cell body reorganization in the spinal cord after sympathectomy

The amount of compensatory sweating depends on the patient, the damage that the white rami communicans incurs, and the amount of cell body reorganization in the spinal cord after surgery.
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf

After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.

http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract

Thursday, May 28, 2015

Middle cerebral artery blood velocity during exercise with beta-1 adrenergic and unilateral stellate ganglion blockade in humans

 2000 Sep;170(1):33-8.

Middle cerebral artery blood velocity during exercise with beta-1 adrenergic and unilateral stellate ganglion blockade in humans.

Abstract

A reduced ability to increase cardiac output (CO) during exercise limits blood flow by vasoconstriction even in active skeletal muscle. Such a flow limitation may also take place in the brain as an increase in the transcranial Doppler determined middle cerebral artery blood velocity (MCA V(mean)) is attenuated during cycling with beta-1 adrenergic blockade and in patients with heart insufficiency. We studied whether sympathetic blockade at the level of the neck (0.1% lidocaine; 8 mL; n=8) affects the attenuated exercise - MCA V(mean following cardio-selective beta-1 adrenergic blockade (0.15 mg kg(-1) metoprolol i.v.) during cycling. Cardiac output determined by indocyanine green dye dilution, heart rate (HR), mean arterial pressure (MAP) and MCA V(mean) were obtained during moderate intensity cycling before and after pharmacological intervention. During control cycling the right and left MCA V(mean) increased to the same extent (11.4 +/- 1.9 vs. 11.1 +/- 1.9 cm s(-1)). With the pharmacological intervention the exercise CO (10 +/- 1 vs. 12 +/- 1 L min(-1); n=5), HR (115 +/- 4 vs. 134 +/- 4 beats min(-1)) and delta MCA V(mean) (8.7 +/- 2.2 vs. 11.4 +/- 1.9 cm s(-1) were reduced, and MAP was increased (100 +/- 5 vs. 86 +/- 2 mmHg; P < 0.05). However, sympathetic blockade at the level of the neck eliminated the beta-1 blockade induced attenuation in delta MCA V(mean) (10.2 +/- 2.5 cm s(-1)). These results indicate that a reduced ability to increase CO during exercise limits blood flow to a vital organ like the brain and that this flow limitation is likely to be by way of the sympathetic nervous system.

Saturday, May 9, 2015

Sympathectomy at the level of the T2 ganglion leads to decreased negative feedback to the hypothalamus

Compensatory sweating was originally thought to be a mechanism of excessive sweating (in an anatomical region with an intact sympathetic nervous system) to maintain a constant rate of total sweat secretion.90 However, this theory was not confirmed by other studies, demonstrating that compensatory sweating represented a reflex action by an altered feedback mechanism at the level of the hypothalamus which is dependent on the level at which sympathetic denervation occurs. Sympathectomy at the level of the T2 ganglion leads to decreased negative feedback to the hypothalamus. When performing a sympathectomy at a lower level, the negative feedback to the hypothalamus is less inhibited, leading to a decrease in compensatory sweating. Chou et al.91 have proposed the term ‘reflex sweating’ to replace compensatory sweating. Other side effects described in a review article by Dumont89 are gustatory sweating, cardiac effects, phantom sweating, lung function changes, dry hands and altered taste. Besides these side effects there are significant risks of complications during and after surgery (arterial or venous vascular injury, pneumothorax, infection, Horner syndrome etc.).

JEADV 2012, 26, 1–8 Journal of the European Academy of Dermatology and Venereology