Pulmonary artery anastomosis during lung transplantation: a novel technique

Introduction

Pulmonary artery anastomosis (PAA) is a critical step in lung transplantation. However, the techniques used in this procedure can vary among medical centers (1-4). Conventional suture techniques include interrupted, simple continuous, and stapler-assisted sutures, each of which has advantages and disadvantages (5-7). Although PAA is relatively straightforward, conventional suture techniques can lead to severe intraoperative complications, such as profuse bleeding, stenosis, distortion of the reconstructed vessels, and postoperative anastomotic mural thrombus. To enhance surgical field exposure and reduce bleeding and anastomotic torsion, we have introduced the use of Prolene sutures and a polyester cardiovascular patch and assistance to facilitate pulmonary stump traction. However, these experiences are limited to isolated case reports; detailed records on PAA techniques during lung transplantation are limited.

Here, we present a modified PAA technique to address these potential complications without increasing the anastomosis time. We present this article in accordance with the SUPER reporting checklist (available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1147/rc).

Preoperative preparations and requirements

Indications for lung transplantation include a wide range of pulmonary diseases affecting the airways, parenchyma, and vasculature. All seven patients in our study had end-stage lung disease.

The anesthesia protocol and the incision for lung transplantation adhere to standard lung transplantation protocols. The primary innovation is the enhanced pulmonary anastomosis technique. This novel approach requires the donor and recipient to have an adequate length of pulmonary artery.

Step-by-step description

Prior to commencing PAA during lung transplantation, it is essential to realign the donor and recipient stumps to their natural anatomical alignment. This process involves the eversion of the donor-recipient stump, ensuring precise alignment of the intima of the donor and recipient arteries. Both ends of the anastomosis are secured using 5-0 Prolene sutures (Ethicon, Somerville, NJ, USA) to ensure stability and traction. Subsequently, these sutures are straightened at both ends of the anastomosis to facilitate the suturing of the posterior wall of the arterial anastomosis. Furthermore, an additional 5-0 Prolene suture is typically introduced to the posterior wall to optimize the alignment of the donor and recipient pulmonary arteries while ensuring a clear field of vision. This suture is knotted at one end of the anastomosis and used to execute a sleeve-like simple continuous suture; this involves suturing to the hanging thread, followed by sequential trimming of the hanging thread (Figures 1-4). After a lap of continuous suturing and exhaustion, the arterial anastomosis is finalized through knotting. This technique is demonstrated in Video 1.

Figure 1 Everted and suspended at both ends and midpoint.

Figure 2 Suture the posterior wall.

Figure 3 Suture the anterior wall.

Figure 4 PAA in the partially open state. PAA, pulmonary artery anastomosis.

Postoperative considerations and tasks

No differences were observed between the novel and conventional PAA techniques in the postoperative management of patients. After the completion of pulmonary vein anastomosis, the last suture was left untied (a needle cannot be tied). The pulmonary artery was fully exhausted before the pulmonary vein was tied. After opening, the artery was observed for torsion, angulation, oozing, and color changes to the lung surface after reperfusion. Postoperative computed tomography was performed as needed.

Tips and pearls

Evert the donor-recipient stump before performing pulmonary anastomosis to ensure precise alignment between the intima of the donor and recipient arteries.

Discussion

PAA is a crucial step in lung transplantation; the quality of the anastomosis has a significant impact on the circulation and function of the transplanted lung (1-3). Conventional PAA techniques, such as interrupted, simple continuous, and stapler-assisted sutures, can be associated with varying degrees of bleeding, torsion, deformity, and other complications (4-7).

We have introduced a novel PAA technique without increasing the anastomosis time. This technique involves end-folding the stumps of the donor and recipient pulmonary arteries, which is equivalent to using a polyester cardiovascular patch before anastomosis. A unique traction line suspension system allows the anastomosis to be performed by a single surgeon.

In 2022, we used this novel technique to perform lung transplantation in seven patients. All patients were male, aged 53–74 years (median age, 66 years), with a median body mass index of 19.66 kg/m². Four and three of them underwent left and right lung transplantation, respectively.

The mean duration of arterial anastomosis was 14.14±3.48 minutes. Notably, no instances of blood leakage, angulation, or torsion were observed at the arterial anastomosis site after opening the pulmonary artery. Postoperative computed tomography of the chest revealed no stenosis or thrombosis at the anastomosis site (Figures 5,6). Our method has several advantages over conventional techniques. First, the end-folded pulmonary artery acts like a gasket, preventing distortion and angulation caused by poor alignment, avoiding leakage, and reducing the risk for postoperative mural thrombosis of the anastomosis by ensuring proper alignment of the vascular intima. Second, the suspension wire system allows for effective anastomosis of mismatched pulmonary arteries by aligning the pulmonary artery and reducing the needle distance on the side with the smaller diameter. It also has a few limitations. First, sufficient length of the pulmonary artery must be preserved in the donor and recipient. Second, care must be taken to avoid over-rotating the pulmonary artery during the turning process to prevent excessive tension in the anastomosis.

Figure 5 Computed tomography after left lung transplantation.

Figure 6 Computed tomography after right lung transplantation.

Conclusions

Our novel cuff anastomosis method reduces the risk of thrombosis, torsion, and stenosis in reconstructed arteries without increasing anastomosis duration. This method is a critical step in improving the process of lung transplantation.

Acknowledgments

Funding: None.

Footnote

Reporting Checklist: The authors have completed the SUPER reporting checklist. Available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1147/rc

Peer Review File: Available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1147/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1147/coif). J.H. serves as Executive Editor-in-Chief of Journal of Thoracic Disease. 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. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for publication of this article and accompanying images. 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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