Mediastinal lymph node dissection in open thoracic surgery

Abstract

Nodal staging is well established in management of lung cancer. Hence, any lung resection should be combined with dissection of at least 3 nodal stations. Open access is gained via thoracotomy. The lymphadenectomy should precede lung resection. Station 2 is dissected by extending the planes from Station 4 superiorly. The left side demands special maneuvers and remains challenging. The recurrent nerve should be protected and therefore diathermy needs to be avoided in this position. Station 4 is routinely dissected on right side and rarely on left. Trachea, azygos vein and superior vena cava (SVC) define the dissection triangle. Special attention is required to tributaries from SVC and aberrant chyle duct branches to avoid complications when dissecting this nodal station. Station 5 is defined by the arch and main pulmonary artery roof. The commonest complication is recurrent nerve injury; hence, dissection should be gentle with no use of diathermy at the proximity of the vagus nerve close to the arch. Lateral dissection towards the arch, offers access to Station 6. Attention should be exercised to avoid injury to an aberrant superior intercostal vein. Station 7 becomes evident following the main bronchus to the carinal origin. Main attention to bronchial arteries should be exercised at the floor of the carina or descending aorta tributaries on the left to avoid disturbing bleeding. Clips and not diathermy should be used. Moderate bleeding is managed with packing and patience. Station 8 lies adjacent to esophagus. Gentle dissection is required to avoid esophageal and thoracic duct injuries. Station 9 is contained in the inferior pulmonary ligament and is dissected at hilar mobilisation. Attention to fat pad mediastinal vessel is mandatory.