Safety tips for pulmonary artery management using clipping combined with an energy device: a surgical technique in robotic-assisted thoracic surgery

Introduction

Pulmonary artery (PA) management is a critical step in lung resection and requires meticulous technique to prevent catastrophic bleeding (1,2). In robotic-assisted thoracic surgery (RATS), enhanced visualization and instrument articulation allow precise dissection in confined spaces (1). However, the absence of tactile feedback and the use of long instruments may increase the risk of unintentional vessel traction or injury, particularly during instrument withdrawal (3).

In current clinical practice, PA branches are most commonly managed using vascular staplers or ligation techniques, with energy-based vessel sealing devices also widely adopted. While these approaches are generally reliable, they may be technically challenging in the robotic setting, particularly for small-caliber branches located in confined spaces or with unfavorable angulation. In addition, concerns remain regarding sealing reliability, thermal injury, and delayed hemorrhage, especially in fragile pulmonary arteries (4,5).

Clipping represents an alternative method for PA control; however, its use in thoracic surgery remains less standardized. Furthermore, improper clip placement or inadvertent contact during instrument withdrawal can lead to unexpected complications, including rare cases of clip detachment (6).

However, in thoracic surgery, the use of clipping for PA branches is less standardized, and detailed technical guidance regarding its safe and effective application remains limited.

To address these issues, we adopted a technique combining proximal clipping and distal division using an energy-based vessel sealer, referred to as the clipping plus vessel sealing (CV) technique. While the conceptual combination of clipping and energy-based division is not entirely new, the present approach emphasizes a structured and standardized workflow, along with clearly defined technical principles and safety considerations tailored to the robotic setting.

This report describes the technical details of the CV technique and evaluates its clinical feasibility in RATS, with a focus on practical tips to prevent procedure-related complications. We present this article in accordance with the SUPER reporting checklist (available at https://jovs.amegroups.com/article/view/10.21037/jovs-2026-1-0003/rc).

Preoperative preparations and requirements

The study was approved by the Ethics Committee of NTT Medical Center Sapporo (No. 576-01), and was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patients for the publication of this study, accompanying images and the video. A copy of the written consent is available for review by the editorial office of this journal.

All patients underwent standard preoperative evaluation for robotic lung resection, including contrast-enhanced computed tomography to assess tumor characteristics and vascular anatomy. Three-dimensional reconstruction was utilized when necessary to better understand the branching patterns of the PA.

The CV technique was considered in cases where small-caliber PA branches (≤5 mm) were anticipated, particularly in anatomically complex regions such as the upper lobes. Careful preoperative planning was performed to evaluate the feasibility of clip placement and safe application of the vessel sealing device.

No additional instruments beyond standard robotic surgical equipment were required. A medium-large polymer clip (Hem-o-lok^®) and an energy-based vessel sealing device (Vessel Sealer Extend^®) were prepared for all cases.

The surgical team was required to be familiar with RATS and standard pulmonary artery management techniques, as well as the specific precautions associated with clip application and energy-based vessel sealing.

Special equipment and devices

All procedures were performed using the da Vinci Xi surgical system (Intuitive Surgical, Sunnyvale, CA, USA). A medium-large polymer clip (Hem-o-lok^®, Teleflex, Wayne, PA, USA) was used for proximal vascular control, and an energy-based vessel sealing device (Vessel Sealer Extend^®, Intuitive Surgical) was used for distal division. These instruments were used in standard configuration without modification.

Surgical team and training

All procedures were performed by an experienced thoracic surgeon with substantial experience in RATS. The surgical team consisted of a console surgeon, a bedside assistant, an anesthesiologist, and operating room nurses. The assistant was responsible for instrument exchange, suction, and clip application support as needed.

No additional specialized training beyond standard robotic surgical training was required for the CV technique. However, familiarity with PA handling and basic robotic surgical skills was considered essential for safe implementation.

Step-by-step description

Patients were placed in the lateral decubitus position. Port placement was based on a modified Cerfolio approach (1). Four robotic ports were typically placed in the 8th or 9th intercostal spaces, with the most anterior port occasionally positioned in the 7th intercostal space depending on anatomical conditions. An assistant port was created in the 4th or 5th intercostal space anteriorly, differing from the original Cerfolio method in which the assistant port is placed in a more caudal intercostal space.

Patient selection and indications

This retrospective technical report reviewed consecutive patients who underwent RATS between April 2018 and April 2023. Among 184 robotic lung resections, the CV technique was selectively applied to small-caliber PA branches deemed unsuitable for stapling but requiring secure proximal control.

