Robot-assisted single lung transplantation.

To the Editor: Currently, lung transplantations are typically performed via a transverse thoracosternotomy or a sternotomy for double lung transplantation, or a posteriolateral thoracosternotomy for single lung transplantation. However, these extremely invasive approaches may contribute to early post-operative pain, delay wound healing, and cause chronic post-thoracotomy neuralgia, which can affect patient's quality of life.[1,2] Of interest, several minimally invasive surgical methods for lung transplantation were reported.[3,4] Furthermore, robotic surgical systems are now widely used in the field of thoracic surgery. Herein, we reported a case of performing robot-assisted right single lung transplantation for a patient with end-stage chronic obstructive pulmonary disease (COPD). A 59-year-old male recipient (weight, 52 kg; height, 170 cm) with end-stage COPD underwent bilateral pulmonary bullae resection via open approaches ten years ago [Figure 1A]. The pre-operative lung function of the recipient showed a forced expiratory volume in 1 s of 0.27 L, a forced vital capacity of 0.52 L, and a vital capacity of 1.20 L. Blood gas test showed a pH of 7.35, a partial pressure of oxygen of 88.1 mmHg, a partial pressure of carbon dioxide of 50.8 mmHg, a concentration of HCO3− of 26.1 mmol/L, and an oxygen saturation of 97.6% (fraction of inspired oxygen of 41%). Transthoracic echocardiogram showed an ejection fraction of 60% and a pulmonary artery systolic pressure of 30 mmHg. After waiting for 69 days, a matched donated lung was found from a 40-year-old male who developed cerebral hemorrhage, with a weight of 65 kg, a height of 170 cm, and an oxygen index of 450 mmHg. With full consent and an allocation process, the graft lung was procured and transported to our hospital.Figure 1: (A) Pre-operative chest computed tomography of the recipient. (B) The pulmonary artery was cut by robotic scissors. (C) The right main bronchus was cut by robotic scissors. (D) End-to-end half-continuous anastomosis for the bronchus. (E) Anastomosis for the pulmonary artery. (F) Anastomosis for the left atrium. (G) The skin incision was closed with an intradermal suture. (H) Post-operative chest computed tomography of the recipient.The recipient was placed in the lateral decubitus position and administered general anesthesia with a left-sided double-lumen endotracheal intubation. A robot system (Si da Vinci Robotic System, Intuitive Surgical, Inc., Mountain View, CA, USA) was positioned into the operating field over the patient's head. An 8.0-cm utility incision was made in the sixth intercostal space, and a silicon rubber wound protector was used. Four port incisions (1.0 cm each) were then made. The first port, which was located on the midaxillary line in the seventh intercostal space, was used for the robotic camera. The second port, which was located on the midclavicular line in the fifth intercostal space, was used for the right robotic arm with the robotic hook cautery, scissors, and needle holder being positioned. The third port was made on the scapular line in the ninth intercostal space for the left arm and robotic long forceps. The fourth port was made on the midaxillary line in the fourth intercostal space for the vascular block clamps. Extensive pleural adhesions were encountered in the right thoracic cavity. These were carefully managed, and blood infiltrations from the chest wall were carefully treated one by one. Next, the pulmonary veins were prepared and freed from the pericardium. The right upper and lower pulmonary veins were cut sequentially using a stapler (Ethicon, Johnson & Johnson, New Brunswick, NJ, USA). The right pulmonary artery was then prepared and clamped using a vascular block clamp through the fourth port. The anterior apical branch of the right pulmonary artery was cut using the stapler. The right pulmonary artery was divided by the hot scissors distal to the anterior apical branch [Figure 1B]. Finally, the right main bronchus was divided at the level of the two cartilage rings from the carina [Figure 1C]. The right lung was excised and removed through the 8-cm wide assistant incision. Following pneumonectomy, careful hemostasis was performed. The donor lung was prepared with a cold ischemic time of 300 min. The donor lung was gently placed into the chest cavity by hand via the 8-cm assistant incision on the right chest wall without rib spreading. The graft was implanted using the novel robot-assisted technique beginning with the bronchial anastomosis followed by the anastomosis of pulmonary artery and the atrial cuff. Bronchial reconstruction with the end-to-end anastomosis was performed robotically with the surgeon sitting at the control console. A half-continuous suture method was applied using two 3/0 prolene sutures (Ethicon, Johnson & Johnson) according to a previously reported anastomosis method.