Non-assistant help operation in dual-portal RATS (neoDRATS): a surgical technique

Introduction

In Japan, recent advances in medical devices, together with the accumulation of oncological evidence (1), have promoted a shift toward less invasive surgical approaches in the field of thoracic surgery. Reduced-port surgery (RPS) has therefore gained increasing attention. Surgical approaches have evolved from conventional thoracotomy to video-assisted thoracic surgery (VATS), and since 2018, robot-assisted thoracic surgery (RATS) has been introduced, resulting in a wide variety of surgical techniques currently in use.

The first robotic surgical procedure was reported by Cadiere et al. in 1999 for bariatric surgery (2). With regard to pulmonary resection, Melfi et al. first reported robotic thoracic surgery in 2002 (3), followed by subsequent reports by Cerfolio (4), Dylewski (5), and others describing various surgical approaches and perioperative outcomes (6). However, from the initial introduction of RATS until recent years, most procedures were performed using a five-port configuration (7). Consequently, this approach may have appeared unfamiliar to Japanese thoracic surgeons, who had traditionally performed VATS using three or four ports.

In this context, as a form of reduced-port RATS (RPRATS), Gonzalez-Rivas and colleagues introduced uniportal RATS and reported clinical comparisons with multiport RATS (8-10). However, in current robotic systems, uniportal RATS presents several technical challenges. Robotic instruments and cameras have a diameter of 8 mm, which is larger than those used in conventional VATS, and robotic staplers are also bulkier. As a result, instrument interference is more likely to occur, making the procedure particularly challenging in patients with smaller physiques, such as many Asian patients.

To overcome these limitations, we conceived and developed a dual-portal robotic-assisted thoracic surgery (DRATS) approach, consisting of a 4-cm main incision with the addition of a single accessory port (11). Furthermore, in conventional RPRATS, one robotic arm is typically canceled, and lung retraction as well as stapling of vessels, bronchi, and fissures are performed by a bedside assistant. In contrast, we further advanced DRATS by utilizing all four robotic arms without canceling any arm, thereby enabling lung retraction and stapler manipulation to be performed primarily from the console. This approach, termed non-assistant help operation in dual-portal RATS (neoDRATS), was subsequently developed (12).

This technique is applicable to a wide range of patients requiring anatomical pulmonary resections, including lobectomy for primary lung cancer. In our practice, neoDRATS is used as a primary approach whenever feasible. In contrast to many reduced-port RATS techniques that require cancellation of one robotic arm and rely on a bedside assistant, neoDRATS enables full utilization of all four robotic arms, allowing console-surgeon-driven lung retraction and robotic stapling. Therefore, this approach can be applied to most anatomical pulmonary resections while maintaining procedural flexibility. When arm interference or technical limitations are encountered, the procedure can be readily converted to conventional DRATS by canceling one robotic arm, thereby ensuring procedural safety.

In this article, we focus on the surgical technique of neoDRATS and provide a detailed description of port placement, robotic arm configuration, utilization of the third arm, and robotic stapling techniques, accompanied by actual operative videos.

The key steps of this technique are demonstrated in the accompanying videos: setup of left-sided neoDRATS (Video 1), neoDRATS left lower lobectomy (Video 2), and neoDRATS right upper lobectomy (Video 3). Additional videos demonstrating neoDRATS procedures for other lobes are available on the author’s YouTube channel (13). We present this article in accordance with the SUPER reporting checklist (available at https://jovs.amegroups.com/article/view/10.21037/jovs-2025-1-61/rc).

Preoperative preparations and requirements

This study was approved by the institutional review board of Tokyo Metropolitan Bokutoh Hospital (No. 05-030) and was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient for the publication of this study, accompanying images and the videos. A copy of the written consent is available for review by the editorial office of this journal.

This procedure is performed as RATS using the da Vinci Xi^® Surgical System (Intuitive Surgical, Sunnyvale, CA, USA) in the operating room under general anesthesia with single-lung ventilation.

All patients undergo standard preoperative evaluations, including assessment of general condition and pulmonary function tests, to confirm that they are suitable candidates for RATS.