In our practice, the CV technique was primarily applied to PA branches with an estimated diameter of ≤5 mm. This threshold was determined based on both technical feasibility and the physical characteristics of the clip system. Although the medium-large polymer clip can accommodate a vessel width of up to approximately 9 mm, the vessel becomes flattened after clipping, effectively increasing its transverse dimension. Therefore, to ensure secure clipping with an adequate safety margin, vessels with a pre-clipping diameter of ≤5 mm were considered most suitable.

The indication was determined intraoperatively, particularly in situations where stapler application was technically difficult due to limited working space, unfavorable angulation, or anatomical constraints. In addition, in small-caliber vessels, stapler application may be less suitable due to both anatomical and mechanical factors. From a technical perspective, limited working space and unfavorable angulation may hinder proper positioning of the stapler jaws. From a mechanical standpoint, the relationship between staple size and vessel diameter may result in a relatively limited number of staples engaging the vessel wall, potentially affecting the uniformity of compression and sealing. By contrast, polymer clips provide circumferential compression across the vessel segment, which may offer a more uniform occlusion in selected small-caliber branches. Conversely, vessels with a larger diameter, significant calcification, or marked fragility were considered less suitable and were managed using alternative methods such as stapling.

In this study, the CV technique was applied to a total of 41 small PA branches in 28 patients. The surgical procedures included 20 lobectomies and 8 segmentectomies. The median number of treated PA branches per patient was 1 (range, 1–3). The median operative time was 148 minutes (interquartile range, 127–194 minutes; range, 83–246 minutes).

The technique was most frequently applied in upper lobe resections, particularly in the left upper lobe, reflecting the anatomical complexity and limited accessibility of segmental PA branches in these regions.

No intraoperative bleeding or CV technique-related complications were observed. In addition, no postoperative hemorrhagic events or complications suggestive of vascular injury were identified during the follow-up period.

Vessel exposure and preparation

After standard hilar dissection, the target PA branch was circumferentially exposed and fully skeletonized. Adequate dissection was essential to ensure that both the clip and energy device could be applied directly to the vessel without incorporating surrounding tissue.

For surgical reproducibility, at least approximately 10 mm of circumferentially skeletonized vessel length was considered necessary. This length allows placement of the proximal clip, maintenance of a safety gap between the clip and the transection line, and secure application of the vessel sealing device jaws. When feasible, approximately 15 mm of exposed vessel length was preferred to provide a greater margin for safe manipulation.

Proximal clipping

Proximal control was achieved using a single medium-large polymer clip (Hem-o-lok^®). The clip was applied at an adequate distance from the vessel origin, approximately equivalent to the width of one clip, to secure a uniform segment of the artery while preserving sufficient working space distally (Figure 1).

Figure 1 Practical application of the clipping plus vessel sealing technique. Intraoperative robotic images demonstrating the practical application of the CV technique. A single polymer clip (medium-large size) is applied to the PA branch at a distance of approximately one clip’s width from the vessel origin. This spacing prevents mechanical interference with the vessel root and facilitates safe application of the distal vessel sealing device. The corresponding operative procedure is shown in Video 1. The dimensions of the instruments are shown to illustrate the spatial requirements for clip placement and vessel sealing, and to support safe and reproducible application of the technique. CV, clipping plus vessel sealing; PA, pulmonary artery.

Distal vessel sealing and division

After confirming stable clip placement, distal division of the PA branch was performed using an energy-based vessel sealing device (Vessel Sealer Extend^®).

The sealing and transection were conducted several millimeters distal to the clip to prevent thermal or mechanical interference with the clip. Importantly, division too close to the clip was avoided. A minimum distance equivalent to approximately one clip’s width was maintained between the clip and the transection line to reduce the risk of clip displacement or detachment after vessel division.

Instrument withdrawal

A critical technical point was careful handling during removal of the clip applier. Prior to withdrawal, sufficient separation between the instrument and the sealed vessel was confirmed. The clip applier was then gently withdrawn along the axis of insertion under direct visualization to avoid inadvertent contact or traction on the vessel (Figure 2). The key steps of the CV technique, including clip placement, distal sealing, and safe removal of the clip applier, are demonstrated in Video 1.

Figure 2 Key precaution during clip applier removal in the CV technique. Annotated intraoperative images emphasizing a critical precaution during removal of the clip applier. Before withdrawal, the instrument should be fully disengaged from the vessel and positioned away from the applied clip. Slow and straight withdrawal along the axis of insertion helps prevent accidental contact with the clip or inadvertent vessel traction, which could result in vascular injury. CV, clipping plus vessel sealing.

Postoperative considerations and tasks

Patients were monitored according to standard postoperative protocols following robotic lung resection. Particular attention was paid to signs of vascular complications related to PA management. Postoperative monitoring included chest tube output (volume and character), serial hemoglobin measurements, and clinical assessment for hemodynamic instability.

