autonomic neuropathy in which the sympathetic nerve function has been divided into two distinct regions

autonomic neuropathy in which the sympathetic nerve function has been divided into two distinct regions

CS or compensatory hyperhidrosis is the most common and troublesome side-effect of hyperhidrosis surgery and is the leading cause of patient regret after sympathetic surgery.
A severe form of CS is the split-body syndrome, corposcindosis, which is defined as an
autonomic neuropathy in which the sympathetic nerve function has been divided into two distinct
regions, one dead and the other hyperactive. In these cases, the patient feels like he or she is living
in two separate bodies.
The rates of CS in some series from the past 10 years are summarized in Table 4, with rates of mild CS varying from 14% to 90% and severe CS from 1.2% to 30.9%.
Some investigators only report on patients who have severe CS because they believe that almost all patients develop mild CS after sympathectomy.
Pascal DUMONT Thorac Surg Clin 18 (2008) 193–207

produces the equivalent of a sympathectomy, preventing noradrenaline release

Bretylium
Class III
Mode of action
- increases action potential duration and refractory period of cardiac cells
- antifibrillatory effect on ventricular muscle - may be more important than class III effects in emergency treatment of malignant ventricular arrhythmias
- initially causes noradrenaline release and then produces the equivalent of a
sympathectomy, preventing noradrenaline release (class II effect)
Clinical use
- useful adjunct to DC shock in managing life-threatening ventricular
arrhythmias, especially refractory VF
- theoretical advantages of lignocaine but no advantage has been demonstrated clinically

alterations in the relative abundance of TH mRNA mediate changes in TH activity induced by chronic stress or sympathectomy

These results indicate that alterations in the relative abundance of TH mRNA mediate changes in TH activity induced by chronic stress or sympathectomy, and that these changes require an intact sympathetic input.

Journal of Neuroscience Research

Volume 16 Issue 1, Pages 13 - 24

Published Online: 11 Oct 2004

Cardiac hypertrophy accelerated by left cervical sympathectomy

Cardiac hypertrophy in spontaneously hypertensive rats was accelerated by denervation of the left cervical sympathetic ganglia. Supersensitivity due to denervation may also exist in cardiac muscles.

	Biomedical and Life Sciences
SpringerLink Date	Tuesday, August 02, 2005

The HPA axis regulates the secretion of glucocorticoids (GCs), which play important roles in diverse brain functions, including cognition, emotion

Several neurological diseases are frequently accompanied by dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis regulates the secretion of glucocorticoids (GCs), which play important roles in diverse brain functions, including cognition, emotion, and feeding. Under physiological conditions, GCs are adaptive and beneficial; however, prolonged elevations in GC levels may contribute to neurodegeneration and brain dysfunction. In the current study, we demonstrate that apolipoprotein E (apoE) deficiency results in age-dependent dysregulation of the HPA axis through a mechanism affecting primarily the adrenal gland.
The Journal of Neuroscience, March 1, 2000, 20(5):2064-2071

peripheral sympathetic denervation may modulate immune function via activation of the hypothalamic-pituitary-adrenal (HPA) axis

Together, these findings suggest that peripheral sympathetic denervation may modulate immune function via activation of the hypothalamic-pituitary-adrenal (HPA) axis.

Ann N Y Acad Sci. 2000;917:923-34.

Increasing evidence suggests that the detrimental effects of glucocorticoid (GC) hypersecretion occur by activation of the hypothalamic-pituitary-adrenal (HPA) axis in several human pathologies, including obesity, Alzheimer's disease, AIDS dementia, and depression. The different patterns of response by the HPA axis during chronic activation are an important consideration in selecting an animal model to assess HPA axis function in a particular disorder.

Detrimental effects of chronic hypothalamic-pituitary-adrenal axis activation. From obesity to memory deficits
Raber J Mol Neurobiol 1998 Aug; 18(1): 1-22

Renin-Angiotensin activation following sympathectomy

"After sympathectomy, BP is maintained at nearly normal levels mainly through activation of the renin angiotensin system. (Heart and Circulatory Physiology, Vol 259, Issue 5 1337-H1342, Copyright © 1990 by American Physiological Society).

