Management of Intersegmental Plane on Pulmonary Segmentectomy Concerning Postoperative Complications

Identifying the intersegmental plane for segmentectomy using the open insufflation technique

Accurate identification of the intersegmental plane is the key to successful segmentectomy. This case series included 41 patients who underwent uniportal thoracoscopic segmentectomy using the open insufflation method to identify the intersegmental plane for pulmonary nodules. The median age of the patients was 58 (range 35-73) years, and 63.4% were female. Malignant pulmonary nodules accounted for 80.5% of cases and were staged as 0-IA2. Seventeen patients underwent a single subsegmentectomy or single segmentectomy, and 24 underwent combined subsegmentectomy or subsegmentectomy combined with segmentectomy. There was no conversion to multiportal video-assisted thoracoscopic surgery, open surgery, or lobectomy. The median operative time was 84 (range 45-194) min, and the median blood loss was 50 (range 10-150) ml. The median chest tube duration and postoperative hospital stay were 2 (range 1 - 7) days. One (2.4%) developed an air leak for >5 days. No deaths occurred within 30 days after surgery.

Development and validation of a nomogram for predicting pulmonary complications after video-assisted thoracoscopic surgery in elderly patients with lung cancer

Background

Postoperative pulmonary complications (PPCs) significantly increase the morbidity and mortality in elderly patients with lung cancer. Considering the adverse effects of PPCs, we aimed to derive and validate a nomogram to predict pulmonary complications after video-assisted thoracoscopic surgery in elderly patients with lung cancer and to assist surgeons in optimizing patient-centered treatment plans.

Methods

The study enrolled 854 eligible elderly patients with lung cancer who underwent sub-lobectomy or lobectomy. A clinical prediction model for the probability of PPCs was developed using univariate and multivariate analyses. Furthermore, data from one center were used to derive the model, and data from another were used for external validation. The model's discriminatory capability, predictive accuracy, and clinical usefulness were assessed using the receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis, respectively.

Results

Among the eligible elderly patients with lung cancer, 214 (25.06%) developed pulmonary complications after video-assisted thoracoscopic surgery. Age, chronic obstructive pulmonary disease, surgical procedure, operative time, forced expiratory volume in one second, and the carbon monoxide diffusing capacity of the lung were independent predictors of PPCs and were included in the final model. The areas under the ROC curves (AUC) of the training and validation sets were 0.844 and 0.796, respectively. Ten-fold cross-validation was used to evaluate the generalizability of the predictive model, with an average AUC value of 0.839. The calibration curve showed good consistency between the observed and predicted probabilities. The proposed nomogram showed good net benefit with a relatively wide range of threshold probabilities.

Conclusion

A nomogram for elderly patients with lung cancer can be derived using preoperative and intraoperative variables. Our model can also be accessed using the online web server https://pulmonary-disease-predictor.shinyapps.io/dynnomapp/. Combining both may help surgeons as a clinically easy-to-use tool for minimizing the prevalence of pulmonary complications after lung resection in elderly patients.

Division of the intersegmental demarcation using the “modified hand‐tearing method” is safe and feasible in thoracoscopic anatomical segmentectomy

Background

The accurate and safe division of the intersegmental demarcation (ISD) is critical and challenging during thoracoscopic anatomical segmentectomy. Here, we provide an improved technique which emphasizes the application of an electric hook and blunt division of ISD. The technique is termed as the “modified hand‐tearing method” (MHT method) with combined application of an electric hook and staplers.

The study aimed to review the outcomes of patients who underwent thoracoscopic anatomical segmentectomy, with or without the MHT method in our institute and assess its feasibility and safety. In addition, we compared the feasibility between video‐assisted thoracoscopic surgery (VATS) and robot‐assisted thoracoscopic surgery (RATS) using the MHT method.

Methods

From 2018 July to 2021 June, we retrospectively analyzed 701 patients who underwent segmentectomy. Using propensity score matching, data of two well‐matched pairs of 276 cases in the MHT method and non‐MHT method groups, and two well‐matched pairs of 40 cases in the VATS and RATS subgroups were obtained. The clinical and perioperative characteristics of patients were compared between groups.

Results

Compared with the non‐MHT method group, the MHT method group had shorter operation time and shorter postoperative hospital stay. Period of chest tube drainage and postoperative total drainage and postoperative complications had no between‐group difference. Compared with VATS, the RATS subgroup had less intraoperative bleeding and shorter postoperative hospital stay.

