Epidural Hematoma after the Use of Subcutaneous Unfractionated Heparin and History of Epidural Tumor

摘要

The patient was a 66-year-old male with a history of renal cell carcinoma with metastasis to the L2, L3, and L4 vertebral bodies scheduled for a radical nephrectomy and adrenalectomy. Prior to surgery the patient had undergone 10 radiation treatments for the vertebral metastasis. Patient medications included colace, prednisone, ibuprofen (taken 4 days prior to procedure), sunitinib, hydrocodone, benazepril, nexium, rosuvastatin, allopurinol, and azor. Physical exam prior to surgery was normal with no focal findings. Laboratory values were within normal limits with a platelet count of 286. General anesthesia was planned with a pre-operative thoracic epidural for postoperative analgesia. The epidural was placed at the T9-T10 level without complication. Adequate pain control was present post operatively and the epidural was discontinued on post-operative day 3. At that time the patient was noted to have numbness over the bilateral lower extremities and decreased strength. Heparin 5000 units subcutaneous had been given 12 hours prior to discontinuation of the epidural. The patient was afebrile, hemoglobin was 7, white blood cell count was 9.7, and platelets were 166 at time of epidural removal. Subcutaneous heparin was restarted 6 hours after catheter removal. The anesthesia acute pain service was contacted by the primary service 25 hours after discontinuation of the epidural catheter regarding complaints of persistentbilateral lower extremity weakness and sensory loss. An magnetic resonance image (MRI) revealeda focus posterior to the spinal cord at the T10/T11 interspace likely representing a hematoma. A high intensity T2 signal within the central spinal cord at T10/T11 was also observed;likely a vascular infarct. The patient was immediately scheduled for a T9-T10 laminectomy and evacuation of the epidural hematoma. No significant abnormalities were noted in coagulation studies prior to surgery. The patient was discharged on post-operative day 20 with no neurologic deficits.An epidural hematoma is rare with an estimated occurrence of <1 in 150,000[1]. Issues related to anticoagulation therapy are involved in 25% - 30% of cases. The utilization of three times daily dosed (TID) heparin could have played a role in the development of this complication in the present case. Other contributing factors may have been chemotherapy and radiation therapy. These treatments are quite damaging to bone marrow and may cause severe marrow suppression thereby suppressing the function and number of platelets. Cancer cells are also capable of producing local cell signals which can initiate new blood vessel growth and proliferation[2]. This can also lead to blood vessels that are defective and leaky at the level of the endothelium. Increasing the number of fragile blood vessels may easily predispose this patient to laceration and shearing of blood vessels during epidural placement.