Pattern of autonomic dysfunction in time course of complex regional pain syndrome

Abstract

The objective of the present investigation was to describe and localize autonomic dysfunction in acute and chronic stages of complex regional pain syndrome (CRPS). Patients were investigated twice: the first investigation was performed as soon as diagnosis was established during the acute stage of CRPS and the second investigation was performed about 2 years later. Twenty-one patients completed the follow-up investigation. The median duration of CRPS was 5 (range 2-21) weeks at first investigation and 94 weeks (22-148) at follow-up. Skin temperature was recorded by thermography, sudomotor function was assessed by thermoregulatory sweat test (TST) and quantitative sudomotor axon reflex test (QSART). Skin temperature was warmer on the affected side at the first investigation (P< 0.001) and colder at follow-up (P < 0.02) compared with the contralateral limb. Sudomotor output was enhanced after both TST (P < 0.005) and QSART (P < 0.05) at the first investigation on the affected side. However, at follow-up, sweating after TST was still increased (P < 0.04) while QSART responses were not different between the affected and unaffected limbs. As compared to controls there was no statistically significant difference, neither in skin temperature nor sweating, neither on the affected nor on the unaffected side. In conclusion, the present investigation proved that vasomotor and sudomotor control are substantially altered in CRPS. In the acute stage vasomotor control is decreased in the affected limb whereas sudomotor function is enhanced. This may be the result of disturbances of thermoregulation, but different secondary peripheral mechanisms, concerning vasomotor and sudomotor function, contribute to clinical presentation of CRPS and affect autonomic function at all stages of CRPS.

Local Sympathetic Denervation in Painful Diabetic Neuropathy

“…The findings that the plasma NE level is higher in painful than in painless diabetic neuropathy (7) and that ␣ 1 -adrenergic antagonists may be effective in some patients with neuropathic pain (8) lend further support to this idea. The quality of the pain resembles that in patients suffering from complex regional pain syndrome (CRPS), formerly called reflex sympathetic dystrophy (RSD) (9,10).…”

Assessment of heart rate variability in the patients suffering with chronic pain of musculoskeletal origin

“…Since then a lot of work has been done in identifying correlations between HRV and chronic pain. [18,[22][23][24] Studies indicate that the involvement of the ANS at both the systemic and local levels is an important element of the pathogenesis of chronic musculoskeletal pain. It is also hypothesized that the treatment of chronic musculoskeletal disorders will improve the ANS balance which in turn will improve the cardiovascular functions.…”

Assessment of cardiac sympathovagal activity in the patients suffering from ankylosing spondylitis

“…The autonomic nervous system governs the cardiovascular system and this fact has resulted to various studies showing relations between autonomic dysfunction and chronic pain. [9,10] Since any alterations in the autonomic nervous system bring about the changes in the cardiovascular parameters such as BP and HR, therefore, VM and TTT were performed in this study to evaluate the autonomic reactivity. The increase in HR during exercise is due to the activation of the sympathetic nervous system with simultaneous suppression of the parasympathetic nervous system.…”

“…The autonomic nervous system governs the cardiovascular system and this principle has led to various studies showing relations between autonomic dysfunctions and chronic pain. [9,10] Since any alterations in the autonomic nervous system bring about the changes in the cardiovascular parameters such as blood pressure (BP) and HR, therefore, Valsalva maneuver (VM) and tilt-table test (TTT) were performed to evaluate the cardiac sympathovagal activities in the patients suffering from the AS.…”