Preserving the pulmonary vagus nerve branches during thoracoscopic esophagectomy

Persistent cough after pulmonary resection: Minor issue, major hurdle

Background

Persistent cough is one of the most common complications following pulmonary resection, that impairs patients' quality of life and prolongs recovery time. However, a comprehensive review of persistent cough after pulmonary resection (CAP) has not been performed.

Methods

A literature search of PubMed/MEDLINE, Web of Science, and Embase database was conducted for persistent-CAP up to June 2023. Subsequent qualitative systematic review focused on definition, risk factors, prevention, and treatment of persistent-CAP.

Results

Persistent-CAP stands as a prevalent postoperative complication subsequent to pulmonary resection procedures. with an incidence of 24.4-55.0 %. Although persistent-CAP has a minor impact on survival, this condition is of critical importance because it presents a major hurdle in recovery after surgery. In this review, we proposed a systemic definition for persistent-CAP based on available evidence and our own data. Several assessment tools used to assess severity of persistent-CAP are also introduced. Risk factors associated with persistent-CAP are explored, including surgical approaches, resection extent, surgical site, lymph node dissection, postoperative gastroesophageal acid reflux, tracheal intubation anesthesia, preoperative comorbidity, and sex among others. Surgical and anesthesia preventions targeting risk factors to prevent persistent-CAP are elaborated. A number of studies have shown that a multidisciplinary approach can effectively relieve persistent-CAP.

Conclusions

Although the mechanisms underlying persistent-CAP are still unclear, existing studies demonstrated that persistent-CAP is related to surgical and anesthesia factors. Therefore, in the future, prevention and treatment should be developed based on risk factors to overcome the hurdle of persistent-CAP.

Pulmonary vagus nerve transection for chronic cough after video-assisted lobectomy: a randomized controlled trial

BACKGROUND

Chronic cough is common after lobectomy. Vagus nerves are part of the cough reflex. Accordingly, transection of the pulmonary branches of vagus nerve may prevent chronic cough. And there are no clear recommendations on the management of the pulmonary branches of vagus in any thoracic surgery guidelines.

METHODS

This is a single-center, randomized controlled trial. Adult patients undergoing elective video-assisted thoracoscopic lobectomy and lymphadenectomy were randomized at a 1:1 ratio to undergo a sham procedure (control group) or transection of the pulmonary branches of the vagus nerve that innervate the bronchial stump plus the caudal-most large pulmonary branch of the vagus nerve. The primary outcome was the rate of chronic cough, as assessed at 3 months after surgery in the intent-to-treat population.

RESULTS

Between 1 February 2020 and 1 August 2020, 116 patients (59.6±10.1 years of age; 45 men) were randomized (58 in each group). All patients received designated intervention. The rate of chronic cough at 3 months was 19.0% (11/58) in the vagotomy group versus 41.4% (24/58) in the control group (OR=0.332, 95% CI: 0.143-0.767; P =0.009). In the 108 patients with 2-year assessment, the rate of persistent cough was 12.7% (7/55) in the control and 1.9% (1/53) in the vagotomy group ( P =0.032). The two groups did not differ in postoperative complications and key measures of pulmonary function, for example, maximal voluntary ventilation, diffusing capacity of the lungs for carbon monoxide, and forced expiratory volume.

CONCLUSION

Transecting the pulmonary branches of vagus nerve that innervate the bronchial stump plus the caudal-most large pulmonary branch decreased the rate of chronic cough without affecting pulmonary function in patients undergoing video-assisted lobectomy and lymphadenectomy.

Preservation of the pulmonary branches of the vagus nerve during three-dimensional thoracoscopic radical resection of lung cancer: a retrospective study

BACKGROUND

In this study, we investigated the effect of preservation of the pulmonary branches of the vagus nerve during systematic dissection of mediastinal lymph nodes, when performing radical resection of lung cancer, on the postoperative complication rate.