We should note that baroreflex response for maintaining cardiovascular stability is
suppressed in the patients who received the ETS.
Anesthesiology 2001; 95:A160

“cervical sympathectomy isolates all these sympathetic ganglion cells from the central nervous system and prevents them from responding to reflex or emotional changes in the central nervous system." Cunningham's Manual of Practical Anatomy: Volume III: Head, Neck and Brain, 1986

The renin-angiotensin system (RAS) is a major regulatory system of cardiovascular and renal function. Many new aspects of this system have been revealed in recent years, leading to new therapeutic approaches. It's well known that RAS blocking agents have potent antiatherosclerotic effects, which are mediated by their antihypertensive, anti-inflammatory, antiproliferative, and oxidative stress lowering properties. Inhibitors of RAS are now first-line treatments for hypertensive target organ damage. Their effects are greater than expected by their ability to lower blood pressure. Angiotensin receptor blockers reduce the frequency of atrial fibrillation and stroke, are also able to prevent cardiovascular and renal events in diabetic patients. Thus, blockade of RAS represents one of the most important strategies in order to reduce cardiovascular risk.

Neurol Sci. 2008 Sep;29 Suppl 2:S277-8.

Renin-angiotensin system and stroke.

Marcheselli S, Micieli G.

Patients may develop bradycardia after surgical procedure

Upper-Thoracic Sympathectomy; Patients may develop bradycardia after surgical procedure
Heart Disease Weekly. Atlanta: Feb 23, 2003. pg. 71

sympathectomy-induced increases in choroidal thickness, vascular luminal area and large venules and large arterioles

Sympathetic denervation for 6 weeks resulted in increased choroidal thickness, vascular luminal area, numbers of large venules and large arterioles, and capillaries in the outer nuclear layer. Capsaicin pretreatment prevented sympathectomy-induced increases in choroidal thickness, vascular luminal area and large venules and large arterioles, whereas pterygopalatine ganglionectomy was without effect."
Biotech Week. Atlanta: Jan 21, 2004. pg. 396

83% of patients reported severe 'compensatory sweating'

Fully 83% of patients who underwent T2 sympathectomy reported severe compensatory sweating one year after surgery and the majority of those reported they regretted the decision to have the surgery.
Heather Ennis. Medical Post. Toronto: Feb 15, 2005. Vol. 41, Iss. 7; pg. 17, 2 pgs

sympathectomy increased the bacterial tissue burden

sympathectomy increased the bacterial tissue burden, which was caused by a reduction in corticosterone tonus, and decreased both interleukin-4 secretion from peritoneal cells and the influx of lymphocytes into the peritoneal cavity. In both models, the peritoneal wall was the critical border for systemic infection. These results show the dual role of the sympathetic nervous system in sepsis. It can be favorable or unfavorable, depending on the innate immune effector mechanisms necessary to overcome infection.
The Journal of Infectious Diseases. Chicago: Aug 15, 2005. Vol. 192, Iss. 4; pg. 560, 13 pgs

pineal gland and extracerebral blood vessels folowing sympathectomy

Following removal of the superior cervical ganglion (SCG), large molecular weight (MW) NGF species, including proNGF-A, were increased in distal intracranial SCG targets, such as pineal gland and extracerebral blood vessels (bv).

Brain Research; Research from Miami University provides new data about brain research

Science Letter. Atlanta: May 15, 2007. pg. 1746

Neuronal Source of Plasma Dopamine

Determinants of plasma norepinephrine (NE) and epinephrine concentrations are well known; those of the third endogenous catecholamine, dopamine (DA), remain poorly understood. We tested in humans whether DA enters the plasma after corelease with NE during exocytosis from sympathetic noradrenergic nerves. We reviewed plasma catecholamine data from patients referred for autonomic testing and control subjects under the following experimental conditions: during supine rest and in response to orthostasis; intravenous yohimbine (YOH), isoproterenol (ISO), or glucagon (GLU), which augment exocytotic release of NE from sympathetic nerves; intravenous trimethaphan (TRI) or pentolinium (PEN), which decrease exocytotic NE release; or intravenous tyramine (TYR), which releases NE by nonexocytotic means. We included groups of patients with pure autonomic failure (PAF), bilateral thoracic sympathectomies (SNS-x), or multiple system atrophy (MSA), since PAF and SNS-x are associated with noradrenergic denervation and MSA is not. Orthostasis, YOH, ISO, and TYR increased and TRI/PEN decreased plasma DA concentrations. Individual values for changes in plasma DA concentrations correlated positively with changes in NE in response to orthostasis (r = 0.72, P < 0.0001), YOH (r = 0.75, P < 0.0001), ISO (r = 0.71, P < 0.0001), GLU (r = 0.47, P = 0.01), and TYR (r = 0.67, P < 0.0001). PAF and SNS-x patients had low plasma DA concentrations. We estimated that DA constitutes 2%-4% of the catecholamine released by exocytosis from sympathetic nerves and that 50%-90% of plasma DA has a sympathoneural source. Plasma DA is derived substantially from sympathetic noradrenergic nerves.
David S Goldstein, Courtney Holmes. Clinical Chemistry. Washington: Nov 2008. Vol. 54, Iss. 11; pg. 1864, 8 pgs

sympathectomy decreased cardiac sympathetic nerve density and norepinephrine level

