Key points

Introduction and history

The sympathectomy, a surgical procedure creating a break in the sympathetic signaling pathway, was pioneered in 1889 and at the time was used to treat conditions such as epilepsy, exophthalmic goiter, idiocy, and glaucoma. Although no longer indicated to treat these conditions, more advanced versions of the sympathectomy have found a place in the treatment of hyperhidrosis. Hyperhidrosis is a skin disorder characterized by sweating in excess of what is necessary for thermoregulation of the body. This excessive sweating often involves the craniofacial region, axillae, palms, or soles and can be classified as either primary, which is idiopathic, or secondary to a medical condition or medication. Hyperhidrosis can be further classified as focal, regional, or generalized, with most patients suffering from primary focal hyperhidrosis. Various treatment modalities for the condition exist, including localized topical and injectable treatments, systemic medical treatments, and several surgical treatments. The focus of this article is endoscopic thoracic sympathectomy (ETS) as management for primary focal hyperhidrosis.

Today the main indications for the sympathectomy are blushing, flushing, and hyperhidrosis. Because hyperhidrosis is thought to potentially be caused by excessive sympathetic stimulation, the intention of ETS is to interrupt that signal by cutting or clipping the involved sympathetic nerves. The procedure is noted to have particular success in the improvement of palmar hyperhidrosis. Initially, the sympathectomy was an open procedure, but it has evolved into an endoscopic surgical technique. The main goal over time has been to maintain efficacy while minimizing the invasiveness of the procedure in an effort to reduce the risk of complications, specifically the development of compensatory sweating.

Introduction and history

The sympathectomy, a surgical procedure creating a break in the sympathetic signaling pathway, was pioneered in 1889 and at the time was used to treat conditions such as epilepsy, exophthalmic goiter, idiocy, and glaucoma. Although no longer indicated to treat these conditions, more advanced versions of the sympathectomy have found a place in the treatment of hyperhidrosis. Hyperhidrosis is a skin disorder characterized by sweating in excess of what is necessary for thermoregulation of the body. This excessive sweating often involves the craniofacial region, axillae, palms, or soles and can be classified as either primary, which is idiopathic, or secondary to a medical condition or medication. Hyperhidrosis can be further classified as focal, regional, or generalized, with most patients suffering from primary focal hyperhidrosis. Various treatment modalities for the condition exist, including localized topical and injectable treatments, systemic medical treatments, and several surgical treatments. The focus of this article is endoscopic thoracic sympathectomy (ETS) as management for primary focal hyperhidrosis.

Today the main indications for the sympathectomy are blushing, flushing, and hyperhidrosis. Because hyperhidrosis is thought to potentially be caused by excessive sympathetic stimulation, the intention of ETS is to interrupt that signal by cutting or clipping the involved sympathetic nerves. The procedure is noted to have particular success in the improvement of palmar hyperhidrosis. Initially, the sympathectomy was an open procedure, but it has evolved into an endoscopic surgical technique. The main goal over time has been to maintain efficacy while minimizing the invasiveness of the procedure in an effort to reduce the risk of complications, specifically the development of compensatory sweating.

Anatomy and physiology

The sympathetic nerves that control sweating originate in the spinal cord between segments T1 and L2. The distribution is segmental and variable, with sympathetic fibers from T1 generally supplying the head, T2 the neck, T3 to T6 the thorax, T7 to T11 the abdomen, and T12 to L2 the legs.

Experiments performed in the 1950s found that most of the sympathetic outflow to the hand originates from T2 to T3. Signaling from these levels may also travel via an alternative pathway, the nerve of Kuntz. Although not present in all people, the nerve of Kuntz forms a connection from the second intercostal nerve to the first thoracic ventral ramus, allowing signals to reach the brachial plexus without traversing the sympathetic trunk. Therefore, complete denervation of the hand requires surgical division of the sympathetic chain above the T2 ganglion and below the T3 ganglion as well as possible transection of Kuntz’s nerve. When axillary hyperhidrosis exists with palmar hyperhidrosis, surgery may be extended to include the T4, T5, or even T6 ganglion. The cervicothoracic ganglion, or stellate ganglion, is formed by the fusion of the inferior cervical ganglion and the first thoracic ganglion. It has been implicated in hyperhidrosis but is often left untouched during ETS to avoid Horner’s syndrome. More specific information regarding these techniques will be addressed in a later section of this review.

Endoscopic lumbar sympathectomy is has been used for plantar hyperhidrosis. Sympathetic outflow to the lower extremities originates at T12, L1, and L2 and, therefore, can be interrupted by division of the sympathetic trunk at the L3 level or removal of the ganglia from L2 to L4. In surgery, the first lumbar ganglion often is left untouched in an attempt to preserve sexual function.

Nomenclature

Various terms have been used to describe origins of sympathetic innervation with regard to the exact location of surgical intervention. Some authors describe the vertebral level (T), whereas others describe sympathetic outflow by its relationship with the nearest rib (R). Recently, the International Society on Sympathetic Surgery and The Society of Thoracic Surgeons General Thoracic Task Force on Hyperhidrosis acknowledged the need for uniform language to describe the location of ETS in an effort to make comparisons between procedures more accurate. A consensus on terminology, as determined by International Society on Sympathetic Surgery and the Society of Thoracic Surgeons in 2011, indicates that standard nomenclature using rib orientation is the most precise way to describe ETS. An operative note would describe the procedure by noting the rib number (for example, R3 is the third rib) and the location (top, bottom, or both) where the denervation occurred relative to the rib. For example, a procedure at R4, above denotes nerve interruption above the fourth rib. Both R and T nomenclature, including the use of R nomenclature without the denotation of above and below, are used in the literature and are so used in this report.

