I have done IAP (intra abdominal pressure) monitoring where I work. Normal pressures are around 10-15, 15-20, start thinking about an intervention or find the source and fix it, etc, >20 consider surgical intervention. I have witnessed the abdomen to be re-opend because of compartment syndrome. The patient went to OR and returned with a "belly in a bag". (Unable to close the fat and skin until the patient shrinks down a bit, so they wrap the opened belly with ioban and sterile towels to support the guts). :-)
Set up a transducer to pressure bag etc.
(only use 0.9% normal saline as the flush solution, no heparin!!!!!!)
attatch a 60cc with sterile saline and needle. (yes, becareful!). put the needle into the aspirate port of the foley after cleaning it of course. Clamp the foley about an inch below the port, fill the tube with the sterile saline. (manipulate stopecock to gently push about 20cc of sterile sailine. goal is to have the from the clamped part of the foley to the bladder filled with saline and no bubbles).
then zero the monitor, holding the transducer close to the bladder/abd. area as close as possible. make sure no airbubbles in foley or transducer. when it is zeroed, then trace the wave form for about a minute and get your reading.
usual duration of checking can be every hour.
don't forget to unclamp the foley and safely rid the needle! keep everything as sterile/aseptic as possible.
just a run down on how to do it. Others may do it differently, not sure about that though.
it is a very useful intervention of the critically ill after surgery!
hope this helps.