Thoracic Sympathectomy

The sympathetic nervous system controls automatic body functions, including sweating and the widening of blood vessels in the skin. Its nerve chain runs along both sides of the spine inside the chest, with small nerve junctions, called ganglia, next to each rib. Signals passing through particular levels of this chain switch on the sweat glands of the hands, armpits and face and cause facial flushing. In primary hyperhidrosis these glands are overstimulated without an underlying illness, so sweating is far greater than needed to control body temperature. Thoracic sympathectomy interrupts the chain at a chosen level, by cutting, burning or placing small clips on it, so that the signals no longer reach the target area. The level chosen depends on the problem: higher levels mainly affect the face and blushing, and levels slightly lower down mainly affect the hands and armpits. Lower levels are thought to cause less compensatory sweating.

Sympathectomy is considered for severe primary hyperhidrosis of the palms that interferes with work, study, writing, using devices or social contact, and that has not responded to other treatments. These include strong aluminium-based antiperspirants, iontophoresis, in which a weak electric current is passed through water in which the hands are placed, tablets that reduce sweating, and botulinum toxin injections. It is also used, with more caution, for facial sweating and for severe facial blushing that seriously affects daily life. Results for armpit sweating alone are less predictable, and injections or local treatments are usually preferred there. Excessive sweating of the feet is not reliably improved by thoracic surgery. Before surgery, secondary causes of sweating, such as an overactive thyroid, infection, some medicines or other illnesses, should be excluded, and a dermatologist or the surgeon should confirm that the pattern fits primary hyperhidrosis.

ETS is done under general anaesthesia with a breathing tube that allows one lung at a time to be briefly deflated. You lie on your back or slightly sitting up with your arms raised. The surgeon makes one or two small cuts, usually under five to ten millimetres, in the armpit on one side and passes a thin camera into the chest. The deflated lung moves away, the sympathetic chain is seen running over the ribs, and it is divided, burnt with a heat probe or closed with small titanium clips at the planned level. The lung is then reinflated to push out the air, the cuts are closed, and the same steps are repeated on the other side. Many surgeons check the warming of the hands during the operation, which shows that the nerve signals have been interrupted. Both sides together usually take about one to two hours, and a drain is often not needed.

Good candidates are adults, or sometimes older teenagers, with severe primary palmar hyperhidrosis or disabling blushing that has not responded to other treatments, who are in good general health and who fully understand the risk of compensatory sweating. People with marked obesity, previous chest surgery or lung disease that has scarred the lung to the chest wall, a slow heart rate or certain heart conditions may not be suitable or may need extra assessment. Before surgery you will usually have a medical review, blood tests including thyroid function, a chest X-ray and sometimes a heart tracing. Many surgeons ask you to think the decision over for a while after the first consultation, and some suggest that you discuss it with a person who has had the operation. International patients can usually have an initial video consultation and share their treatment history in advance.

You wake up with warm, dry hands in most cases. A chest X-ray is usually taken after surgery to check that both lungs have fully reinflated, and most people go home the same day or the next morning. Some chest or shoulder discomfort and a tight feeling when breathing deeply are common for a few days and are managed with simple painkillers. You can walk and do light activities straight away, and most people return to desk work within about a week, avoiding heavy lifting and strenuous sport for about two weeks. Flying is usually considered safe after about five to seven days, once the surgeon has confirmed that no air remains around the lungs. Compensatory sweating may not be clear in the first days, so it is helpful to keep in contact with your surgeon over the following months, by video if needed.

The main drawback is compensatory sweating, which is the rule rather than the exception: most people notice increased sweating on the back, chest, abdomen, thighs or legs after surgery. For many it is mild and acceptable, but for some it is heavy, especially in heat or exercise, and a minority regret the operation because of it. It cannot be predicted reliably and usually persists, and there is no dependable way to reverse it. Other risks include a pneumothorax that may need a drain, bleeding, nerve pain in the chest wall and, rarely, a drooping eyelid with a small pupil on one side, called Horner's syndrome. Some people notice sweating when eating certain foods, or hands that become too dry. Sweating of the hands can return over time in a small number of people. For palmar hyperhidrosis, the dryness of the hands is usually immediate and long-lasting; results for blushing and armpit sweating are less consistent.