Presentation Description / Summary: Abdominal perfusion pressure (APP), the difference between the mean arterial pressure (MAP) and the intra-abdominal pressure (IAP), is the pressure gradient that dictates blood flow to organs. As normal IAP is usually minimal (0 - 5 mmHg), MAP is typically the surrogate marker for APP. However, sustained increases in IAP > 12 mmHg can lead to intra-abdominal hypertension (IAH) and subsequent decreases in APP and organ perfusion. When the IAP exceeds 20 mmHg and is associated with organ dysfunction, abdominal compartment syndrome (ACS) develops. This continuum of rising IAP leads to central nervous system, cardiovascular, pulmonary, gastrointestinal, and renal dysfunction. Conditions associated with decreased abdominal wall compliance, increased intraluminal contents, and/or increased extraluminal contents can lead to increased IAP in our patients. Therfore, patients with abdominal pain, ileus, intestinal obstruction, intra-abdominal masses, organomegaly, ascites, constipation, or following endoscopic/laparoscopic procedures all have risk factors for developing IAH. Therefore, understanding the pathophysiology of how IAH develops, how to measure IAP, and the consequences of IAH and compartment syndrome, is paramount to our ability to manage it appropriately. Treatment guidelines are dictated by the etiology and severity of the IAH and include medical and surgical intervention.
Learning Objectives:
Define abdominal perfusion pressure (APP), intra-abdominal pressure (IAP), intra-abdominal hypertension (IAH), and abdominal compartment syndrome (ACS). What factors contribute to intra-abdominal pressure (IAP) and what clinical scenarios are commonly and experimentally implicated in the development of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS)?
Describe how IAP is measured and IAH/ACS diagnosed. Describe the physiologic consequences of IAH on organ perfusion and function.
List the current guidelines in the management of IAH/ACS and what prophylactic and therapeutic interventions are available and recommended for our patients?
