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1 Introduction

Video-assisted and thoracoscopic major pulmonary resections are gaining popularity, as it becomes more and more evident that minimally invasive surgery is beneficial in terms of reduced postoperative pain, shorter hospital stay, shorter recovery, and better compliance to adjuvant chemotherapy, without compromising oncological principles. The number of publications about video-assisted and thoracoscopic lobectomies is rising [1–5], although these procedures are still considered as technically difficult and their learning curve is steep. This observation is even more valid for anatomic segmentectomies that are complex and encompassing a higher rate of postoperative complications. Very few series of video-assisted pulmonary segmentectomies have been published [6–9] and totally endoscopic – so-called complete VATS – segmentectomies are even more rare [10, 11]. Many different techniques of thoracoscopic major pulmonary resection have been described, depending on the use or nonuse of an accessory mini-thoracotomy and on the use or nonuse of endoscopic instrumentation and video display. One of these techniques is the totally endoscopic approach, in which only endoscopic instruments and monitor control are used. This is the technique that will be described in this chapter. By totally endoscopic, we mean (1) 100% video display, (2) no access incision, and (3) only use of trocars and endoscopic instruments. The aim of this chapter is not to discuss the oncologic validity of segmentectomies for early-stage lung carcinomas – their benefits have been recently underlined [6, 12, 13] – but to describe the technical aspects of totally endoscopic anatomic segmentectomies (TEAS) and their results.

2 General Considerations About Endoscopic Segmentectomies

As mentioned by Oizumi et al., thoracoscopic segmentectomy poses some unique challenge to surgeons because – even when done via thoracotomy – the procedure is reputed being complex [10]. Not only the anatomical relationships can be difficult to grasp, especially for the young and less experienced surgeons, but the identification and division of the intersegmental plane is a real concern. Because of the endoscopic vision with its magnification and unusual viewpoints, the anatomical landmarks are changed. In addition, restricted tissue manipulation and use of endoscopic instruments are disturbing.

2.1 Ergonomics and Operating Room Setting

It is usually admitted than video-assisted surgery should be done with triangulation of the endoscope and instruments which are positioned opposite one another. This rule is almost impossible to follow during endoscopic major pulmonary resections for the following reasons:

These procedures are lasting 2–4 h. Maintaining an awkward position with both arms spread apart is exhausting and can provoke shoulder pain and stiffness.

In these complex operations, there is not just one but several targets (pulmonary hilum, mediastinum, diaphragm etc.) so that there is not a single ideal position of the scope and instruments. Therefore, whenever possible, we have found it more comfortable manipulating the two working instruments from the back or from the front, depending on the resection to be performed. The opposite side is used for insertion of a lung retractor or a suction device.

The scope is held by a robotic or mechanical scope holder, according to the surgeon preference. Its position should be shrewdly chosen so that it does not conflict with instruments. Endoscopic instruments and trocars are placed on a dedicated rack, and the conventional thoracic instruments are prepared on a separate table.

2.2 Trocars

What is the position of trocars is a frequently asked question. Unfortunately, there is no fixed and definite position. It depends not only on the type of resection but also on the patient’s morphological type and on the surgeon’s habits and preferences. For instance, we prefer performing left resections with the instruments coming from the front, while for right-sided resections, we use a dissection from the back (Figs. 10.1 and 10.2). Other surgeons may feel more comfortable with another approach and different positioning. The only rule we would recommend is inserting the scope in the midaxillary line, in the 6th or 7th intercostal space, depending on the patient’s morphological type, because of the need to have an overall view on the whole pleural cavity. Many tasks can be done with micro-instruments. This avoids large ports and, consequently, large scars.

Fig. 10.1
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Schematic illustration of port sites during an apical segmentectomy of the left lower lobe

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Fig. 10.2
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Schematic illustration of port sites during an apicoposterior segmentectomy of the right upper lobe

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2.3 Enhancing Vision and Video Imaging

During open surgery or VATS, the surgeon usually stands at the patient’s back because the anatomical landmarks are more familiar to him/her that way. It is sometimes preferable to stand at the patient’s front [3], or to switch from behind to the front, according to the operation steps. This means that at least two monitors should be used. The light in the operating room should be reduced as much as possible to enhance the monitors contrast. As working many hours in the dark is tiresome for the staff, the best compromise is to have a blue background lighting which offers a nice contrast and does not oblige working in the dark.

Since the procedure is long lasting, the endoscope tip may be soiled by blood drops sliding down along the trocar sheath [14]. This annoying issue can be partly overcome by using a 12-mm trocar instead of a 10 mm. The port is cleaned with a cotton-tipped applicator. Smoke aspiration can be achieved via a 3-mm suction device that is left in place throughout the procedure.

