Spinal fusion with motor evoked potential monitoring using remimazolam in Alström syndrome

Abstract

Rationale: Alström syndrome is a rare genetic disorder characterized by obesity, diabetes mellitus, cardiomyopathy, and liver dysfunction. Further, scoliosis, a common symptom of Alström syndrome, often requires surgical intervention for functional impairments. Motor evoked potential (MEP) monitoring and other electrophysiological tests are essential when performing surgery for functional scoliosis. However, there are few reports on how to maintain general anesthesia in Alström syndrome. Here, we describe a patient with Alström syndrome who underwent surgery for scoliosis under general anesthesia with remimazolam and MEP monitoring.Patient concerns: A 17-year-old woman (height, 140 cm, weight, 64.5 kg) diagnosed with Alström syndrome was scheduled for a posterior spinal fusion for functional scoliosis. Other associated comorbidities of Alström syndrome present were dilated cardiomyopathy, type 2 diabetes mellitus, obesity (body mass index, 32.1 kg/m 2 ), amblyopia (light perception), and hearing impairment (speech awareness threshold 50 dBHL in each ear).Diagnoses, interventions, and outcomes: Posterior spinal fusion was planned for functional scoliosis. While investigating the dilated cardiomyopathy, transthoracic echocardiography showed global wall hypokinesis, with 45% left ventricular ejection fraction. The left ventricle was dilated, with left ventricular end-diastolic and end-systolic diameters of 55 and 42 mm, respectively. This finding along with the hypertriglyceridemia associated with Alström syndrome led us to conclude that propofol should be avoided. Thus, we induced general anesthesia using remimazolam. MEP monitoring was performed, and the patient experienced no motor impairments during the surgery.Lessons: Myocardial and hepatic dysfunction determine the prognosis of patients with Alström syndrome. Thus, anesthesia that preserves liver function should be selected in such cases. In patients with hypertriglyceridemia, propofol should be avoided, and using remimazolam, an ultrashort-acting benzodiazepine, may be appropriate. In this case, reviewing the Patient State Index with SedLine allowed us to perform MEP monitoring uneventfully, and the posterior spinal fusion was completed without any motor impairment.Abbreviations: MEP = motor evoked potential, PSi = Patient State Index.

Successful recording of direct cortical motor-evoked potential from a pediatric patient under remimazolam anesthesia: a case report

“…The EEG effects of benzodiazepines are predominantly a monotonic beta activation, especially in frontal areas, and these effects map to higher EEG-derived indices to estimate the anesthesia depth [ 23 ]. In contrast to the current pediatric case, previous tc-MEP reports of young and elderly patients showed that relatively higher remimazolam infusion rates were required for successful MEP recording [ 6 , 7 ]. In neurosurgery, stimulating intensities should be minimized to the least possible extent to circumvent false-positive signals that result from the stimuli reaching the skull base [ 16 ]; this is the most significant difference from tc-MEP, which is frequently used in spine surgery.…”

“…Although no connection between propofol allergy and egg, soy, or peanut allergies were found in adults [ 3 ], it is still unclear whether propofol administration is safe in children allergic to certain foodstuffs [ 4 ]. Remimazolam, a short-acting benzodiazepine characterized by metabolism independent of organ function [ 5 ], was proposed as an alternative to propofol for spine surgeries in young and elderly patients who require intraoperative transcranial MEP (tc-MEP) recordings [ 6 , 7 ]. This study presents a pediatric case with egg hypersensitivity whose direct cortical MEP (dc-MEP) was successfully recorded under remimazolam anesthesia, instead of propofol.…”

Clinical Application and Research Progress of Remimazolam for Pediatric Patients

“…Research has shown that varying the administration rate of remimazolam from 0.5 mg/kg/h to 1.0 mg/kg/h has no effect on the MEP amplitude. 28 In addition, Kamata et al 29 showed that remimazolam could be used as an alternative sedative agent to propofol for MEP monitoring in neurosurgery, even for immature toddlers with neurodevelopment. Inhalation anaesthetics or a prolonged infusion of propofol will reduce the capacity for fatty acid utilization and mitochondrial activity, and thus increase the risk of rhabdomyolysis.…”

The Role of Remimazolam in Neurosurgery and in Patients With Neurological Diseases: A Narrative Review

“…In another case report, a patient with Alstrom syndrome, a rare genetic disorder characterized by dilated cardiomyopathy, liver dysfunction, and scoliosis, underwent posterior spinal fusion and successful motor evoked potential monitoring with remimazolam 0.5 mg/kg/h for maintenance of general anesthesia. 27 A separate case report by Kondo et al 28 reported 2 patients undergoing spine surgery with general anesthesia maintained with remimazolam infusions. The effects on motor evoked potential waveforms in both patients were compared at different points, including baseline recordings, during laminoplasty, at the end of the procedure, and at escalating remimazolam infusions rates (0.5 up to 1.5 mg/kg/ h).…”

“…In another case report, a patient with Alstrom syndrome, a rare genetic disorder characterized by dilated cardiomyopathy, liver dysfunction, and scoliosis, underwent posterior spinal fusion and successful motor evoked potential monitoring with remimazolam 0.5 mg/kg/h for maintenance of general anesthesia 27 . A separate case report by Kondo et al 28 reported 2 patients undergoing spine surgery with general anesthesia maintained with remimazolam infusions.…”