Video-Assisted Thoracoscopy: Multiportal Uniportal

Video-Assisted Thoracoscopic Surgery Versus Open Thoracotomy

Contrary to conventional incisions—such as posterolateral thoracotomy—port holes require smaller incisions which would be associated with reduced inflammatory response, better respiratory mechanics, improved respiratory muscle recovery, and certainly lesser pain. Thoracoscopic procedures have become more frequently comprising a wide range of procedures and represent a reliable minimal invasive alternative for high-risk patients.

Initial reports highlighted benefits of VATS in reducing overall complications and decreasing hospital stay. Furthermore, the thoracoscopic approach was found to be more favorable in terms of intensive care unit (ICU) stay time and postoperative pneumonia despite preoperative comorbidities. In several studies, it was shown that VATS minimized complications and enhanced the quality of life in the postoperative period, with less postoperative pain, better pulmonary function outcomes, shorter overall hospital length of stay, and faster return to normal activities. ^, In 2010, the American College of Surgeons Oncology Group published data of approximately 1000 patients and found that thoracoscopic lobectomy was associated with lower pulmonary complications (atelectasis, chest tube drainage) and shorter length of stay. In 2016, the European Society of Thoracic Surgeons reported results from 235 centers which included 5500 patients (selected among 26,000 according to propensity score). Major cardiopulmonary complications were significantly lower in the VATS group compared with the thoracotomy group (15.9% vs. 16.9%; P = .0094). Length of stay was shorter among the thoracoscopic group as expected ( P = .003). Mortality at discharge was also lower in the VATS group, which, however, needs to be cautiously commented according to authors because of some missing data. A more recent trial by Nwogu et al. has compared VATS with open thoracotomies as length of stay (LOS) for primary outcome. The VATS group had significantly lower LOS (5.4 vs. 8 days; P < .001). Moreover, incidence of complications was consistent with the primary outcome favoring the VATS group (6% vs. 16%; p = .0001). Thoracoscopic surgery is associated with reduced injury, stress response, and may enhance recovery of patients in thoracic surgery. The short-term outcome appeared favorable for thoracoscopic surgery.

In the recently published: “Guidelines for enhanced recovery after thoracic surgery (ERATS),” VATS was recommended for lung resection for early-stage lung cancer with a “high” evidence level and “strong” recommendation grade, stating that “the benefits are even more marked in patients with poor respiratory reserve.”

Long-term results are controversial; studies show either similar results of both approaches, or better results for VATS in terms of survival. Sugi et al. reported a similar oncologic outcome in VATS compared with conventional lobectomy for the following 5 years. Similarly, Whitson et al. did not find any difference in survival between thoracoscopy and thoracotomy. Recently, one center study by Oda et al. in patients with early lung cancer, reported better 5-year survival in patients undergoing thoracoscopic resection. Short-term variables (blood loss, hospital stay, C-reactive protein [CRP] levels) were also significantly advantageous in the thoracoscopy group. The authors speculated that it could be related to lesser tissue damage and inflammatory response screened by CRP values. Other studies confirm that the long-term (5 years) survival was better with VATS when compared with open surgery for early-stage lung cancer ^, ( Fig. 31.1 ). Another recent study comparing VATS to open thoracotomy for cT1–T2 N1 M0 nonsmall cell lung cancer (NSCLC) showed that VATS had no significant difference in long-term survival, with shorter LOS and similar nodal upstaging rates, considering it suitable for the treatment of NSCLC.

Today, VATS is recognized by international guidelines as preferred over thoracotomy for treatment of early-stage NSCLC.

An interesting retrospective study revealed similar costs for thoracoscopic or traditional lobectomies. Operative cost was significantly higher with VATS, whereas total hospital cost was similar with traditional lobectomy, but a shorter stay in the thoracoscopic group and increased patients’ turnover abolished the temporary economic issue of conventional approach.

