///2016 Abstract Details
2016 Abstract Details2019-07-15T10:10:51-05:00

An Unusual Cause of Thrombocytopenia in a Patient Undergoing Fetal Therapy

Abstract Number: SU-59
Abstract Type: Case Report/Case Series

Courtney G. Masear M.D.1 ; Sharon C. Reale M.D.2; Michael A. Purvin M.D.3; Karen Lindeman M.D.4

Introduction

Mid-gestation minimally invasive fetal procedures are becoming increasingly common. Although frequently performed with local anesthetic infiltration of the abdominal wall, procedures involving prolonged or more intense manipulation may compromise maternal comfort and necessitate other techniques such as epidural anesthesia. We present a patient with thrombocytopenia for whom epidural anesthesia was requested.

Case Discussion

A 39 year old at 19.1 weeks with a mono-di twin pregnancy presented with Stage 3 twin-to-twin transfusion syndrome for an endoscopic laser ablation. The surgical team requested epidural anesthesia. The patient denied symptoms of bleeding or bruising or a history of hematologic disease.

The day of presentation platelet count was 88,000 per mcL. An additional sample was sent and platelets were unable to be quantified as platelets were in clumps. A thromboelastogram was within normal limits.

An L3-4 epidural catheter was placed and was utilized intraoperatively. Postoperatively, the catheter remained in place for planned cerclage. The day of planned cerclage, platelets were again in clumps. Repeat platelet count in a citrate tube was 42,000 per mcL. Repeat showed a count of 62,000 per mcL. Hematology consult was obtained.

Workup included a platelet count in a heparinized tube, which revealed clumping. A peripheral smear was reviewed, with an estimated platelet count of 200-300,000 per mcL. The patient was diagnosed with pseudothrombocytopenia. Cerclage was performed and then her epidural catheter was removed without adverse consequence.

Discussion

Pseudothrombocytopenia is an in vitro phenomenon that has been reported in 0.1-0.2% of hospitalized patients and 15-17% of outpatients evaluated for isolated thrombocytopenia(1, 2). Thus, it has obvious implications for the obstetric population desiring neuraxial anesthesia.

Pseudothrombocytopenia is caused by anti-platelet antibodies that react with platelets in blood anticoagulated with calcium chelating agents, most commonly EDTA. The diagnosis can be confirmed with microscopic examination(3). Rarely, as with our patient, it can also be seen with citrate and heparin(4). It has not been found to have pathological significance and has not been associated with age, sex, comorbidities, or drugs(5). Given that the thrombocytopenia is an in vitro, not in vivo phenomenon, parturients can safely receive neuraxial anesthesia.

References

1. Cohen, et al. Haematologia 2000,30(2):117–121.

2. Vicari, et al. Scand J Clin Lab Invest 1988,48(6):537–542.

3. Chia, et al. Blood 2011,117(16):4168.

4. Bizzaro N. In Platelets. Volume. 3rd edition. Elsevier, Amsterdam: Academic Press; 2013:989–997.

5. Bizzaro N. Am J Hematol 1995,50(2):103–109.

SOAP 2016