Maintaining optimal vision of the whole operative field with a single 0° optic is almost impossible. One of the main concerns with a direct viewing scope (0°) is the difficulty in controlling the instrument tip which may be out of the field of vision. Formerly, to overcome this problem, we switched from a direct (0°) to an oblique viewing endoscope (30°) as vision became too tangential. However, these maneuvers were time consuming and tedious. The rigid scope with a deflectable tip (Olympus LTF™, Tokyo, Japan) has an angle of vision that varies from 0° to 100° (Fig. 10.3). The flexibility is controlled by a lever located on the handle. Once chosen, the angulation can be locked. This allows the surgeon to have a bird’s-eye view, making dissection more natural and safer. The endoscope tip houses a distal CCD connected to a high definition television standard (HDTV) camera (Exera II™, Olympus) which provides dramatically sharp viewing, thus allowing for close-up vascular dissections [15].

Fig. 10.3
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High definition deflectable tip thoracoscope (Olympus LTF™) allows performing the whole procedure with a single endoscope avoids the problems related to tangential vision. Its angle of vision that varies from 0° to 100°

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2.4 Obtaining a Pathological Diagnosis

Patients who are selected for a totally endoscopic segmentectomy usually present with a clinical stage I tumor. This means the tumor or nodule is often small and not accessible to a preoperative CT-guided biopsy. Thus, many patients are operated on without confirmed pathological diagnosis. When the nodule is small and subpleural, the easiest way is to perform a wedge resection with frozen section. In other cases, we use a biopsy needle (Bard Monopty®, Covington GA) which provides a pathological diagnosis in most cases (Fig. 10.4).

Fig. 10.4
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Intraoperative view of a needle biopsy

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2.5 Exposure and Lung Retraction

The most efficient and most natural way to retract the lung is by mean of a 5- or 10-mm forceps. However, though it is sometimes necessary, the use of a forceps has two drawbacks: (1) it requires an additional port, and (2) it frequently tears the parenchyma, causing oozing or even hemorrhage. Although these minor bleedings are seldom serious, these may be very troublesome. Some have proposed to retract the lung with an endo-loop [16]. When there is no need to retract the lung with force, pushing it back with a simple endoscopic peanut is as effective while being less traumatic.

For long lasting steps where the lung needs to remain retracted, we use either a 3-mm grasping forceps or a miniaturized lung forceps that can be released inside the chest cavity (Aesculap©) [17] (Fig. 10.5). It has a triangular tip, as most lung forceps. A 30-cm-long thread is passed and secured at its ring-shaped basis. Once applied on the portion of the lung to be retracted, the thread is loaded through a 2-mm fascial closure device – whose primary use is port site closure during laparoscopy – and simply passed through the skin. Tension is then adapted by pulling the thread more or less. If needed, two retractors can be used.

Fig. 10.5
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Lung retraction: use of mini-retractors that can be released inside the chest cavity and pulled through the chest wall by a thread

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2.6 Fissures

The access to the branches of the pulmonary artery is easy or difficult depending on whether the fissure is separated or fused. Opening a largely fused fissure may be a tedious step of the procedure. The main concern is that opening and dissecting the fissure can cause some minor oozing that is troublesome during a thoracoscopic operation where the operative field must remain as dry as possible to maintain optimal vision. One of the keys of a bloodless dissection is to progress step by step, from the periphery to the hilum. We have found thin instruments such as ultrasonic (SonoSurg™, Olympus) or electrothermal bipolar shears (LigaSure™, Valleylab) to be less cumbersome and as effective as stapler for the division of the external part of the fissure. For the inner thick part of the fissure, stapling is however required. A guide is usually necessary to drive the stapler jaws without excessive friction and force on the tissue. We use a small diameter silicone suction tube whose base is connected to the stapler tip, or we retract the fissure with a tape.

With a direct viewing telescope, the division of the fissure can be difficult because its length may make sharp vision on both of its extremities, almost impossible. A deflectable tip thoracoscope is of great help during this step because it allows a bird’s-eye view of the whole fissure throughout the dissection.

In case of fused fissures, identifying some branches of the pulmonary artery (PA) is tedious. This is usually not an issue for lower segmentectomies but can be a real concern for upper segmentectomies since the branching pattern exhibits many variations, especially on the left side. Therefore, preoperative knowledge of vascular anatomy can be helpful. Three-dimensional reconstruction with volume-rendering technique provides an accurate vascular mapping of the lobe or segment to be dissected. This preoperative investigation is time consuming but does not have additional cost or invasiveness since a preoperative CT with injecting contrast medium is needed anyway.

