Thrombocytopenia and Low Molecular Weight Heparin in the Parturient: Implications for Neuraxial Anesthesia

Neuraxial analgesia is routinely administered to the parturient. A devastating, albeit rare, complication of neuraxial anesthesia is spinal or epidural hematoma, and primarily occurs in patients with disorders of hemostasis. A parturient with a clinically active coagulation disorder or someone with a history of easy bruising and/or bleeding is considered to have an absolute contraindication to regional anesthesia. However, many areas of controversy exist. The concern most anesthesiologists have regarding thrombocytopenia is determining the lowest platelet count at which it is still safe to perform a neuraxial anesthetic technique. In addition, an increasing number of women are receiving anticoagulant medications during pregnancy and low molecular weight heparin (LMWH) is a commonly used agent. The role of platelets in the coagulation process, the most common disorders in pregnancy that lead to thrombocytopenia, and the laboratory tests available to assess platelet function will be reviewed and practical recommendations provided as to the anesthetic management of the parturient with thrombocytopenia and one who is taking LMWH.