How I do it ... Thoracoscopic Sympathectomy

 

(or to be more exact, how Jim McGuigan does a thoracoscopic sympathectomy. I am grateful to my colleague Jim for allowing me to record his technique).

Rather than attempting to dissect the chain out for pathological examination we use cautery to divide the chain at multiple levels and to destroy the chain in between these divisions.

Indications
Palmar hyperhidrosis - the classic indication has been excessive palmar sweating. For some patients, especially young women, it is impossible to hold a pen, do paperwork, exams or other secretarial work. Electro-iontophoresis can be effective for some patients but many are not prepared to accept the inconvenience of this cumbersome treatment. It also tends to become less effective with time.

Raynaud's syndrome - reasonable improvement of symptoms and skin changes can be achieved by sympathectomy (extent similar to that for palmar hyperhidrosis). The improvement may, however, be only short-lived.


Axillary hyperhidrosis - sympathectomy also works well when Dri-Clor and other agents have ceased to be useful. Unlike BoTox which has to be injected subcutaneously every 6 weeks or so, sympathectomy produces a prolonged solution. Because of differences in distribution of sympathetic nerves and difficulties getting access to the 4th rib ganglion results for axillary sweating are less predictable than palmar. If significant boil formation, sepsis or cicatrisation are present in the axillae, excision by an experienced plastic surgeon may be required.


Facial blushing - patients undergoing sympathectomy for palmar hyperhidrosis have noticed that there has been a reduction in facial sweating and flushing. The effects are mixed and results cannot be guaranteed but facial flushing has become an indication for thoracoscopic sympathectomy. When the procedure is done specifically for facial flushing with specific attention to the top of the 2nd rib, the results are good.


During workup other causes of excess sweating should be considered, e.g. hyperthyroidism, carcinoid. Perimenopausal patients and those who have blotchy slow rising flushing should be avoided. Psychological status should also be considered and expectations not exaggerated. It is important to point out that this is a major thoracic procedure with all its potential anaesthetic and surgical complications.

Patients need to be warned of pneumothorax, chest drain insertion, bleeding, thoracotomy as for all thoracoscopic procedures. Specifically Horner’s syndrome (constriction of the pupil, ptosis of the upper eyelid, enophthalmos, absence of sweating on the face and neck and some disturbance of acccommodation), compensatory sweating (especially back and torso) and failure or mixed result of the procedure should be discussed.


Anaesthesia

This is one of the few thoracoscopic procedures for which we use carbon dioxide insufflation. We have used two anaesthetic techniques:

  1. 1.Jet ventilation

  2. 2.Sequential lung deflation using double lumen endotracheal tube

The latter is more widely available and works satisfactorily. Jet ventilation allows the lung to remain partially inflated with less re-expansion dysfunction. If an air leak has been created during the first side, it is less likely to tension with the jet. When using double lumen ETT with sequential lung collapse it is important to let the first lung fully re-expand and stabilise for a number of minutes before collapsing the second lung.


Position

The patient is placed supine with both arms abducted. The head of the table is raised to encourage the lungs to fall away from the apex. To allow an extensive sympathectomy covering the axilla and back the patient needs to be semi-erect


Equipment

  1. Two 5 mm blunt tipped trocar and cannulae (Ethicon Endopath 355SD)

  2. 5 mm 300 telescope

  3. 5 mm spatulated diathermy blade (Storz blunt dissecting spatula 26775 UE)

  4. CO2 insufflation tube

  5. 20 ml syringe of saline

  6. A 5 mm diathermy hook for adhesions

  7. Irrigator/sucker available in a sterile pack in case of bleeding


Incisions and insufflation


Axillary incision

  1. 5 mm incision in mid axillary line just above the level of the lowest hair (approximately the 3rd intercostal space)

  2. 5 mm trocar and cannula introduced at right angles to the rib cage (remember that the apex of the hemithorax is curving inwards at this level. The angle of entry is slightly downwards rather than horizontal)



Insufflation

  1. Pass the telescope into the cannula and check that it is in the pleural cavity.

  2. Insufflate approximately 1000cc of CO2 (800cc in a smaller lady) via the side tap of the cannula. Ensure that the insufflation pressure does not exceed 3 kPa.

  3. Swing the camera inferiorly without torquing the telescope and advance the telescope towards the apex.


Anterior incision

  1. 5 mm incision in mid-clavicular line 1st intercostal space

  2. Introduce another 5 mm trocar and cannula aiming slightly away from the mediastinum (this can be observed with the telescope)

  3. Pass the diathermy spatula into the pleural cavity

Jim McGuigan now routinely uses two axillary incisions. The diathermy spatula is passed parallel to the telescope. Early experience suggests that this not only improves the cosmetic result but reduces postoperative pain due to less manipulation of the port trocar.



Procedure


Identification of the chain

The sympathetic chain runs along the necks of the ribs. It lies just lateral to the superior intercostal vein. Identify this vein and follow it towards the cupola of the pleura. The upper extent of the vein the second intercostal vein which lies under the second rib. The stellate ganglion lies above and below the first rib neck which lies deep to a yellow fat pad just below the pulsing subclavian artery.