Because this technique utilizes the da Vinci Xi system, the surgeon is required to have sufficient training and experience with the system. In addition, a bedside assistant is assigned to manage robotic arm exchanges, sutures, hemostatic materials, and auxiliary instruments. In particular, the presence of an assistant experienced in uniportal VATS is desirable.

Step-by-step description

The key steps of this procedure are demonstrated in Videos 1-3.

Patient positioning and port placement

The patient is placed in the lateral decubitus position with the ipsilateral arm elevated. The pelvis and thorax are aligned in a parallel orientation. Excessive trunk flexion (so-called “jackknife” positioning) is avoided, and only mild trunk flexion of approximately 10 degrees (FLEX 10°) is applied (Figure 1A). A 4-cm skin incision is created at the fifth intercostal space along the mid-axillary line, and a wound protector is placed to establish the main port. The thoracic cavity is inspected, and pleural adhesions, if present, are released as much as possible at this stage. Subsequently, a secondary 1.8-cm skin incision is added at the seventh intercostal space—along the anterior axillary line for upper or middle lobectomy, or along the mid-axillary line for lower lobectomy—and a wound protector is similarly placed to create the secondary port (Figure 1B).

Figure 1 Patient positioning and incision sites. (A) The patient is placed in the lateral decubitus position with the ipsilateral arm elevated. Mild trunk flexion (approximately 10 degrees) is applied while avoiding excessive lateral bending. (B) Incision sites. A 4-cm main incision is created at the fifth intercostal space along the mid-axillary line, and a secondary incision is placed at the seventh intercostal space, either along the anterior axillary line (for upper and middle lobectomies) or along the mid-axillary line (for lower lobectomies). The images were published with the patient’s consent.

Docking and arm configuration

The patient cart can be docked from either the ventral or dorsal side of the patient; however, in this technique, the boom is rotated toward the dorsal side, allowing the bedside assistant to stand on the ventral side. The pointing laser is positioned at the dorsosuperior aspect of the main port, with the laser axis aligned along the intercostal direction. Docking is performed without intrathoracic targeting or use of the remote center function. This approach simplifies the setup and allows flexible alignment of the robotic arms along the intercostal space, facilitating smoother instrument manipulation in dual-portal surgery. In addition, when arm interference occurs, the configuration of the robotic arms can be adjusted as needed to maintain optimal working conditions. Furthermore, carbon dioxide (CO₂) insufflation is not routinely used, not only in consideration of environmental impact and medical cost containment, but also because an adequate operative field can be obtained without insufflation using a fifth intercostal space-based approach. In addition, visualization is not significantly compromised without CO₂ insufflation. Moreover, CO₂ insufflation is not routinely used in most thoracic surgical procedures, such as uniportal VATS, multiport VATS, and thoracotomy. Furthermore, the use of sealed ports may restrict the movement of the bedside assistant and robotic arms, which is not compatible with the concept of this technique. In the absence of CO₂ insufflation, the surgical field was established using long curved suction forceps and cotton-mounted forceps (Delta forceps^®; Sugai Corporation, Japan), assisted by the bedside assistant. A 0-degree camera is used as the default. Use of a 0-degree camera brings the camera axis closer to vertical, thereby improving maneuverability for the bedside assistant. Arm configurations differ between right- and left-sided procedures, as shown in Figures 2,3. The following describes the general port arrangement within the main incision. Within the main incision, three robotic ports are inserted through a wound retractor without intentional vertical staggering. The camera is positioned most superficially, while the right- and left-hand instruments are arranged in an inferior and superior relationship, respectively. Instrument collision is avoided primarily through dynamic console-controlled manipulation rather than fixed vertical port separation.

Figure 2 Arm configuration for right-sided neoDRATS. (A) Overall arm setup for right-sided surgery. (B) Detailed arm configuration. Arm 1 is assigned as the retraction arm and introduced through the secondary port, while Arms 2, 3, and 4 are introduced through the main port. The right-hand and left-hand instruments are arranged to cross within the thoracic cavity to minimize external and internal arm interference. (C) Incision sites for right-sided surgery. Circled numbers indicate robotic arm numbers [1–4]. neoDRATS, non-assistant help dual-portal robotic-assisted thoracic surgery.

