NURSING PATIENT CARE POLICY & PROCEDURE
November 25, 2015
Nursing Manual (Red)
Policy #: 1.43
Title: Intra-Abdominal Pressure Monitoring
Intra-abdominal pressure (IAP) measurement (bladder pressure) is indicated in
patients who are at risk for the development of intra-abdominal hypertension (IAH) or
abdominal compartment syndrome (ACS).
A urinary catheter with a closed drainage system is required to obtain bladder
III. GENERAL INFORMATION
IAH and ACS result when the abdominal contents expand in excess of the capacity of
the abdominal cavity. IAH is defined by a sustained or repeated IAP of 12 mmHg or
greater. ACS is defined as a sustained IAP > 20 mmHg that is associated with new
organ dysfunction/failure. For children IAP is defined as greater than 10 mmHg with
evidence of new organ dysfunction or failure. IAP measurements should be
correlated with findings on physical assessment. For adults, normal IAP is between 5-
7mmHg. For children, normal IAP value is 4-10.
IAH occurs in approximately 50% of intensive care adult patients and ACS has a
mortality rate of 50-75%, so early identification is essential (Chen et al., 2015). The
incidence of IAH in pediatric patients is believed to be underrecognized and thus
underreported. It is recommended by the World Society of Abdominal Compartment
Syndrome (WSACS) monitoring IAP if a patient has 2 or more risk factors for IAH
IAP measurement may be contraindicated in certain conditions, such as bladder
trauma, bladder surgery, and neurogenic bladder. Discuss with ordering provider
prior to performing in these patients.
A. Cardiac monitor and pressure cable for transducer
B. 500 or 1000 mL IV bag of normal saline solution
C. Pressure bag (sleeve) for adult patients
D. Pressure transducer system
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F. 30 mL Luer-Lok syringe
H. 2% chlorhexidine applicator
A. Set up and flush disposable pressure transducer and continuous flow tubing
system, adding one stopcock distal to the existing stopcock (Figure 1), making
sure to maintain sterility of system.
1. Spike the bag of normal saline IV solution and place in pressure sleeve
(do not use a pressure bag for pediatric patients). The sleeve should not
be pressurized at this time as this can cause air bubbles to form in the
tubing or transducer.
2. Prime the tubing and all stopcocks: flush the tubing and transducer by
activating the fast-flush mechanism (pulling the red rubber pigtail or
squeezing the two white clips) until the flush solution flows out through
the white vented cap on the stopcock distal to the transducer. NOTE:
Rapid flushing/filling of tubing contributes to air bubble formation.
Make sure all air bubbles have been expelled. The presence of air
bubbles in the transducer or tubing may cause inaccurate pressure
3. Replace the vented white caps with dead-end caps. These are provided
in the tubing package.
4. Pressurize sleeve to 300 mm Hg (adult only).
Figure 1. Bladder pressure monitoring set-up. (From
http://www.generalsurgeonslinks.com/trauma.critical.care.html.) Used with
Note: Use Luer-Lok end of transducer set-up to connect to Luer-Lok sampling port
on urinary drainage system (Step G), not angiocath, as indicated in picture above.
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B. Connect monitor cable to transducer.
C. Ensure that the patient is in the supine position, if possible. Head of bed elevation
significantly increases IAP compared to supine positioning. Document patient
positioning during measurement for consistency among measurements.
D. Level the zeroing stopcock to the mid-axillary line at the superior iliac crest.
E. Zero the transducer. (Zeroing the transducer equalizes the transducer to
atmospheric pressure and gives an accurate known reference point). Re-zero a
minimum of every 8 hours.
1. Turn off the alarm.
2. Open the transducer to air by turning stopcock to an off position to the
patient and removing the cap from that stopcock.
3. Touch ‘zero’ button on module or touch ‘parameter’ key, select correct
pressure, then select zero. Monitor will indicate when zero is complete.
If the system does not zero, check all stopcocks, connections, and
reattempt zeroing. The transducer may need to be changed, or an
alternate pressure channel used on the monitor (if available) if still
unable to zero.
