Anaesthetic implication of von hippel lindau disease

Abstract

Von Hippel Lindau disease is an inherited autosomal dominant disorder with predilection to develop characteristic tumors in the cerebellar hemispheres (capillary hemangioblastomas), retina, brain stem and spinal cord [1]. Cerebellar tumors occur in about 60% of the patients with Von Hippel Lindau disease and brain stem tumors in 14 to 50 %. Accessible lesions are removed surgically [2]. Although benign, these tumors can cause symptoms secondary to pressure or hemorrhage and may be associated with pheochromocytoma. This report describes the anesthetic management of a unique case of Von Hippel Lindau disease in which cerebellar and spinal lesions were not associated with any evidence of pheochromocytoma but posed a hypertensive problem during the surgery. Case Report A 21-year-old man presented with complaints of progressive weakness of right lower limb for 3 months and low backache of 2 months duration. He denied history of trauma. Clinical examination revealed a well-built individual, a heart rate of 80 beats per minute, blood pressure of 160/90 mm Hg, with numbness and wasting of muscles of right lower limb. He had grade 3 and 4 power in right and left lower limbs respectively, with tenderness in lumbar spine and paraspinal muscle spasm. Routine laboratory examination revealed a hemoglobin of 16.1 gm/dl and blood sugar of 84 mg/dl. His metabolic and renal parameters and chest radiograph were normal. Electrocardiogram showed normal sinus rhythm, with q waves in leads II, III and aVf. Ophthalmic examination revealed retinal angiomas, berry aneurysms and papilloedema. Magnetic resonance imaging and ultrasonography of abdomen revealed multiple hemangioblastomas and syrinx in brain, spine and multiple bilateral renal cysts. A diagnosis of Von Hippel Lindau disease was confirmed and patient prepared for surgery. Preoperatively he was managed with tab atenolol 50 mg OD, tab amlodipine 5 mg OD, tab alprazolam 0.25 mg HS, tab diamox BD, mannitol and glycerol for control of blood pressure and rise in intracranial pressure. A work up for pheochromocytoma with MIBG scan and VMA level estimation was negative. He was accepted for occipital craniotomy and spinal cyst excision in a single stage in ASA - Class III (hypertension, multi-organ hemangioblastomas and weakness of right lower limb limiting his mobility) under general anaesthesia. The patient was prepared preoperatively with tab diazepam 10 mg on the morning of surgery. In the operating room, the patient was placed in supine position and monitoring included ECG (3 lead), NIBP, pulse oximetry and intravenous access using a 16 G intravenous cannula. Under local analgesia a central venous catheter and left radial arterial line was established. During the placement of these invasive monitoring lines, the patient's blood pressure did not exceed 160/100 mm of Hg. He was administered metoprolol (2.5 mg), fentanyl (1.5 mg/kg), dexamethasone (8 mg) and ranitidine (50 mg) intravenously. Anaesthesia was induced with intravenous thiopentone sodium (300 mg) and maintained with nitrous oxide 50% and oxygen 50% with isoflurane 0.6% administered via a face mask. Vecuronium (6 mg) was used as muscle relaxant to facilitate endotracheal intubation. Lignocaine 100 mg was administered 90 seconds prior to intubation. Intubation with a size 8.5 mm internal diameter, cuffed, flexometallic endotracheal tube was smooth and atraumatic. The inhalational gas flow rates were reduced to low flows and anesthesia maintained with nitrous oxide 66% and oxygen 33% with isoflurane 0.5 to 1%. The patient was placed in prone position, avoiding any compression over the abdomen. To maintain smooth haemodynamics and to avoid surges of blood pressure rise, a nitroglycerine continuous infusion was started and titrated in accordance with blood pressure. A total of 1500 ml of lactated ringer, 500 ml of gelofusine (colloid) and 350 ml of blood was transfused. The total blood loss measured approximately 450 ml. Intraoperatively the blood pressure was maintained between 110/70 to 150/90 mm of mercury using nitroglycerine and heart rate between 70 to 80 per minute using metoprolol as infusion. Patient was administered 300 mg dilantin sodium in a slow normal saline drip for seizure prophylaxis. The surgery lasted for six hours and was uneventful, with successful removal of both the cranial and spinal lesions. Intraoperative arterial blood gas analysis was within acceptable limits. Analgesia was maintained with intravenous morphine in conventional doses intraoperatively. Ondansetron (4 mg) was given intravenously towards the end of procedure to prevent postoperative nausea and vomiting. The patient was reversed with neostigmine (50 mg/kg) and glycopyrrolate (10 mg/kg) intravenously and extubated on the table after prior administration of lignocaine (60 mg) intravenously to ablate the stress response. Postoperatively, he was intact neurologically and was shifted to ICU for further care and management. The post operative analgesia was maintained with diclofenac sodium 75 mg 8 hourly intramuscularly. The stay in ICU was uneventful and did not require any anti hypertensives. The patient was discharged with an advice for review after 6 months.