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.

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.

Spinal cord infarction occurring during thoraco-lumbar sympathectomy
J Neurol Neurosurg Psychiatry 1963;26:418-421 doi:10.1136/jnnp.26.5.418

Friday, July 15, 2011

Autonomic Neuropathy Differential Diagnoses

Aromatic L-amino acid decarboxylase deficiency 
Autonomic dysreflexia syndrome in spinal injuries. 
Dopamine beta-hydroxylase deficiency 
Multiple System Atrophy 
Parkinson Disease 
Parkinson-Plus Syndromes 
Progressive Supranuclear Palsy 
Pure Autonomic Failure 
Surgical sympathectomy 
Syphilis (tabes dorsalis) 

Tuesday, July 12, 2011

Skin depigmentation: could it be a complication caused by thoracic sympathectomy?

Patients need to be carefully counselled before committing to sympathectomy

However 43 patients (93%) suffered with compensatory sweating, of these 27 had to change clothes more than once daily. Compensatory sweating was graded as severe in 18 and incapacitating in 2. Of note only 5 patients noticed an improvement in the compensatory sweating over time. Only 26 (56%) would recommend thoracoscopic sympathectomy to others with hyperhydrosis.


Thoracoscopic sympathectomy is effective in the treatment of hyperhydrosis. However compensatory sweating seems unavoidable and infrequently improves with time. Patients need to be carefully counselled before committing to surgery.

Sunday, July 10, 2011

In a person who had a sympathectomy, the sympathetic component of the baroreceptor mechanism is absent

The baroreceptor reflex is only a short-term regulator of blood pressure because the receptors adapt by raising the threshold and lowering discharge rate.
8. Describe the reflex compensations when someone suddenly stands up from a supine position. What would happen in a patient who just had a sympathectomy?

Sudden standing causes pooling of blood in the leg veins. This results in decreased venous return to the heart, which leads to decreased cardiac output (Frank-Starling mechanism), which leads to decreased MAP. This decrease in MAP is detected by the carotid sinus baroreceptors, which relay a message to the medullary cardiovascular control center, which increases sympathetic outflow and decreases parasympathetic outflow, this causes:

* An increase in HR and myocardial contractility, tending to restore cardiac output.
* Vasoconstriction in skeletal musculature, skin, kidneys and gut, reducing blood flow to these organs and increasing TPR.
* Venoconstriction decreasing capacitance and increasing venous return

A patient with a sympathectomy would experience what's referred to as orthostatic hypotension (which might lead to syncope). Orthostatic hypotension is a decrease in arterial pressure when going from supine to a standing position. A person with a normal baroreceptor mechanism will try to restore MAP. In a person who had a sympathectomy, the sympathetic component of the baroreceptor mechanism is absent.

Heart Physiology II

M.A.S.T.E.R. Learning Program, UC Davis School of Medicine
Date Revised: Jan 16, 2002
Revised by: Gordon Li and Carolyn Nguyen