///2015 Abstract Details
2015 Abstract Details2019-08-02T16:54:43-06:00

Neuraxial Anesthesia in a Parturient on Antithrombin Concentrate

Abstract Number: F-24
Abstract Type: Case Report/Case Series

Ellen H Webb MD1 ; Baskar Rajala MBBS2

Introduction: Antithrombin (AT) III deficiency is a rare disease affecting 1 in 600-1000 individuals. The high risk of thromboembolism (VTE) in pregnant patients with ATIII deficiency has prompted many obstetricians to recommend anticoagulation throughout pregnancy. However, current ASRA guidelines suggest holding treatment dose LMWH from 24 hours before placing an epidural to 4 hours following removal, a window which could pose a significant VTE risk. A potential alternative to LMWH is AT concentrate which has been shown in initial studies to be safe for use when anticoagulation is contraindicated.

Case Details: A 31yo G3P2 with a history of ATIII deficiency was admitted at 38 weeks for induction of labor. During her pregnancy she was anticoagulated with 120mg of LMWH BID, which had been held 24 hours prior to admission. On admission, baseline studies revealed AT activity of 61% (normal = 80-120%). She then received 2100 Units IV bolus of AT concentrate which increased AT activity to 94%. Induction of labor continued and 24 hours after admission she requested epidural placement. At that time, repeat laboratory studies confirmed a normal PTT and INR with AT activity of 80%. A lumbar epidural catheter was then placed without difficulty. A second bolus of AT concentrate was administered 24 hours after the first dose. Subsequently the decision was made to proceed to cesarean delivery due to arrest of descent. The existing epidural was used to obtain an adequate surgical level of anesthesia and the intraoperative course was uneventful. The epidural catheter was removed immediately postoperatively and subsequent follow-up did not reveal any neurologic changes or other concerning symptoms. LMWH was restarted the following day with plans to follow-up with outpatient hematology.

Discussion: Few case studies exist in the literature describing the use of neuraxial anesthesia in a patient receiving AT concentrate. Theoretically, the use of AT concentrate restores the patient to a normal coagulation state by correcting their innate deficiency, reducing the risk of VTE while posing no increased risk from neuraxial anesthesia. Induction of labor should be a coordinated effort between anesthesia, obstetrics, and hematology such that epidural placement would be requested at least 24 hours following the last dose of LMWH but following the initiation of AT concentrate so as to avoid either supratherapeutic or subtherapeutic anticoagulation at the time of epidural placement. While there have been no reported cases of significant effects from “overshooting” anticoagulation with AT concentrates, there is still fairly limited pooled experience with this treatment and a low baseline occurrence of such complications. Further studies are needed to fully elucidate whether any increased risk exists in these patients.

References:

Pamnani, A. et al. (2010) Journal of Clinical Anesthesiology 22:450-453

Rogenhofer, N. et al. (2013) Annals of Hematology 93:385–392

SOAP 2015