METHODS

The clinical data for 80 patients who underwent three-dimensional thoracoscopic radical resection of lung cancer in the Department of Thoracic Surgery at Huizhou Municipal Central Hospital between 2020 and 2022 were analyzed. The patients were divided into two groups according to whether the pulmonary branches of the vagus nerve were retained during intraoperative carinal lymph node dissection. The operation time, time until first postoperative defecation, duration for which a chest tube was needed, total chest drainage volume, average pain intensity during the first 5 postoperative days, incidence of postoperative pneumonia, and postoperative length of stay were compared between the two groups.

RESULTS

There was no statistically significant difference in histological staging or in time until first postoperative defecation between the two groups (p > 0.05). However, there were significant differences in operation time, the duration for which a chest tube was needed, total chest drainage volume, average pain intensity during the first 5 postoperative days, white blood cell count and procalcitonin level on postoperative days 1 and 5, and postoperative length of stay between the two groups (p < 0.05).

CONCLUSION

Preserving the pulmonary branches of the vagus nerve during carinal lymph node dissection when performing three-dimensional thoracoscopic radical resection of lung cancer can reduce the risk of postoperative complications.

A Comparison of Two Methods of Pre-operative Inspiratory Muscle Training on Post-operative Outcome Following Esophagectomy

Esophageal carcinoma is a multifaceted and complex disease of rapidly rising incidence that exerts an increasing social and financial burden on global healthcare systems. Esophagectomy is associated with high rates of peri- and post-operative morbidity and mortality because of complex anatomy, frail health of patients, and late diagnosis of the disease. The most common complication seen is post-operative pulmonary complication (PPC). This study was planned to compare and analyze the outcome of two different protocols of preoperative IMT program on the rate of PPCs in patients undergoing esophagectomy. Twenty patients who underwent esophagectomy for carcinoma esophagus were included in the study and were randomly divided into 2 groups of 10 each. Group A received IMT-HI training for 4 weeks, whereas the group B received IMT-E training for 4 weeks pre-operatively. All the patients included in the study underwent a baseline pulmonary assessment which included pulmonary function test (FVC, FEV1, and FEV1/FVC), maximum inspiratory pressure (MIP), and maximum expiratory pressure (MEP). Four-week preoperative IMT-HI lead to better outcome following esophagectomy as compared to IMT-E. Relative risk of PPC was 4:1 (IMT-E:IMT-HI). However, there was no statistically significant improvement in PFTs, MEP, and MIP from baseline or between two groups. The difference in PPC in two groups did not reach statistical significance despite the fact that relative risk of PPC was 4:1 (IMT-E:IMT-HI).

Exploring the Modulatory Effect of High-Fat Nutrition on Lipopolysaccharide-Induced Acute Lung Injury in Vagotomized Rats and the Role of the Vagus Nerve

During esophagectomy, the vagus nerve is transected, which may add to the development of postoperative complications. The vagus nerve has been shown to attenuate inflammation and can be activated by a high-fat nutrition via the release of acetylcholine. This binds to α7 nicotinic acetylcholine receptors (α7nAChR) and inhibits α7nAChR-expressing inflammatory cells. This study investigates the role of the vagus nerve and the effect of high-fat nutrition on lipopolysaccharide (LPS)-induced lung injury in rats. Firstly, 48 rats were randomized in 4 groups as follows: sham (sparing vagus nerve), abdominal (selective) vagotomy, cervical vagotomy and cervical vagotomy with an α7nAChR-agonist. Secondly, 24 rats were randomized in 3 groups as follows: sham, sham with an α7nAChR-antagonist and cervical vagotomy with an α7nAChR-antagonist. Finally, 24 rats were randomized in 3 groups as follows: fasting, high-fat nutrition before sham and high-fat nutrition before selective vagotomy. Abdominal (selective) vagotomy did not impact histopathological lung injury (LIS) compared with the control (sham) group (p > 0.999). There was a trend in aggravation of LIS after cervical vagotomy (p = 0.051), even after an α7nAChR-agonist (p = 0.090). Cervical vagotomy with an α7nAChR-antagonist aggravated lung injury (p = 0.004). Furthermore, cervical vagotomy increased macrophages in bronchoalveolar lavage (BAL) fluid and negatively impacted pulmonary function. Other inflammatory cells, TNF-α and IL-6, in the BALF and serum were unaffected. High-fat nutrition reduced LIS after sham (p = 0.012) and selective vagotomy (p = 0.002) compared to fasting. vagotomy. This study underlines the role of the vagus nerve in lung injury and shows that vagus nerve stimulation using high-fat nutrition is effective in reducing lung injury, even after selective vagotomy.

