Variation in incidence, prevention and treatment of persistent air leak after lung cancer surgery

Effectiveness of Stitch With Pledget to Prevent Prolonged Air Leak in Thoracoscopic Lung Resection

INTRODUCTION

We previously demonstrated the usefulness of combining stitching with covering to seal alveolar air leaks in an animal model. This study aimed to clarify the effectiveness and feasibility of this sealing method in the clinical setting.

METHODS

Data of 493 patients who underwent thoracoscopic anatomical resection between 2013 and 2020 for lung cancer were retrospectively reviewed. Prolonged air leak was defined as chest drain placement lasting 5 d or longer due to air leak. Until July 2017 (early study period), we covered air leaks using mesh. However, for sealing (late study period), we additionally stitched leaks with pledget in patients at high risk of prolonged air leak. The pneumostasis procedure, intraoperative confirmation test of pneumostasis, and chest tube management were uniform during both periods.

RESULTS

The incidence of prolonged air leak was significantly lower in the late than in the early period (3.6% versus 12.5%), whereas pulmonary emphysema was more severe in the late period compared to the early period. Intraoperative failure of sealing air leaks was significantly reduced in the late period than in the early period. In both univariate and propensity score matching analysis, the study period was a significant predictor of prolonged air leak.

CONCLUSIONS

The combination of stitching and covering with mesh may contribute to reducing prolonged air leak incidence in patients undergoing thoracoscopic anatomical lung resection for lung cancer.

Suitable Patient Selection and Optimal Timing of Treatment for Persistent Air Leak after Lung Resection

OBJECTIVES

The choice of therapeutic intervention for postoperative air leak varies between institutions. We aimed to identify the optimal timing and patient criteria for therapeutic intervention in cases of postoperative air leaks after lung resection.

METHODS

This study utilized data from a prospective multicenter observational study conducted in 2019. Among the 2187 cases in the database, 420 cases with air leaks on postoperative day 1 were identified. The intervention group underwent therapeutic interventions, such as pleurodesis or surgery, while the observation group was monitored without intervention. A comparison between the intervention group and the observation group were analyzed using the cumulative distribution and hazard functions.

RESULTS

Forty-six patients (11.0%) were included in the intervention group. The multivariate analysis revealed that low body mass index (p = 0.019), partial resection (p = 0.010), intraoperative use of fibrin glue (p = 0.008), severe air leak on postoperative day 1 (p < 0.001), and high forced expiratory volume in 1 s (p = 0.021) were significant predictors of the requirement for intervention. The proportion of patients with persistent air leak in the observation group was 20% on postoperative day 5 and 94% on postoperative day 7. The hazard of air leak cessation peaked from postoperative day 3 to postoperative day 7.

CONCLUSIONS

This research contributes valuable insights into predicting therapeutic interventions for postoperative air leaks and identifies scenarios where spontaneous cessation is probable. A validation through prospective studies is warranted to affirm these findings.

Development of a multivariable prediction model for prolonged air leak after lung resection

OBJECTIVES

Prolonged air leak (PAL) is a common complication of lung resection. Research on predictors of PAL using a digital drainage system (DDS) remains insufficient. In this study, we investigated the predictive factors of PAL to establish a novel early postoperative prediction model for PAL.

METHODS

A retrospective cohort study and validation study were conducted. We examined patients who underwent lung resection with DDS at our institute. The relationship between the clinical factors and measurements of the DDS, including the difference between the set and measured intrapleural pressure (named: additional negative pressure [ANP]) at postoperative hour (POH) 3, with PAL was analyzed.

RESULTS

A total of 494 patients were enrolled, 29 of whom had PAL. Percent forced expiratory volume in 1 s <60%, ANP <1 cmH2O, air leak flow >20 mL/min and pleural adhesion findings at surgery were independent predictors of PAL according to a multivariable analysis. The PAL rate was clearly stratified according to our novel risk scoring system, which simply notes the presence of the above four factors, that is, the rate increases when the score increases. The area under the curve (AUC) of the receiver operating characteristic (ROC) analysis for this scoring system was 0.818. Analysis of the validation cohort (n = 133) revealed that this scoring system showed a sufficient ability to predict PAL.

CONCLUSIONS

ANP at POH 3 is an independent predictor of PAL. Thus, the risk-scoring system proposed in this study is useful for predicting PAL in the early postoperative period.

