Totally thoracoscopic pulmonary anatomic segmentectomies: technical considerations

Nanoparticle-based CT visualization of pulmonary vasculature for minimally-invasive thoracic surgery planning

Purpose

To evaluate CF800, a novel lipid-based liposomal nanoparticle that co-encapsulates indocyanine green (ICG) and iohexol, for CT imaging of pulmonary vasculature in minimally-invasive thoracic surgery planning.

Methods

CF800 was intravenously administered to 7 healthy rabbits. In vivo CT imaging was performed 15 min post-injection, with a subset of animals imaged at 24h, 48h, and 72h post injection. Signal-to-background ratios (SBR) were calculated at the inferior vena cava and compared across time-points. A similar protocol was applied to 2 healthy pigs to evaluate the feasibility and efficacy in a large animal model. To evaluate the feasibility of clinical application, a survey was completed by 7 surgical trainees to assess pre- and post-injection CT images of rabbits and pigs. Responses on the discernibility of pulmonary vasculature sub-branches and comfort level to use the images for pre-operative planning were collected and analyzed.

Results

CF800 injection improved visualization of pulmonary vessels in both rabbit and pig models. The SBR of rabbit pulmonary vasculature was significantly higher after CF800 injection (range 3.7–4.4) compared to pre-injection (range 3.3–3.8, n = 7; p<0.05). SBR remained significantly different up to 24 hours after injection (range 3.7–4.3, n = 4; p<0.05). Trainees’ evaluation found the post-injection CT images had significantly higher discernibility at the second vessel branch generation in both rabbit and pig models. Trainees identified smaller vasculature branch generations in the post-injection images compared to the pre-treatment images in both rabbit (mean 6.7±1.8 vs 5.4±2.1; p<0.05) and pig (mean 6.7±1.8 vs 5.4±2.1; p<0.05). Trainees were significantly more comfortable using post-injection images for surgical planning compared to the pre-injection images (rabbit: 8.1±1.1 vs. 4.7±2.1; pig: 7.6±2.1 vs. 4.9±2.2; p<0.05).

Conclusion

CF800 provides SBR and contrast enhancement of pulmonary vasculature which may assist in pre-surgical CT planning of minimally invasive thoracic surgery.

Postoperative morphine consumption and anaesthetic management of patients undergoing video-assisted or robotic-assisted lung resection: a prospective, propensity score-matched study

Background

Robotic assistance is increasingly being used for treatment of early stage of non-small cell lung cancer. Our objectives were to compare the morphine consumption during the postoperative 48 hours after robotic-assisted thoracic surgery and that after video-assisted thoracic surgery as well as compare the patient's haemodynamic and respiratory function during the procedures.

Methods

This observational, prospective study was conducted in a single referral centre for thoracic surgery from January 2016 to March 2017. Patients who were scheduled to undergo surgical lung resection were included. A propensity score based on age, sex, American society of Anesthesiology score was used between groups. Linear regression analyses were used to determine the mean difference in the postoperative morphine consumption. We also compared the haemodynamic and respiratory function during the two procedures.

Results

Among the 194 patients included, 105 (54%) and 89 (46%) underwent video and robotic surgery, respectively. Total 75 of each group were matched using the propensity score. The consumption of morphine was 23.0 (16.5-39.0) mg and 33.0 (19.3-46.5) mg (P=0.05) in the video and robotic groups, respectively. Linear regression revealed an average difference β (95% CI) of 6.76 mg (0.32-13.26) (P=0.04) in the morphine consumption after adjusting for the body mass index and local anaesthetic use. Robotic surgery was associated with worse haemodynamic and respiratory function than video surgery.

Conclusions

As compared with video, robotic surgery was associated with increased use of morphine and greater alteration in the haemodynamic and respiratory functions.

Perioperative outcome after open and thoracoscopic segmentectomy for the treatment of malignant and benign pulmonary lesions: a propensity-matched analysis

Background

The aim of this study was to compare the perioperative outcome of patients receiving anatomic segmentectomy either by open surgery or video-assisted thoracoscopic surgery (VATS). To assess the short-term morbidity of the procedure itself, lung cancer patients in all stages as well as patients with pulmonary metastases and benign lesions scheduled for segmental resection were enrolled in this study.

Methods

A retrospective analysis of prospectively collected data on 445 consecutive patients that underwent segmentectomy either by VATS (n=233) or thoracotomy (n=212) was performed. A propensity-matched analysis was conducted based on age, gender, smoking history, histology, tumor size, forced expiratory volume in 1 second (FEV1) and history of previous pulmonary resections. The matched sample included two groups of 140 patients each.

Results

Both study groups were comparable with respect to age, gender, smoking history, diagnosis, tumor size, pulmonary function and history of previous pulmonary resections. VATS segmentectomy was associated with decreased length of stay (7.4 vs. 9.5 days, P<0.001), drainage treatment time (4.7 vs. 5.9 days, P=0.012) and severe postoperative complications (1.4% vs. 7.1%, P=0.018).

