Key result
Exposure to sitting and lower body negative pressure (-20 mmHg) revealed blunted sympathetic and parasympathetic responses to gravitational stress in 21 bedridden patients versus 18 normal persons.
Why the study?
Does bedridden status with severe physical disability alter heart rate variability in response to orthostatic stress compared to normal persons?
Observational (n=39)
Does bedridden status with severe physical disability alter heart rate variability in response to orthostatic stress compared to normal persons?
Bedridden patients with severe physical disability exhibit significant autonomic nervous system dysfunction, characterized by blunted responses to gravitational stress or sympathetic/parasympathetic imbalance depending on their level of daily orthostatic stimuli.
Bedridden patients may have autonomic dysfunction from limited orthostatic stimuli; Level 4 data leaves open prospective trials on mobilization effects.
The change in power spectral density of heart rate variability (HRV) during sitting and to an exposure to lower body negative pressure of ‐20 mmHg was estimated in 21 bedridden patients with severe physical disability and in 18 normal persons in order to investigate the change in their autonomic activity and its subsequent effect upon cardiovascular regulation. From the power spectral density of the HRV, sympathetic activity was assessed by the ratio of low frequency power (0.02–0.15 Hz) to high frequency power (0.15–0.5 Hz). Parasympathetic activity was estimated from high frequency power normalized by total power (0.02–0.5 Hz). The results suggest that in patients who were supported in a sitting position for several activities of daily living (ADL) during a few hours each day, both the sympathetic and parasympathetic nervous system response to gravitational stress is blunted. The parasympathetic deconditioning is more pronounced and progressive. On the other hand, the fully bedridden patient who received no orthostatic stimuli from a daily posture change demonstrated an imbalance between sympathetic and parasympathetic activity. This may be indicative of severe autonomic nervous system dysfunction.
No takes yet. Share an insight, caveat, or question.
Mita et al. (1998) conducted an observational in Severe physical disability (bedridden) (n=39). Sitting and exposure to lower body negative pressure vs. Normal persons was evaluated on Change in power spectral density of heart rate variability (HRV). Exposure to sitting and lower body negative pressure (-20 mmHg) revealed blunted sympathetic and parasympathetic responses to gravitational stress in 21 bedridden patients versus 18 normal persons.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: