Intra-Abdominal Pressure Monitoring
Many patients in the critical care setting exhibit increased intra-abdominal pressure (IAP) due to increased fluid or inflammation in the abdominal cavity. If left untreated, this can lead to decreased perfusion to various intra-abdominal organs causing organ dysfunction and failure. Monitoring IAPs can assist with prompt intervention for patients with abdominal compromise.
What Is Normal IAP?
The normal IAP is 0-5 mm Hg. As pressures increase, the abdominal capillaries constrict (they are literally smashed because of the pressure) which causes decreased blood flow to the abdominal organs. As pressures increase, you will start to see both cardiac and renal changes due to the pressure within the abdomen on the major abdominal blood vessels. The kidneys will have decreased blood flow causing decreased urine output and acute kidney damage.
“ Pressures > 13 mmHg may be sufficient to restrict perfusion to the organs of the gut. If the abdominal compartment pressures is between 16-25 mmHg, hypervolemic volume expansion therapy can be used to maintain the perfusion pressure gradient for the abdominal organs. When compartment pressures exceed 25 mmHg, decompression surgery should be considered to prevent organ damage.”
— London Health Science Centre
How To Set Up An Intra-Abdominal Pressure Monitoring System
Setting up your intra-abdominal pressure monitoring system can seem like a daunting task at first, but once you've done it a couple times, it seems fairly logical. The system usually comes as a kit (which makes it all much easier to set up). The only extra supplies I have to grab are a 500 mL normal saline bag and the pressure monitoring cable. The system hooks right into the urinary catheter tubing. This allows you to have an entryway (the bladder) to monitor the abdominal pressures. After setting up the tubing (which the nurse in the video below goes into detail about), you squeeze in 10-20 mL NS into the bladder through the tubing. Make sure to put this into you intake and output charting! Wait for about 20-30 seconds and then the IAP will level off at the true pressure of the abdomen.