Robotic-assisted Left Pneumonectomy For Vanishing Lung Syndrome

Summary

Robotic-assisted pneumonectomy is safe and effective in the management of Vanishing Lung Syndrome, with reduced morbidity and faster recovery times.

Abstract

Vanishing Lung Syndrome (VLS) is a rare, severe form of bullous pulmonary disease characterized by giant bullae occupying more than 30% of the hemithorax, which can easily be misdiagnosed as a pneumothorax. While cigarette smoking is the primary cause, other factors such as Ehlers-Danlos Syndrome and alpha-1 antitrypsin deficiency have also been associated with the condition. Surgical management, including pneumonectomy, remains the gold standard for severe VLS cases. This case report aims to highlight the effectiveness of the robotic approach and the benefits of robotic-assisted left pneumonectomy to treat VLS. Given that conservative management failed to improve this patient's symptoms, a robotic-assisted pneumonectomy was performed, offering precise dissection and faster recovery compared to traditional open thoracotomy or video-assisted thoracoscopic surgery (VATS). Four robotic ports, along with an assistant port, were utilized to gain access to the left chest. Dissection proceeded by dividing the inferior pulmonary ligament and then the pulmonary hilum, followed by the division of the inferior pulmonary vein and the left main bronchus in a sequential order to complete the pneumonectomy safely. The air leak test was negative, and the specimen was removed via the assistant port. Postoperative recovery was uneventful, and the patient was discharged on postoperative day 3. This robotic-assisted surgery offers smaller incisions via a five-incision approach, enhanced visualization, and reduced morbidity, making it a promising option for the management of VLS. This protocol is purposed to demonstrate a robotic-assisted pneumonectomy technique for VLS and its benefits. Nevertheless, further studies are needed to assess long-term outcomes and confirm the role of minimally invasive techniques in treating this rare condition.

Introduction

Vanishing Lung Syndrome (VLS) is a rare and poorly understood severe form of bullous pulmonary disease characterized by giant bullae occupying more than 30% of the hemithorax^1,2. Cigarette smoking is reportedly the major cause of these giant bullae, although other factors like Ehlers-Danlos Syndrome and alpha 1-antitrypsin deficiency have been associated with the pathology¹. The characteristic giant bullae seen in VLS can be easily misdiagnosed as pneumothorax. While chest x-rays can be helpful in proper diagnosis, high-resolution computed tomography (HRCT) has been recommended to properly visualize the thin septations and pattern of lung collapse often seen in VLS^3,4.

Surgical management remains the gold standard for significant bullous disease, with the current literature describing both open thoracotomy and video-assisted thoracoscopic surgery (VATS)^1,2,5. Despite the higher morbidity and mortality rates of pneumonectomy for benign disease compared to malignant indications, the outcomes for patients with benign disease can be especially favorable with refined operative techniques and meticulous patient selection^6,7,8. The threshold for pneumonectomy in patients with vanishing lung syndrome has traditionally been a preoperative Forced Expiratory Volume in one second (FEV1) greater than 2 L. But this this should not be considered an absolute exclusion criterion as recent evidence demonstrates that pneumonectomy can be safely performed in patients with FEV1 ≤ 2 L. Functional operability is best assessed using predicted postoperative (ppo) values: most guidelines recommend a ppo FEV1 and Diffusing Capacity of the Lungs for Carbon Monoxide (DLCO) ≥ 40% of predicted as the minimum threshold for safe pneumonectomy^3,9. Robotic-assisted surgery has been shown to be non-inferior to VATS, emerging as a promising minimally invasive technique for lung resection, offering advantages such as reduced morbidity, shorter recovery times, precise tissue dissection, and a lower rate of conversion to open thoracotomy¹⁰.

Case Presentation

A 41-year-old previously healthy African American male, a current smoker, presented with progressive dyspnea on exertion requiring oxygen. The patient denied any significant past medical history or family history of pulmonary diseases, other than his smoking history.

