Approach Considerations
The operative technique of thoracoscopic wedge resection (TWR) follows the same basic principles as those of thoracotomy except for minimal invasiveness and use of a thoracoscope. The operating surgeon should never hesitate to convert to open thoracotomy when complete resection of the lesion is in doubt. Conversion to thoracotomy is imperative in following conditions: [24]
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Massive bleeding
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Inability to locate the lesion
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Hilar or mediastinal lymphadenopathy
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The patient’s inability to tolerate single-lung ventilation
Thoracoscopic Wedge Resection
The steps of TWR are summarized below. [21, 25, 26, 27, 28, 29, 30, 31, 32, 33]
After anesthesia and positioning, the hemithorax is cleaned with antiseptics and sterile drapes placed. Considering the location of the pathology, the thoracoscope and instruments are positioned strategically to provide the best ergonomics for the surgeon in order to optimize the results.
Conventionally, wedge resections are performed with 3 small incision sites to accommodate the ports (5-10 mm)—one camera port and two ports for instruments. However, single-port VATS with the use of flexible instruments are becoming popular. [21, 28] A comparison study by Mizukami et al suggested that for pulmonary wedge resection, single-port VATS offers better pain control and cost-effectiveness than three-port VATS. [34]
The incision site depends on location of pathology. Incisions are placed at the upper end of ribs to avoid injury to the neurovascular bundle.
The primary incision site (generally for the thoracoscope [camera port]) is at the seventh or eighth intercostal space at the anterior to midaxillary line, which gives a panoramic view of entire lung. A trocar is introduced into the thoracic cavity, followed by insertion of the thoracoscope (see images below).
The second incision site is the anterior fourth and fifth intercostal space at the midclavicular or anterior axillary line. The third incision is posterior, at the fifth and sixth intercostal space adjacent to the scapula. These triangulated incisions are similar to a baseball-diamond concept. Ports are placed far enough from each other to avoid crowding of instruments. If conversion to open or minithoracotomy is required, connecting the anterior and posterior port sites provides incision access, and the inferior port is used for chest tube insertion.
Localization of the pathologic site is crucial, although this is arduous in some patients, especially those with small and deep lesions. The limited ability to digitally palpate the lung increases the risk of missing satellite lesions or other related pathology. Target lesions are identified based on visceral pleural changes such as puckering, dimpling, raised lesions over a deflated lung, increased vascularity, or overlying pleural adhesions. Expert surgeons seldom miss target lesions. For localizing lesions, preoperative CT-guided needle placement, hook-wire localization, or placement of radio-opaque marker (eg, methylene blue) can be used for guidance and lesion detection intraoperatively with fluoroscopy. [25, 26, 27]
Once the lesion is localized, several techniques may be used to resect the lung. The criterion standard method is resection with mechanical endoscopic staplers (see image below).
This is used to staple and resect the lung simultaneously (see images below).
Small lesions may be excised with single staple run, while larger lesions require 3-dimensional planning with numerous staple runs. The deflated lung tissue can be rotated from apex or base to lie over hilum to allow straight staple cuts. Other techniques include scalpel or diathermy resection with endoscopic suturing or a neodymium:yttrium-aluminum-garnet (ND:YAG) laser alone or in conjunction with mechanical staplers.
Endoscopic saline-enhanced thermal sealing is a new technology using a floating pen device or a grasper to resect the lung. Hemostasis is achieved with thermal sealing and does not require suturing or stapling. Unlike conventional cautery, this technique does not char the tissue.
The resected specimen is removed through the anterior port using wound protectors. Larger specimens are removed using endoscopic bags to prevent tumor implantation. After resection, the lung is examined for air leaks, and a chest tube is placed through the inferior port and connected to a water seal.
As an alternative to chest tube placement in selected patients, chest drainage may be provided by a 7-Fr double-lumen central venous catheter along with a prophylactic air-extraction strategy. A prospective randomized controlled trial by Wei et al found that acute pain after lung wedge resection through VATS was significantly lower with central venous catheter drainage than with conventional chest tube drainage. [35]
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Trocar.
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Thoracoscope insertion.
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EZ45 endostapler.
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Rigid thoracoscope, 10 mm.
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Thoracoscopic wedge resection.
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Thoracoscopic wedge resection.
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Thoracoscopic wedge resection.