Application of Vagus Nerve Branch Preservation in Thoracoscopic Surgery for Early-Stage Lung Cancer

Background. In this study, we introduced a novel surgical strategy to protect vagal nerve branches during radical thoracoscopic surgery in right lung cancer and explored the effects of vagal nerve branch preservation. Methods. We retrospectively studied 53 patients with right-sided lung cancer with clinically staged T1N0M0 between 2019 and 2020. All 53 patients were treated with total thoracoscopic lobectomy and mediastinal lymph node dissection in the same number of lymph node stations. Of these, 22 patients adopted a vagus nerve branch protection strategy during lymph node dissection. Another 31 patients were treated with traditional lymph node dissection as the control group. Results. The characteristics of the patients were similar between the two groups. The operation time and intraoperative bleeding in the protection group were longer than those in the control group. However, the protection group had a lower average postoperative pain score and average postoperative hospital stay. The above difference was not statistically significant. Three cases of arrhythmia occurred in the protection group, including 1 case of tachycardia and 2 cases of atrial fibrillation. In the control group, 13 cases of arrhythmia occurred after the operation, including 8 cases of tachycardia and 5 cases of atrial fibrillation. We also tracked changes in the patients’ heart rates throughout the treatment process (excluding patients with arrhythmias). An increased heart rate was observed postoperatively in both groups, but the increase of heart rate of the protection group was smaller than that of the control group; however, the difference was not statistically significant. Conclusions. A vagus nerve branch preservation-based approach to radical surgery is a safe and feasible strategy for right lung cancer treatment, which could significantly reduce the risk of postoperative arrhythmia in patients and may also have a potential role in reducing the length of hospital stay and maintaining heart rate stability in the postoperative period.

Perioperative safety and short-term efficacy of functional minimally invasive esophagectomy

Background

Standard minimally invasive McKeown three-field esophagectomy (SMIE) results in high perioperative risk and poor postoperative quality of life owing to considerable surgical damage and numerous postoperative complications. We created a modified procedure, functional minimally invasive esophagectomy (FMIE), which preserves the azygos arch, bronchial artery, pulmonary branch of the vagus nerve, and the mediastinal pleura. Our aim was to evaluate the efficacy and safety of FMIE and to determine whether it has limited invasiveness.

Methods

Between 2018 and 2020, FMIE was performed for 48 patients who were compared with 76 SMIE cases; 44 paired cases were matched using propensity score matching.

Results

Operation time, extubation time, and postoperative hospital stay were significantly lower in the FMIE group. FMIE was also associated with fewer pulmonary infections. Postoperative drainage volume on postoperative day (POD) 1 and POD 2, and white blood cell counts on POD 2 and POD 4 were also significantly lower in the FMIE group. There was no statistically significant difference in the number of dissected lymph nodes, short-term recurrence, metastasis rates, or survival rate between the two groups.

Conclusions

FMIE is a less invasive procedure and may be a suitable alternative for lower and early middle esophageal carcinoma.

[Initial experience of robot-assisted minimally invasive McKeown esophagectomy]

OBJECTIVE

To report our initial experience of robot-assisted McKeown esophagectomy with stapled cervical esophagogastrostomy.

MATERIAL AND METHODS

There were 5 robot-assisted McKeown esophagectomies in patients with benign end-staged and malignant diseases of the esophagus for the period from October 2019 to February 2020.

