title: Negative pressures in surgical drains.
abstract: 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.
mesh_terms: D004322:Drainage; D006801:Humans; D007668:Kidney / Q000601:surgery*; D008954:Models, Biological; D011312:Pressure; D014548:Urinary Fistula / Q000209:etiology; D014556:Urine