Perspectives and horizons of non-intubated robotic-assisted tracheal surgery

Tracheal surgery remains a field of complex interdisciplinary collaboration given proximity of surgical site and anesthetic working space. Multitude medical advances aimed to reduce hurdles in ventilation during resection resulting in established intubation and ventilation techniques reaching from general anesthesia with small-sized endotracheal tube with or without lung separation, jet-ventilation or apneic oxygenation, over spontaneous ventilation under mild sedation even to extracorporeal life support (1). In a similar way, surgical management experienced relevant paradigm shift: while lower parts of trachea were traditionally reached via sternotomy or thoracotomy, current endeavors established video-assisted thoracic surgery (VATS) or even robotic-assisted thoracic surgery (RATS) as suitable techniques for resection.

Recently published article combines both progresses made in anesthetic and surgical management by presenting a case series of tracheal resections under spontaneous ventilation via RATS (2). The authors have made groundbreaking work by proving this combination as feasible in tracheal surgery.

Generally, maximum extent of tracheal resection is recognized as 4 or 6 cm when applying mobilization strategies such as bilateral hilar or suprahyoid laryngeal release, opening of the pleural spaces, and division of the inferior pulmonary ligaments (3,4). This may be a drawback of minimally invasive approaches allowing for unilateral maneuvers only (5). Li et al. described cases of 1.2 cm resections in average with a maximum length of 4.3 cm (2). In consequence, copious release was not necessary. Other case reports of tracheal resections via RATS as well describe resection lengths of less than 3 cm (6,7). The need for extensive bilateral mobilizations strategies may be a limitation criterion for RATS in tracheal surgery. However, compared to VATS techniques, the 3D visualization as well as the facilitation of 7 degrees of freedom, RATS opens up for increased accuracy and handleability of minimal-invasive tracheal surgery (8).

Previous work of the authors has described multiple benefits from spontaneous ventilation regarding easier surgical practicability of tracheal resection and anastomosis as well as more stable hemodynamic status and blood oxygen saturation (9-11). However, hypercapnia is one of the most relevant risks of spontaneous ventilation for thoracic surgery (1). End-tidal CO₂ was reported in one publication only, ranging from 40 and 48 mmHg without respiratory acidosis (9). Yet, information on measurement method and end-tidal CO₂ might be relevant in the current publication as well, since values might be distorted for various reasons such as suction and pneumothorax. Duration of resection might have a significant influence on acid-base balance as well. Hence, information on accurate resection time and whether or how end-tidal CO₂ changed during this period would be interesting as well.

Though Li et al. presented a novel and impressive series of cases one must acknowledge that it cannot serve as robust data basis for widespread use and may only be practicable in high-volume centers of this seldom disease. Surgical experience based on solitary cases or small series only does not meet modern standards of evidence-based medicine and should not be appropriate anymore. Fundamental and comprehensive upheaval of operative techniques must be built upon solid scientific data from prospective randomized multicenter clinical trials.

Acknowledgments

Funding: None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Annals of Translational Medicine. The article did not undergo external peer review.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://dx.doi.org/10.21037/atm-21-4683). SK reports that as part of an educational concept series initiated by Merck (KGaA, Darmstadt, Germany). He received a solitary payment for a lecture about surgical options in the treatment of NSCLC & lung metastasis, outside the submitted work. The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Smeltz AM, Bhatia M, Arora H, et al. Anesthesia for resection and reconstruction of the trachea and carina. J Cardiothorac Vasc Anesth 2020;34:1902-13. [Crossref] [PubMed]
2. Li S, Ai Q, Liang H, et al. Non-intubated robotic-assisted thoracic surgery for tracheal/airway resection and reconstruction: technique description and preliminary results. Ann Surg 2021; Epub ahead of print. [Crossref] [PubMed]
3. Blasberg JD, Wright CD. Surgical considerations in tracheal and carinal resection. Semin Cardiothorac Vasc Anesth 2012;16:190-5. [Crossref] [PubMed]
4. Wright CD, Grillo HC, Wain JC, et al. Anastomotic complications after tracheal resection: prognostic factors and management. J Thorac Cardiovasc Surg 2004;128:731-9. [Crossref] [PubMed]
5. Lazar JF. Confronting the fundamental challenges of airway surgery: a paradigm shift is practically upon us. J Thorac Dis 2017;9:3670-1. [Crossref] [PubMed]
6. Jiao W, Zhao Y, Luo Y, et al. Totally robotic-assisted non-circumferential tracheal resection and anastomosis for leiomyoma in an elderly female. J Thorac Dis 2015;7:1857-60. [PubMed]
7. Hu D, Wang Z, Tantai J, et al. Robotic-assisted thoracoscopic resection and reconstruction of the carina. Interact Cardiovasc Thorac Surg 2020;31:912-4. [Crossref] [PubMed]
8. Lazar JF, Posner DH, Palka W, et al. Robotically assisted bilateral bronchoplasty for tracheobronchomalacia. Innovations (Phila) 2015;10:428-30. [Crossref] [PubMed]
9. Li S, Liu J, He J, et al. Video-assisted transthoracic surgery resection of a tracheal mass and reconstruction of trachea under non-intubated anesthesia with spontaneous breathing. J Thorac Dis 2016;8:575-85. [Crossref] [PubMed]
10. Liu J, Li S, Shen J, et al. Non-intubated resection and reconstruction of trachea for the treatment of a mass in the upper trachea. J Thorac Dis 2016;8:594-9. [Crossref] [PubMed]
11. Peng G, Cui F, Ang KL, et al. Non-intubated combined with video-assisted thoracoscopic in carinal reconstruction. J Thorac Dis 2016;8:586-93. [Crossref] [PubMed]