Conclusion

Division of ISD using the MHT method has advantages in precision and ease of operation, so it has the potential to become a feasible and effective method for thoracoscopic anatomical segmentectomy.

Efficacy of the Segment-Counting Method in Predicting Lung Function and Volume Following Stapler-Based Thoracoscopic Segmentectomy

Purpose: To investigate the accuracy of a segment-counting method in predicting lung function and volume after stapler-based thoracoscopic segmentectomy in comparison with lobectomy.

Methods: Between 2014 and 2018, patients who underwent these procedures were retrospectively reviewed. Thoracic computed tomography and spirometry data before and 1 year after the surgery were assessed. We evaluated the differences between the predicted values using a segment-counting method and the actual postoperative values for lung function and volume in each group. Sub-analyses were also performed to assess the impact of the number of staples and resected segments in predicting patient outcomes.

Results: We included 116 patients (segmentectomy, 69; lobectomy, 47). Actual postoperative lung function and volume values matched the predicted values in the stapler-based segmentectomy group, and significantly exceeded the predictions in the lobectomy group (P <0.01). Sub-analyses revealed lower postoperative lung function values than predicted existed after single segmentectomy, with an odds ratio of 3.29 (95% confidence interval: 1.02–10.70, P = 0.04) in a multivariable analysis. The degree of predicted error regarding lung function was negligible.

Conclusions: The segment-counting method was useful in predicting lung function after stapler-based thoracoscopic segmentectomy. Segmentectomy rarely yielded lower- than-predicted lung function and volume values.

Determination of initial airtightness after anatomical laser segmentectomy in an ex vivo model

If a pulmonary pathology can be removed by anatomical segmentectomy, the need for lobectomy is obviated. The procedure is considered oncologically equivalent and saves healthy lung tissue. In every segmentectomy, lung parenchyma must be transected in the intersegmental plane. Using an ex vivo model based on porcine lung, three transection techniques (monopolar cutter + suture, stapler, and Nd:YAG laser) are to be compared with respect to their initial airtightness. At an inspiratory ventilation pressure of 25 mbar, all three preparations were airtight. Upon further increase in ventilation pressure up to 40 mbar, the laser group performed best in terms of airtightness. Since thanks to its use of a laser fibre, this technique is particularly suitable for minimally invasive surgery; it should be further evaluated clinically for this indication in the future.

Prevention of Postoperative Prolonged Air Leak After Pulmonary Resection

Postoperative prolonged air leaks (PALs) occur after thoracic surgery in which lung parenchyma is resected, divided, or manipulated. These air leaks can place patients at risk for intensive care unit readmissions, longer hospital length of stay, and infectious complications. Studies have been conducted to identify patients who are at risk for air leak and several methods have been examined for the prevention and treatment of PALs. A standard method of air leak prevention or treatment has not been established. This article discusses the prophylactic measures that have been studied for the prevention of PALs following lung surgery.

How to identify intersegmental planes in performing sublobar anatomical resections

Pulmonary segmentectomy is a common surgical procedure in thoracic surgery nowadays. Though this technique helps preventing postoperative pulmonary function loss, potential challenges are the management of air leaks and the difficulty of palpating ground-glass components during surgery, as well as how to deal with the intersegmental planes. Several techniques have been proposed for the identification and treatment of the intersegmental planes during sublobar anatomical resections: this review focuses on preoperative planning and workup and intraoperative strategies. Three-dimensional computed tomography bronchography and angiography (3D-CTBA), virtual-assisted mapping (VAL-MAP) using bronchoscopy multi-spot dye marking and three-dimensional computed tomography (3D-CT) are preoperative tools that may facilitate the planning of operation. Inflation-deflation techniques, infrared-fluorescence-enhanced method combined with bronchial and intravenous injection of indocyanine green (ICG) and near-infrared fluorescence (NIF) mapping with ICG have been described as intraoperative strategies to identify the intersegmental plane. The treatment and section of the intersegmental planes is mainly accomplished by stapler and electrocautery or energy devices. The use of staplers reduces postoperative air leaks, bleeding risks and operative time but seems to reduce preserved lung volume, compromising adjacent lung expansion; in addition, higher costs and sometimes non-adequate oncological margins, being a non-anatomical technique have been described. The electrocautery and energy devices allow for a more anatomical and precise dissection maintaining safe oncological margins, with a better lung expansion and so an increased postoperative lung function. Time consuming procedure and frequent requirement of aero-haemostatic tools to treat air and blood leaks are the main drawbacks. In conclusion, there are several methods to identify and treat the intersegmental planes but there are no significant differences between the different tools, therefore the use of one technique rather than another depends overall on surgeon's preference and the location of the segment.

