMC Presbyterian-Shadyside Hospital
1. Singelyn FJ, Verheyen CCP, Piovella F, Van Aken HK, Rosencher N; EXPERT Study Investigators. The Safety and Efficacy of Extended Thromboprophylaxis with Fondaparinux After Major Orthopedic Surgery of the Lower Limb With or Without a Neuraxial or Deep Peripheral Nerve Catheter: The EXPERT Study. Anesth Analg 2007;105:1540–7
2. Chelly JE, Schilling D. Thromboprophylaxis and peripheral nerve blocks in patients undergoing joint arthroplasty and hip fracture surgery. J Arthroplasty 2008; 23:350–4
3. Hantler CB, Despotis GJ, Sinha R, Chelly JE. Guidelines and alternatives for neuraxial anesthesia and venous thromboembolism prophylaxis in major orthopaedic surgery. J Arthroplasty 2004;19:1004–16
4. Geerts WH, Pineo GF, Heit JA, Bergqvist D, Lassen MR, Colwell CW, Ray JG. Prevention of venous thromboembolism: the Seventh ACCP Conference of Antithrombotic and Thrombolytic Therapy. Chest 2004;126(3 suppl):338S–400S
5. Horlocker TT, Kopp SL, Pagnano MW, Hebl JR. Analgesia for total hip and knee arthroplasty: a multimodal pathway featuring peripheral nerve blocks. J Am Acad Orthop Surg 2006;14:126–35