General anesthesia for patient with Fahr's syndrome: A case report

Fahr's syndrome (FS) is a rare neurological and psychiatric disorder characterized by bilateral brain calcifications when a secondary cause of the calcification is found.

A 53-year-old female patient diagnosed with FS for laminectomy because of ossification of posterior longitudinal ligament. She had a history of generalized tonic-clonic (GTC) seizure and medication with anticonvulsant drugs. She had gait disturbance, spasticity, bradykinesia, and diffuse calcifications in the basal ganglia, thalamus, cerebellum, and cerebral hemispheres on the brain computed tomography. On the preoperative examination, the serum and ionized calcium (Ca) were decreased to 3.7 and 2.22 mg/dL. Hypomagnesemia is combined with hypocalcemia. Furthermore, the level of parathyroid hormone was decreased to 2.18 pg/mL.

Due to the radiologic findings and laboratory test results, she was diagnosed with FS with primary hypoparathyroidism.

The Ca and magnesium (Mg) had been corrected before surgery but the electrolytes revealed low level at the intraoperative period. The 300 mg of calcium chloride was administered at 2 times and 1200 mg of it were infused for 1 hour during intraoperative periods. In addition, total 4 g of Mg sulfate intravenously administered. We used rocuronium as a neuromuscular block and checked neuromuscular function by train-of-four monitoring.

Residual neuromuscular blockade was reversed with pyridostigmine and her muscle power completely recovered. The patient was extubated successfully and no unpredictable events occurred. On the day following transfer, serum electrolytes remained low, and although Ca was continuously supplied, serum Ca did not recover to a normal level. The patient was medicated with anticonvulsant drugs but experienced GTC seizure 2 weeks after surgery.

We presume that the pathophysiology of FS was related to primary hypoparathyroidism and hypomagnesemia. FS raises concerns associated with neuromuscular problems, spasticity, and seizure, and concerns of hypotension, heart failure, cardiac arrhythmia, and cerebrovascular attack during perioperative periods, among anesthesiologists because of hypocalcemia and vessel calcification. During the perioperative period, Ca levels should be closely monitored, and titrated Ca replacement therapy is recommended. The simultaneous correction of hypomagnesemia is of considerable importance when correcting hypocalcemia.