Closed system

Digestive: a system not open to the environment; a tube-feeding product where the container is pre-filled with formula so there is no break in the system, potentially giving less cause for bacterial contamination. Respiratory: closed circuit keeps positive pressure; closed suction means tracheal suction system is incorporated into the breathing circuit and does not require disconnection of the breathing circuit thus maintaining respiratory physiology ratios, maintaining PEEP and reducing microbial transmission..