Wedge resection in peripheral lung cancer is considered a suboptimal procedure. However, in elderly and/or frail patients it is a reliable and safer alternative. This procedure can be easily performed under nonintubated anesthesia, allowing the recruitment of patients considered otherwise marginal for a surgical treatment. Nonintubated anesthesia can reduce lung trauma, operative time, postoperative morbidity, hospital stay, and global expenses. Furthermore, nonintubated anesthesia produces less immunologic impairment and this may affect postoperative oncological long-term results. Wedge lung resection through nonintubated anesthesia can be performed for diagnosis with higher effectiveness given the similar invasiveness of computed tomography–guided biopsy.
Key points
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Wedge resection in lung cancer is considered a suboptimal procedure, but in elderly and/or frail patients is a reliable and safer alternative.
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Nonintubated thoracic surgery may allow reduction of operative time, postoperative morbidity, hospital stay, and global economical expenses.
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Nonintubated modality can allow the recruitment of patients considered otherwise marginal for a surgical treatment.
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The nonintubated video-assisted thoracic surgery approach is less traumatic, with less immunologic impairment, which may affect postoperative oncological long-term results.
Introduction
Since the beginning of the nonintubated program, the resection of peripheral undetermined pulmonary nodules was generally believed to be among the main indications for procedures under this kind of anesthesia. Within this group of operations, surgeons have also resected a significant number of lesions that resulted from primitive early and peripheral lung cancer. Unfortunately, limited resection of lung cancer is still considered suboptimal from the oncological point of view and this argument has considerably restricted the indications for nonintubated surgery of lung cancer. Conversely, this anesthetic modality extended the indications for surgery to even the most fragile and oldest patients. Thus, this type of surgery has grown in the space allowed between these 2 extremes: questionable radicality and great tolerability. This article describes the various nonintubated video-assisted thoracic surgery (VATS) techniques for resection of peripheral lung cancer and tries to individuate the main indications for this kind of surgery that, in the authors’ opinions, deserves a particular and precise space in the armamentarium of a thoracic surgeon.
Anesthesia
At first, surgeons performed procedures under thoracic epidural anesthesia (TEA), which could simultaneously cover 3 or 4 metameric regions and allowed a triportal access.
TEA is usually established at the thoracic nerve–4 level by the insertion of an epidural catheter to maintain a continuous infusion of 1.66 μg/mL sufentanil and 0.5% ropivacaine. If the somatosensory block is insufficient, a supplement of 7.5% ropivacaine and 2% bupivacaine can be added at incision sites. Atropine (0.01 mg/kg) or 5 mL of aerosolized 2% lidocaine can be used to reduce the cough reflex. However, these drugs are more likely to be superfluous because the peripheral maneuvering of the lung parenchyma does not produce high stimulation to the vagus nerve.
The reduction of surgical incisions allowed the shift from TEA to local anesthesia. To obtain an adequate analgesia, we separately inject lidocaine 2% (4 mg/kg) at the site of incision and up to the parietal pleura, and 7.5% ropivacaine (2 mg/kg) along the competent intercostal nerve ( Fig. 1 ).
Meanwhile, anesthesiologists refined protocols and techniques, taking advantage of the newest technology, such as bispectral index (BIS) monitoring and vagal blockade. In particular, the introduction of BIS allowed a better control of drug delivery during procedure. Anesthesia can be conducted by keeping the BIS index around 90 to 100, or with a light to moderate sedation (60–90) for patients who are more anxious.
Finally, it must be remembered that these patients are usually sensitive about the impact of the diagnosis on their lives, and this feeling may considerably increase during the procedure. For this reason, a deeper sedation can be useful when resection becomes unexpectedly demanding. An intravenous dose of propofol (10 mg/mL) can be injected and maintained using a target-controlled infusion with a progressive supplement of fentanyl.
Surgery
It must be stressed that the atmosphere of the operating room deserves particular attention. It must be kept quiet and professional. All personnel should be well-trained and should avoid direct comments about the pathologic condition, as well as agitated status or inopportune noise. Extensive use of low-volume, calm, and relaxing music can help.
Technological progress and experience has allowed surgeons to enrich their repertoire of techniques. This article describes the classic triportal, biportal, and uniportal approaches that the authors have experience with.
