A low-cost and simple-to-use system and method to facilitate a prophylactic pleural lavage protocol at the time of thoracostomy tube placement for traumatic hemothorax in order to reduce the need for secondary intervention for the management of retained hemothorax. The invention may be used in conjunction with existing chest tubes and be administered at the time of initial chest tube placement, and continued at the bedside (by a bedside nurse) over the duration of chest drainage, as necessary. The system includes an operator device that semi-automatically administers a pleural lavage protocol consisting of saline instillation, and suction to slow the clotting process, prevent “gelling” of blood, and maintain drainability.