Anesthetic Management of a Patient With Restless Legs Syndrome: A Case Report

Restless legs syndrome (RLS) is a neurological sensory disorder associated with sensory and motor symptoms that most commonly occur at night and during periods of rest. It is characterized by altered or abnormal sensations primarily in the legs and the urge to move the associated limbs. Perioperative procedures, including general anesthesia, can cause exacerbations of RLS. This is a case report of a suspected RLS exacerbation in a 22-year-old woman who had no formal diagnosis of RLS despite reporting symptoms that met all essential diagnostic criteria by the International RLS Study Group. Despite her previous diagnoses of dehydration induced-muscle pain or nocturnal cramps, we suspected her to have RLS. The patient underwent general anesthesia for a bilateral sagittal split ramus osteotomy using a combined inhalational and intravenous anesthetic technique with sevoflurane, propofol, remifentanil, and dexmedetomidine. After successful completion of the surgery and returning to the ward, she began moving her lower extremities and complaining of unpleasant sensations in both ankles. Bed rest exacerbated the suspected RLS symptoms despite a continuous infusion of dexmedetomidine. The RLS symptoms continued to worsen and spread to her upper extremities. After increasing the dexmedetomidine infusion from 0.2 to 0.4 μg/kg/h, almost all symptoms improved, and she slept for 3 hours. Upon awakening, the unpleasant sensations were completely relieved by walking and stretching. The patient was formally diagnosed with RLS by a neurologist after discharge. In this case, an infusion of dexmedetomidine was helpful in successfully managing a suspected exacerbation of RLS.

Muscle Stiffness and Cramps

Muscle stiffness as a nonspecific term means limited muscle mobility. Muscle and joint pain may be described as stiffness. Painful, sustained muscle cramps are usually associated with muscle stiffness. A careful history is paramount. Exercise-induced muscle cramps are usually myopathic (metabolic or mitochondrial myopathy) while resting, and nocturnal cramps are neurogenic [neuropathy, motor neuron disease (MND), etc.]. Metabolic cramps are electrically silent. Focal or generalized stiffness is typically seen in stiff person syndrome (SPS). Upper motor neuron (UMN) lesions are associated with spasticity and stiffness [hereditary spastic paraplegia (HSP), primary lateral sclerosis (PLS), myelopathies, etc.]. Painful cramps and fasciculation are important clues to peripheral nerve hyperexcitability disorder, which may also present with neuromyotonia. Not unusually, no cause is found for muscle cramps and stiffness. Symptomatic treatment frequently helps.

Muscle Stiffness and Cramps

Muscle stiffness is a nonspecific term meaning limited muscle mobility that is not due to weakness. It is opposite to flexibility. Muscle and joint pain may be described as stiffness. Painful sustained muscle cramps are usually associated with muscle stiffness. A careful history is paramount. Exercise-induced muscle cramps are usually myopathic (metabolic or mitochondrial myopathy), while resting and nocturnal cramps are neurogenic (neuropathy, motor neuron disease, etc). Metabolic cramps are electrically silent. Focal or generalized stiffness is typically seen in stiff person syndrome. Upper motor neuron lesions are associated with spasticity and stiffness (HSP, PLS, myelopathies, etc.). Painful cramps and fasciculations are important clues to peripheral nerve hyperexcitability disorder, which may also present with neuromyotonia. Not unusually, no cause is found for muscle cramps and stiffness. Symptomatic treatment frequently helps.