Abstract
orthostatic intolerance, TBI, traumatic brain injury
HEART, AUTONOMIC DYSFUNCTION
Patients with severe traumatic brain injury (TBI) may have autonomic dysfunction, one manifestation of which is orthostatic intolerance. This potentially impairs physical rehabilitation. However, the exact mechanisms remain elusive. In 30 patients participating in a trial of early tilt training versus standard care and 15 healthy volunteers, 5‐min electrocardiography was recorded in the supine position and during 70° head‐up tilt. Heart rate variability was analyzed by the low‐ and high‐frequency (LF and HF) power, the LF–HF ratio, the total power, the ratio of the standard deviation of normal‐to‐normal intervals (SDNN), the root mean square of successive differences (RMSSD), the detrended fluctuations, and sample entropy. In patients in the upright compared to the supine position, SDNN (Autonomic regulation of heart rate during mobilization from the supine to the upright position in patients with severe traumatic brain injury. Regulation may be blunted during early mobilization.