Cardiac sympathetic innervation was visualized by means of a glyoxylic catecholaminergic histofluorescence method. Transient outward current (I-to) of ventricular myocytes was recorded with the whole-cell configuration of the patch clamp technique. We observed that sympathectomy (i) decreased cardiac sympathetic nerve density and norepinephrine level, (ii) reduced the protein expression of Kv4.2, Kv1.4, and Kv channel-interacting protein 2 (KChIP2), (iii) decreased current densities and delayed activation of I-to channels, (iv) reduced the phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and cAMP response element-binding protein (CREB), and (v) increased the severity of ventricular fibrillation induced by rapid pacing.
Heart Disease Weekly. Atlanta: Dec 28, 2008. pg. 54

Pain following endoscopic sympathectomy

The mean postoperative follow-up period was 11.5 months (range, 3-25 months). The hands of all patients were warm and dry after operation. No conversion to open surgery was necessary, and no operative mortality was recorded in either group. The mean inpatient pain scores were significantly higher in the biportal group (1.2 +/- 0.6) than that in the uniportal group (0.89 +/- 0.5, P=0.025). For the first three weeks after operation, four out of 20 (20%) patients in the uniportal group constantly suffered from mild or moderate residual pain while eight out of 25 (32%) cases in the biportal group (P=0.366). Among them, two cases in the uniportal group and five cases in the biportal group need to take analgesics.
Medical Devices & Surgical Technology Week. Atlanta: Sep 6, 2009. pg. 203

Laparoscopic surgery is associated with an increased incidence of postoperative atelectasis

Atelectasis occurs regularly after induction of general anesthesia, persists postoperatively, and may contribute to significant postoperative morbidity and additional health care costs. Laparoscopic surgery has been reported to be associated with an increased incidence of postoperative atelectasis.
Anesth Analg 2009; 109:1511-1516
© 2009 International Anesthesia Research Society

significant adverse effects on cardiopulmonary physiology

Because of technologic advances and improved postoperative recovery, endoscopic surgery has become the technique of choice for many thoracic surgical procedures^{6 and 25}; however, endoscopic visualization of intrathoracic structures requires retraction or collapse of the ipsilateral lung, which can have significant adverse effects on cardiopulmonary physiology. These cardiopulmonary changes can be further affected by the pathophysiologic changes associated with the disease process requiring the surgical procedure.

Because acute changes in cardiopulmonary function can compromise patient safety severely, a clear understanding of the dynamic interaction between the anesthetic–surgical technique and patient physiology is essential. This article discusses the effect of thoracoscopic surgery and the impact of various anesthetic interventions on cardiovascular and pulmonary physiology. In addition, some recommendations for “damage control” are made.

Anesthesiology Clinics of North America
Volume 19, Issue 1, 1 March 2001, Pages 141-152

Surgical Upper Thoracic Sympathectomy Reduces Arterial Oxygenation During One-Lung Ventilation

References and further reading may be available for this article. To view references and further reading you must purchase this article.

Journal of Cardiothoracic and Vascular Anesthesia
Volume 19, Issue 5, October 2005, Pages 703-704

PATHOPHYSIOLOGY OF ONE-LUNG VENTILATION

In estimating the degree of shunt that is created by one-lung ventilation when it is performed in the lateral decubitus position, on average, 40% of cardiac output perfuses the nondependent lung and the remaining 60% perfuses the dependent lung (Fig. 1).¹⁵ Mechanisms that tend to decrease the percent of cardiac output perfusing the nondependent, nonventilated lung are passive (e.g., mechanical-like gravity, surgical manipulation, amount of pre-existing lung disease) or active (e.g., hypoxic pulmonary vasoconstriction).¹⁵ The normal response of the pulmonary vasculature to atelectasis is an increase in pulmonary vascular resistance (in the atelectatic lung), and the increase in atelectatic lung resistance is almost entirely caused by hypoxic pulmonary vasoconstriction. Hypoxic pulmonary vasoconstriction is a protective reflex mechanism that diverts blood flow away from the atelectatic lung. With an intact hypoxic pulmonary vasoconstriction response, the transpulmonary shunt through the nondependent lung decreases to approximately 23% of the cardiac output (see Fig. 1).
Anesthesiology Clinics of North America
Volume 19, Issue 3, 1 September 2001, Pages 435-453

sympathectomy will blunt the normal tachycardic response to hypovolemia.