Patient Selection
A patient being considered for nonintubated VATS wedge resections should have several characteristics. First, the features of the mass should be suitable for a quick wedge resection with an adequate resection margin free of tumor. In order to fit this mandatory prerequisite, 2 critical parameters should be taken into account: the diameter and location of the nodule. Generally, the maximal permitted diameter should not exceed 3 cm ; however, in the case of a safe nonintubated wedge, the authors recommend a much smaller size. In our opinion, this critical limit should be set to 2 cm, but we assume that the smaller the size results in easier and safer resection ( Fig. 2 ).
The mass should be peripherally located preferably no deeper than 1 cm from the external visceral pleura, or in alternative adjacent to the external margin of a fissure. Mass located in the fissure should be superficial and far from the pulmonary artery branches. Another demanding location for a nonintubated wedge resection is the basal surface of the lower lobes, which can become particularly problematic when the nodule is located in proximity to the inferior pulmonary vein. To better evaluate the exact distance from the nearest fissure, it may be helpful to visualize the nodule on computed tomography (CT) scan, according to sagittal and coronal planes. Fig. 3 shows a polyaxial map of the lung regions where a nodule can lie to be considered feasible for a nonintubated wedge resection.
Notwithstanding, the presence of pliable emphysematous tissue should allow the resection of a deeply located and otherwise unresectable nodule, especially if located in the apical regions of the lobes. Another major contraindication to neoplastic, radical, nonintubated wedge resection is imaging evidence of enlarged or clearly neoplastic mediastinal lymph nodes. In these conditions, the use of CT scan combined with PET can be of great use. Nevertheless, diagnostic resections are progressively gaining importance and will be a topic of future discussion.
Obviously, one should also consider general contraindications to nonintubated anesthesia, which are summarized in Box 1 .
VATS feasibility
Anamnestic or imaging absence of pleural adhesion
No previous homolateral thoracoscopic surgery
Normal coagulation tests and absence of bleeding disorders
Nonobesity (body mass index <30 kg/m 2 )
Nonintubated procedure feasibility
Signed, fully informed consent to awake nonintubated procedure
Easy accessibility to the airways
Stable and cooperative psychological profile
American Society of Anesthesiologists Physical Status Classification lower than III
Presence of comorbidity
TEA feasibility
Low risk of intraoperative seizure
Absence of brain edema
No spine deformities
No coagulopathy
Hemodynamic stability
Local anesthesia feasibility
No history of allergy to local anesthesia
Short-length of procedure
Patient Position
An important premise to remember for patient position is that the surgeon is operating on an awake patient; therefore, he or she must acquire and keep a very comfortable position for the duration of the procedure. As for surgery under general anesthesia and 1-lung ventilation, the patient should usually lie on lateral decubitus. If tolerable, the table should be flexed at the level of the nipple to allow a better exposure of the intercostal spaces ( Fig. 4 ). Similtaneouly, to decrease tension on the upside hip, a pillow can be placed between the legs. Some centers insert an additional bed sheet under the back of the patient to allow rapid change of position in the case of urgent intubation. However, in the event of nodule sited in the most anterior region of the lobes, the procedure may be performed in a semisupine position through a uniportal approach similar to that adopted in cases of thymectomy.
Surgeon and Equipment Positions
In the authors’ experience, the surgeon preferably stands facing the patient. The first assistant stands on the opposite side of the surgeon and, if a second assistant is available, he or she holds the camera standing caudally to the surgeon. The scrub nurse stands sideways to the first assistant. The main video monitor and the anesthesiologist occupy a position above the head of the patient. The suction devices and the electrocautery and energy tools are placed at the side of the operating table. A water seal system should be always kept ready on the instrument table.
Armamentarium
All the instruments are common to those used for VATS, such as a 30-degree thoracoscope, endoclamps, endostaplers, endoclip appliers, and the energy devices, either radiofrequency or ultrasound. New dedicated instruments are indispensabile for uniportal access. These tools are usually long, narrow-shafted, bent, and double-hinged.
In cases of urgent intubation, the anesthesiologist should have ready a double-lumen tube, laryngeal mask, fiberoptic bronchoscope with a video-assisted system, and an endobronchial blocker to safely assess the most suitable device according to the situation.
Classic Triportal Surgery
The classic triportal approach was the first access introduced for nonintubated video-assisted wedge resections in peripheral lung cancer. Due to the multilocation of the ports, this approach should be accomplished under TEA that can simultaneously cover the 3 or 4 metameric regions involved in the procedure.
The authors place the 3 ports following the so-called baseball-diamond setting, with the camera in the center as the homebase, pointing to the lesion as the second base, and with the remaining 2 operative ports placed as first and third bases, respectively ( Fig. 5 ).