2.7 Exposure of Bronchial and Vascular Elements

2.7.1 Anatomical Issues

The understanding of anatomy and of the branching pattern of the pulmonary artery can be difficult, since it is highly variable, especially for upper lobes. For lower lobes, anatomical ­variations do not pose problem and the surgeon can rather easily adjust to an unusual vascular anatomy. For instance, even when there are variations on the vascular pattern of the apical segment of the lower lobe, there is usually no doubt about the distributions of arterial branches (Fig. 10.6). Figure 10.7 shows three different arterial distributions to the left basilar segments, as seen on three-dimensional volume-rendering imaging and on the corresponding thoracoscopic view (Fig. 10.7). These views demonstrate that the anatomy is easily understandable and that the respective branches can be selected according to the segmentectomy performed. Thus, we do not perform anymore a preoperative reconstruction of vessels for lower segmentectomies. However, the issue is more relevant for upper segmentectomies. Not only, the number of arteries arising from the pulmonary artery is variable but their distribution is sometimes difficult to understand because the vessels can usually not been dissected on a sufficient length. This is especially true for the ascending arteries to the right upper lobe. These arteries can supply only the posterior segment of the upper lobe or both the posterior and anterior segments (Fig. 10.8). The study of preoperative computed tomography three-dimensional reconstruction helps asserting the number, size, and direction of these arteries without doubt. For example, knowing preoperatively if the left truncus anterior gives an accessory lingular artery is helpful when embarking in a lingula sparing upper lobectomy (Fig. 10.9). Thus, in our experience, a preoperative assessment of the vessels remains useful for upper segmentectomies. Assessing preoperatively the arterial variations and having the vascular pattern in mind help the surgeon performs a safer dissection of the branches of the pulmonary artery, especially when the fissure is fused and/or when lymph nodes are present. In a series of 49 patients selected for VATS lobectomy, Watanabe et al. found that preoperative three-dimensional computed pulmonary angiography was identifying the PA branches in 95% of the cases [18]. In their series, only some small branches (less than 2 mm in diameter) were missed.

Fig. 10.6
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Example of three different arterial supplies to the basilar segment of the left lower lobe, as seen during thoracoscopic left apical segmentectomy. The distribution of the arteries to the apical segment is clear. (a) Single apical segmental artery, (b) double apical segmental artery, (c) triple apical segmental artery. LUL left upper lobe, LLL left lower lobe

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Fig. 10.7
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Example of three different arterial supplies to the apical segment of the left lower lobe, as seen during thoracoscopic left basilar segmentectomy. Note the exact correspondence between the computed tomography three-dimensional reconstruction and the thoracoscopic view. (a) Single basilar trunk, (b) early division of the basilar trunk in two main arterial trunks, (c) early division of the basilar trunk in four arteries. LUL left upper lobe, LLL left lower lobe

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Fig. 10.8
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Thoracoscopic view of two ascending arterial branches in the fissure during a right apicoposterior segmentectomy (a). Note that the computed tomography three-dimensional reconstruction helps asserting that the smallest artery (arrow) supplies the anterior segment (b). RUL right upper lobe, RLL right lower lobe, PA posterior artery, AA anterior artery, ISV intersegmental vein

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Fig. 10.9
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(a) Computed tomography three-dimensional reconstruction of the left pulmonary artery demonstrating an independent apicoposterior and accessory lingular artery, (b) corresponding thoracoscopic view after completion of a lingula sparing upper lobectomy

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2.7.2 Bronchial and Vascular Control

Exposing and retracting a bronchus or a vessel are frequently necessary when it needs to be loaded within the jaws of a clip applier or an endostapler. The latter must be passed as smoothly as possible. One can use some deflectable devices (Endo MiniRetract™, Covidien or Goldfinger™, Ethicon whose tip has the advantage of being atraumatic and has a keyhole for a sling) (Fig. 10.10). These instruments can be used both for retraction and for some blunt dissection to create space around the element to be stapled. If this is not sufficient, a guide can be used. We use a chest tube or a 16 Fr suction tube (Gentle-Flow™, Kendall©). Its base is secured to the anvil by simple pressure. This can be done inside or outside the chest. Its distal end is passed around the structure to be divided and pulled out through the trocar tube. The stapler tip is thus guided around the tissue to be stapled.

Fig. 10.10
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Example of dissection and retraction of the basilar segmental vein using a deflectable retractor during a left basal segmentectomy

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Whenever possible, clips should be avoided because they may slip or conflict with staples. However, medium diameter vessels such as some segmental pulmonary branches are too small for an endostapler and too large to be coagulated with electrocautery or ultrasounds. When clips are used, they are doubled or even tripled. Another solution is to apply a clip at the origin of the vessel and complete division with bipolar sealing, so that only one clip is present in the operative field. For all other minor vessels, we use ultrasonic shears (US) (EndoSurg™, Olympus) or a bipolar vessel sealing device (VSD) (Ligasure™, Covidien). Large vessels are stapled. Complications related to stapling of bronchus or parenchyma are rare but have been reported while accidents with vascular stapling are extremely rare [19]. However, the stapler must load the vessel without any force or friction, which implies a perfect vascular dissection. Lymphadenectomy is done only with VSD, and clips are almost never used. A suction device can be activated all over the dissection time for immediate evacuation of smoke and mist.

2.7.3 Vascular Injuries

Avoiding bleeding and massive vascular injury is a constant concern throughout the procedure. Some authors have advocated clamping the main pulmonary artery using a silk suture in order to control any bleeding [20]. This maneuver can be easily achieved during conventional open procedure or even during some VATS procedures through a utility mini-thoracotomy. But it seems at risk to be done via a totally endoscopic approach, because a tear of the main pulmonary artery could not be controlled. This is one of the limitations of the endoscopic approach. However, in patients presenting with a regular anatomy, the risk of major vascular injury is minimal due to the close-up dissection and the camera magnification. Dissection becomes more risky when neoplastic or inflammatory lymph nodes are present and prevent opening the vascular sheath which is adherent to the underlying vessel. These situations should lead to abandon and convert to an open procedure.