[5] After completing the anastomosis, the two running sutures were tightened with robotic instruments and the two anastomotic orifices were closed. The two knots were separately tied to the end of the continuous sutures. The surrounding tissues were also sutured (3-0 polydioxanone sutures) to cover the bronchial anastomosis [Figure 1D]. The bronchial anastomosis time was 12 min. The recipient's right interlobar pulmonary artery was then anastomosed to the donor's main pulmonary artery with half-continuous 5/0 prolene, taking into account the bronchus length, to ensure no undue tension or excessive length [Figure 1E]. The time of the arterial anastomosis was 28 min. Finally, the recipient's left atrium was anastomosed to the donor's atrial cuff using half-continuous 4/0 prolene [Figure 1F]. The atrial anastomosis time was 32 min. After reperfusion and ventilation, two chest tubes were placed for drainage. A skin incision was closed with an intradermal suture [Figure 1G]. The bronchial anastomosis was examined using portable bronchoscopy. Then, the patient was transferred to the intensive care unit for recovery and was extubated after 36 h. Post-operative treatment with tacrolimus and corticoids was prescribed. On post-operative day 9, chest computed tomography showed compatible post-transplantation lung expansion [Figure 1H]. The patient was discharged on post-operative day 19. The lung functional assessments showed a forced expiratory volume in 1 s of 1.01 L, a forced vital capacity of 1.13 L, and a vital capacity of 1.71 L. The patient achieved 350 m for his 6-min walk test. The bronchial anastomoses appeared satisfactory. Lung transplantation is currently the only accepted treatment for end-stage pulmonary failure. The conventional open approach for lung transplantation is associated with numerous clinically relevant problems and complications during the early and late post-operative periods. The da Vinci surgical system provides superior optics with a three-dimensional endoscope and allows for enhanced dexterity with the EndoWrist instrument system. Such robotic instruments can provide several benefits in very complex procedures such as the bronchial anastomosis for sleeve lobectomy. The present case had a history of bilateral pulmonary bullae resection with extensive pleural adhesions. We made full use of the advantages of the da Vinci robot, such as the three-dimensional high-definition vision and flexible rotating wrist equipment, which allowed us to perform difficult dissections, reliable hemostasis, and precise anastomosis. Using robot-assisted lung transplantation, the anastomoses (including of the bronchus, pulmonary artery, and left atrium) were the most important and distinctive procedures compared with traditional lung transplantation. In our patient, all procedures, including suturing and knot tying, were performed by robotic instruments. A limitation of the robotic surgery is the lack of haptic feedback of the robotic instruments, and the precise management relies on visual perception to avoid suture fracture during anastomosis and knot tying. Additionally, to deal with unexpected intra-operative conditions, the assistant at the operating table requires a high level of training and should be able to independently perform minimally invasive lung surgery. Robot-assisted single lung transplantation was safe and feasible for an experienced robotic team and carefully selected recipients. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal his identity, but anonymity cannot be guaranteed. Acknowledgements Author thanks Jingyu Chen, Jinzhen Cai, Jinyan Xing, Lipeng Zhao, Junhua Fu, Xiuzhi Yang, Wenchao Bian, Mingying Dai, Gang Wang, Xiumei Chu, Wenxing Du, and Zhe Wu for contributions to this study, and Liwen Bianji (Edanz) (www.liwenbianji.cn) for editing the English text of a draft of this manuscript. Conflicts of interest None.