The median follow-up duration was 47.1 months (range, 1.6–62.0 months), and the median chest tube duration was 2 days (range, 1–9 days). During this period, no delayed hemorrhage, pseudoaneurysm formation, or other complications related to the CV technique were observed.

Tips and pearls

• Ensure complete circumferential skeletonization of the target PA branch before clip application.
• Apply the clip approximately one clip’s width away from the vessel origin to secure a uniform arterial segment and preserve distal working space.
• Confirm firm locking and perpendicular orientation of the polymer clip.
• Activate the vessel sealer sufficiently distal to the clip to avoid thermal or mechanical effects on the clip.
• Withdraw the clip applier slowly and straight under direct vision to prevent inadvertent traction on the clipped vessel.
• Maintain an adequate distance between the clip and the transection line (at least one clip’s width) to reduce the risk of clip detachment after vessel division.

Discussion

Safe PA management is essential in RATS, where uncontrolled bleeding can necessitate emergency conversion (1,2). Although energy devices have demonstrated reliable sealing of small pulmonary vessels, histologic studies suggest that energy sealing alone provides lower burst pressures than suture ligation (4,5). The CV technique adds a proximal mechanical safeguard by combining clipping with distal energy sealing.

In current practice, PA branches are most commonly managed using stapling or ligation, while clipping is less standardized in thoracic surgery. In this context, the CV technique provides a structured approach that integrates clipping with energy-based division under defined technical principles.

In our experience, the CV technique was applied to 41 PA branches without intraoperative bleeding, device-related complications, or the need for additional hemostatic measures. This hybrid approach leverages the security of mechanical occlusion and the precision of energy-based division in confined robotic spaces.

Potential complications associated with polymer clips or energy devices were not observed in our series. The CV technique inherently mitigates these risks by limiting the role of the energy device to thin distal vessel segments and emphasizing careful clip handling. In particular, maintaining an adequate distance between the clip and both the vessel origin and the transection line (approximately one clip’s width) is considered essential to minimize mechanical stress and reduce the risk of clip displacement or detachment after division (6).

From a practical perspective, the CV technique may be particularly beneficial during the early phase of RATS adoption. The absence of tactile feedback and the use of long robotic instruments can increase the risk of inadvertent vessel traction, especially during instrument withdrawal (3). By providing secure proximal mechanical control before energy-based division, the CV technique offers a practical and structured strategy to mitigate this risk. Importantly, this approach requires no additional devices beyond standard robotic instruments and can be readily integrated into routine workflows. Its simplicity may also make it well suited for reduced-port or uniportal robotic approaches, where working space is limited and precise instrument handling is critical.

While the conceptual combination of clipping and energy-based division is not entirely new, the present report provides a standardized description of this approach, including clearly defined indications, procedural steps, and safety considerations. These features may enhance the reproducibility and clinical applicability of the technique.

Limitations

This study has several limitations. First, it is a retrospective analysis from a single institution with a relatively small sample size, which may limit the generalizability of the findings. Second, no comparative analysis with other PA management techniques, such as stapling or clipping alone, was performed. Therefore, the relative advantages of the CV technique cannot be definitively established.

In addition, the applicability of this technique may be limited in certain anatomical or pathological conditions. Specifically, larger-caliber vessels, heavily calcified arteries, or fragile vessels with inflammatory changes may not be suitable for this approach. Furthermore, adequate vessel length and mobility are required to ensure safe clip application and energy sealing.

Future studies involving larger cohorts and comparative designs are warranted to further validate the safety and utility of this technique.

Conclusions

The CV technique represents a simple and practical method for PA management in RATS. In our experience, this approach was associated with favorable perioperative outcomes without procedure-related complications; however, further validation in larger and comparative studies is warranted.

Acknowledgments

The authors thank the operating room staff and surgical team members at NTT Medical Center Sapporo for their support during the procedures. During the preparation of this work, the author(s) used ChatGPT (OpenAI) for assistance with language refinement and structural editing. After using this tool, the author(s) reviewed and edited the content as needed and take full responsibility for the content of the publication.

Footnote

Reporting Checklist: The authors have completed the SUPER reporting checklist. Available at https://jovs.amegroups.com/article/view/10.21037/jovs-2026-1-0003/rc

Peer Review File: Available at https://jovs.amegroups.com/article/view/10.21037/jovs-2026-1-0003/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jovs.amegroups.com/article/view/10.21037/jovs-2026-1-0003/coif). H.D. reports receiving lecture fees from medical device companies (e.g., Intuitive Surgical, Johnson & Johnson, and Medtronic) 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. The study was approved by the Ethics Committee of NTT Medical Center Sapporo (No. 576-01), and was conducted in accordancewith the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patients for the publication of this study, accompanying images and the video. 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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