Massive Hemorrhage: Although it never occurred in our experience, a massive bleeding that is not controllable by thoracoscopy should lead to introduce gauzes through the larger port and temporary control bleeding by pressure, while the surgeon convert to thoracotomy. This outlines the importance of having the conventional thoracic instruments ready on a separate operative table.

Minor Hemorrhage: A 5-mm clamp must be available. An alternate solution is the use of throw-off vascular bulldog clips (Aesculap©). They are used for controlling a hemorrhage or during the temporary occlusion of a vessel. They are inserted through a 12-mm trocar using a dedicated applier that is withdrawn after the device has been applied. The same instrument is used for retrieving the device.

2.8 Intersegmental Plane and Division of the Parenchyma

Another difficulty faced during thoracoscopic segmentectomy is the identification and division of the intersegmental plane. When performed through a thoracotomy, this step is facilitated by the use of manual inspection and palpation which are not possible via thoracoscopy. Several methods have been described. The most common is the creation of a ventilated-deflated line by reventilating the operated lung once the segmental bronchus has been stapled. This technique has two drawbacks: (1) reventilation obscures the vision, a much more troublesome problem than during thoracotomy; (2) the segments to be resected can be partly reventilated through the collateral canals, leading to an unclear demarcation line. Therefore, some authors have suggested acting reverse, i.e., reventilating the whole lung once the segmental bronchus has been divided and then collapsing it, so that only the diseased segments remain inflated [18]. Others have suggested using selected jet ventilation in the segmental bronchi to be divided [8]. We have used a similar method by injecting air through the channel of a bronchofiberscope, after selective endoscopy of the segmental bronchus. In our experience, the technique resulted in some inflation of adjacent segments and was eventually disappointing.

Once the intersegmental plane has been determined, the last issue is the choice of the division method. Some authors use a combination of blunt dissection, electrocautery, and application of fibrin sealant [8] (Table 10.1). When air leaks are observed, some surgeons applied mattress suture with pledgets [18]. These methods have the advantage of sparing parenchyma but comprise a risk of postoperative air leak. Actually, most authors use staplers [6, 9, 21, 22] (Table 10.1). Stapling is however not that easy. First, it may require using many cartridges, up to five in the series of Watanabe [18]. Second, the limited opening of the endostaplers and the thickness of the parenchyma expose to disruption of the staples line [23], an adverse event that occurred twice in our series. The consequences are not serious but lead to troublesome blood loss and require suturing.

Table 10.1 Technical data available for published series of VATS or totally endoscopic segmentectomies
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2.9 Specimen Retrieval

It would not be recommended to morcellate the specimen as done in other fields of surgery, since it is of utmost importance to analyze the bronchus, the peribronchial lymph nodes, and to check that all margins are free. The segment must be retrieved en bloc. For a segmentectomy, enlarging a port on a 2–3 cm length is sufficient. The use of a retractor is never necessary. A solid and large specimen bag must be used. The incision should be done at a site where the intercostal space is soft, preferably in the lower part of the chest on the anterior axillary line or in the axilla.

3 Technique

Only the right apicoposterior segmentectomy will be described in details and illustrated as many technical principles can be applied to other resections. A detailed description of all types of anatomic segmentectomy has been given in another work [24].

3.1 Right Upper Lobe: Apicoposterior Segments

The right upper lobe comprises three segments: apical (S1), posterior (S2), and anterior (S3). The three segmentectomies of the right upper lobe are feasible. With respect to the anterior segment, dissection is considered as one of the most challenging for the following reasons: the segmental bronchus is not easily accessible, the anterior segmental artery is covered by the apical vein, and the preservation of the anterior segmental vein is tedious. For these reasons, only the apicoposterior segmentectomy will be described thereafter. As mentioned above, this is one of the procedures where the surgeon takes profit of a preoperative three-dimensional reconstruction of the vascular anatomy (Fig. 10.11).

Fig. 10.11
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Vascular landmarks as demonstrated by three-dimensional reconstruction: (a) arterial supply to the apicoposterior segments (anterior view), (b) relationships between veins and arteries of the apicoposterior segments (anterior view) (dotted lines level of division, a artery, v vein)

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3.1.1 Fissure and Ascending Posterior Artery

As for some right upper lobectomies, it is more convenient to start the resection by controlling and dividing the bronchi. However, this can be done only if the ascending posterior artery, which hides the upper lobe bronchus, is severed. The posterior aspect of the oblique fissure is opened. This is achieved by stretching the upper lobe or lower lobe anteriorly, until the posterior mediastinum is fully exposed. The pleura facing the inferior aspect of the upper bronchus is opened using either cautery or blunt dissection or both. A dissecting forceps is then passed from the hilum – at the level of the posterior aspect of the pulmonary artery – to the periphery under vision control, thanks to the deflectable scope. A 60-mm endostapler can then be applied. This helps expose the posterior artery (Fig. 10.12a) which is then dissected and clipped or severed after bipolar sealing. Dissection of this artery can be tedious if multiple venous branches run within the fissure (Fig. 10.12b).