The chain is best felt rather than seen. Rolling the spatula over the chain will identify it (see video)


Transection of the sympathetic chain

    1. Having identified the chain, at the level of the second rib for palmar hyperhidrosis, perform a “test burn” out along the shaft of the rib, well out of harm’s way. Check the level of the cautery so that there is minimal spread. Keep the level low to prevent too much smoke This will be particularly relevant when close to the stellate ganglion.

    2. Dissect the chain carefully by cauterising the pleura with the diathermy spatula

    3. Divide the chain with gentle pressure against the rib

    4. Extend the cut out laterally to divide any collateral nerves passing lateral to the main chain at the level of the second rib

    5. Extending medially has to be done carefully as the vein is very close.

  1. Remaining sympathectomy

    1. Cut across the chain over the necks of ribs 3 and 4 as required.

    2. Further collaterals can be divided by extending the cut laterally over the third rib

    3. Spot diathermy over the chain between ribs but be careful not to damage the intercostal vessels lying just beneath each rib.



  2. Extent of sympathectomy

  3. Palmar hyperhidrosis - the chain should be divided over second and third ribs with diathermy from the top of the 2nd to the bottom of the 3rd. The preganglionic fibres supplying the upper limb are derived from the upper thoracic segments of the spinal cord, probably T2-6. Most of the vaso-constrictor fibres supplying the arteries of the upper limb emerge from the cord in the ventral roots of the 2nd and 3rd thoracic nerves. These fibres ascend the sympathetic chain to synapse with cells mainly in the cervico-thoracic (stellate) ganglion, whence post-ganglionic fibres pass to the brachial plexus, mainly the lower trunk.

  4. Axillary hyperhidrosis - the chain should be divided at least over third and fourth ribs with diathermy from the top of the 2nd to the bottom of the 4th. A more complete axillary sympathectomy will be achieved by extending to the 5th rib. Avoiding the 2nd (when palmar sweating is not a problem) will reduce compensatory hyperhidrosis.

  5. Facial blushing - the chain should be divided over second rib with diathermy from the top of the 2nd to the bottom of the 2nd. Careful diathermy above the top of the 2nd rib may improve the effect but is best carried with bipolar cautery which will not spread.

Compensatory torso sweating may be reduced by continuing the sympathectomy below the fourth rib. This does run the risk of bradycardia but some patients are prepared to take the risk when compensatory sweating would be unacceptable. The lung often will sit over the fourth rib. It can be retracted with a retractor passed through a further port. However, with experience it is possible to bring the camera in close and use it to push the lung down slightly.


Intra-operative problems

  1. 1.Bleeding

    1. 1.Best prevented by cauterising lightly before applying physical pressure on pleural vessels

    2. 2.Pressure with the spatula will control most bleeding as it will usually be venous.

    3. 3.Cautery as required

    4. 4.Use sucker irrigator to clear view

    5. 5.Perform axillary thoracotomy if necessary

  2. 2.Adhesions

    1. 1.Be careful introducing trocars

    2. 2.Divide with diathermy hook

    3. 3.Adhesions frequently lead to air leaks so have a low threshold for placing a drain. A 16Fr drain will pass easily down a 5 mm cannula

    4. 4.If adhesions are bad enough the procedure may ned to be abandoned or a thoracotomy performed.

  3. 3.Failure of lung to collapse

    1. 1.Check that the CO2 has actually entered the pleural cavity

    2. 2.Check position of double lumen tube and aspirate secretions

    3. 3.Sometimes the surface tension between the lung and the pleura will prevent it dropping. The telescope can be used to break the tension and the lung will fall away.

  4. 4.Pneumothorax

    1. 1.As long as you have not let air in through the cannulae any residual gas will be CO2. This will be absorbed over a few hours and no intervention will be needed other than a check X-ray after 4 hours.

    2. 2.If in doubt a drain can be inserted (as above).

  5. Re-inflation of the lung and closure

  6. Remove anterior cannula and pinch the wound closed.

  7. Apply the 20 ml saline syringe to the side arm of the axillary cannula

  8. Ask anaesthetist to gently re-inflate the lung while you observe both the lung with the telescope and the gas bubbling through the syringe.

  9. As the lung expands, remove the telescope.

  10. Gentle percussion on the chest wall will encourage all gas to escape.


  1. The skin can be closed with single subcuticular sutures or skin clips.

  2. Local anaesthetic (0.25% Marcaine or Chirocaine) is injected around the wound sites.


Postop treatment and followup

  1. One or two doses of narcotic may be needed but patient controlled analgesia system (PCAS) is usually not needed.

  2. Check chest X-ray at 4 hours.

  3. Home later that evening or, more usually, the following morning.

  4. Sutures can be removed at 5 days as an outpatient.

  5. Return to work after a week.


Results

  1. Palmar hyperhidrosis - usually very good. the hand is warm and dry at the end of the procedure.

  2. Axillary hyperhidrosis - mixed results due to variable innervation and difficulty getting to lower end of 4th and 5th rib.

  3. Facial blushing - mixed results due to variable innervation and caution one must apply when operating near stellate ganglion.

 
Videohttp://www.mactheknife.org/Videos/Sympathectomy.html