Indications

Referral for ETS may be indicated when medical therapies and, when appropriate, local surgery have failed or are contraindicated. Other treatments for axillary hyperhidrosis include topical antiperspirants such as aluminum chloride; injected botulinum toxin; oral anticholinergic medications; and local surgeries including simple excision, curettage, and liposuction and procedures that combine these techniques. More recently, microwave and ultrasound technologies have also been used to treat axillary hyperhidrosis. For palmar hyperhidrosis, standard treatments include topical aluminum chloride, oral anticholinergic medications, iontophoresis, and botulinum toxin. For craniofacial hyperhidrosis, treatments include topical aluminum chloride, botulinum toxin, and oral medications such as anticholinergics, clonidine, propranolol, and diltiazem. The algorithm for treatment strategies in plantar hyperhidrosis is similar to that of palmar hyperhidrosis, with ultimate referral for endoscopic lumbar sympathectomy rather than thoracic sympathectomy.

Based on randomized trials and nonrandomized comparisons, the Society of Thoracic Surgeons has described an ideal candidate for ETS :

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  Patients with onset before 16 years of age who are younger than 25 years at time of surgery

  
  
  
  
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    with body mass index less than 28

    
    
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    reporting no sweating during sleep

    
    
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    without significant comorbidities and

    
    
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    with resting heart rate greater than 55 beats per minute.

  
  

Additional indications for ETS include :

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  Arteriospastic disorders: eg, Raynaud’s disease and acrocyanosis

  
  
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  Occlusive arteriolar disorders: eg, thrombongiitis obliterans

  
  
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  Some neurologic disorders: eg, posttraumatic sympathetic dystrophy

  
  
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  Intractable pain: eg, angina and complex regional pain syndrome

  
  
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  Possibly social phobia

Selection criteria for randomized trials exploring surgical treatment of hyperhidrosis frequently include only severe and debilitating primary palmar hyperhidrosis with serious negative repercussions on social life and professional activity. According to the Society of Thoracic Surgeons Expert Consensus, “only a small percentage of patients should be considered for surgical treatment.”

Techniques

The goal of a sympathectomy of any kind for hyperhidrosis is to disconnect the eccrine sweat glands from the sympathetic signals that trigger them to initiate sweating. Initially, open procedures were performed, with approaches including anterior supraclavicular, posterior paravertebral, posterior midline, anterior thoracic, axillary thoracic, or axillary extrathoracic with first rib resection. In 1951, Kux first described an endoscopic transthoracic approach, and this technique is now the standard of care for hyperhidrosis.

Current techniques involve the destruction of the bilateral thoracic sympathetic ganglia via endoscopic resection, ablation, or clipping ( Fig. 1 ). The procedure requires general anesthesia, but most patients are able to go home the day of the procedure. There are reports of the use of local anesthesia for the procedure, but this is not generally recommended.

Current techniques for endoscopic thoracic sympathectomy.

( Courtesy of Albert Ganss, International Hyperhidrosis Society, Quakertown, PA; with permission.)

Surgical technique can vary based on surgeon preference and anatomic location of hyperhidrosis. Recent consensus recommendations from the Society of Thoracic Surgeons are to interrupt the sympathetic chain above the third rib for palmar hyperhidrosis, above the fourth and fifth rib for axillary hyperhidrosis, and above the third rib for craniofacial hyperhidrosis ( Table 1 ).

Traditionally, for isolated palmar hyperhidrosis, an incision of less than 1 cm is made in the midaxillary line, through which the endoscope and instruments are inserted. Carbon dioxide insufflation may be used to partially collapse the lung, improving visualization. The anatomy is examined, and the sympathetic chain is divided, often just above T2 and below the stellate ganglion. Additional sites may be interrupted, including other ganglia and nerves of Kuntz if present. The ends of the nerves are separated to allow at least a 1-cm gap to reduce nerve regrowth and recurrence of hyperhidrosis. Sympathetic tone to the hand is assessed with a laser Doppler palmar blood flow device or finger temperature probe. A suction catheter is used to evacuate the pneumothorax if the lung has been collapsed; otherwise, intrapleural air is aspirated through tubes. A chest x-ray is obtained after the procedure to ensure proper lung inflation and minimal intrapleural air. The procedure generally takes less than an hour to complete.

Researchers have attempted to analyze whether transection, resection, ablation, or clipping is a superior technique in ETS. No clear differences have been found. Rather, the results are dependent on whether the correct level of division was achieved and if there was enough separation between the ends of the chain to avoid nerve regrowth.

A few small prospective studies out of China have recently found an effective new technique using a transumbilical endoscopic approach to achieve thoracic sympathectomy. In one study, 66 patients with severe palmar hyperhidrosis presented for thoracic sympathectomy. Thirty-four of these patients received transumbilical thoracic sympathectomies through a 5-mm umbilical incision using an ultrathin gastroscope; the remaining patients were treated with traditional needlescopic thoracic sympathectomy. All of the patients reported that the procedure successfully treated their hyperhidrosis. Patients receiving the transumbilical procedure reported reduced pain and paresthesia; this is possibly explained by the absence of a chest wall incision and subsequent lack of manipulation of intercostal space with trocars. This transumbilical technique showed a superior aesthetic outcome when compared with the traditional group, although the operating time of the surgery was slightly longer.

Use of a voice-controlled robotic arm has been compared with use of a human camera-holding assistant. There was no difference between groups in terms of accidents, pain, general satisfaction, anhidrosis, length of hospitalization, or compensatory hyperhidrosis (CH). The robotic group had reduced contact of the laparoscopic lens with mediastinal structures but also had longer operating time, suggesting that the robotic camera is as safe as a human assistant but less efficient.