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Thoracic Surgery in the Outram Campus
Thoracic surgery service has been an integral part of the Department of Cardiothoracic Surgery ever since its beginnings and is currently developing separately as a subspecialty of its own. General thoracic surgery has been for several years led by three senior consultants, (one from NHC, and two Visiting Consultants from NCCS). The service offers a comprehensive range of thoracic surgeries ranging from oesophageal resections, tracheal resections and reconstruction to lung transplantation. Weekly thoracic X-ray conferences, journal clubs, tutorials, lung transplant meetings provide updates and training for junior staff .
Minimally invasive thoracic surgery
Minimally invasive thoracic surgery or video-assisted thorascopic surgery (VATS) began early in the 20th century when a surgeon named Jacobeus used a cystoscope to ‘have a look into the chest’.  Such operations took a back seat till the late eighties and nineties when minimally invasive surgery made significant progress in the fields of gynaecology and general surgery. Indeed, much of minimally invasive thoracic surgical techniques are derived from learning through our colleagues of these disciplines. Video thorascopic equipment and dissection instruments (Fig 1) were inherited from general surgery and adapted for use in the chest and this resulted in an exponential increase in 'key-hole' chest surgery.
Figure 1 |
 Whilst most thoracic surgical procedures are performed via the standard incisions (posterolateral thoracotomy or median sternotomy), the National Heart Centre saw a steady rise in videothorascopic surgery (Fig 2) in the last six years. With current equipment and recent introduction of the da Vinci robotic system we are able to offer these techniques for a much wider scope of disease.
Figure 2 |
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Principles of VATS
The use of small caliber but high resolution video equipment enables the surgeon to visualise the entire chest cavity carefully and thoroughly.
Dissection with small and long newly developed surgical instruments is a learnt process that every VATS surgeon has to undergo. Thoracic surgeons performing VATS have to compensate for the lack of tactile sensation accorded in open techniques. To overcome this, utmost care is needed when dissecting around pulmonary vessels and the heart.
Adopting the principle of ‘triangulation’ where a central port is used for the videoscope, the other ports, up to three, are placed in appropriate positions forming a triangle or pyramidal formation (after visualising the pleural cavity). This allows maximal mobilisation in the thoracic cavity without the tips of the dissectors clashing with each other.
To facilitate dissection for the surgeon and the assistant, two video panels are used on either side of the patient (Fig 3).
Utility incision - this is a larger incision which is made at the end of surgery to allow delivery of the mass or lobe. No rib spreader is used reducing postoperative pain. (Fig 3)
Figure 3 |
Anaesthesia
Double lumen intubation during general anaesthesia is required for the performance of video assisted thorascopic surgery. This technique separates the ventilation of the opposite lung whilst allowing collapse of the ipsilateral lung. This facilitates placement of the video scope and instruments. Visualisation of the thoracic cavity would not be obstructed if the ipsilateral lung is well collapsed. Occasionally carbon dioxide insufflation is used to promote lung collapse on the ipsilateral side. Epidural anaesthesia is preferred for post op pain control. Intravenous morphine via patient control analgesia pump is an acceptable alternative. |
| TABLE 1 - Common Indications for Diagnostic VATS |
TABLE 2 - Common Indications for Therapeutic VATS |
TABLE 3 - Expanded Indications for Therapeutic VATS |
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• Undiagnosed pleural effusion
• Interstitial lung disease
• Indeterminate lung nodule
• Mediastinal staging and biopsy
• Evaluation of pericardial disease
• Trauma |
• VATS pleurodesis
- Recurrent pneumothorax
- Malignant pleural effusion
• VATS sympathectomy
• VATS drainage of empyema |
• Thymectomy
• Lobectomy
• Esophagectomy
• Excision of mediastinal tumours
• Spinal reconstruction for scoliosis
• Repair of pectus excavatum
• Lung volume reduction surgery |
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Indications for VATS
Broadly minimal invasive thoracic surgery can be divided into diagnostic and therapeutic VATS procedures. The list of indications is currently expanding as surgeons become more familiar with the latest equipment (Table 1, 2, 3).
Contraindications to VATS
Previous thoracotomy and dense adhesions are relative contraindications to VATS. Large tumours of the thorax with diffi cult mobilisation may not be amenable to keyhole surgery.
Benefits of VATS
With small (5 to 12 mm) incisions instead of larger thoracotomy incisions, patients benefit from less chest wall trauma, less pain, shorter recovery, early discharge and early return to work.
Expanding Scope of VATS
Aside from the regular indications, VATS lobectomy, oesophagectomy, thymectomy are gaining popularity among thoracic surgeons worldwide.
VATS lobectomy is currently performed for small lung cancers safely. Mediastinal lymph node dissections with VATS conform to current standards of lymph node staging. When applied together, early cancer of the lung can be resected with equivalent results as open techniques. This benefits a wider range of patients with comorbidities whom may not be candidates for open surgery. VATS thymectomy (instead of sternotomy) for myasthenia gravis performed from the side (usually the right) is a more acceptable operation for patients and referring neurologists both cosmetically while achieving similar results in the short to medium term.
Both of these are currently performed at the NHC and NCCS. Although VATS esophagectomy is advocated in the west as a possible surgical technique, we have not found this possible as local oesophageal cancers usually appears in the mid chest and are locally advanced thereby not amenable to VATS. Future uses of VATS include correction of pectus excavatum and correction of scoliosis. |
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Robotics Assisted Thoracic Surgery
There are, however, several limitations to the use of VATS.  Video technology is still in two-dimensional mode and there is restriction of mobility at the tips of our VATS instruments. Instruments introduced through the chest wall are manipulated such that the entry point in the chest acts as a fulcrum and movements become counter intuitive.
The da Vinci robotic system consists of an ergonomic surgeon’s console, a patientside cart with four interactive robotic arms, a binocular vision system and multi joint EndoWrist instruments (Fig 4a, b, c).  Figure 4a, b & c
Computer algorithms of the da Vinci filters out tremors and translates the surgeon’s hand movements into more precise movements of the EndoWrist (Fig 5) instruments. EndoWrist instrument tips can rotate like the human wrist, allowing complex dissection or reconstructive surgery in the closed chest allowing the surgeons to draw on the same techniques learned in open surgery to be performed via small incisions.
Motion scaling of 2:1 to 5:1 allows small movements made at the console to be magnified at the patient end.
Figure 5
With the patient in a lateral position, ports are placed to allow the robotic videoscope, and three other working 10mm ports for the robotic instruments. A bedside surgeon assists in traction and changing of instruments whilst another performs the operation at the console (Fig 6). The video system of the da Vinci magnifies the visual field provides excellent visualisation of the planes for dissection.
Figure 6
We are still in the early phase of developing this field. Only two patients have undergone surgery via the da Vinci thus far. Limitations are due to its excessive costs. With new funding available for subsidies, we are sure of wider application of robotic technology in thoracic surgery. | |
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