RESULTS

No conversions and intraoperative complications were observed. Mean surgery time was 406±48 min, total intraoperative blood loss - 108±45 ml. Four patients had minor complications (wound infection, atelectasis, pneumothorax) that required conservative treatment. We have controlled anastomosis in 2-3 postoperative days with water-soluble contrast, none patient had an anastomotic leakage. Mean hospital-stay was 5 days. Complete (R0) resection was accomplished in all patients with malignant neoplasms.

CONCLUSIONS

Our first experience showed that robot-assisted McKeown esophagectomy is a safe and feasible surgical option for esophageal diseases. Robot-assisted interventions require advanced endoscopic surgical experience.

Minimally Invasive Esophagectomy for Achieving R0

BACKGROUND

Minimally invasive esophagectomy (MIE) is becoming increasing popular. Since it was introduced, there has been debate about its safety and efficacy when compared with open esophagectomies (OE). We sought to compare the oncologic outcomes of MIE and OE in this study specifically with regards to margin status and nodal retrieval.

METHODS

Ninety-three patients that underwent MIE (76/93) or OE (17/93) for esophageal cancer at out institution between January 2013 and September 2018 were retrospectively reviewed. Histological type, pathological tumor grading, clinical tumor staging (cTNM), pathological tumor staging (pTNM), post-neoadjuvant tumor staging (ypTNM), and lymph node retrieval were obtained and compared.

RESULTS

The results show a statistically significant improvement in resection margins (R0) in the MIE group when compared with the OE group. Other oncologic parameters including clinical staging, pathologic staging, tumor grade, neoadjuvant therapy (NAT), and nodal retrieval were not statistically significantly different between the open and MIE groups.

CONCLUSION

The improvement in short-term surgical outcomes in MIE is well established. This study demonstrates that MIE can have superior surgical oncologic outcomes compared to OE, this was specifically an improved R0 margin rate with MIE compared to OE. These results further support the use of MIE in the treatment of esophageal cancer.

Early Respiratory Impairment and Pneumonia after Hybrid Laparoscopically Assisted Esophagectomy-A Comparison with the Open Approach

Patients undergoing esophageal cancer surgery are at high risk of developing severe pulmonary complications. Beneficial effects of minimally invasive esophagectomy had been discussed recently, but the incidence of perioperative respiratory impairment remains unclear. This is a retrospective single-center cohort study of patients, who underwent open (OE) or laparoscopically assisted, hybrid minimally invasive abdomino-thoracic esophagectomy (LAE) for cancer regarding respiratory impairment (PaO₂/FiO₂ ratio (P/FR) < 300 mmHg) and pneumonia. No differences were observed in the cumulative incidence of reduced P/FR between OE and LAE patients. Of note, until postoperative day (POD) 2, P/FR did not differ among both groups. Thereafter, the rate of patients with respiratory impairment was higher after OE on POD 3, 5, and 10 (p ≤ 0.05) and tended being higher on POD 7 and 9 (p ≤ 0.1). Although the duration of LAE procedure was slightly longer (total: p = 0.07, thoracic part: p = 0.004), the duration of surgery (Spearman's rank correlation coefficient (r_sp) = -0.267, p = 0.006), especially of laparotomy (r_sp = -0.242, p = 0.01) correlated inversely with respiratory impairment on POD 3 after OE. Pneumonia occurred on POD 5 (1-25) and 8.5 (3-14) after OE and LAE, respectively, with the highest incidence after OE (p = 0.01). In conclusion, respiratory impairment and pulmonary complications occur frequently after esophagectomy. Although early respiratory impairment is independent of the surgical approach, postoperative pneumonia rate is reduced after LAE.

Robotic-assisted minimally invasive esophagectomy: past, present and future

Esophagectomy for cancer of the esophagus is increasingly performed using minimally invasive techniques. After the introduction of minimally invasive esophagectomy (MIE) in the early 1990's, robotic-assisted techniques followed after the turn of the millennium. The advent of robotic platforms has allowed the development of robotic-assisted minimally invasive esophagectomy (RAMIE) over the past 15 years. Although recent trials have shown superior peri-operative morbidity and quality of life compared to open esophagectomy, no randomized trials have compared RAMIE to conventional MIE. This paper summarizes the current literature on RAMIE and provides an overview of expected future developments in robotic surgery.

