Subarachnoid Block in a Patient with Essential Thrombocytemia

Abstract

To the Editor: Essential thrombocythemia is a myeloproliferative disorder characterized by overproduction and eventual failure of platelets in peripheral blood with high risk for thrombohemorrhagic complications (1). The use of spinal anesthesia in patients with essential thrombocythemia is controversial, as they may develop spinal hematomas that may produce spinal cord compression and paraplegia (2). We report our initial experience with lumbar spinal anesthesia administration to a patient with essential thrombocythemia. A 74-year-old man was scheduled for femoral-popliteal bypass surgery for severe rest pain and an ischemic ulcer on his right leg. Past history disclosed that the patient had been a smoker since adolescence and had diabetes mellitus and chronic obstructive pulmonary disease. He had ischemic symptoms of claudication in his lower limbs and had been treated with clopidrogel and enoxaparin. He was diagnosed with essential thrombocythemia. Laboratory analysis revealed a blood platelet count of 1,046,000/μL and the patient required cytoreductive therapy with hydroxyurea. He had been previously operated for cholecystectomy and reported having had a difficult airway management that required bronchofibroscopic intubation. Physical examination revealed a Mallampati IV class, obesity with short neck, Tiffeneau’s index of 50%. Chest radiographs showed trapped air signs. Preoperative blood tests were within normal limits, with a platelet count of 329,000/μL and normal aggregation tests. In the operating room, he was monitored with electrocardiogram, noninvasive blood pressure, and pulse oximetry. Supplemental oxygen was given via a nasal cannula. Spinal anesthesia was performed in the lateral position with a 26-gauge Whitacre needle placed between the L3-4 vertebral spaces using 2.5 mL hyperbaric bupivacaine 0.5% with fentanyl 10 μg. A T6 sensory level of anesthesia was obtained. An infrainguinal bypass with a prosthetic graft to the second right popliteal section was performed that lasted approximately 80 min. The patient was monitored closely during the postoperative period for early signs of spinal cord compression, but no neurological complications appeared. In agreement with other authors (3,4), we suggest that neuraxial block may be indicated in essential thrombocythemia patients only if preoperative platelet counts and aggregation tests are within the normal range. Joaquín García-Ferreira, MD Joaquín Hernández-Palazón, MD, PhD Antonio García-Candel, MD Teresa Verdú-Martínez, MD Department of Anaesthesia H. U. “Virgen de la Arrixaca” Murcia, Spain [email protected]