Uniportal Video-Assisted Thoracoscopic Surgery

In a period of less than 20 years, there has been a rapid evolution in the surgical technique of VATS: the classical three-port approach was initially changed to a two-port strategy, and soon afterwards, there was a trend toward a one-port technique, where the camera was moved to the utility port, the camera’s port was abandoned, and the entire procedure was completed using just one incision. Uniportal VATS was first described in 2001, and then reported for simple procedures, such as lung biopsies and spontaneous pneumothorax in 2005.

The expansion of the technique was achieved following the developments by Gonzalez-Rivas et al. in the next 10 years, where the technique was used for more complex procedures, such as pulmonary anatomic and complex resections for the treatment of lung cancer. This strategy achieves a direct vision of the targeted tissue and of the pulmonary hilum. This fact, together with the accession of parallel instrumentation, achieves an approach similar to the open surgery view and maneuvers, making the surgeons feel more comfortable while operating, compared with other VATS strategies. Today, the technique has been adopted, reproduced, and reinforced by the surgical community; however, it is limited by the significant learning curve. ^,

Compared with conventional VATS, UniVATS has been shown to be beneficial with shorter LOS in the hospital, duration of drainage, and reduced overall morbidity. One—instead of three—incision is associated with less inflammation and less pain, leading to reduced postoperative complications, with an overall better outcome. It has been used not only in operations like lobectomy or wedge resection but also in more complicated procedures like pneumonectomy, sleeve resection or tracheal and carinal resections.

It should be noted that some trials report no difference between uniportal and multiport VATS lobectomy. Perna et al. have compared uniportal video-assisted lobectomy (group A; n = 51) and other video-assisted thoracoscopic lobectomy techniques (group B; n = 55). The median visual analog pain score in the first 3 days did not show statistically significant differences. Likewise, the median morphine use in the first 3 days did not show statistically significant differences. There was no difference in timing to remove the paravertebral catheter and the chest drain and the duration of the postoperative hospital stay. There was no difference in postoperative complications. In ERATS protocols, it has been stated that “The number of ports used does not appear to affect outcomes, and so, one VATS approach cannot be recommended over another.” As a matter of fact, more and more high quality studies are still necessary to evaluate the potential benefits of this technique. The anesthetic management, including ventilation, for uniportal VATS does not differ from that performed for classical VATS.

Subxiphoid Uniportal Video-Assisted Thoracoscopic Surgery

The subxiphoid approach began its evolution in 1999. First implemented for mediastinal pathologies, in 2014, a subxiphoid UniVATS left upper lobectomy was reported. Following that, many procedures, such as wedge resections, segmentectomies, lobectomies, and even pneumonectomies have been performed by this approach. There are two major advantages of this technique: (1) intercostal nerve injury related to the incision and instrumentation is avoided, and (2) it will allow approaching bilateral lesions from a single incision without changing the patient’s position. Avoidance of intercostal nerve injury has been shown to be associated with significantly lower postoperative pain compared with intercostal UniVATS.

Robotic-Assisted Thoracic Surgery

Robotic-assisted thoracic surgery (RATS) is covered in Chapter 52 in this book in detail. It should be considered as an important step of the rapid changes in the practice of thoracic surgery and anesthesia. A subcostal VATS approach (with or without robotic help) is also one of these promising steps.

Preoperative Risk Stratification

Preoperative evaluation with risk stratification and scoring systems are extensively explained in Chapter 8 of this book. Regarding VATS, it should be noted that some systems take also “operation-related” risk factors into consideration (e.g., considering pneumonectomy as “high-risk”); however, to our knowledge, none of these risk stratifications and scoring systems differentiated between open thoracotomy and VATS as different risk factors. The risk of a patient undergoing open thoracotomy with similar comorbidities and extent of resection is higher than the patient undergoing VATS. This part will therefore focus on “common” criteria.