Ivor Lewis esophagectomy patients are particularly vulnerable to respiratory impairment - a comparison to major lung resection

Pulmonary complications and a poor clinical outcome are common in response to transthoracic esophagectomy, but their etiology is not well understood. Clinical observation suggests that patients undergoing pulmonary resection, a surgical intervention with similarities to the thoracic part of esophagectomy, fare much better, but this has not been investigated in detail. A retrospective single-center analysis of 181 consecutive patients after right-sided thoracotomy for either Ivor Lewis esophagectomy (n = 83) or major pulmonary resection (n = 98) was performed. An oxygenation index <300 mm Hg was used to indicate respiratory impairment. When starting surgery, respiratory impairment was seen more frequently in patients undergoing major pulmonary resection compared to esophagectomy patients (p = 0.009). On postoperative days one to ten, however, esophagectomy caused higher rates of respiratory impairment (p < 0.05) resulting in a higher cumulative incidence of postoperative respiratory impairment for patients after esophagectomy (p < 0.001). Accordingly, esophagectomy patients were characterized by longer ventilation times (p < 0.0001), intensive care unit and total postoperative hospital stays (both p < 0.0001). In conclusion, the postoperative clinical course including respiratory impairment after Ivor Lewis esophagectomy is significantly worse than that after major pulmonary resection. A detailed investigation of the underlying causes is required to improve the outcome of esophagectomy.

The clinical value of a new method of functional lymph node dissection in video-assisted thoracic surgery right non-small cell lung cancer radical resection

Background

To evaluate the safety, thoroughness and feasibility of "tunnel-type en bloc mediastinal lymph node dissection" in video-assisted thoracic surgery (VATS) for right non-small cell lung cancer (NSCLC) radical resection, which functionally dissected the lymph nodes of station 2R/4R/7.

Methods

A retrospective study was performed in the clinical data of 196 patients with VATS right NSCLC radical resection. According to the different methods of lymph node dissection of station 2R, 4R and 7, they were divided into the tunnel-type group (n=102) and the routine group (n=94). The clinical data of two group were compared.

Results

The analyses of the baselines of the two groups are comparable. For lymph nodes dissection of station 2R/4R/7, operation time, the total number, positive number and metastasis incidence shown no significant difference between two groups (P>0.05). However, the amount of bleeding, postoperative thoracic drainage volume, extubation time, hospitalization days, the incidence of postoperative pulmonary infection and chronic cough were significantly lower in the tunnel-type group (P<0.05). There was no significant difference in 3-year recurrence and metastasis and in 3-year survival between tunnel-type group and routine group.

Conclusions

The tunnel-type group has more advantages, such as less surgical trauma, shorter hospitalization time, faster postoperative rehabilitation, even less postoperative chronic cough compared with the routine group. Therefore, we believe that the tunnel-type en bloc mediastinal lymph node dissection is a safe, thorough and feasible surgical method, which is worthy of being popularized and applied in the VATS right NSCLC radical resection.

Multicentre randomized clinical trial of inspiratory muscle training versus usual care before surgery for oesophageal cancer

Background

Up to 40 per cent of patients undergoing oesophagectomy develop pneumonia. The aim of this study was to assess whether preoperative inspiratory muscle training (IMT) reduces the rate of pneumonia after oesophagectomy.

Methods

Patients with oesophageal cancer were randomized to a home-based IMT programme before surgery or usual care. IMT included the use of a flow-resistive inspiratory loading device, and patients were instructed to train twice a day at high intensity (more than 60 per cent of maximum inspiratory muscle strength) for 2 weeks or longer until surgery. The primary outcome was postoperative pneumonia; secondary outcomes were inspiratory muscle function, lung function, postoperative complications, duration of mechanical ventilation, length of hospital stay and physical functioning.

