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Thoracoscopy was first described in the early 1900s, and by the mid-1990s, thoracoscopic lung biopsy had become accepted as a superior technique for obtaining tissue in cases of interstitial lung disease or malignancy. Thoracoscopy has also become the preferred approach in the treatment of most mediastinal masses in children. However, the thoracoscopic approach for lobectomy, because of the complex nature of the disease process and the anatomic dissection, has not been as readily accepted. Improvements in instrumentation and operative technique over the past two decades have made thoracoscopic lobectomy for congenital and acquired lung disease in children a safe and viable option. In most cases, it is the preferred approach to avoid the morbidity of a thoracotomy incision.
Indications for Workup and Operation
Indications for lobectomy include both congenital and acquired disease. Congenital lesions include congenital pulmonary adenomatoid malformation (CPAM), intralobar and extralobar bronchopulmonary sequestration (BPS), congenital lobar emphysema (CLE), and more rare causes of congenital airway obstruction that result in lung parenchymal injury. Acquired etiologies include severe bronchiectasis, right middle lobe syndrome, necrotizing pneumonia, and malignancy. In most cases, the preoperative evaluation consists of a chest radiograph and computed tomography scan. Occasionally, other studies such as a ventilation-perfusion scan may be needed to determine the degree of lung injury and whether a lobectomy is possible. Rarely, an aortogram or a magnetic resonance angiogram helps identify a systemic vessel or aberrant vascular supply, as in the case of a sequestration. Bronchoscopy should be performed in cases where abnormal bronchial anatomy or obstruction is suspected.
The procedure varies slightly depending on the lobe being resected, but all procedures are performed with the patient in a lateral decubitus position. The room and personnel setup for a left lower lobectomy are shown in Figure 32-1 . The surgeon and assistant stand at the patient’s front with the monitor over the patient’s back. In all cases, single-lung ventilation is desirable if at all possible, but a successful lobectomy can be performed just using CO 2 insufflation to collapse the lung. In larger patients, a double-lumen endotracheal tube is beneficial. In infants and smaller children, single-lung ventilation is obtained by mainstem intubation of the contralateral side or by use of a bronchial blocker. A first- or second-generation cephalosporin is administered for prophylaxis in patients not already on antibiotics.
It is important to understand the anatomy of the structures in the various fissures. The anatomy of the fissure between the upper and lower lobes of the left lung is depicted in Figure 32-2 . The anatomy of the structures in the major and minor fissures between the three lobes of the right lung is seen in Figure 32-3 . When working anteriorly to posteriorly in the fissures, the surgeon encounters the arteries to the lobes first, followed by the bronchial structures. The lobar veins are not adjacent to the arteries and bronchi in the fissures but are seen more inferiorly in the mediastinum.
The chest cavity is initially insufflated through a Veress needle placed in the midaxillary line at the fifth or sixth interspace. CO 2 is insufflated at a low flow and pressure to help effect complete collapse of the lung. A flow of 1 L/min and a pressure of 4 to 6 mm Hg is maintained throughout the operation. Occasionally, it is necessary to use a higher pressure initially to facilitate complete collapse of the lung. Thus, it is important to use valved ports so that a mild tension pneumothorax is maintained. In infants, a 4-mm reusable port and a short (20-cm), 4-mm, 30-degree lens is used for the telescope. (If this is not available, then a short, 20-cm, 5-mm telescope can be used.) A 3-mm reusable port is used for the left-hand instrument and a 5-mm port for the right hand. This larger port allows insertion of the 5-mm stapler (Bolder Surgical, Louisville, CO), endoscopic clips, or suture as needed. It is also the port site where the specimen will be removed. We prefer the radially expandable 5-mm ports as they prevent trauma to the intercostal vessels and nerves.
After removal of the Veress needle, the first port (4 mm) is introduced and the telescope is inserted to determine the position of the major fissure and to evaluate the lung parenchyma. The tendency is to place this port too far posterior or too high. If that occurs the port can be removed and the position modified more anteriorly or an interspace up or down while using the same skin incision. The location of the fissure dictates the positioning of the other ports. These working ports (3 mm or 5 mm) are inserted in the anterior axillary line between the fifth and the eighth or ninth interspaces ( Fig. 32-4 ). The size of the cannulas depends on the size of the patient and the equipment to be used. In larger patients, if the 12-mm endoscopic stapler is to be used, a 12-mm port is situated at the lower port site in the largest interspace possible that will align with the front edge of the fissure. This is usually the eighth interspace. In smaller patients, the 5-mm stapler or endoscopic clips are employed, and these require only a 5-mm cannula.
The first step in a lower lobectomy is mobilization of the inferior pulmonary ligament. During this mobilization, care is taken to look for a systemic vessel arising from the aorta in patients suspected of having a sequestration ( Fig. 32-5A ). When found, the vessel is ligated and divided with either the vessel sealer, stapler, clips, or ties ( Fig. 32-5B ). The inferior pulmonary vein is identified but not ligated at this point. Ligation of the vein before division of the pulmonary artery can lead to congestion in the lower lobe, which can then create space issues and poor visualization, especially in the smaller child and infant.
After division of the inferior pulmonary ligament, the fissure is approached. If the fissure is incomplete, the vessel sealer or stapler can be used to complete it. However, care must be taken to ensure that the pulmonary artery is not inadvertently injured at this point. Gradually, moving anterior to posterior within the fissure, the pulmonary artery to the lower lobe is isolated. Depending on the size of the patient and any anatomic variation, the lower lobe artery may present as a single main trunk or at the segmental level. Often, it is necessary to dissect into the parenchyma of the lower lobe to gain adequate exposure and length of the segmental vessels to allow for safe ligation ( Fig. 32-6A ). If possible, the artery is ligated at its main trunk. In the majority of cases, the superior segmental vessel is isolated, sealed, and divided first, thereby elongating the main artery before it branches into the basal segments ( Fig. 32-6B ). The safest technique is to seal the vessel proximally and distally with a space of 3 to 4 mm between the seals. The vessel is then partially cut between the seals with scissors until the lumen is seen. If there is no evidence of bleeding, it means the seals are secure and the vessel can be safely cut. If there is any evidence of bleeding, the vessel sealer can be reapplied, or clips or sutures can be placed before vascular control of the vessel is lost. Any device that seals and divides the vessel simultaneously runs the risk of causing uncontrolled bleeding once the vessel is divided and retracts. The artery can be ligated and divided with the vessel sealer in infants and small children or with the 5- or 12-mm stapler in older children if the vessel is large.