Management of the inter-segmental plane using the "Combined Dimensional Reduction Method" is safe and viable in uniport video-assisted thoracoscopic pulmonary segmentectomy

Background

The management of the intersegmental plane (ISP) is challenging during uniport video-assisted thoracoscopic (VATS) pulmonary segmentectomy. Staplers and electrocautery have been used extensively in ISP management. However, both of them have their respective drawbacks. Currently, we have provided a revised technique termed as "Combined Dimensional Reduction Method" (CDR method), for managing the ISP with combined application of ultrasonic scalpel and staplers. The study aimed to review the outcomes of patients who underwent uniport VATS segmentectomy with or without the CDR method in our institute and assess the feasibility and safety of the CDR method.

Methods

From March 2017 to February 2018, 220 patients who underwent uniport VATS segmentectomy were retrospectively reviewed. By using IQQA software, pulmonary structures were reconstructed as three-dimensional (3D) images, making the targeted structures could be identified preoperatively. For the management of the ISP, in the CDR group, we firstly used the ultrasonic scalpel to trim the 3D pulmonary structure along the intersegmental demarcation, making the remaining targeted parenchyma both sufficiently thin enough and located on a 2D plane; thus, enabling easy use of staplers in managing ISP. Whereas, in the non-CDR group, we only use the staplers to manage the ISPs. The clinical characteristics, complications, and postoperative pulmonary functions were compared between the two groups.

Results

Propensity score analysis generated 2 well-matched pairs of 71 patients in CDR and non-CDR groups. There was no 30-day postoperative death or readmission in either group. The CDR group was significantly associated with the shorter operative time (178.3±35.8 vs. 209.2±28.7 min) (P=0.031) and postoperative stay (4.5±2.3 vs. 5.7±4.2 days) (P=0.041), compared to the non-CDR group. Moreover, no significant difference was observed in blood loss, a period of chest tube drainage, a period of ultrafine tube drainage, and postoperative pulmonary complications between the two groups. Moreover, the recovery rate of postoperative forced expiratory volume in 1 second (FEV1) or vital capacity (VC) at 1 and 3 months after segmentectomy was comparable between them.

Conclusions

The CDR method could make segmentectomy easier and more accurate, and therefore has the potential to be a viable and effective technique for uniport VATS pulmonary segmentectomy.

Division of the intersegmental plane using electrocautery for segmentectomy in clinical stage I non-small cell lung cancer

Background

Division of intersegmental planes is one of the important practical issues for segmentectomy to obtain feasible outcomes without relapse for clinical stage I non-small cell lung cancer. Almost all surgeons perform this procedure using a stapler. However, division of intersegmental planes for segmentectomy can also be performed by electrocautery. In this article, we demonstrate the merits and drawbacks of division of the intersegmental plane by electrocautery for segmentectomy.

Methods

Of those 125 patients who underwent segmentectomy with clinical stage I primary lung cancer, we compared cautery cases (n=50) with stapler cases (n=75). The cautery group included 29 cases (58.0%) with partial use of a staple at the end of division.

Results

Operative time was significantly longer in cautery cases (281±72 min) than stapler in cases (235±86 min; P=0.003). No difference in the duration of chest tube placement was evident between cautery (3.0±3.0 days) and stapler groups (2.8±1.7 days; P=0.613). However, delayed air leakage occurred significantly more frequently in cautery cases (14.0%) than in stapler cases (4.0%; P=0.048). Five-year overall survival (OS) in clinical stage I was 94.7% in cautery cases and 80.5% in stapler cases (log-rank P=0.047). Five-year disease-free survival (DFS) was 80.0% and 71.3%, respectively (log-rank P=0.075).

Conclusions

The merits of cautery division include the ability to achieve meticulous division of the intersegmental plane and good preservation of the shape of residual segments. Conversely, the drawbacks include prolonged air leakage. Pleural suture or closure of residual segments may be useful to prevent delayed air leakage.