Figure 3 Arm configuration for left-sided neoDRATS. (A) Overall arm setup for left-sided surgery. (B) Detailed arm configuration. Arms 1, 2, and 3 are introduced through the main port, and Arm 4 is assigned as the retraction arm and introduced through the secondary port. The camera axis is aligned with the pointing laser, and sufficient clearance is maintained between arms to reduce interference. (C) Incision sites for left-sided surgery. Circled numbers indicate robotic arm numbers [1–4]. neoDRATS, non-assistant help dual-portal robotic-assisted thoracic surgery.

For right-sided surgery, Arm 1 is assigned as the left-hand retraction arm and introduced through the secondary port. Arms 2, 3, and 4 are assigned to the right-hand instrument, camera, and left-hand instrument, respectively, and are introduced through the main port. Within the main port, the right- and left-hand instruments are arranged to cross inside the thoracic cavity to minimize arm interference.

For left-sided surgery, Arm 1 is assigned to the right-hand instrument, Arm 2 to the camera, and Arm 3 to the left-hand instrument, all introduced through the main port. Arm 4 is assigned as the right-hand retraction arm and introduced through the secondary port. To reduce interference, the camera axis is aligned with the pointing laser, and sufficient clearance is maintained between the arms. Formation of a triangular configuration within the main port and between the main and secondary ports facilitates smooth instrument manipulation. After completion of the setup, the procedure is performed in a stepwise manner following standard thoracic surgical principles. Hilar dissection is initiated under stable exposure, and the pulmonary vessels and bronchus are sequentially identified, dissected, and divided using robotic instruments. Lymph node dissection is then performed as appropriate. Throughout the procedure, stable exposure and safety are maintained through coordinated use of the robotic arms and flexible conversion strategies when necessary.

Use of energy devices and staplers

Energy devices are selected according to the surgeon’s preference. In this technique, SynchroSeal is used as the right-hand instrument through the main port, primarily in bipolar mode. For delicate dissection, such as around lymph nodes, a Maryland bipolar forceps is used. The pulmonary artery and pulmonary vein are generally divided using SureForm staplers. For small vessels, the proximal side is secured with clips or ligation, and the distal side is divided using SynchroSeal. Staplers are typically introduced through the retraction arm via the secondary port. The recently available SureForm 30 Curved-tip stapler has a slimmer shaft and improved intrathoracic maneuverability, allowing its use through the main port in selected cases.

Roll-out and chest tube placement

After completion of pulmonary resection, roll-out is performed. Following roll-out, the procedure is continued under VATS conditions, and an air-leak test, repair of lung parenchyma (control of air leakage), and confirmation of hemostasis are performed. A chest drain is inserted through the secondary port and positioned at the lung apex, and the operation is concluded.

Postoperative considerations and tasks

Postoperative management after neoDRATS follows an enhanced recovery after surgery protocol, with emphasis on early chest tube removal, early oral intake, adequate pain control, and early mobilization. Continuous suction is applied postoperatively, and the chest drain is removed approximately 4 hours after surgery if no air leakage is observed. If postoperative air leakage persists, chest tube management is continued according to standard institutional protocols. If air leakage persists for more than 2 days, chemical pleurodesis is considered in accordance with institutional practice. A chest radiograph is obtained on the following day, and discharge is permitted if no abnormalities are identified. Oral intake is initiated 2 hours after surgery, meals are resumed from dinner on the day of surgery, and oral analgesics are administered as needed. Early ambulation is actively encouraged to reduce postoperative complications.

Tips and pearls

Spatial awareness during console manipulation

In neoDRATS, precise three-dimensional spatial awareness of both bilateral working arms and the retraction arm is essential. Insufficient spatial recognition may result in arm interference, causing unintended instrument movement and potentially leading to serious complications. When any unusual resistance or discomfort is perceived during instrument manipulation at the console, the surgeon should avoid continuing forcefully, pause the procedure, and reconfirm arm positioning together with the bedside assistant.

