sympathectomy affects the brain: April 2012

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

Wednesday, April 25, 2012

Sympathectomy increased the pain threshold and made the sympathectomized rats hypesthetic

Normal adult rats were sympathectomized at L2-L3. The threshold for thermal noxious pain by hot-plate analgesia test and changes in neuropeptides in the lumbar dura mater and dorsal root ganglia using light microscopic immunohistochemistry were assessed and compared with control rats.

Results: In the hot-plate analgesia test, sympathectomized rats increased their hot-plate latency time compared with that of sham-operated rats. Density of calcitonin gene-related peptide immunoreactive fibers in sympathectomy side of the lumbar dura mater decreased to 45.5% compared with the contralateral side. The number and size of calcitonin gene-related peptide immunoreactive cells in dorsal root ganglia showed no difference between sympathectomized and contralateral side.

Conclusion: Sympathectomy increased the pain threshold and made the sympathectomized rats hypesthetic. A large numbers of sensory fibers innervated the lumbar dura mater via L2-L3 sympathetic nerve in rats. Sympathectomy reduced the number of these nerve fibers in the lumbar dura mater. Sympathetic nerves may play an important role for low back pain involving the lumbar dura mater.

http://journals.lww.com/spinejournal/Abstract/1996/04150/An_Anatomic_Study_of_Neuropeptide.4.aspx

Long-term sympathectomy induces sensory and parasympathetic fibres sprouting, and mast cell activation in the rat dura mater

http://discovery.ucl.ac.uk/1330488/

There are similarities between the delayed onset of the human pain state and the delayed rise in sensory peptides after sympathectomy

The effect of sympathectomy on the calcitonin gene-related peptide (CGRP) level in the rat primary trigeminal sensory neurone was investigated. Six weeks after bilateral removal of the superior cervical ganglion there was a 70% rise in the CGRP content of the iris and the pial arteries, a 34% rise in the concentration in the trigeminal ganglion but no change in the brainstem. The CGRP rise in both end organs suggests that this phenomenon may be common to all peripheral organs receiving combined sensory and sympathetic innervations. The lack of any rise in the brainstem CGRP content raises the possibility that this process spares central terminations. In contrast, the level of neuropeptide Y, a peptide mainly contained in sympathetic terminals, fell to 35% of control values in the iris and pial arteries whilst the trigeminal ganglion and brainstem concentrations remained unchanged. The possible relevance of these observations to the clinical syndrome of postsympathectomy pain (sympathalgia) is discussed. There are similarities between the delayed onset of the human pain state and the delayed rise in sensory peptides after sympathectomy.
http://www.ncbi.nlm.nih.gov/pubmed/3877546

sympathectomy resulted in complete disappearance of histochemically detected adrenergic and a considerable decrease of cholinergic nerve fibers in the pial arterial walls

sympathectomy resulted in complete disappearance of histochemically detected adrenergic and a considerable decrease of cholinergic nerve fibers in the pial arterial walls. The vasodilatation was much less obvious in sympathectomized than in control animals. This was associated with (and probably caused by) a considerable rise in histochemically detected serotonin activity of the pial arteries walls. After recovery of blood supply to the brain the constriction of the pial arterial active segments restricting the excessive cerebral blood flow, was significantly reduced due, probably, to the sympathetic deprivation. Therefore, the sympathetic control plays an important part in pial arterial responses regulating the adequate blood supply of the cerebral cortex.
http://www.ncbi.nlm.nih.gov/pubmed/7173422

Monday, April 23, 2012

Digital infrared thermal image after T2 sympathicotomy or T3 ramicotomy.

(A) Clear cut change of skin temperature after a T2 sympathicotomy. (B) An even distribution of skin temperature after ramicotomy.

Gossot and colleagues [8] analyzed a group of T2, T3, T4 sympathectomypatients in comparison with a group of patients undergoing aT2, T3, T4 ramicotomy and they reported no statistical differenceregarding the incidence of CS between the two groups studied(72.2% and 70.9%). However in terms of the severity of CS (embarrassing,disabling) causing inconveniences to daily life, they reported27% and 13% incidences in these two groups, respectively. Thesefindings suggest that by preserving the sympathetic trunk, itwas possible to reduce the severity of CS.

