Endoscopic Thoracic Sympathectomy

Question 1

What are the indications for an endoscopic thoracic sympathectomy?

Answer 1

Palmar, Axillary or Craniofacial Hyperhydrosis(excessive sweating)
Chronic regional Pain syndromes of the upper limb
Facial Blushing
Chronic Angina Pectoris that is unmanageable by pharmacological or cardiac intervention ( rare indication now)

Question 2

Describe the sympathetic nerve supply to the upper limb

Answer 2

Remember the basics of the autonomic nervous system, i.e., Preganglionic, Ganglion, Postganglionic

Preganglionic Sympathetic Fibres originate from the spinal nerves T1 - T4/5

Synapse in the superior middle cervical and inferior stellate cervical ganglia

Postganglionic fibres travel to effector cells

Question 3

What are the general implications of managing a patient for Endoscopic Thoracic Sympathectomy

Answer 3

Occasionally, conversion to open surgery from laparoscopy is required, so we need to prep and drape for a thoracotomy

There is a risk of major haemorrhage, so will require 2 large bore IV access as well as 2 group and save samples for rapid blood issue

Periods of hypoxia are common, for a variety of reasons including shunt due to one lung ventilation, atelectasis and failure to fully inflate the first lung before proceeding with surgery on the second side

Periods of Hypotension due to capnothorax (CO2 occupying space in the pleural cavity mimicking a pneumothorax) are likely, and hence invasive BP monitoring would be advised.

Question 4

State complications due to patient positioning that may occur during Endoscopic Thoracic Sympathectomy under GA

Answer 4

When in a supine or reverse Trendelenburg position, the arms are abducted, creating a risk for brachial plexus injury

In the prone position, there is a risk of:
facial or eye damage, dislodgement of the airway, brachial plexus injury

In the lateral Position, there is a risk of:
Difficulty with ventilation, dislodgement of the airway, damage to pressure points e.g. the common peroneal nerve

Question 5

What are the airway options for airway management for an Endoscopic Thoracic Sympathectomy under GA

Answer 5

One lung ventilation with a double-lumen tube
One lung ventilation with an ET tube and bronchial blocker
ET Tube with intrathoracic CO2 insufflation
LMA with intrathoracic CO2 insufflation

Question 6

What intraoperative complications may be encountered during an Endoscopic Thoracic Sympathectomy

Answer 6

Airway

Malposition of the Double Lumen Tube or Bronchial Blocker may cause hypoxia

Respiratory

One lung ventilation causes a shunt and hence hypoxia
(Of note, methods to improve oxygenation may actually worsen hypoxia, for example, O2 insufflation or CPAP to the deflated lung may reduce hypoxic pulmonary vasoconstriction; equally, increasing PEEP to the ventilated lung may increase resistance to blood flow on the ventilated side.)

With bilateral surgery, atelectasis of the reinflated lung may cause significant hypoxia when operating on the second side, hence, it is worth considering re-inflation under direct vision

Cardiovascular

Hypotension due to capnothorax (CO2 occupying space in the pleural cavity mimicking a pneumothorax)

Rarely cardiac arrest due to rapid insufflation

Cardiac Arrhythmia induced by intrathoracic diathermy

Rarely bleeding due to inadvertent damage to blood vessels on port insertion, which can be catastrophic

Question 7

What postoperative complcations can occur following a Endoscopic Thoracic Sympathectomy

Answer 7

Ongoing hypoxia due to residual pneumothorax / atelectasis

Risk of acute lung injury in the days following the operation especially if protective one lung ventilation was not used

Chest pain during the immediate post operative period requiring intravenous morphine and require an overnight stay

Compensatory Hyperhidrosis (excessive sweating)