A wound heals through several processes including bleeding and scabbing. It's normal for a wound to show minimal to moderate drainage within the first week.

However, if there are pustules or thickened, discolored drainage, particularly in large amounts, this could indicate an infection. This infection can be avoided by undergoing after-surgical drainage treatment. You must schedule an appointment with your surgeon to undergo this treatment.

Since the 1960s, drains have been used in surgery to remove fluids from the body. This prevents serious fluid accumulation and improves wound healing. Drainage systems are used after surgery to drain fluid (mostly blood) from surgical wounds. Depending on the purpose of the drain, they can be either closed or open and active or passive.

Closed systems use a vacuum system for fluid withdrawal and then collect the drainage into a reservoir. Vacuum drains that are closed use negative suction to create a vacuum environment and promote healing. Closed vacuum drains must be empty and measured at the end of each shift.

You should inspect the drainage site periodically for leakage and ensure that it is properly covered with a sterile dressing. 

Closed wound drainage systems are designed to allow enough moisture to remain in tissues to promote regeneration and lessen inflammation while removing excess exudate or material that may hamper the healing process.