The anticoagulated parturient.

Neuraxial analgesia and anesthesia are 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 and this is especially true in patients with thrombocytopenia and those receiving anticoagulant medication. 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. The purpose of this article is to review the role of platelets in the coagulation process, the laboratory tests available to test platelet function, and to provide recommendations as to the lowest platelet count that is acceptable for neuraxial anesthesia. In addition, an increasing number of patients are receiving anticoagulant medications during pregnancy and low molecular weight heparin (LMWH) is one of these agents. The role of LMWH during pregnancy and its implications for labor analgesia will also be discussed.