Simultaneous bilateral arm movement and pointing laser adjustment to reduce interference

In DRATS, simultaneous movement of the right- and left-hand instruments can effectively reduce arm interference. This coordinated manipulation is particularly important within the main port in neoDRATS, where multiple robotic instruments are introduced through a single incision.

The pointing laser is generally aligned along the intercostal direction as a standard setting. However, when instrument interference occurs intraoperatively, practical adjustments include fine-tuning inter-arm clearance and slightly redirecting the pointing laser axis cranially. Such adjustments increase spatial clearance between the arms and help reduce interference. In particular, during right upper mediastinal lymph node dissection, cranial redirection of the pointing laser is an important technical tip for achieving smoother manipulation.

Positioning and role of the patient side assistant

Standing on the ventral side of the patient allows the bedside assistant to operate with a familiar perspective similar to that in mini-thoracotomy or ventral uniportal VATS. A curved suction device can be inserted through the secondary port, and thoracoscopic forceps or cotton swabs can be introduced through the main port as needed to assist with exposure. Close communication between the console surgeon and the bedside assistant enhances procedural safety. Experience in uniportal VATS is particularly valuable for understanding optimal visualization and exposure in reduced-port robotic surgery. In uniportal VATS, appropriate lung retraction and maintenance of the operative field are typically achieved by the bedside assistant. In neoDRATS, these concepts can be translated into console-controlled manipulation using the retraction arm. Therefore, familiarity with uniportal VATS techniques may facilitate safer and more effective implementation of this approach.

Technical considerations for robotic stapler use

Robotic staplers are generally introduced through the secondary port to optimize maneuverability. In right-sided procedures, the stapler is typically assigned to the left hand, whereas in left-sided procedures, it is assigned to the right hand. When necessary, reassignment between the left and right hands using the console hand-control settings can further improve flexibility. In addition, the recently introduced SureForm 30 curved-tip stapler offers improved intrathoracic maneuverability and can be used through the main port in selected cases.

Conversion from neoDRATS to conventional DRATS

In some patients, particularly those with a small physique or during upper mediastinal lymph node dissection, interference of the retraction arm may occur despite careful arm configuration. In such situations, the retraction arm can be temporarily canceled, and the procedure can be continued using a conventional DRATS configuration. This flexible conversion effectively resolves arm interference without compromising operative safety.

Flexible use of the retraction arm

Because the retraction arm in neoDRATS is introduced through the secondary port, lung retraction toward the dorsal, ventral, and caudal directions is generally straightforward, whereas cranial retraction may be limited. In such situations, switching one of the main-port arms to serve as the retraction arm enables appropriate exposure of the operative field.

Visualization without CO2 insufflation and emergency management

As CO₂ insufflation is not routinely used, visualization may be compromised in patients with diaphragmatic elevation or cardiomegaly. In such cases, cotton-assisted retraction by the bedside assistant is effective. When emergency roll-out is required due to massive intraoperative bleeding, compression of the bleeding point using the arm inserted through the secondary port, combined with curved suction, is recommended. The dorsal camera arm in the main port should be maintained while the other arms are elevated, and, if necessary, the ventral incision can be extended to allow rapid access to the pulmonary hilum.

Discussion

In this article, we described in detail the surgical technique of neoDRATS, which represents an advanced form of DRATS practiced at our institution. Unlike RPRATS approaches that primarily aim to minimize the number of ports, neoDRATS is fundamentally designed to achieve stable lung retraction and robotic stapling under the direct control of the console surgeon, which constitutes its essential conceptual feature.

In recent years, RPRATS, including uniportal RATS, has been reported as an effort to further minimize surgical invasiveness. However, with currently available robotic systems, limitations in working space and instrument interference related to instrument diameter and stapler size may compromise maneuverability, particularly in patients with smaller physiques, such as many Asian patients. By adopting a dual-portal approach to secure adequate working space while fully utilizing all four arms of the da Vinci Xi system, neoDRATS represents a practical solution that balances reduced-port access with operative safety and maneuverability.

