Urology & Urogynecology > Education and Reference

CATHETER SETUP:

1. Remove the abdominal pressure catheter from the package and uncap both lumen extensions.
2. Place a Four-Way stopcock (e.g. a Life-Tech "4-SC") on the shorter lumen extension labeled "FILL/PABD."
3. Fill a 5cc syringe with water and place it on the Four-Way stopcock as shown in the figure to the right.
4. This step is easily accomplished with the catheter held so that the balloon is pointed upward. Using the syringe, infuse water into the catheter. This action forces the air inside to rise and then discharge out of the lumen extension labeled "PURGE ONLY."
5. After all the air has been flushed through the balloon and catheter, close the cap on the lumen extension labeled "PURGE ONLY."
6. Collapse the balloon by withdrawing the water from the catheter with the syringe.
7. Turn the Four-Way stopcock to the OFF position as shown in the figure to the right. The abdominal catheter is ready for the patient.

PATIENT SETUP:

1. Place the catheter in the patient's rectum or vagina and tape it in place.
2. Open the stopcock and infuse approximately 1-1.5cc of water into the balloon with the syringe. Then, turn the Four-Way stopcock to the OFF position as shown in the figure to the right.
3. Connect the P2 (abdominal) Pressure Transducer tubing to the Four-Way stopcock as shown.
4. Turn the Four-Way stopcock OFF to the syringe and ON to the P2 Pressure Transducer and catheter. Next, observe the pressure waveforms on the channels recording pabd (abdominal pressure) and pdet (detrusor pressure).
• NOTE: At the beginning of a CMG, when the bladder is (presumably) empty, it is recommended that the starting pdet (detrusor) pressure be "0" cm H20. To achieve this value, pabd (abdominal pressure) must equal pves (vesical) pressure (pdet=pves-pabd).
5. To change the pdet value, open the stopcock and (a) add water to lower it or (b) remove water to raise it. This is done with the Four-Way stopcock turned so that all three ports are open. Then you can view the pressure changes while adjusting the water content of the balloon. When finished, turn the stopcock so that it is OFF to the syringe as it was initially. Remember, adding water decreases pdet (increases pabd) and removing water increases pdet (decreases pabd).

CATHETER SETUP:

1. Remove the ERPC-9 (abdominal pressure catheter) from the package and place a four-way stopcock (e.g. a Life-Tech 4-SC) on the catheter luer connector as illustrated.
2. Fill a 10cc syringe with 5-7cc of water, place it on the four-way stopcock, and open the stopcock between the syringe and catheter.
3. Holding the assembly as illustrated, with the balloon pointing up and the syringe luer-down, aspirate all air from the balloon into the syringe (it will rise above the water in the syringe barrel).  Create a vacuum in the catheter.
4. Inject water until the water level in the balloon has risen above the tip of the catheter (the balloon will be slightly distended at this point), then
5. Aspirate until the balloon has completely collapsed.  This should evacuate most of the air from the balloon into the syringe.
6. Repeat steps 4 & 5 until no air is present.  Finish the preparation with the balloon collapsed and the stopcock in the OFF position as illustrated. The abdominal catheter is ready for insertion in the patient.
7. If desired, disconnect the syringe, eject the air that was aspirated and reattach, being careful to not introduce an air bubble into the luer connector.

PATIENT SETUP:

1. Insert the catheter 12-14cm into the patient's rectum (or vagina, if preferred).
2. Open the stopcock and infuse approximately 1-1.5ml of water into the balloon with the syringe. Then, turn the four-way stopcock to the OFF position as illustrated.  The syringe can be removed if desired
3. Tape the catheter securely in place, using about a 36cm length of 10mm wide paper tape.  Fashion a sling by taping from the sacrum, between the buttocks, across the rectum (trapping the catheter), then forward along the crease of the perineum and upper thigh.  This technique works best if the catheter is placed rectally.
4. Slowly, open the stopcock between the catheter and the luer connector to be used for pressure tubing connection. As fluid fills the luer and forms a meniscus, quickly connect the tubing and stopcock as shown (take care that you do not lose much fluid from the balloon).
5. Observe the pressure waveforms on the channels recording pves, pabd, and pdet.
• NOTE: At the beginning of a CMG, when the bladder is (presumably) empty, it is recommended that the detrusor pressure (pdet) be 0cm H20. To achieve this value, abdominal pressure must equal vesical pressure (pdet = pves - pabd).
6. If pabd is higher than pves, slowly open the stopcock to the free luer connector and allow a drop of fluid to escape.  Repeat until pabd equals pves.
   1. If pabd is lower than pves, use the syringe as illustrated, with all stopcock ports open, to add a few drops of water until pabd equals pves.
   2. When pves and pabd are equal, pdet will be 0cm H20. Turn off the stopcock to the syringe, remove the syringe and have the patient cough to verify continuity and good pressure transmission.
7. Begin the study.