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Free vastus lateralis muscle flap transplantation for postoperative chronic empyema: retrospective analysis of eight case series.

BACKGROUND
Postoperative chronic empyema (PPE) remains a complex challenge for thoracic surgeons. We retrospectively investigated patients with PPE who were treated with free vastus lateralis muscle flap transplantation, and report our results.


METHODS
Eight patients with PPE and persistent bronchopleural fistula (BPF) treated in our hospital from January 2015 to June 2019 were retrospectively analyzed, the time since onset of empyema ranged from 5 to 72 months. The operation was performed in two stages, stage I surgery included empyema debridement, rib resection drainage or open-window thoracostomy (OWT), meanwhile, BPF was treated under bronchoscope. Stage II surgery included obliteration of the pleural space by free muscle flap transplantation. The keys to the operation are thorough debridement, closure of the BPF, and complete obliteration of the residual pleural space. The challenge lies in the anastomosis of the lateral femoral circumflex artery and vein that supply the vastus lateralis muscle flap to the thoracodorsal vessels.


RESULTS
The free muscle flaps survived in all eight patients. The abscess cavity was completely obliterated with the muscle flap. Good efficacy was achieved with primary wound healing. No serious perioperative complications were reported. No empyema recurrence, atrophy, infection, or necrosis of the muscle flap was seen during the 18- to 72-month follow-up.


CONCLUSIONS
The vastus lateralis muscle flap has a large volume with good blood supply and strong antibacterial ability. It can be used for effective obliteration of a large residual cavity caused by empyema and maintains a good thoracic shape. It is an ideal choice for the treatment of postoperative chronic refractory empyema.