Conclusions

VATS segmentectomy is safe and effective for the treatment of benign and malignant pulmonary lesions. Compared with open thoracotomy, it is associated with shorter hospitalization time and decreased number of severe complications. The preservation of functional lung tissue, combined with a minimally invasive approach, make VATS segmentectomy highly suitable for patients with reduced pulmonary function or severe comorbidities.

Anatomical variations and pitfalls to know during thoracoscopic segmentectomies

The rate of sublobar resection (SLR) for early-stage non-small cell lung carcinoma (NSCLC) is increasing, mainly because of a growing rate of early-stage lung carcinomas and ground-glass opacities. More and more SLRs are now performed by a thoracoscopic, a video-assisted or a robotically-assisted approach. Although surgeons are performing pulmonary segmentectomies for years, they need a better understanding of anatomy when using a closed chest approach, because vision is more limited and they cannot stretch and expose the parenchyma and broncho-vascular elements. In this article, we will describe most of the significant anatomical variations we have encountered during a consecutive series of 390 full thoracoscopic segmentectomies, either at surgery or preoperatively by studying the 3-dimensional (3D) modelisation.

VATS segmentectomy: past, present, and future

Video-assisted thoracoscopic surgery (VATS) has gradually been implemented in thoracic surgery, and the VATS approach has now been extended to technically challenging procedures, such as segmentectomy. The definition of VATS segmentectomy is changing over time, and the repertoire of segmentectomy is getting wider with increasing reports on atypical segmentectomy. VATS segmentectomy bears surgical, oncological, and technical advantages; however, there are still areas of controversy, particularly regarding oncological outcomes. The indication of VATS segmentectomy is diverse and is used for treating lung cancer, metastatic lung tumors, or a variety of nonmalignant diseases. It is particularly valuable for the lung-sparing resection of deeply located small nodules or repeated surgery for multiple lung lesions. VATS segmentectomy requires a thorough analysis of segmental anatomy and a tailored preoperative planning with the assessment of surgical margins. Technical challenges include intraoperative navigation, methods to identify and dissect the intersegmental plane, and the prevention of air leakage. This review will discuss the present state of VATS segmentectomy, with a focus on past studies, current indications and techniques, and future view.

Technique of robotic segmentectomy

Robotic segmentectomy can be a useful technique for patients with suboptimal pulmonary reserve, or for small peripheral stage I tumors. Port placement and conduct of operation is described for the various segmentectomies. Results for robotic segmentectomy are comparable to that for video-assisted thoracoscopic surgery (VATS) segmentectomy.

Thoracoscopic anatomic segmentectomies for lung cancer: technical aspects

Although the interest for thoracoscopic sublobar resections (TSLR) is rising, its use for treating non-small cell lung carcinoma (NSCLC) is still controversial because publications dealing with survival and recurrence rate provide contradictory results. If applied to the resection of lung cancer, thoracoscopic segmentectomies must be performed according to oncological criteria. The aim of this technical paper is to give some technical details on thoracoscopic segmentectomies for the treatment of malignancies. Our experience is based on 235 thoracoscopic anatomical segmentectomies performed in 232 patients for a malignant lesion between January 2007 and July 2016. Indication for segmentectomy was a proven or suspected NSCLC in 184 and suspected metastasis in 51 patients. Intraoperative and postoperative data were recorded in a prospective manner. There were eight conversions into a posterolateral thoracotomy (3.4%) and seven unplanned additional pulmonary resections for an oncological reason (3%). We discuss some technical refinements that could minimize these adverse events and make thoracoscopic segmentectomy a safe and reliable procedure.

Open, thoracoscopic and robotic segmentectomy for lung cancer

While lobectomy is the standard procedure for early stage lung cancer, the role of sublobar resection is currently under investigation for selected patients with small tumors. In this review, studies reporting outcomes on open, thoracoscopic and robotic segmentectomy were analyzed. In patients with stage I lung cancer, with tumors <2 cm in diameter and within segmental anatomic boundaries, segmentectomy appears to have equivalent rates of morbidity, recurrence and survival when compared to lobectomy. Segmentectomy also resulted in greater preservation of lung function and exercise capacity than lobectomy. It appears reasonable to consider segmentectomy for patients with stage I lung cancer (particularly in air-containing tumors with ground glass opacities) where tumors are <2 cm in diameter and acceptable segmental margins are obtainable, especially in patients with advanced age, poor performance status, or poor cardiopulmonary reserve. The results of two ongoing randomized controlled trials (CALGB 140503 and JCOG0802/WJOG4607L) and additional well-designed studies on open, thoracoscopic, and robotic segmentectomy will be important for clarifying the role of segmentectomy for lung cancer.