Spinal or epidural analgesia may cause a sympathectomy that will blunt the normal tachycardic response to hypovolemia.
OBSTETRIC ANAESTHESIA OUR WAY
Royal Women's Hospital Melbourne
Author: Dr Philip Popham

Influence of thoracic sympathectomy on cardiac induced oscillations in tissue blood volume

The parameter AM/BL is proportional to the cardiac-induced blood volume increase, which depends on the arterial wall compliance. AM/BL increased after the thoracic sympathectomy treatment (for male patients, from 2.60 ± 1.49% to 4.81 ± 1.21%), as sympathetic denervation decreases arterial tonus in skin. The very low-frequency (VLF) fluctuations of BL or AM showed high correlation (0.90 ± 0.11 and 0.92 ± 0.07, respectively) between the right and left hands before the thoracic sympathectomy, and a significant decrease in the right-left correlation coefficient (to 0.54 ± 0.22 and 0.76 ± 0.20, respectively) after the operation. The standard deviation of the BL or AM VLF fluctuations also reduced after the treatment, indicating sympathetic mediation of the VLF PPG fluctuations. The study also shows that the analysis of the PPG signal and the VLF fluctuations of the PPG parameters enable the assessment of the change in sympathetic nervous system activity after thoracic sympathectomy.
http://cat.inist.fr/?aModele=afficheN&cpsidt=14106877

low heart rate variability is associated with an increased risk for sudden cardiac death

The amount of short- and long-term variability in heart rate reflects the vagal and sympathetic function of the autonomic nervous system, respectively. Therefore heart rate variability can be used as a monitoring tool in clinical conditions with altered autonomic nervous system function. In postinfarction and diabetic patients, low heart rate variability is associated with an increased risk for sudden cardiac death. A sympathovagal imbalance is also detectable with heart rate variability analysis in coronary artery disease and essential hypertension.
http://www.annals.org/content/118/6/436.abstract

Thursday, November 12, 2009

Isointegral mapping revealed that ETS altered electroactivity on the heart

In the head-up tilt study, R–R intervals significantly increased after the surgery in the head-up tilt positions (P<0.05),> difference in the supine position. There is no significant difference in QTc and Twa before and after the surgery, both in the supine and the head-up tilt positions. There was no significant difference in the LF or HF before and after surgery, either in the supine position or the head-up tilt positions. In the LF/HF, there was no significant difference before and after surgery in the supine position. However, the LF/HF in the head-up tilt positions was significantly decreased after surgery (P<0.05).> suppression of ETS was recognized more obviously under the steeper head-up tilt positions. Conclusions: The influences on the cardiac autonomic nerve system of the ETS of upper thoracic sympathetic nerve were seen to be of a lesser degree at rest. However, the response to sympathetic stimulation was suppressed after the surgery.
Eur J Cardiothorac Surg 1999;15:194-198

Obviously, it is not simply a compensatory hyperhidrosis transposition

Obviously, it is not simply a compensatory hyperhidrosis transposition from postoperative reduction of palmar sweating. Based on our observations, we postulated two possible mechanisms. The first of these mechanisms is denervation hypersensitivity of the surgically injured distal sympathetic stump. This could explain why CH may appear soon after sympathectomy, but is not found in patients who undergo local excision of axillary sweat glands or undergo local treatment. Another mechanism is regeneration of preganglionic fibers or collateral sprouting of sympathetic fibers from the proximal stump of the sympathetic trunk. This could explain the long-term existence of PCH.

