Robot-Assisted Left Upper Lobe Lung Volume Reduction Surgery With Intraoperative Firefly Perfusion Assessment

The authors demonstrate a robot-assisted lung volume reduction surgery (LVRS), performed for a 71-year-old man who was an ex-smoker with severe chronic obstructive pulmonary disease (COPD) (FEV₁, 0.68 L or 22%; DLCO, 51%; MRC Dyspnea scale, 4). Extensive preoperative investigation included high resolution computed tomography with StratX lung report, bronchoscopy with Chartis balloon pressure assessment, transesophageal echocardiography, right and left cardiac catheterization, and cardiac magnetic resonance imaging. Following discussion at a National COPD LVRS multidisciplinary meeting, the decision was made to proceed with surgery.

After induction of general anesthesia, a double-lumen endotracheal tube was sited to facilitate single-lung ventilation. The patient was placed in the right lateral decubitus position. An ultrasound-guided interfascial serratus plane block was performed with long-acting local anesthetic prior to the procedure, providing good postoperative analgesia of the hemithorax.

The da Vinci Xi robotic platform was used. This system facilitates CO₂ insufflation (the less emphysematous lung with less air trapping tends to preferentially deflate first), 8 mm port hopping with a 30 degree tridimensional robotic camera, and closed robotic stapling of the lung parenchyma using a 12 mm port, with minimal disruption to the intercostal space and intercostal nerve. This limits acute and chronic pain and obviates the need for spinal epidural analgesia regimens. Three ports are used, two 8 mm and one anterior 12 mm port. The first port to be placed is the 8 mm camera port, inserted slightly anterior to the scapular tip. For the da Vinci Xi system, the distance between the ports should be 4 cm at a minimum. This facilitates optimal manipulation of the instruments within the chest cavity. The authors endeavor whenever possible to keep all three ports in the same intercostal space in order to limit postoperative pain.

The first intraoperative step was a thorough evaluation of the entire lung, looking for any significant bullae or blebs. Given that the da Vinci system does not provide tactile feedback to the operator, it is vital that the surgeon’s instruments are always under view in the chest to minimize the risk of iatrogenic injury.

The authors then proceeded to the perfusion assessment. The da Vinci Firefly system involves the injection of indocyanine green (ICG) tracer into the blood, which is then detected using near-infrared imaging. Dilute 1 ampoule (25 mg) of Verdye (ICG) with 10 ml water for injection to give a 2.5 mg/ml solution. Administer the ICG in a 3 ml bolus and repeat as necessary, to an upper limit of 0.3 mg/kg. ICG is confined to the vascular system, has a half-life of 3-4 minutes, and is eliminated by the liver (1). The system allows for real-time intraoperative assessment of pulmonary perfusion, with ICG detectable in the lung parenchyma within seconds following injection, thus guiding resection. In this patient, the lingua demonstrated comparatively good perfusion, and therefore the targeted resection avoided this area entirely.

The final operative step was the resection. A significant advantage of the da Vinci Xi system is that it allows for robotic stapling using the EndoWrist 30 mm or 45 mm stapler, reducing tremor and improving dexterity due to fully wristed articulation and SmartClamp feedback. This stapler has the greatest side-to-side articulation currently available, with a range of 108 degrees total side-to-side and 54 degrees total up-and-down. This contributes greatly to the efficiency of the procedure, maintaining the contour of the lung in a limited operative field and minimizing the risk of postoperative air leak.

References

1. Lue JR, Pyrzak A, Allen J. Improving accuracy of intraoperative diagnosis of endometriosis: role of firefly in minimal access robotic surgery. J Minim Access Surg. 2016;12(2):186-189.