What happens after a bed sore bursts?

Not typical too late: If a bed sore has burst, most likely it is too late for preventive care. Typically the surface of a pressure sore is the tip of the iceberg and once it has "ruptured" extensive tissue death has occurred beneath the surface causing liquefaction necrosis. At this point more adequate drainage and surgical debridement of dead tissue is recommended with care to minimize subsequent pressure.

High risk infection: This can result in very serious infection. Proper treatment needs to be started, avoiding further pressure on that site. If an infection set in, it could spread thru the bloodstream resulting in sepsis which could be deadly.