Negative Pressures in Surgical Drains.

- Laboratory and clinical experiments were done to measure the pressure in tube drains. It was found that the fluid in drains connected to floor bags exerted a negative pressure equal to the height of the fluid column in the tube. There was no negative pressure when the drain opened into a urostomy bag at wound level. It is suggested that this negative pressure might tend to maintain a urinary fistula once a leak in the suture line has begun. [ABSTRACT FROM AUTHOR]