Results

Postoperative pneumonia was diagnosed in 47 (39·2 per cent) of 120 patients in the IMT group and in 43 (35·5 per cent) of 121 patients in the control group (relative risk 1·10, 95 per cent c.i. 0·79 to 1·53; P = 0·561). There was no statistically significant difference in postoperative outcomes between the groups. Mean(s.d.) maximal inspiratory muscle strength increased from 76·2(26·4) to 89·0(29·4) cmH2O (P &lt; 0·001) in the intervention group and from 74·0(30·2) to 80·0(30·1) cmH2O in the control group (P &lt; 0·001). Preoperative inspiratory muscle endurance increased from 4 min 14 s to 7 min 17 s in the intervention group (P &lt; 0·001) and from 4 min 20 s to 5 min 5 s in the control group (P = 0·007). The increases were highest in the intervention group (P &lt; 0·050).

Conclusion

Despite an increase in preoperative inspiratory muscle function, home-based preoperative IMT did not lead to a decreased rate of pneumonia after oesophagectomy. Registration number: NCT01893008 (https://www.clinicaltrials.gov).

Robot-assisted minimally invasive esophagectomy

Esophagolymphadenectomy is the cornerstone of multimodality treatment for resectable esophageal cancer. The preferred surgical approach is transthoracic, with a two-field lymph node dissection and gastric conduit reconstruction. A minimally invasive approach has been shown to reduce postoperative complications and increase quality of life. Robot-assisted minimally invasive esophagectomy (RAMIE) was developed to facilitate this complex thoracoscopic procedure. RAMIE has been shown to be safe with good oncologic results and reduced morbidity. The use of RAMIE opens new indications for curative surgery in patients with T4b tumors, high mediastinal tumors, and lymph node metastases after neoadjuvant treatment.

[Robot-assisted minimally invasive esophagectomy. German version]

Esophagolymphadenectomy is the cornerstone of multimodality treatment for resectable esophageal cancer. The preferred surgical approach is transthoracic, with a two-field lymph node dissection and gastric conduit reconstruction. A minimally invasive approach has been shown to reduce postoperative complications and increase quality of life. Robot-assisted minimally invasive esophagectomy (RAMIE) was developed to facilitate this complex thoracoscopic procedure. RAMIE has been shown to be safe with good oncologic results and reduced morbidity. The use of RAMIE opens new indications for curative surgery in patients with T4b tumors, high mediastinal tumors, and lymph node metastases after neoadjuvant treatment.

New insights into the surgical anatomy of the esophagus

Implementation of (robot assisted) minimally invasive esophagectomy and increased knowledge of the relation between the autonomic nervous system and the immune response have led to new insights regarding the surgical anatomy of the esophagus. First, two layers of connective tissue were identified; the aorto-esophageal and aorto-pleural ligaments that separate the peri-esophageal compartment, containing vagus nerves, carinal lymph nodes and trachea, from the para-aortic compartment; containing thoracic duct and azygos vein. Second the surgical anatomy of the pulmonary vagus nerve branches has been described in detail. Based on the hypothesis that sparing the vagal nerve branches may be important a method to spare the pulmonary branches of the vagus nerve during thoracoscopic esophagectomy was validated in a cadaver study. Further studies will now investigate the impact of these new insights in the surgical anatomy of the esophagus in clinical practice.

Video-assisted thoracoscopic esophagectomy: keynote lecture

Minimally invasive esophagectomy (MIE) by thoracoscopy after neoadjuvant therapy results in significant short-term advantages such as a lower incidence of pulmonary infections and a better quality of life (QoL) with the same completeness of resection. After 1 year, a better QoL is still observed for MIE in comparison with the open approach, while having the same survival. Seven issues about implementation of MIE for cancer require discussion: (1) choice of the extension of esophageal resection and use of neoadjuvant therapy; (2) reasons to approach the esophageal cancer by MIE; (3) determining the best minimally invasive approach for gastro-esophageal junction cancers; (4) implementation of evidence-based MIE; (5) standardization of the surgical anatomy of the esophagus based on MIE; (6) future lines of research of MIE; and (7) learning process. In the time of imaging-integrated surgery it is clear that the MIE approach should be increasingly implemented in all centers worldwide having an adequate volume of patients and expertise.