A case of spontaneous pnemothorax comes to you . What will be the earliest treatment of choice

"Open Pneumothorax is one in which full thickness segment of the chest wall has been destroyed and the negative intrapleural pressure sucks air directly through the chest wall defect rather than through the trachea into the alveoli. It occurs most commonly after shotgun blasts explosion with flying debris. The pt. is stabilized by any mechanical covering over the open wound. As soon as convenient a wateight dressing should be placed and an intercostal catheter inseed into the pleural cavity. Early debridement and formal closure of the wound should then be performed." Ref : Schwaz, 7/e p684