Sealing effectiveness of a novel NHS-POx based patch: experiments in a dynamic ex vivo porcine lung

Background

Sealants are used to prevent prolonged pulmonary air leakage (PAL) after lung resections (incidence 5.6-30%). However, clinical evidence to support sealant use is insufficient, with an unmet need for a more effective product. We compared a novel gelatin patch impregnated with functionalized polyoxazolines (NHS-POx) (GATT-Patch) to commercially available sealant products.

Methods

GATT-Patch Single/Double layers were compared to Progel®, Coseal®, Hemopatch® and TachoSil® in an ex vivo porcine lung model (first experiment). Based on these results, a second head-to-head comparison between GATT-Patch Single and Hemopatch® was performed. Air leakage (AL) was assessed in three settings using increasing ventilatory pressures (max =70 cmH2O): (I) baseline, (II) with 25 mm × 25 mm superficial pleural defect, and (III) after sealant application. Lungs floating on saline (37 ℃) were video recorded for visual AL assessment. Pressure and tidal volumes were collected from the ventilator, and bursting pressure (BP), AL and AL-reduction were determined.

Results

Per sealant 10 measurements were performed (both experiments). In the first experiment, BP was superior for GATT-Patch Double (60±24 cmH2O) compared to TachoSil® (30±11 cmH2O, P<0.001), Hemopatch® (33±6 cmH2O, P=0.006), Coseal® (25±13 cmH2O, P=0.001) and Progel® (33±11 cmH2O, P=0.005). AL-reduction was superior for GATT-Patch Double (100%±1%) compared to Hemopatch® (46%±50%, P=0.010) and TachoSil® (31%±29%, P<0.001), and also for GATT-Patch Single (100%±14%, P=0.004) and Progel (89%±40%, P=0.027) compared to TachoSil®. In the second experiment, GATT-Patch Single was superior regarding BP (45±10 vs. 40±6 cmH2O, P=0.043) and AL-reduction (100%±11% vs. 68%±40%, P=0.043) when compared to Hemopatch®.

Conclusions

The novel NHS-POx patch shows promise as a lung sealant, demonstrating elevated BP, good adhesive strength and a superior AL-reduction.

Ten-year experience in the clinical management of intralobar pulmonary sequestration in children

OBJECTIVES

Intralobar pulmonary sequestration (ILS) is rare and its optimal clinical management remains ambiguous. This study aimed to introduce our 10-year experience in clinical management of ILS. And the application of our novel surgical method, thoracoscopic anatomical lesion resection (TALR) on ILS was introduced.

MATERIALS AND METHODS

Patients with ILS who received treatment between December 2010 and 2020 were included in this study, retrospectively. A binary logistic regression model was used to assess risk factors for preoperative symptoms. Intraoperative and postoperative outcomes were compared between the thoracoscopic lobectomy and lung-sparing surgery groups.

RESULTS

A total of 112 patients were included in this study. Age and maximum cyst diameter were risk factors for preoperative symptoms. Lung-sparing surgery proved to be safe and feasible with no residual lesions.

CONCLUSIONS

The overall prognosis of early thoracoscopic surgery for ILS was good. Lung-sparing surgery, especially TALR could be used as a first-line surgery for ILS. It may resolve the long-standing controversy over whether surgery for asymptomatic patients with ILS.

Prolonged air leak after robotic lung resection: a narrative review

Background and Objective

Prolonged air leak (PAL) following lung resection is related to an increase in morbidity and both direct and indirect costs. In recent years, robotic-assisted thoracic surgery (RATS) has proved to be a safe technique with comparable perioperative outcomes of video-assisted thoracic surgery (VATS), optimal oncological results, and potential advantages in case of sublobar resection. We here focus on the incidence and clinical impact of PAL in the field of robotic surgery and discuss the therapeutic strategies currently available.

Methods

We conducted a search on PubMed/MEDLINE and Scopus database from inception until May 27^th 2022 to select the relevant literature published in English exploring the occurrence of PAL following RATS.

Key Content and Findings

The implementation of robotic surgery led to a significant reduction in PAL occurrence after pulmonary resection compared to open thoracotomy, while there is still no clear advantage with respect to VATS. However, the enhanced dexterity and improved visualization of the robot seem to particularly valuable in case of sublobar lung resection, especially complex ones. Accurate selection of patients based on the presence of risk factors allows the implementation of intraoperative measures in order to reduce the occurrence of PAL.

Conclusions

Robotic lung resection is a safe technique, advantageous compared to traditional open thoracotomy in terms of PAL occurrence reduction and it is a valid alternative to manual VATS. Moreover, with the extension of indications for sublobar resection in the treatment of early stage lung cancer, RATS may prove to be the technique of choice thanks to its intrinsic advantages.