The preganglionic fibers of the sympathetic nerve to the armoriginate mostly from the spinal segments T3–T6 and thepostganglionic fibers of the sympathetic nerve to the arm originatefrom T2 and, to a lesser extent, the T3 ganglia [9]. This impliesthat the division of preganglionic fibers (rami communicantes)reduces the extent of denervation of the sympathetic nerve ascompared with the division of postganglionic fibers (sympathetictrunk) in the treatment of palmar hyperhidrosis.
Sympathectomy or sympathicotomy is one of the procedures usedto divide the sympathetic trunk. Sympathicotomy distinctivelychanges sympathetic nerve distribution in comparison with aramicotomy. Figure 4A illustrates the clear-cut changes ofskin temperature after a T2 sympathicotomy. However the overallsympathetic nerve distribution to the body is not markedly changedafter a T3 ramicotomy because a T3 ramicotomy is a procedurethat is used to divide one of the preganglionic fibers and topreserve the sympathetic trunk. Figure 4B illustrates an evendistribution of skin temperature after T3 ramicotomy.

http://ats.ctsnetjournals.org/cgi/content/full/78/3/1052#FIG4

Tuesday, April 10, 2012

most surgeons do not have a clear understanding of their short-term outcomes for the majority of procedures they perform

The public would probably be surprised to know that most surgeons do not have a clear understanding of their short-term outcomes for the majority of procedures they perform.

Of even greater concern is the lack of data on long-term outcomes associated with surgical interventions.

Many surgeons argue that they are too busy and do not have the time and resources to conduct this sort of follow-up. This is not entirely without foundation, but it does seem difficult to defend a stance that says “I will continue to work feverishly at the operations I do but not assess how successful my results are”.

Guy Maddern (ASERNIP-s): No excuse for poor surgical outcomes

MJA INSIGHT, 8 August 2011

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autonomic vulnerability or visceral dysfunction may precipitate or aggravate mental symptoms

dynamic cerebral autoregulation is altered by ganglion blockade

After ganglion blockade, systolic and pulse pressure decreased significantly by 13% and 26%, respectively. CBF velocity decreased by 6% (P <0.05). In the very low frequency range (0.02 to 0.07 Hz), mean blood pressure variability decreased significantly (by 82%), while CBF velocity variability persisted. Thus, transfer function gain increased by 81%. In addition, the phase lead of CBF velocity to arterial pressure diminished. These changes in transfer function gain and phase persisted despite restoration of arterial pressure by infusion of phenylephrine and normalization of mean blood pressure variability by oscillatory lower body negative pressure.

Conclusions-: These data suggest that dynamic cerebral autoregulation is altered by ganglion blockade. We speculate that autonomic neural control of the cerebral circulation is tonically active and likely plays a significant role in the regulation of beat-to-beat CBF in humans.

Circulation. 106(14):1814-1820, October 1, 2002.

second thoracic sympathetic ganglion was most commonly located (50%) in the second intercostal space

anatomic variations of the T2 nerve root

6 (9.1%) sides showed a single large ganglion formed by the stellate and the second thoracic sympathetic ganglia. The second thoracic sympathetic ganglion was most commonly located (50%) in the second intercostal space. Conclusion: The anatomic variations of the intrathoracic nerve of Kuntz and the second thoracic sympathetic ganglion were characterized in human cadavers. Journal of thoracic and cardiovascular surgery Y. 2002, vol. 123, No. 3, pages 498-501 [bibl. : 14 ref. http://www.refdoc.fr/Detailnotice?idarticle=9466218

decreased conditioning-related activity in insula and amygdala after autonomic denervation

The degree to which perceptual awareness of threat stimuli and bodily states of arousal modulates neural activity associated with fear conditioning is unknown. We used functional magnetic neuroimaging (fMRI) to study healthy subjects and patients with peripheral autonomic denervation to examine how the expression of conditioning-related activity is modulated by stimulus awareness and autonomic arousal. In controls, enhanced amygdala activity was evident during conditioning to both "seen" (unmasked) and "unseen" (backward masked) stimuli, whereas insula activity was modulated by perceptual awareness of a threat stimulus. Absent peripheral autonomic arousal, in patients with autonomic denervation, was associated with decreased conditioning-related activity in insula and amygdala. The findings indicate that the expression of conditioning-related neural activity is modulated by both awareness and representations of bodily states of autonomic arousal.

http://www.ncbi.nlm.nih.gov/pubmed/11856537

Segmental myoclonus was associated with thoracic sympathectomy

Spinal myoclonus was associated with laminectomy, remote effect of cancer, spinal cord injury, post-operative pseudomeningocele, laparotomy, thoracic sympathectomy, poliomyelitis, herpes myelitis, lumbosacral radiculopathy, spinal extradural block, and myelopathy due to demyelination, electrical injury, acquired immunodeficiency syndrome, and cervical spondylosis.

http://www.ncbi.nlm.nih.gov/pubmed/3753263

Spinal myoclonus is typically associated with a localized area of damaged tissue (focal lesion). The injured area may include direct damage of the spinal cord or may cause abnormal changes in the function of the spinal cord.