Improvements of surgical techniques and advances in anesthesia have resulted in an overall improved outcome. But at the same time, those improvements allowed patients who previously were not considered surgical candidates to now be offered major resections. These patients are older, with multiple comorbidities which in many cases are uncontrolled or not treatable, making the perioperative period challenging, and probably leading to an increase in postoperative complications and decrease survival. Therefore preoperative evaluation and preparation of patients who will undergo a VATS procedure should be revised separately.

Perioperative mortality represents a serious worldwide public health problem. Thoracic surgery deserves special interest because postoperative complications are significantly high (up to 27% in a recent review) ( Fig. 31.2 ). Preoperative assessment and screening of high-risk patients must identify the patient that would benefit from optimizing measures. Increase in patient comorbidities and an increase in awareness during the perioperative period is a relatively new topic which is part of the ERAS (enhance recovery after thoracic surgery) guidelines. A team approach makes sense for this population while assessing cardiac risk, planning optimizing measures, organizing oncologic follow-up, and judging operability. Thus an experienced team should be composed of a pulmonologist, oncologist, thoracic surgeon, and anesthesiologist as well as the patient and the relatives.

The first step of preparation can be initiated with cardiac evaluation to determine preexisting risk factors and to treat before surgery. The revised cardiac risk index has been adapted for thoracic surgery ( Table 31.1 ). Three to four subgroups are defined in this scoring system as A (0 point), B (1–1.5 points), C (2–2.5 points), or D (>2.5 points); the latter two described as high risk. The incidence of cardiac event varies in groups for A less than 1.5%, for B 5.8%, for C 19%, and for D 23%. The thoracic revised cardiac risk index (ThRCRI) can discriminate high-risk patients—groups C and D —and may allow for identification of patients who would benefit from additional cardiac evaluation.

A subsequent cardiac issue—generally neglected—is right ventricular (RV) function, which remains affected from the second postoperative day to the second month. Postthoracotomy impaired RV ejection fraction is a recognized phenomenon usually related to elevated pulmonary vascular pressures but also to reduced compliance. Thoracoscopic surgery compared with thoracotomy offers advantages in terms of RV function in the early postoperative course for elderly patients. Not surprisingly, the extent of lung resection directly affects RV changes. Pneumonectomy is found to be associated with more pronounced RV dysfunction compared with lobectomy. Further studies are needed to determine the best predictor for preoperative assessment of RV. Natriuretic peptides seem promising in thoracic patients to detect some CV complications, especially for prediction of postoperative atrial fibrillation. ^,

Pulmonary evaluation for lung surgery includes spirometry, diffusion capacity, and exercise tests if needed, as summarized in Fig. 31.3 . Although patients with low risk can be cleared for surgery, in high-risk patients, cardiopulmonary exercise testing should be considered. In a newly introduced algorithm, a slope of minute ventilation to CO2 output ratio seems promising. A slope of more than 34 was associated with increased mortality. In fact, an increased ratio could be explained by respiratory inefficiency and appeared to be associated with increased mortality.

Preoperative Optimization and “Prehabilitation” (See Chapter 9 )

Besides risk stratification, the aim of a preoperative evaluation is optimization and rehabilitation. The anesthesiologist as perioperative physician has to manage treatable conditions to reduce complications. The initial measure should be smoking cessation , as it is a considerable risk factor in lung cancer for both short- and long-term outcomes. ^, Smoking impairs mucociliary ability to remove pathogens or foreign bodies from the airway and alveolar macrophage activity. In a retrospective study performed with more than 20,000 subjects, smoking cessation was found to be associated with reduced in-hospital morbidity and mortality independent of time interval and amount of smoking. A prospective study affirmed similar results among thoracoscopic lung surgery patients; with incidence of postoperative pulmonary complications (PPCs) 10 times greater in active smokers compared with never smokers and 2 times compared with ex-smokers. Cessation of more than 6 weeks resulted in reduced LOS. However, optimal timing for cessation before surgery has yet to be determined.