A chest X-ray revealed a markedly diminished left lung volume with a hyperinflated right lung (Figure 1). The mediastinum exhibited a right-ward shift. Further evaluation with a computed tomography (CT) scan of the chest demonstrated near-complete collapse of the left lung with the cardiac borders in the right hemithorax. Although VLS often involves a single lobe, this case demonstrated complete involvement of the entire left lung. There were no signs of obvious masses, consolidations, or bronchiectasis. Right heart catheterization demonstrated mildly elevated right heart pressures. Pulmonary function tests (PFTs) revealed a restrictive pattern, characterized by reduced total lung capacity and forced vital capacity. The FEV1 was 31% of predicted values, while the DLCO was 35% of predicted values. Quantitative perfusion scan also demonstrated a 2.5% perfusion of the left lung, further supporting the diagnosis of VLS.

Given the severity of the patient's symptoms and the failure of conservative management (supplemental oxygen therapy and pulmonary rehabilitation), surgical intervention was considered. A decision was made to proceed with a robotic-assisted left pneumonectomy.

Protocol

Written informed consent to use and publish data was obtained, along with procedure consent.

1. Preoperative preparation

1. Position the patient in the right lateral decubitus position with the left arm raised to 90° anteriorly and supported by appropriate cushioning.

2. Surgical approach

1. Place four robotic ports along the eighth intercostal space to gain access to the left chest: one at the anterior axillary line, one at the mid-axillary line, one at the posterior axillary line, and about 5 cm posterior to the posterior axillary line.
2. Place an assistant port just above the diaphragm in the ninth intercostal space at the mid-axillary line.
3. Dock the robot in the standard fashion, maintaining the sterile field, then insert the camera through the port at the mid-axillary line of the eighth intercostal space.
4. Once the camera is inserted, insert the other instruments as follows:
   1. Insert the curved bipolar dissector in the port at the anterior axillary line of the eighth intercostal space.
   2. Insert the straight grasper in the port at the posterior axillary line of the eighth intercostal space.
   3. Finally, insert the tips-up grasper at the remaining port site.
5. With all the instruments in place, proceed with adhesiolysis as needed to gain proper mobilization of the lung from the chest wall.
6. Begin the dissection by dividing the inferior pulmonary ligament, as it leads to the inferior pulmonary vein. Utilize the curved bipolar dissector to perform the dissection and apply electrocautery as needed.
   1. Continue the dissection to free up the inferior pulmonary vein.
   2. Continue the dissection to include the posterior hilum, including the left main bronchus and left main pulmonary artery (LMPA) as it enters the posterior major fissure.
   3. Carry this dissection counterclockwise to the superior hilum.
   4. Retract the lung inferiorly to expose the superior hilum, providing access to the posterior side of the LMPA and the aortopulmonary window. Take care not to injure the recurrent laryngeal nerve.
   5. Then, retract the lung posteriorly to expose the anterior hilum using a tightly rolled X-ray detectable gauze sponge.
   6. In a similar fashion, dissect the left superior pulmonary vein (LSPV) and encircle it with a vessel loop by bluntly creating a window behind this vessel with a tips-up grasper, passing one end of the loop in the jaws of the grasper across this window, and grabbing both ends in the grasper to form a loop encircling the vessel.
   7. Divide this vessel by activating and cutting it with the white load robotic stapler to expose the anterior surface of the LMPA.
   8. Proceed with an anterior dissection of the LMPA and encircle it with a tip-up grasper since it is a longer blunt instrument for passing around larger vessels as described above. Then, pass the white-load stapler through and close it, without cutting, while observing the patient's hemodynamics.
   9. Observe the monitor displaying vital signs while communicating with anesthesia colleagues to ensure that hemodynamics remain adequate without hypotension, arrhythmias, and desaturations. Then, activate this white-load stapler to divide the LMPA.
   10. Divide the inferior pulmonary vein next with the white-load stapler. Proceed in this order to prevent engorgement of the lung with venous blood.
   11. Through careful dissection, expose the left main bronchus. Then, clamp the left main bronchus using a green load stapler under intraoperative bronchoscopy to ensure as short a bronchial stump as possible.
   12. Perform an air leak test. With a negative air leak test, harvest a vascularized fat pedicle using tissue from the aorto-pulmonary window to reinforce the bronchial stump with 4-0 interrupted suture.
   13. Using a specimen retrieval bag, remove the specimen through the assistant port location by extending the port incision to ~5 cm, allowing for atraumatic extrication of the specimen.
   14. Undock the robot and close the extrication port with a large absorbable suture, such as 0-PDS or 0-Vicryl suture. Then, close the skin with small absorbable sutures like 4-0 Monocryl suture. Close the remaining port sites at the skin with small absorbable sutures, such as 4-0 Monocryl suture.
       ​NOTE: This concludes the robotic-assisted left pneumonectomy for vanishing lung syndrome.
   15. At the conclusion of the case, perform a toilet bronchoscopy utilizing a full 1,000 mL of Normal Saline.
   16. Routinely place a balancing chest tube to allow for controlled shift of the heart and right lung and to monitor for bleeding. Ensure the tube is never placed to suction.
   17. Ensure that the instrument count is correct at the end of the case by confirming a correct count with the operating room staff.
   18. Ensure that all sharps are disposed in the designated sharps container.
   19. Ensure that the specimen is adequately handled in the designated specimen container and sent off to the pathology laboratory.