Another distinctive characteristic of neoDRATS is its fifth intercostal space–based approach, which allows surgeons to reproduce operative views and procedural workflows familiar from conventional VATS and thoracotomy. This continuity with established techniques may contribute to a smoother learning curve and facilitates prompt conversion to VATS or thoracotomy when unexpected intraoperative situations arise. The ability to integrate robotic innovation while preserving familiarity with conventional thoracic surgical anatomy and workflow is a key advantage of this approach.

Several limitations of this study should be acknowledged. First, this report is based on the experience of a single institution and a limited number of surgeons, and it does not systematically evaluate perioperative outcomes or long-term oncologic results. Therefore, further validation through multicenter studies and assessment of reproducibility by other surgeons are warranted. Second, because neoDRATS relies on the full use of all robotic arms and console-surgeon-driven lung retraction and stapling, adequate proficiency with the da Vinci Xi system is required, and a learning curve may exist during the initial adoption phase. Third, the present description primarily focuses on lobectomy, and the applicability of this technique to segmentectomy or more complex procedures requires further investigation. In addition, because CO₂ insufflation is not routinely used, visualization may be limited in certain patients, emphasizing the importance of appropriate patient selection and effective team coordination. Finally, this technique was developed using the da Vinci Xi platform at our institution. While the fundamental concept may be adaptable to other robotic systems, including the da Vinci X, its feasibility has not been formally evaluated. In addition, the applicability of this technique to newer-generation systems, such as the da Vinci 5, remains to be determined.

Despite these limitations, neoDRATS offers a practical and well-balanced solution within the spectrum of RPRATS by combining console-surgeon-driven operability, procedural safety, and compatibility with conventional thoracic surgical approaches. With continued advancements in robotic platforms and related devices, the indications for this technique may further expand and be applied to a broader range of clinical scenarios. We hope that this report will contribute to a better understanding of neoDRATS and support the safe and thoughtful adoption of RPRATS.

Conclusions

We have outlined a step-by-step surgical technique for DRATS performed at our institution. neoDRATS is unique among DRATS approaches in that it uses all four arms of the da Vinci Xi system, enabling console-surgeon-driven lung retraction and stapling. In addition, because the approach is primarily based on the 5th intercostal space, it facilitates reproduction of the familiar views and procedural workflow of conventional VATS and thoracotomy for thoracic surgeons, and also allows a smooth transition or conversion when necessary. With further development of next-generation robotic platforms and ongoing innovation in related devices, RPRATS is expected to become more widely adopted.

Acknowledgments

The authors would like to thank the operating room staff and bedside assistants at Tokyo Metropolitan Bokutoh Hospital for their continuous support and collaboration in the development and refinement of the neoDRATS technique. We also express our sincere gratitude to Drs. Hideki Ujiie and Masato Chiba (Division of Thoracic Surgery, Department of Surgery, Kindai University, Osaka, Japan), as well as Drs. Jun Suzuki and Hikaru Watanabe (Department of Surgery II, Faculty of Medicine, Yamagata University, Yamagata, Japan), for their valuable discussions, technical insights, and contributions to the conceptual development of dual-portal robotic-assisted thoracic surgery.

Footnote

Provenance and Peer Review: This article was commissioned by the Guest Editor (Hideki Ujiie) for the series “Reduced Port Robotic-assisted Thoracic Surgery” published in Journal of Visualized Surgery. The article has undergone external peer review.

Reporting Checklist: The authors have completed the SUPER reporting checklist. Available at https://jovs.amegroups.com/article/view/10.21037/jovs-2025-1-61/rc

Peer Review File: Available at https://jovs.amegroups.com/article/view/10.21037/jovs-2025-1-61/prf

Funding: None.

Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://jovs.amegroups.com/article/view/10.21037/jovs-2025-1-61/coif). The series “Reduced Port Robotic-assisted Thoracic Surgery” was commissioned by the editorial office without any funding or sponsorship. H.E. reports receiving lecture fees and honoraria from Medtronic and Johnson & Johnson. The authors have no other 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. This study was approved by the institutional review board of Tokyo Metropolitan Bokutoh Hospital (No. 05-030) and was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient for the publication of this study, accompanying images, and the videos. A copy of the written consent is available for review by the editorial office of this journal.

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/.

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