Ann Thorac Surg 2001;72:667-668

collateral effects of thoracic sympathectomy not disclosed to patients

Several reports also demonstrate significantly lower heart rate increases during exercise in subjects who have undergone bilateral ISS [9–12] compared to pre-surgical levels. In spite of this high occurrence, recent reviews on the usual collateral effects of thoracic sympathectomy still do not include these possible cardiac consequences [6].
Eur J Cardiothorac Surg 2001;20:1095-1100

similar to beta-blocker therapy

Findings on ¹²³I-MIBG imaging studies indicate that EUTS (endoscopic upper thoracic sympathectomy) suppresses the activation of the sympathetic nervous system slightly, similar to beta-blocker therapy.
JNS - March 2004 Volume 100, Number 3

Introduction Essential hyperhidrosis (EH) is often considered to be related to an increased activity of sympathetic nervous system (SNS). However, there is a lack of studies comparing autonomic nervous system (ANS) activity in controls and in EH patients. The aim of the present study was to simultaneously investigate in patients with severe EH, blood pressure, heart rate variability and plasma catecholamine levels in comparison with controls.

Methods 19 EH patients and 20 controls with normal ANS function assessed by clinical testing were included. Blood pressure (BP) and heart rate (HR) were measured using a Finapres beat-to-beat monitor. BP and HR variabilities (Fast Fourier transformation) and plasma catecholamine levels (HPLC) were obtained at rest and during a 15 min 70° head-up tilt test.

Results At rest, a significantly higher relative energy of low frequency band (LF) of systolic BP was observed in EH in comparison with controls contrasting with the lack of difference in BP, HR, plasma catecholamine levels and in other spectral parameters. During tilt, all changes were comparable in EH and in control subjects excepting relative energy of LF of SBP which remained unchanged when compared to the resting condition in EH group.

Conclusions In EH, SNS is not overreactive even if resting overactivity cannot be excluded.
http://www.springerlink.com/content/xe7g2w72617phl0e/
Volume 13, Number 4 / August, 2003

Posted by Mia at 3:55 PM

Clinical conditions that cervico-thoracic sympathetic blockade may benefit

...Miscellaneous conditions in head region: stroke, Meniere disease, tinnitus
Amblyopia due to quinine poisining (also causes retinal artery spasm and thrombosis)

Cousins and Bridenbaugh's Neural Blockade in Clinical Anesthesia and Pain Medicine by Michael J Cousins, Phillip O Bridenbaugh, Daniel B Carr, and Terese T Horlocker

Wolters Kluwer Health
Edition: 4 - 2008

Acquired cardiovascular disease following Sympathectomy

Effects of endoscopic thoracic sympathectomy for primary hyperhidrosis on cardiac autonomic nervous activity

We found statistically significant differences (P < .05) in both time and frequency domains. Parameters that evaluate global cardiac autonomic activity (total power, SD of normal R-R intervals, SD of average normal R-R intervals) and vagal activity (rhythm corresponding to percentage of normal R-R intervals with cycle greater than 50 ms relative to previous interval, square root of mean squared differences of successive normal R-R intervals, high-frequency power, high-frequency power in normalized units) were statistically significantly increased after sympathectomy. Low-frequency power in normalized units, reflecting sympathetic activity, was statistically significantly decreased after sympathectomy. Low-/high-frequency power ratio also showed a significant decrease, indicating relative decrease in sympathetic activity and increase in vagal activity.

The Journal of Thoracic and Cardiovascular Surgery
Volume 137, Issue 3, March 2009, Pages 664-669

sympathectomy leads to peripheral vasodilation, reduced preload, and subsequently decreased cardiac output

Despite a duration of only 2 week, repeated IVRS (intravenous regional sympathetic block) efferent blocks are an attractive alternative to the higher-risk techniques of thoracic sympathetic block and thoracic surgical or thoracoscopic sympathectomy. (p. 848)

Table 42-1
Classification of percutaneous neural destructive procedures:
Anatomy
1. Peripheral neurotomy (such as destruction of intercostal, ilioinguinal nerves)
2. Rhizotomy (spinal dorsal root rhizotomy, trigeminal rhizotomy)
3. Destruction of sensory pathways in the spinal cord (midline punctuate myelotomy, cordotomy)
4. destruction of brain sensory centers (hypophysectomy)
5. Sympathectomy
(p.992)

The authors found that the incidence of hypotension was a function of the level of sympathetic denervation, occurring in 60% of patients with a T7 sympathectomy, and in 100% of patient with a T4 or higher level of sympathectomy.
(p 226)

After thoracoscopic sympathectomy for hyperhidrosis, very severe discomfort and hyperhidrosis in the neighboring non-sympathectomized regions occurred with alarming frequency and intensity.
(p.879)

Cardiovascular effects of epidural blockade
"Central" Sympathetic block (T1-T4) - Blockade of
Cardiac sympathetic outflow from vasomotor center
Cardiac sympathetic reflexes at segmental level
Vasoconstrictor fibers to head, neck, and arms

Effect:
HR ↓ CO ↓
Vasodilation in upper limbs
"Inappropriate bradycardia"; "sudden bradycardia"; vagal arrest (p. 247)

↓↓Venous return may result in sudden parasympathetic tone ("faint response")
↓ ↓ HR → cardiac arrest

"Inappropriate" bradycardia (i.e. "normal" HR in face of ↓MAP with sensory level T3-T4)
Peripheral vasodilation should evoke an ↑ HR. But ↓ venous return → ↑vagal tone, so HR remains at preblock rate but is "inappropriately" slow.