Fig. 10.12
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Exposure of the ascending artery to the posterior segment after division of the posterior part of the oblique fissure. (a) On a patient without venous branches in the fissure, (b) on a patient with venous branches crossing the posterior ascending artery. RUL right upper lobe, RLL right lower lobe

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3.1.2 Segmental Bronchi

Once the ascending posterior arterial branch has been divided, the anterior surface of the right upper bronchus is fully exposed. The tissues overlying its superior aspect are freed using a cautery hook. Clearing of the upper lobe bronchus must be pursued forward until the apical segmental bronchus becomes apparent.

Dissection of the segmental bronchi is continued by a combination of gentle traction of the upper lobe and blunt dissection. This is best achieved by an Endo Peanut while any oozing or minor bleeding from small peribronchial arteries is immediately controlled. Finally, the trifurcation is exposed: the anterior segmental bronchus which is the lowest branch and the posterior and apical bronchi which can take off independently or as a common stem (Fig. 10.13).

Fig. 10.13
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Exposure of the segmental bronchi of the right upper lobe. (a) Independent bronchi, (b) common apicoposterior stem

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At this stage, two different situations can be faced: (1) dissection is easy because tissues are soft and anatomy is clear, and (2) dissection is uneasy. In the later situation, getting around the bronchi is at risk of tearing the arteries which run anterior to the bronchi. One should prefer controlling the truncus anterior and the apical artery from the mediastinal side. But if the dissection is smooth, turning around the apical and posterior bronchi from the back is possible, always keeping in mind that the arteries run anteriorly to the bronchi. A blunt tip retractor is used to retract the bronchi backward and move them away from the arteries (Fig. 10.14). The bronchi can then be stapled one by one or as a stem.

Fig. 10.14
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Retraction of the apicoposterior bronchus

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3.1.3 Apical Artery

This maneuver liberates the apicoposterior segments which unfold forward, thus exposing the apical artery, which is the uppermost tributary of the truncus anterior. Dissection of its posterior and lateral aspects can be done from behind. If necessary, its anterior aspect can be freed from the front after exposure of the truncus anterior by retracting the upper lobe backward (Fig. 10.15). The apical artery is stapled.

Fig. 10.15
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Exposure of the apical artery. (a) From the back by retracting the upper lobe forward, (b) from the front by retracting the upper lobe backward

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3.1.4 Apical Vein

The superior pulmonary vein is exposed by retracting the upper lobe backward and incising the mediastinal pleura posterior to the phrenic nerve (Fig. 10.16a). Its dissection is achieved by a combination of bipolar cautery and gentle sweeping motion with an Endo Peanut. The three segmental branches of the upper root of the superior pulmonary vein are exposed as well as the origin of the middle lobe vein. Theoretically, both the apical and posterior venous branches should be divided. However, even if the segmental pattern of the vein is clear, it seems advisable to divide only its uppermost tributary (Fig. 10.16b), since one cannot be certain that the branch in the middle of the trifurcation does only drain the posterior segment.

Fig. 10.16
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Dissection of the superior branch of the superior pulmonary vein. (a) Approach to the superior pulmonary vein using bipolar diathermy, (b) dissection of the superior branch

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3.1.5 Division of the Parenchyma

Once all segmental vascular and bronchial elements have been divided, the lobe can be lifted up and a clamp is applied on the parenchyma (Fig. 10.17a). Low volume and low pressure reventilation help determine the intersegmental plane while the clamp is repositioned on the demarcation line between ventilated and ­non-ventilated zones. Some force is applied on the clamp to crush and flatten the parenchyma. The 60-mm endostapler with 4.8-mm cartridge can then be applied (Fig. 10.17b). The specimen is placed into an endobag and retrieved after minor enlargement of a port. The pulmonary ligament is freed to facilitate reexpansion, a chest tube is placed, and the lung is reventilated (Fig. 10.18).

Fig. 10.17
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Division of the parenchyma. (a) Delineation of the intersegmental plane by clamping, (b) stapling. The bronchial stump (white arrow) must be kept remote of the stapler jaws

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Fig. 10.18
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Final view before reventilation. (a) Close-up view of the bronchial trifurcation, (b) final aspect after specimen retrieval and reventilation

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3.2 Right Lower Lobe: Superior Segment

Resection of the superior segment (S6) of the right lower lobe is reasonably easy, thanks to the constant anatomical landmarks. However, as for a right lower lobectomy, the exposure of the pulmonary artery and its segmental branch can be tedious in case of fused fissure.

3.2.1 Fissure and Artery

This step is similar to the dissection of the fissure during a right lower lobectomy. The pulmonary artery may be visible or hidden if the fissure is fused. Depending on the difficulty in identifying the arterial pattern, it can be advisable to first open the posterior part of the fissure or, on the contrary, to first dissect the pulmonary artery.

The posterior fissure is opened, as for a right lower lobectomy. Once the pulmonary artery has been identified, a dissecting forceps is introduced from the posterior surface of the artery toward the posterior mediastinum. This may require retracting the lobes forward in order to expose the posterior mediastinal pleura. The pleura is incised at the level of the intermediate bronchus. An oblique viewing endoscope or a deflectable scope is helpful to control this maneuver. The posterior fissure is then stapled.