F. Clamp the bladder drainage system just distal to the catheter and drainage bag
connection with a hemostat.
G. Cleanse the sampling port on the urinary drainage system with chlorhexidine and
attach the Luer-Lok end of the transducer set-up to the Luer-Lok sampling port on
the urinary drainage system.
H. Attach the 30 mL syringe to the distal stopcock of the transducer. Turn the
stopcock attached to the syringe off to the patient and open to the pressure bag
(adult patients) saline bag (pediatric patients) and syringe. If pressure bag (adult
patients), saline bag (pediatric patients) has a clamp check that the clamp is open,
withdraw saline into the syringe. For pediatric patients with draw up 1 mL/kg up
to 20kg. For patients over 20 kg and adults draw up a maximum 25 mL. Turn the
stopcock off to the pressure bag (adult) saline bag (pediatric) and open to the
syringe and patient. Inject the normal saline into the bladder. Expel any air seen
between the clamp and the urinary catheter by opening the clamp and allowing
the saline to flow back past the clamp; then re-clamp as air in the system may
dampen the pressure reading.
I. Measure IAP 30-50 seconds after instillation to allow bladder detrusor muscle
relaxation. Transducer should be placed at the mid-axillary line at the superior
iliac crest. Measure in the absence of active abdominal muscle contractions.
J. Print a strip of the waveform and measure the IAP at end expiration. IAP should
not be determined from the numeric display on the monitor, as this reflects a
mean pressure value, rather than just the expiratory IAP.
1. For ventilated patients, end expiration is measured at the valley of the
2. For non-ventilated patients, end expiration is measured at the peak of the
K. Once a reading has been obtained, unclamp the drainage system to restore urine
drainage. Leave the transducer in the sampling port to prevent repeated breaks in
the system. Although the transducer system remains in place, bladder pressures
cannot be continuously measured. Monitoring requires clamping the drainage
system and filling the bladder to obtain a reading (steps E-L).
L. Document the bladder pressure and volume of saline infused.
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M. Serial measurements of bladder pressure are recommended, at least every 2 to 4
hours or more frequently, depending upon physician order and clinical need.
A. AACN (2011). AACN Procedure Manual for Critical Care (6th Ed.). Philadelphia,
PA: WB Saunders Co.
B. Cheatham, M. L, Malbrain, M. L., Kirkpatrick, A., Sugrue, M., Parr, M.,
DeWaele, J., Balogh, & et al. (2007). Results from the international conference of
experts on intra-abdominal hypertension and abdominal compartment syndrome.
II. recommendations. Intensive Care Med, 33(6), 951-962.
C. Chen, Yuan-zhuo; Yan, Shu-ying; Zhuang, Yu-gang; Wei, Zhao; Shao, Wei
& Peng, Hu. (2015). Noninvasive monitoring of intra-abdominal pressure by
measuring abdominal wall tension. World J Emerg Med, 6(2), 137-141.
D. Ejike, J. C., Bahjri, K., & Mathur, M. (2008). What is the normal intra-abdominal
pressure in critically ill children and how should we measure? Crit Care Med,
E. Koehl Lee, R. (2012). Intra-abdominal hypertension and abdominal compartment
syndrome: a comprehensive overview. Crit Care Nurse, 32, 19-31. Doi:
F. Newcombe, J; Mathur, M, Ejike, J.C (2012) Abdominal compartment syndrome
in children. Critical Care Nurse 32 (6), 51-60.
VII. REVIEWED BY
Clinical Nurse Specialist, Burn Center & Surgical Trauma Unit
Clinical Nurse Specialist, Cardiac Surgery
Clinical Nurse Specialist, Thoracic Surgery
Clinical Nurse Specialist, AFCH PICU
Clinical Nurse Specialist, Trauma Life Support Center
Nursing Patient Care Policy and Procedure Committee, November 2015
Beth Houlahan, DNP, RN, CENP
Senior Vice President Patient Care Services, Chief Nursing Officer