Pulmonary function changes after sublobar resection in patients with peripheral non-subpleural nodules

Background

In the treatment of peripheral early-staged lung cancer and benign lesions, segmentectomy and wedge resection are both reliable treatment methods. It is debatable that how much pulmonary function will be lost after different sublobar resection in the treatment of early-staged deep-located peripheral NSCLC (non-small cell lung cancer). The purpose of this study was to explore postoperative pulmonary function changes of sublobar resection in enrolled patients with non-subpleural peripheral nodules.

Methods

We collected clinical data of patients undergoing VATS (video-assisted thoracoscopic surgery) segmentectomy or wedge resection for single nodule. These nodules were confirmed as peripheral non-subpleural nodules by preoperative 3D imaging. Patients were divided into two groups according to the operation procedure. Demographic characteristics, pulmonary function, postoperative outcomes, and others were collected. All data was gathered at the First Affiliated Hospital of Soochow University. Outcomes after wedge resection were compared with those after segmentectomy resection.

Results

A total of 88 patients were included in this study, including 46 patients with VATS wedge resection and 42 patients with VATS segmentectomy. No difference was detected when comparing FEV1 (forced expiratory volume in 1 s) loss between these two groups (17.6 ± 2.1%, wedge resection vs. 19.4 ± 5.4%, segmentectomy, P = 0.176). FVC (forced vital capacity) loss (8.7 ± 2.3%, wedge resection vs. 17.1 ± 2.2%, segmentectomy, P < 0.001) and MVV (maximum ventilatory volume) loss (11.5 ± 3.1%, wedge resection vs. 20.6 ± 7.8%, segmentectomy, P < 0.001) in segmentectomy group was significantly higher than those in wedge resection group. Discrepancies were investigated when comparing duration of surgery (70 ± 22 min, wedge resection vs. 111 ± 52 min, segmentectomy, P = 0.0002), postoperative drainage (85 ± 45 mL, wedge resection vs. 287 ± 672 mL, segmentectomy, P = 0.0123), and treatment hospitalization expenses [35148 ± 889CNY, wedge resection vs. 52,502 (38,276–57,772) CNY, segmentectomy, P < 0.0002]. No significant difference was found between air leak time (1.7 ± 0.7 days, wedge resection vs. 2.5 ± 1.7 days, segmentectomy, P = 0.062) and hospitalization time (2.7 ± 0.7 days, wedge resection vs. 3.5 ± 1.7 days, segmentectomy, P = 0.051).

Conclusions

For patients with peripheral non-subpleural nodules, we observed that patients who underwent wedge resection had less lung function loss than those who underwent segmentectomy when their lung function was reviewed at the 6th month after surgery. Patients undergoing wedge resection had partial advantages over patients with segmental resection in terms of hospitalization cost, operation time and postoperative drainage, etc. Wedge resection, as a treatment for peripheral non-subpleural pulmonary nodules, seemed to have more advantages in preserving patients’ pulmonary function.

Construction and validation of a nomogram for predicting prolonged air leak after minimally invasive pulmonary resection

Background

Prolonged air leak (PAL) remains one of the most frequent postoperative complications after pulmonary resection. This study aimed to develop a predictive nomogram to estimate the risk of PAL for individual patients after minimally invasive pulmonary resection.

Methods

Patients who underwent minimally invasive pulmonary resection for either benign or malignant lung tumors between January 2020 and December 2021 were included. All eligible patients were randomly assigned to the training cohort or validation cohort at a 3:1 ratio. Univariate and multivariate logistic regression were performed to identify independent risk factors. All independent risk factors were incorporated to establish a predictive model and nomogram, and a web-based dynamic nomogram was then built based on the logistic regression model. Nomogram discrimination was assessed using the receiver operating characteristic (ROC) curve. The calibration power was evaluated using the Hosmer-Lemeshow test and calibration curves. The nomogram was also evaluated for clinical utility by the decision curve analysis (DCA).

Results

A total of 2213 patients were finally enrolled in this study, among whom, 341 cases (15.4%) were confirmed to have PAL. The following eight independent risk factors were identified through logistic regression: age, body mass index (BMI), smoking history, percentage of the predicted value for forced expiratory volume in 1 second (FEV1% predicted), surgical procedure, surgical range, operation side, operation duration. The area under the ROC curve (AUC) was 0.7315 [95% confidence interval (CI): 0.6979–0.7651] for the training cohort and 0.7325 (95% CI: 0.6743–0.7906) for the validation cohort. The P values of the Hosmer-Lemeshow test were 0.388 and 0.577 for the training and validation cohorts, respectively, with well-fitted calibration curves. The DCA demonstrated that the nomogram was clinically useful. An operation interface on a web page (https://lirongyangql.shinyapps.io/PAL_DynNom/) was built to improve the clinical utility of the nomogram.