The pulmonary artery is dissected in the fissure. It is not necessary to expose the whole arterial crossroad, but the origin of the posterior ascending branch to the upper lobe and the origin of the basal trunk should at least been made out, making sure that no accessory branch originates from the superior artery. The superior segmental artery, which runs anteriorly to the segmental bronchus, is usually single. It is dissected, clipped, or stapled, depending on its size.

3.2.2 Bronchus

The division of the segmental artery gives access to the segmental bronchus which is cleared of peribronchial tissues and stapled.

3.2.3 Vein

The pulmonary ligament is incised up to the lower vein using both diathermy and gentle traction on the lower lobe. The inferior vein is cleared from the surrounding tissues, until its uppermost tributary is identified. It lies usually inferior to the bronchus. It can be clipped or divided after application of bipolar sealing.

3.3 Right Lower Lobe: Basal Segments

In addition to the superior segment (S6), the lower lobe comprises four basal segments: medial (S7), anterior (S8), lateral (S9), and posterior (S10). These segments are usually removed together since they depend from a single bronchial trunk. The main steps of the procedure are similar to those of a right lower lobectomy. The main concern is the preservation of the elements of the superior segment, especially the superior segmental vein.

3.3.1 Fissure and Artery

The dissection starts as for a lower lobectomy. The pulmonary artery is identified at the junction of the oblique and transverse fissure. When the fissure is incomplete or inflammatory, this step can be tedious. Opening the fissure can lead to pulmonary tears and troublesome oozing. Thorough progression using a combination of bipolar diathermy and blunt dissection is required until the artery is discovered. There is no need to divide the posterior portion of the oblique fissure. Access to the basal trunk is facilitated by the division of the anterior portion of the oblique fissure between the middle lobe and lower lobe. This part of the fissure is usually thin and can be split by bipolar or ultrasonic dissection. If its central portion is too thick, stapling can be necessary.

The sheath of the artery is entered. The artery to the middle lobe and the posterior segmental artery to the upper lobe must be clearly visible before any division. The basal trunk can then be stapled.

3.3.2 Bronchus

Division of the basilar trunk gives access to the basal bronchus which is cleared and divided, with avoidance of impingement on the segmental superior bronchus. If any doubt, a reventilation test can be helpful.

3.3.3 Vein

The pulmonary ligament is incised up to the lower vein using both diathermy and gentle traction on the lower lobe. The inferior pulmonary vein is cleared from the surrounding tissues, and its basal branches are dissected. They can join the inferior pulmonary vein, either via multiple segmental branches or via two trunks. Demonstration of the segmental veins is achieved by using a combination of gentle traction of the lobe and blunt dissection with an Endo Peanut. All branches are isolated and clipped, taking care to preserve the superior segmental vein.

3.3.4 Division of the Parenchyma

A long clamp is applied on the parenchyma. A reventilation test allows delineating the intersegmental plane. The parenchyma is compressed by the clamp to ease stapler application.

During stapling, the bronchial and arterial stumps should be pushed away so that they stay on the specimen side and remote from the stapler jaws. A constant watch should be kept on the superior segmental vein.

3.4 Left Upper Lobe: Superior Segments

Segmental resections involving the left upper lobe are the following: upper division (S1  +  2 and S3) (lingular sparing lobectomy), apicoposterior segmentectomy (S1  +  2), and lingulectomy (S4 and S5).

3.4.1 Upper Division

The procedure is similar to a left upper lobectomy apart from the lingular vessels which are preserved and the anterior portion of the fissure which does not require splitting. As for an upper lobectomy, part of the dissection can be carried out from behind.

3.4.1.1 Veins

The superior branches of the superior pulmonary vein partly hide the truncus anterior and should be divided first. The upper lobe is pulled backward. The mediastinal pleura is incised posterior to the phrenic nerve. Dissection of the vein is achieved by a combination of bipolar diathermy and gentle sweeping motion with an Endo Peanut. The lowermost tributary which drains the lingula is preserved. Only the two superior branches are divided using either a stapler or clips or a vessel sealing device, depending on their diameter.

3.4.1.2 Truncus Anterior

Division of the veins gives access to the anterior surface of apicoposterior and anterior branches of the truncus anterior. Clearing of their posterior and superior surfaces require a posterior dissection which is achieved by retracting the upper lobe downward and forward. The apicoposterior and anterior branches are stapled.

3.4.1.3 Fissure and Posterior Arteries

Both lobes are spread apart to expose the middle portion of the fissure. The upper lobe is gently pulled forward, avoiding any undue traction which could lead to injury to the vessels. Dissection is conducted cephalad, and all encountered posterior arteries are divided by turn. Traction helps expose the first segmental artery whose dissection is usually easy. It is controlled by clipping or with a vessel sealing device or with a combination of both.

As the posterior segmental arteries are gradually divided, the upper lobe unfolds and uncovers the posterior aspect of the truncus anterior which can be approached posteriorly. It is then also dissected from above and from the front, using various visions, thanks to the deflectable scope. Gentle blunt dissection is used to clear the origin of the trunk. If the trunk bifurcates into two large branches, these are dissected with caution and stapled independently.