Results

The robotic-assisted left pneumonectomy was performed successfully. The patient had an uneventful postoperative course. He was monitored closely for signs of infection, bleeding, or air leak, and all parameters remained stable. The chest tube was removed on postoperative day one, and his diet was advanced. He was discharged home on post-operative day three with nicotine patches and tobacco cessation counseling. Final pathology was negative for incidental malignancy.

Discussion

Surgical intervention, including pneumonectomy, is reserved for patients with severe symptomatic VLS disease that is refractory to medical management. Traditionally, pneumonectomy has been performed via an open thoracotomy and VATS. However, robotic-assisted surgery offers several advantages over traditional techniques, including smaller incisions, improved visualization, and greater precision in tissue handling. These benefits have been particularly useful in the management VLS^6,

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
3-0 Vicryl sutures	Ethicon (Johnson & Johnson)	J683H
30-degree 8mm Endoscope	Intuitive Surgical	470057 (8 mm, 30°)
4-0 Monocryl suture	Ethicon (Johnson & Johnson)	Y494G
4-0 Vicryl Absorbable Sutures	Ethicon (Johnson & Johnson)	J214H
Arm drapes	Intuitive Surgical	470015
Cadiere Forceps	Intuitive Surgical	471049
CO? Insufflation Tubing (Robotic Thoracic)	Intuitive Surgical	470380
Curved bipolar dissector	Intuitive Surgical	471344
Da Vinci Xi Surgical System (robotic cart and console)	Intuitive Surgical	Model IS4000
DERMABOND ADVANCED Topical Skin Adhesive	Ethicon (Johnson & Johnson)	DNX12
Fenestrated Bipolar Forceps	Intuitive Surgical	471205
Mega SutureCut needle driver	Intuitive Surgical	471309
Raytec Cigar Sponge (X-Ray Detectable)	Cardinal Health	23250-407
Specimen Extraction Bag (Large / XL)	Medtronic (Endo Catch™)	173050
SureForm 45 curved-tip stapler (Green)	Intuitive Surgical	480545 (48345G)
SureForm 45 curved-tip stapler (white)	Intuitive Surgical	480545 (48345W)
Tip-Up Fenestrated Grasper	Intuitive Surgical	470347
Umbilical tape	DeRoyal	30-409
White Vessel Loop – Large	Teleflex	34-6010