Conclusion

The nomogram achieved good predictive performance for PAL after minimally invasive pulmonary resection. Patients at high risk of PAL could be identified using this nomogram, and thus some preventive measures could be adopted in advance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02716-w.

A novel system applying artificial intelligence in the identification of air leak sites

Objective

Prolonged air leak is the most common complication of thoracic surgery. Intraoperative leak site detection is the first step in decreasing the risk of leak-related postoperative complications.

Methods

We retrospectively reviewed the surgical videos of patients who underwent lung resection at our institution. In the training phase, deep learning-based air leak detection software was developed using leak-positive endoscopic images. In the testing phase, a different data set was used to evaluate our proposed application for each predicted box.

Results

A total of 110 originally captured and labeled images obtained from 70 surgeries were preprocessed for the training data set. The testing data set contained 64 leak-positive and 45 leak-negative sites. The testing data set was obtained from 93 operations, including 58 patients in whom an air leak was present and 35 patients in whom an air leak was absent. In the testing phase, our software detected leak sites with a sensitivity and specificity of 81.3% and 68.9%, respectively.

Conclusions

We have successfully developed a deep learning-based leak site detection application, which can be used in deflated lungs. Although the current version is still a prototype with a limited training data set, it is a novel concept of leak detection based entirely on visual information.

Treatment of a pneumatocele in a COVID-19 patient with endobronchial valves

A man in his 40s was admitted to his local hospital 6 days after the first vague symptoms of COVID-19. His general condition deteriorated, and he was treated in the intensive care unit but did not require mechanical ventilation. During his recovery, he experienced a cough spell, after which his dyspnoea recurred and rapidly increased. CT pulmonary angiogram showed a 10×18 cm cavitary lesion with an air-fluid level and surrounding atelectasis of the right lower lobe. A one-way valve mechanism had developed, leading to the formation of a pneumatocele. The patient was treated by occlusion of all bronchial segments of the right lower lobe with endobronchial valves, and the pneumatocele was evacuated with a pigtail catheter. The valves were removed 4 weeks after insertion, and the right lower lobe re-expanded. Six months after treatment, the patient had recovered completely and almost regained his former lung function.

Efficacy of multi-groove silicone drains in single-port video-assisted thoracoscopic lung cancer surgery and their effect on C-reactive protein: a single-center experience

Background

The purpose of this study was to systematically evaluate the effectiveness and safety of a multi-groove silicone drain in single-port video-assisted thoracoscopic lung cancer surgery and its effect on postoperative serum C-reactive protein (CRP) levels.

Methods

We retrospectively analyzed 122 surgical cases who underwent standard lobectomy and lymph node dissection for primary lung cancer between May 2020 and December 2020. A total of 62 patients received 19-F multi-groove silicone drains (experimental group) and 60 patients received 24-F conventional chest drains (control group). According to the different thoracic drainage approaches, the clinical efficacy in the perioperative period, postoperative complications, and postoperative serum CRP levels were compared between the 2 groups.

Results

In this study, thoracic drainage volume, the average visual analog scale (VAS) pain scores in incisions, the rate of primary healing at the site of incisions, and the pulmonary infection rate in the multi-groove silicone drain group were significantly lower than those in the conventional chest drain group (P<0.05), but there was no significant difference in the average hospital stay time, arrhythmia rates, and chest tube removal time between the 2 groups. At postoperative day 1, the levels of serum CRP in the 2 groups were further increased (P>0.05), and the comparison between the 2 groups showed that the levels of serum CRP in the multi-groove silicone drain group at 72 h after the operation were significantly lower than those in the conventional drain group (P<0.05).

Conclusions

Our results showed that a multi-groove silicone drain is feasible and relatively safe in single-port video-assisted thoracoscopic lung cancer surgery for most patients. However we should take cautious in those patients with higher susceptibility of postoperative active bleeding. In patients undergoing lung cancer surgery in the clinical treatment process, the use of a multi-groove silicone drain can improve the quality of life of patients. Due to a small number of included studies and unclear bias, the above results should be verified by high-quality, large-sample randomized controlled studies.

Keywords

Video-assisted thoracoscopic lung cancer surgery; multi-groove silicone drains; conventional chest drains