Preoperative state of autonomic regulation in patients with adolescent idiopathic scoliosis

Objective. To analyze the state of autonomic regulation of the heart rate in patients with adolescent idiopathic scoliosis before the upcoming surgical treatment of spinal deformity.Material and Methods. The study included 30 patients with adolescent idiopathic scoliosis who were admitted for surgical treatment from January to April 2021. There were 28 female and 2 male patients. The heart rate variability (HRV) registration was carried out on the VNS-micro vegetotester, with Poly-Spectrum.NET software, Neurosoft (Russia). The study was conducted for 5 minutes in the supine position and for 5 minutes after the active orthostatic test. Temporal and spectral indicators of heart rate were analyzed.Results. When analyzing HRV at rest, an increase in the temporal indicators of the heart rate and the power of high-frequency wave oscillations was recorded, which indicates both an increased activity of autonomic regulation in general and the predominance of the regulatory influence o of the parasympathetic division of the autonomic nervous system. A decrease in all spectral components during an active orthostatic test and an increase in stress index values by 3.5 times indicate  a significant stress of regulatory systems.Conclusion. Analysis of HRV in patients with adolescent idiopathic scoliosis at rest revealed increased autonomic activity with a predominant effect of the parasympathetic division of the autonomic nervous system. The state of exercise-induced energy deficit, registered after an active orthostatic test, indicates a significant preoperative stress of the regulatory systems and refers this category of patients to a group of increased risk of complications associated with hemodynamic instability.