Monitoring of the Effectiveness of Intensive Care and Rehabilitation by Evaluating the Functional Activity of the Autonomic Nervous System in Patients with Brain Damage

Abstract

Purpose: evaluation of the clinical significance of parametric monitoring of the effectiveness of intensive care and rehabilitation based on the analysis of the functional state of the autonomous nervous system in patients with brain damage of different genesis.Materials and methods. The study included 66 patients on day 20—50 after the traumatic brain injury; anoxic damage; and stroke consequences. The isolation of clinical groups and subsequent analysis of clinical status is based on the analysis of the functional state of the autonomic nervous system based on the dynamics of the heart rate variability (HRV) parameters. Findings obtained in studies of 500 patients in the postoperative period with a 5-minute HRV were tested as normal and abnormal ANS parameters [1]. Parasympathetic hyperactivity was measured within the limits for SDNN (standard deviation of all normal-to-normal R-R intervals) > 41.5 ms; for rMSSD (root-meansquare of the successive normal sinus R-R interval difference) > 42.4 ms; for pNN50% (the percentage of interval differences in successive NN intervals greater than 50 ms (NN50) / total number of NN intervals) > 8.1%; for SI (Baevsky stress index, in normalized units) < 80 n. u.; for TP (total power of variance of all NN intervals) > 2000 ms2. Sympathetic hyperactivity was determined within the limits for following parameters: SDNN, < 4.54 ms; rMSSD, < 2.25 ms; pNN50%, < 0.109%; SI, > 900 n. u.; TP < 200 ms2. Normal HRV parameters were selected within the limits of the values for: SDNN [13.31-41.4ms]; rMSSD [5.78—42.3 ms]; pNN50% [0.110—8.1%]; SI [80—900 nu]; for TP [200—2000 ms2]. To verify the parasympathetic or sympathetic hyperactivity within these limits, 3 of 5 parameters were chosen [1].Results. Based on the dynamics of the HRV parameters before the intensive care and on days 30—60 of the intensive therapy and rehabilitation of patients with traumatic and non-traumatic brain injuries, 5 main clinical groups of patients were identified. Group 1 (n=27) consisted of patients with normal parameters of the ANS functional activity (both at the time of admission to the hospital and on the 30—60th day of the intensive therapy and rehabilitation). Group 2 (n=9) included patients with the baseline sympathetic hyperactivity of the ANS at admission to the intensive care unit and normal functional activity of the ANS on the 30—60th day of the intensive care and rehabilitation. Group 3 (n=8) included patients with baseline normal functional state of the ANS and the signs of sympathetic hyperactivity of the ANS on the 30—60th day of the intensive care and rehabilitation. Group 4 (n=15) consisted of patients with signs of sympathetic hyperactivity of the ANS both initially and on the 30—60th day of the intensive care and rehabilitation. Group 5 (n=7) included patients with signs of parasympathetic hyperactivity of the ANS (according to the parameters of HRV) both at baseline, at admission to the intensive care unit, and on the 30—60th day of the intensive care and rehabilitation.Conclusion: The normalization of HRV parameters is accompanied by patients’ recovery from the vegetative state and coma to minimal consciousness or normal consciousness; the index of disability rate decreases, the social reintegration grows, according to the DRS scale (M. Rappaport, 1982); dependence on mechanical ventilation reduces, and the muscle tone normalizes.

Keywords

• neuromonitoring
• heart rate variability
• sympathetic and parasympathetic hyperactivity
• craniocerebral trauma
• brain anoxia