3.4.1.4 Bronchi

Once the arteries and veins have been divided, traction on the parenchyma helps expose the segmental bronchi. The origin of the lingular bronchus is visualized, and the upper trunk – which separates into an anterior bronchus and an apicoposterior bronchus – is exposed, cleared using a blunt tip dissector, and stapled as a stem.

3.4.2 Apicoposterior Segmentectomy

From the vascular aspect, the procedure is simpler since only the apical and posterior arteries are divided, and this can be done from behind by stretching the upper lobe anteriorly. But, from the bronchial aspect, the dissection of the segmental bifurcation can be difficult, especially in case of peribronchial nodes, because of the shortness of the segmental bronchi.

3.4.2.1 Fissure and Arteries

This step is similar to the posterior control of arteries during a lingular sparing upper lobectomy. The only difference is that only the uppermost branch of the truncus anterior requires division. This can be achieved through a total posterior approach or partially through an anterior dissection of the hilum for the control of the apical artery.

3.4.2.2 Vein

When the superior pulmonary vein receives multiples radiating branches, making the venous pattern difficult to grasp, only the uppermost vein should be divided, thus making sure to preserve the middle branch which drains the anterior segment.

3.4.2.3 Bronchi

As above mentioned, the segmental bronchi are concealed by arteries which should always be divided before dissection of the segmental bronchi. Once the posterior segmental arteries have been divided, the posterior surface of the bronchi appears. Gentle retraction of the upper lobe and blunt dissection with an Endo Peanut progressively expose the segmental trifurcation: the anterior segmental bronchus (the lowermost and the most anterior one) which will be preserved and the apicoposterior trunk. Although the arteries have already been divided, it is advisable to keep flush with the bronchi as the dissection of their anterior surface is pursued. Since these bronchi are short, a guide for the stapler can be helpful.

3.5 Left Upper Lobe: Lingula

Although a lingulectomy (S4 and S5) is equivalent to a middle lobectomy with respect to pulmonary function and anatomy, it is actually technically more difficult because of the variable anatomical relationships.

3.5.1 Fissure and Artery

The anterior portion of the oblique fissure is open from the periphery to the hilum. The peripheral portion is usually thin so that the division can be initiated with either ultrasonic shears or a bipolar sealing device. When the fissure is thick and large, it is preferable to first staple its peripheral portion, always keeping an eye on the pulmonary artery.

The anterior aspect of the pulmonary artery is approached, and its sheath is opened. The lingular artery – its trunk or the two segmental branches – is divided after clipping or stapling, depending on its diameter.

3.5.2 Bronchus

The division of the lingular artery allows identification of the upper lobe bronchus and the lingular bronchus which is its lowest and most anterior branch. It is dissected, taking care to the artery of the anterior segment which runs behind the bronchus. The lingular bronchus has a short course and the peribronchial space is very narrow so that a guide can be helpful for passing the stapler anvil smoothly.

3.5.3 Vein

The lowest tributary of the superior pulmonary vein is transected. It can be difficult asserting that the adjacent venous branch drains the lingula. When in doubt, this branch must not be divided until the lingula has been fully mobilized, and the intersegmental plane has been initiated.

3.6 Left Lower Lobe: Superior Segment

Resection of the superior segment (S6) of the left lower lobe is more or less similar to the resection of the superior segment of the right lower lobe but even simpler because the segmental artery is usually readily identified in the fissure.

3.6.1 Fissure and Artery

This step is similar to the dissection of the fissure during a left lower lobectomy. The posterior fissure is opened by inserting the tip of a dissecting forceps from the posterior aspect of the pulmonary artery to the posterior mediastinum. This may require retracting the lobes forward in order to expose the posterior mediastinal pleura. An oblique viewing endoscope or a deflectable scope is helpful to control this maneuver. The posterior fissure is then stapled. The superior segmental artery, which runs anteriorly to the segmental bronchus, is usually single, sometimes double. It is dissected and clipped.

3.6.2 Bronchus

Division of the segmental artery gives access to the segmental bronchus which is cleared and divided, with avoidance of impingement on the basilar bronchus. If any doubt, a reventilation test can be helpful.

3.6.3 Vein

The pulmonary ligament is incised up to the lower vein using both diathermy and gentle traction on the lower lobe. The inferior vein is cleared from the surrounding tissues, until its uppermost tributary is identified. It lies usually inferior to the bronchus. It can be clipped or divided with a vessel sealing device.

3.7 Left Lower Lobe: Basilar Segments

In addition to the superior segment (S6), the lower lobe comprises four basal segments: anterior (S7), medial (S8), lateral (S9), and posterior (S10). Although the medial and anterior (S7  +  8) and the posterior and lateral (S9  +  10) segments can sometimes be individualized, it is usual to remove all basal segments together. The procedure is similar to a left lower lobectomy. Only the demonstration of the basilar vein and the recognition of the intersegmental plane may be difficult.

3.7.1 Fissure and Artery

The dissection starts as for a lower lobectomy. Once the peripheral portion of the fissure has been divided, it becomes easier to display the reflection of the mediastinal pleura, between the two pulmonary veins. The pleura is opened with electrocautery, and a right angle dissector can then be passed toward the pulmonary artery. This allows completing the division of the anterior fissure.

