A 45-year-old male was admitted to the intensive care unit (ICU) 2 days ago with a diagnosis of acute pancreatitis secondary to alcohol abuse. After initial resuscitation with large volume isotonic crystalloid solution for persistent hypotension, he developed worsening pulmonary edema with an increased oxygen requirement ultimately requiring intubation. In addition to Acute Respiratory Distress Syndrome, another potential complication seen in severe pancreatitis requiring large volume resuscitation is abdominal compartment syndrome. All of the following are signs/symptoms of abdominal compartment syndrome EXCEPT:A. Intra-abdominal pressure = 10 mm Hg
Correct Answer: A
Abdominal compartment syndrome (ACS) is defined as end organ dysfunction related to sustained intra-abdominal hypertension (IAH). The average intra-abdominal pressure in critically ill patients is 5 to 7 mm Hg, not including patients with obesity or pregnancy, which may predispose them to slightly higher baseline pressures. IAH is defined as sustained pressures >12 mm Hg and is further subdivided into Grades I-IV based on escalating pressure intervals. ACS is defined as sustained IAH with new IAH-induced organ dysfunction, which includes increased peak inspiratory and mean airway pressures leading to alveolar barotrauma, renal impairment both from renal vein compression and renal artery vasoconstriction, decreased cardiac output secondary to cardiac compression and decreased venous return, and decreased mesenteric perfusion causing intestinal mucosal ischemia. There is no set intraabdominal pressure that defines ACS, but sustained intra-abdominal pressures >20 mm Hg is typically required to cause the physiologic disturbances described above. Because of these relatively high pressures, these patients present with a tense and distended abdomen (Answer B). Although intra-abdominal compartment pressures can be measured through a number of indirect methods (intragastric, intracolonic, inferior vena cava), the standard method is intravesicular via a foley catheter.