Iron deficiency anemia is very common worldwide and affects surgical populations. Screening and treatment of anemia is recommended for expected blood loss greater than 500 mL before surgery. The target value of hemoglobin commonly accepted for preoperative iron therapy is 13 g/dL and replacement is achieved by intravenous (IV) iron if there is a window of less than 6 weeks to surgery. In case of chronic inflammation, diagnosis requires additional findings; serum ferritin levels less than 100 mcg/L or transferrin saturation less than 20% can be considered as inadequate iron stores. Anemia has been associated with worse survival in lung cancers. On the other hand, transfusion itself was related with early recurrence and shorter survival in a meta-analysis of 23 studies. The authors conclude with recommendation of stricter transfusion policy, especially for early stages. Supporting recent results from 15 years’ data of a single center with worse outcome and increased recurrence of blood transfusion. The difference seemed to appear with more than one unit of blood transfusion. Patient blood management, a concept that aims to rationalize blood transfusion, should be applied as possible also in VATS operations.

A relatively new issue of optimization is preoperative habilitation “ prehabilitation, ” which consists of training patients with respiratory or cardiopulmonary exercises before surgery. The expectation is to improve physical performance, to increase exercise tolerance, and to improve health-related quality of life for a well-conditioned patient. Types of exercise are endurance or high-intensity interval trainings (HIIT). The first one consists of moderate intensity efforts and 60 to 120 minutes in daily practice over 6 to 12 weeks. On the other hand, the second one is performed at a high intensity in relatively brief training periods. Licker et al. investigated effects of HIIT and conventional preoperative optimization (nutritional measures, smoking, and alcohol cessation) in patients undergoing lobectomy. The training group attained significantly better peak O2 consumption and 6-minute walking values. Pulmonary complications were significantly lower in the prehabilitation group because of decreased incidence of atelectasis. However, composite outcome, death, and in-hospital complications which was the primary outcome, were similar between groups. Moreover, beneficial effects of a rehabilitation program can be more prominent in patients with respiratory impairment during induction chemotherapy. Initial reports are encouraging with improved aerobic performance and respiratory volumes. Is this progress sufficient to prevent postoperative complications? An adequately powered randomized controlled trial (RCT) that is presently ongoing multicentric study (INSPIRE) hopefully will provide more concrete information.

History

Historically, lung isolation essays were started with physiologic animal studies by C. Bernard and E. Pflüger in the 19th century. The setup was adapted to volunteers by Loewe and von Schrotter at the beginning of the 1900s, again, for cardiopulmonary physiologic studies. Introduction of the endotracheal tube (ETT), by Gale and Waters, followed by the introduction of the double-lumen tubes (DLTs). The 1950s presented the first double-cuffed double-lumen tube described by Carlens. DLTs designed by Robertshaw were introduced first in red rubber in the 1960s; 20 years later, they are marketed as disposable polyvinyl chloride, and are used worldwide. A rubber bronchial blocker (BB) was first used (positioned by radiography) in the 1930s by Archibald. The use of the fiberoptic bronchoscope was considerably later in the 1980s and constituted a huge advancement in thoracic anesthesia.

Indications

The historical classification of indications for one-lung ventilation (OLV; namely, absolute vs. relative) is not target-oriented and sometimes confusing. From that historical point of view, every VATS operation should be considered as an “absolute” indication of OLV. Currently, thoracic anesthetists agree on the classification of lung isolation versus lung separation: the isolation of the lungs means a completed “anatomic” sealing (conditions like massive pulmonary bleeding, air leak as a result of bronchopleural fistulae, pneumonia with pus, etc.); whereas the separation of the lung means a “functional” sealing. Because most VATS operations require just lung separation and not isolation, both DLTs and BBs can be used. DLT is the most common device used in OLV, but it should be known that in some conditions, BBs can be a more rational alternative ( Table 31.2 ).