↓HR with visceral traction in presence of blockade to T1.
Total sympathetic block
Unopposed vagus
Changes in vagal tone → profound changes in HR; may → transient asystole (p. 248)

Thermoregulation and Shivering
Hypothermia (a decrease in core temperature) is common in patients undergoing surgery with epidural anesthesia and is thought to result from heat loss to the cold environment due to sympathectomy-induced vasodilation. The normal process by which thermoregulation usually minimizes intraoperative core temperature is prevented, since epidural anesthesia directly inhibits vasoconstriction in the analgesic dermatomes. (p.253)

Central neuraxial anesthesia-induced sympathectomy leads to peripheral vasodilation, reduced preload, and subsequently decreased cardiac output. The incidence and extent of hypotension depends on the height of the block, the patient's position, and whether appropriate measures were instituted prophylactically to minimize hypotension.

Cousins and Bridenbaugh's Neural Blockade in Clinical Anesthesia and Pain Medicine by Michael J Cousins, Phillip O Bridenbaugh, Daniel B Carr, and Terese T Horlocker

Wolters Kluwer Health
Edition: 4 - 2008

Perioperative risks are low, but complications can be devastating

Endoscopic thoracic sympathectomy (ETS) involves division of the thoracic sympathetic chain between T2 and T4.

The main indication for ETS is the treatment of palmar hyperhidrosis.

The most common method of anaesthesia for ETS uses intermittent positive pressure ventilation via a standard tracheal tube.

Perioperative risks are low, but complications can be devastating.

Postoperative compensatory sweating occurs in almost 50% of patients.

• Oxford Journals
• Medicine
• BJA: CEACCP
• Volume 9, Number 2
• Pp. 52-55

hypoxic pulmonary vasoconstriction may be impaired after Sympathectomy

It is well known that hypoxic pulmonary vasoconstriction(HPV) plays an important role to protect hypoxemia during the atelectasis induced by one-lung ventilation. Thoracic sympathectomy may have effects on pulmonary vasculature(HPV) and hemodynamics during one-lung anesthesia.

Mean arterial blood pressure was decreased from 81.9+/-2.89 to 73.2+/-2.49 mmHg after thoracic sympathectomy and heart rate was decreased from 104.4+/-3.12 to 88.2+/-2.31beats/min. Arterial oxygen tension was decressed from 570.5+/-17.9 to 521.4+/-23.2mmHg after position change, and decreased to 271.1+/-28.1 mmHg under one-lung ventilation, and finally decreased to 217.0+/-18.3 mmHg after thoracic sympathectomy. With the above results, we can conclude that patients for TES should be carefully observed during and after the procedure, and hypoxic pulmonary vasoconstriction may be impaired after TES.
Korean J Anesthesiol. 1993 Aug;26(4):695-699.

profound decrease of arterial oxygen partial pressure during sympathectomy

Left-lung ventilation and right-chest operation caused profound decrease of arterial oxygen partial pressure (PaO2), compared with two-lung ventilation before surgery (70.7%, P > 0.0003) and compared with PaO2 at two-lung ventilation during and after surgery (decrease of 80.1% and 75.3%, respectively; P > 0.001 and < 0.005, respectively). Right-lung ventilation and left-chest operation did not cause hypoxemia.

Pulse oximetry and repeated blood gas measurements are needed during endoscopic transthoracic sympathectomy in order to detect and treat hypoxemic events, which may jeopardize the patient's life.
Journal of Cardiothoracic and Vascular Anesthesia
Volume 10, Issue 2, February 1996, Pages 207-209

Spinal cord infarction occurring during thoraco-lumbar sympathectomy

Spinal cord infarction, because of interference with an important radicular tributary, is a rare complication of thoraco-lumbar sympathectomy.
In a brief survey of the literature we found only 12 previously recorded cases in which this complication
was presumed to have occurred.
J. Neurol. Neurosurg. Psychiat., 1963, 26, 418