Video-Assisted Thoracoscopic Surgery (VATS)

Video-assisted thoracoscopic surgery (VATS) is minimally invasive thoracic surgery that does not use a formal thoracotomy incision. VATS provides adequate visualization despite limited access to the thorax, allowing the procedure to be performed in patients who are debilitated or have marginal pulmonary reserve.[1]

VATS is principally employed in the management of pulmonary, mediastinal, and pleural pathology. Its main benefit has been the avoidance of a thoracotomy, which allows a shorter operating time, less postoperative morbidity, and earlier return to normal activity than can be achieved with a thoracotomy.

The first clinical application of VATS dates back to 1913, when adhesiolysis was performed to enhance pneumothorax therapy of tuberculosis via a cystoscope introduced into the pleural cavity.[1] VATS is now an established and widely used minimally invasive approach to diseases of the chest.

Compared with conventional thoracotomy, VATS lobectomy has resulted in better preservation of pulmonary function.[2] In addition, overall surgical mortality is 0-2% for VATS, which compares favorably with mortality for the conventional thoracotomy technique.[3, 4]

VATS is used in both diagnostic and therapeutic pleural, lung, and mediastinal surgery. Specific indications include the following:

• Stapled lung biopsy
• Lobectomy, segmentectomy, ^[5] or pneumonectomy
• Resection of peripheral pulmonary nodule
• Evaluation of mediastinal tumors or adenopathy
• Pleural biopsy
• Bullectomy
• Treatment of recurrent pneumothorax
• Management of loculated empyema
• Pleurodesis of malignant effusions
• Repair of a bronchopleural fistula
• Chest trauma (mainly diaphragmatic injuries)
• Pericardial window
• Sympathectomy
• Truncal vagotomy

Although the use of thoracoscopy for pulmonary metastesectomy has been controversial, some authors have found it to be efficacious and safe.[6, 7]  In a survey carried out by the European Society of Thoracic Surgeons (ESTS), 72% of respondents preferred a minimally invasive approach to metastasectomy for pulmonary metastases in colorectal cancer patients.[8]

The use of VATS to accomplish cardiac denervation of refractory ventricular arrhythmias and electrical storms has been described.[9]

Absolute contraindications include the following:

• Markedly unstable or shocked patient
• Extensive adhesions obliterating the pleural space
• Prior talc pleurodesis

Relative contraindications include the following:

• Inability to tolerate single-lung ventilation
• Previous  thoracotomies
• Extensive pleural diseases
• Coagulopathy
• Prior radiation treatment for thoracic malignancy; plan to resect

In a prospective observational study evaluating long-term survival outcomes of VATS lobectomy with lymphadenectomy in 109 patients with non-small cell lung cancer (NSCLC) who were followed for a median of 27 months, Luan et al reported overall survival rates of 100% after 1 year, 85.9% after 2 years, 65.3% after 3 years, 55.9% after 4 years, and 55.9% after 5 years.[10]  

Equipment for video-assisted thoracoscopic surgery (VATS) includes the following:

• 5- or 10-mm video thoracoscope, with a 0º or 30º lens and a three-chip charge-coupled device video camera
• Sponge-holding forceps
• Long-blade diathermy pen
• Endoscopic biopsy forceps (for simple pleural biopsy)
• Endoscopic staple-transection devices (for lung wedge resection)
• Rigid or flexible trocar cannula and/or sterile plastic bag
• Thoracotomy tray
• Chest tube drainage device with water seal
• Suction source and tubing
• Sterile gloves
• Sterile drapes
• Gauze squares

Anesthesia

For most VATS procedures, general anesthesia with selective single-lung ventilation using a double-lumen endobronchial tube is preferred. Left-side intubation is usually performed unless a left pneumonectomy is anticipated. A single-lumen endotracheal tube with a bronchial blocker is an acceptable alternative.

For treatment of pleural effusions and sympathectomy, single-lung ventilation with low tidal volumes is a better option and allows adequate visualization of the pleural space. Moreover, CO2 can be insufflated to facilitate partial collapse of the lung.

For pediatric patients, a single-lumen tube is used with the tip placed into the contralateral mainstem bronchus.

Thoracoscopic evaluation of an awake, nonintubated, nonventilated patient in an ambulatory setting under monitored anesthesia care has been described.[11]  Irons et al, in a study of 73 patients who underwent elective minor VATS, found nonintubated general anesthesia with spontaneous ventilation via a supraglottic airway device to be a feasible alternative to intubated general anesthesia.[12]

A study by Lee et al found that during nonintubated VATS, transcutaneous CO2 monitoring was more accurate in detecting hypercapnia than end-tidal CO2 monitoring.[13]

For major lung resections, typed and crossmatched blood should be available.

Two large-bore intravenous (IV) lines and an arterial line should be also placed.

Positioning

The patient is turned to a full lateral decubitus position, and the operating table is flexed to widen the rib spaces on the operation side. The positions of the surgeon and assistant depend on the site of the pathology as suggested by preoperative imaging. The surgeon stands facing the site of the pathology, with the camera-holding assistant on the same side. The television monitor is positioned so that the surgeon, the site of pathology, and the monitor are aligned to allow the surgeon to look straight ahead when operating.

Alternatively, the patient can be positioned supine with a roll under the back to bump him or her up and provide access to the pleural space from a more anterior approach.

One to four incisions are used in video-assisted thoracoscopic surgery (VATS) procedures. For drainage of pleural effusions, it is sufficient to use one small incision to accommodate the 10-mm offset scope, evacuate the effusion, and use the talc poudrage and chest tube. For a VATS lobectomy, four incisions have commonly been used, with the largest being about 4 cm long. However, there is growing interest in and acceptance of uniportal approaches to lobectomy in selected patients.[14, 15]

Incisions are made in a triangulated fashion, typically at least 5 cm apart so that the instruments do not cross. (See the image below.) This so-called baseball diamond approach aligns the camera and instruments to manipulate the lung and perform a resection. For VATS thymectomy, a subxiphoid and subcostal arch approach has been described as an alternative to a lateral intercostal approach.[16, 17]

Single-port approaches have been employed for other VATS procedures besides lobectomy.[18] A meta-analysis by Xu et al found that single-port VATS might have certain advantages over three-port VATS for primary spontaneous pneumothorax, though studies of higher quality and greater scale would be needed to confirm this.[19] ​Liu et al described five cases in which uniportal VATS parietal pleurectomy proved safe and feasible in patients with complex tuberculous pneumothorax.[20] A study by Jiang et al found that single-port VATS was not inferior to three-port VATS for mediastinal cystectomy.[21]

For single-incision cases, curved instruments are helpful.

Procedural limitations may include difficulty in controlling bleeding and a lack of intraoperative palpation.

Various applications of VATS are illustrated in the images and video below.

Indications for conversion from VATS to thoracotomy

Indications for conversion from VATS to thoracotomy include the following:

• Inability to achieve single-lung ventilation
• Extensive pleural adhesions
• Uncontrolled or significant intraoperative bleeding
• Inability to identify a target lesion for biopsy
• Technical difficulties with or primary failure of video equipment and/or endoscopic instruments

A study by Vallance et al found that with increasing experience and expertise, the rate of unplanned conversion from VATS to thoracotomy could be brought down to about 10%.[22]  

Complications may include the following:

• Persistent air leakage
• Bleeding from pulmonary vessels ^[4]
• Intercostal nerve damage due to insertion of instruments through the ports
• Complications from single-lung ventilation, including respiratory insufficiency or postoperative reexpansion pulmonary edema
• Tumor implantation following VATS