Completion of the anterior fissure division helps expose the pulmonary artery whose sheath is opened. The basilar trunk is dissected. There is no need to isolate the superior segmental artery, but the latter must be identified before stapling the basilar artery which can present as a common trunk or with multiple branches. The posterior part of the fissure does not need to be stapled.

3.7.2 Bronchus

Division of the basilar trunk gives access to the basal bronchus which is cleared and divided, with avoidance of impingement on the segmental superior bronchus. If any doubt, a reventilation test can be helpful.

3.7.3 Vein

The pulmonary ligament is incised up to the lower vein using both diathermy and gentle traction on the lower lobe. Demonstration of the segmental vein is achieved by using a combination of gentle traction of the lobe and blunt dissection with an Endo Peanut. The vein is cleared from the surrounding tissues, and its inferior root is dissected, isolated, and clipped, with care taken to preserve the superior segmental vein.

4 Experience (Table 10.2)

From January 2008 to June 2011, TEAS was attempted in 71 patients (34 males and 37 females) ranging in age from 25 to 81 years (mean, 56). The indication was either a benign lesion (18 patients), a solitary metastasis (12 patients), or a suspicion of clinical stage I non-small-cell lung carcinoma (NSCLC) (41 patients). For the patients operated on for a suspicion of primary lung carcinoma, the reason for performing a segmentectomy was an impaired lung function and/or a previous history of pulmonary resection (segmentectomy in 1 patient and lobectomy in 2 patients).

Intraoperative and postoperative data were recorded in a prospective manner. The data were the following: need for conversion to open thoracotomy, duration of the surgical procedure as noted on the operating room records, operative blood loss, intraoperative complications, number of collected lymph nodes and of dissected lymph node stations for patients operated on for NSCLC, duration of chest drainage, postoperative stay, and postoperative complications. We did not include in the series the 31 thoracoscopic right middle lobectomies (segments S4 and S5) which were performed in the same period of time, as other authors did [12] basing on the anatomic and functional similarity between the middle lobe and the lingula.

4.1 Technical Aspects

All patients candidate to an upper segmentectomy had a multidetector row preoperative computed tomography (CT) angiography with three-dimensional volume-rendering reconstruction of arterial and venous anatomy [11, 25, 26]. CT reconstruction was not done for the lower segments since anatomical variations of the vascular supply to the lower lobes have less impact on the surgical technique and can be easily managed. A radical lymphadenectomy was performed for all patients operated on for a suspicion of lung carcinoma. No utility incision was used. On completion of the pulmonary resection, the specimen was wrapped into an endobag and retrieved through one of the port sites that was enlarged to a length of 2–4 cm (Fig. 10.1b), depending on the specimen size [11]. The use of a rib spreader was never required for this task. Depending of the type of resection, one or two chest tubes were placed through the port sites. Their removal was decided according to usual rules, i.e., no air leakage and output inferior to 150 cc/day.

4.2 Results

There were three conversions to thoracotomy (4.2%) for a noncontrollable hemorrhage from the apical artery during a right apicoposterior segmentectomy. All three patients had a simple postoperative course and were discharged before the eighth postoperative day. In the 68 other patients who had a totally endoscopic procedure, there were two intraoperative complications, i.e., a partial disruption of the staple line during division of the intersegmental plane. It required endoscopic suturing. The postoperative course of these two patients was simple, and they were discharged at days 4 and 5. The operation time ranged from 92 to 315 min (mean, 181  ±  52 min). The estimated blood loss ranged from 0 (nonmeasurable) to 450 ml (mean, 77  ±  69 ml). No patient needed blood transfusion. All but six patients had an uneventful postoperative course (12%). The complications were minor and were the following: prolonged air leak (>6 days) (2), pneumothorax requiring chest drainage (2), sputum retention requiring bronchoscopy (2), and neurologic disorder (1). The drainage duration ranged from 1 to 7 days (mean: 3.1  ±  1.8 days) and the hospital stay from 2 to 14 days (mean: 5.6  ±  2.4 days). For the 41 patients who were operated on for a suspicion of primary lung carcinoma and who had an additional lymphadenectomy, the mean number of collected lymph nodes from station 10 ranged from 0 to 6 (mean: 3  ±  2) and from station 11 ranged from 1 to 9 (mean: 3  ±  2). The mean number of collected mediastinal lymph nodes was 18  ±  8, and the mean number of dissected lymph node stations was 3.5  ±  1. In lung cancer cases, the tumors were staged pathological N0 in all but two cases which were upstaged N2.

5 Conclusion

Although a totally endoscopic approach to anatomic segmentectomies can seem challenging and difficult, the operation time was reasonable in our series and the morbidity rate was low, as in other recent series (Table 10.3). Experience and improvements of some instruments such as endostaplers will facilitate the procedure. Combining the advantages of an endoscopic approach and an anatomic limited resection could be highly beneficial for those of the patients who fulfill the criteria of a sublobar resection [22].

Table 10.2 Resected segments
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Table 10.3 Results for published series of VATS or totally endoscopic segmentectomies
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