http://www.wemove.org/myo/myo_pc.html

Spinal myoclonus following a peripheral nerve injury: a case report

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2526081/

decrease in CBF induced by sympathectomy cannot be attributed to hypersensitivity

Thus the decrease in CBF induced by chronic sympathectomy cannot be attributed to the development of hypersensitivity to catecholamines. This decrease remained stable whatever the value of resting flow and was maintained under anesthesia. It is concluded that, as in the peripheral circulation, chronic sympathectomy affects the equilibrium of the vascular smooth muscle fibers, but that circulating amines play no compensatory role in the cerebral circulation because of the blood-brain barrier.

http://www.sciencedirect.com/science/article/pii/0006899385902434

After the sympathectomy, the high night time excretion of melatonin was abolished

The amount of 6-sulphatoxymelatonin, the chief metabolite of melatonin, in the urine was measured in nine patients, who were subjected to bilateral sympathectomy at the second thoracic ganglionic level for treatment of hyperhidrosis of the palms. All patients showed before surgery a normal 6-sulphatoxymelatonin excretion with a peak in the excretion during the night time. After the sympathectomy, the high night time excretion was clearly abolished in five patients but remained high in four patients...
http://www.ncbi.nlm.nih.gov/pubmed/16647807

LIMITED SYMPATHECTOMY DOES NOT REDUCE SEVERITY OF SIDE-EFFECTS

On univariate and multivariate analysis, the extent of denervation was not associated with the occurrence or the severity of compensatory sweating.

Compensatory sweating and temporary relief/recurrence were equally considered to be the main causes of dissatisfaction. CONCLUSION: Compensatory sweating was the most common long-term complication of thoracodorsal sympathectomy for primary hyperhidrosis. Its incidence and severity were not associated with the extent of sympathectomy.

http://www.ncbi.nlm.nih.gov/pubmed/12514588

Muliptle organ failure as a consequence of elective sympathectomy

In the post-sympathectomy patient, the abnormalsympathetic skin response may lead to peripheral vascular failureor the reduced cardiac chronotropic response may impair thebody’s capacity to compensate for shock. These may havecontributed to the rapid development of shock and severe multipleorgan dysfunction syndrome in this patient.
He had multiple organ dysfunction syndrome develop, with severerenal and hepatic failure, grade II hepatic encephalopathy,and disseminated intravascular coagulation. He responded remarkablywell to aggressive supportive measures including forced alkalinediuresis, and he was eventually discharged home after 1 month. The patient was previously a healthy, physically fit, nonsmoker.He worked as a body building trainer and led an active, sportylifestyle. The only significant medical history was that hehad received thoracic sympathectomy for axillary hyperhidrosis4 years ago at another hospital.

http://ats.ctsnetjournals.org/cgi/content/full/84/3/1025

Cell body reorganization in the spinal cord after elective surgery to treat sweaty palms

slowing of the heart rate usually occurs on the second to fourth day after sympathectomy

The rate fell to a level between 40 and 6o per minute, the maximal slowing usually occurring on the second to fourth day after operation. Consistent slowing of the rate was not observed after a unilateral thoracic sympathectomy of either side. While there was some recovery from the maximum bradycardia with the passage of time in most patients, relatively slow resting cardiac rates and failure of tachycardia to develop with postural hypotension or exercise persisted in all patients.

Skoog's12 work has shown that there are marked differences in the number and precise location of the accessory ganglion cells in the cervical region in different patients and on the two sides in the same patient.
Annals of Surgery, 1949 October, Volume 130 Number 4

'Emotional' sweating regulated by neocortex and limbic cortex

Careful observations showed that the forearm sweating responded diversely to various mental stimuli, unlike the palmar sweating whose response was always an increase. Mental arithmetic, mental testing and physical exercise caused an immediate increase in the palmar sweating but often elicited a transient decrease in the forearm sweating, whereas pain, noise, and emotional stimuli consistently provoked an increase of sweating on the forearm as well as on the palm. These observations suggest that the activities of higher centers, presumably involving neocortex and limbic cortex, exert various influences on the central mechanisms of palmar and generalized sweating.
Jpn J Physiol. 1975;25(4):525-36.
http://www.ncbi.nlm.nih.gov/pubmed/1206808

The sympathetic nervous system is responsible for the physiological responses to emotional states

The common epithet of “fight or flight” is being enlarged to be “fight, flight, or fright” or even “fight, flight, fright, or freeze.” Cannon’s original contribution was a catchy phrase to express some of what the nervous system does in response to a threat, but it is incomplete. The sympathetic system is responsible for the physiological responses to emotional states. The name “sympathetic” can be said to mean that (sym- = “together”; -pathos = “pain,” “suffering,” or “emotion”). http://cnx.org/content/m46582/latest/?collection=col11496/latest