Critical Care Medicine-Gastrointestinal, Nutrition and Genitourinary Disorders>>>>>Diagnostic and Management Modalities
Question 1#

A 55-year-old male is brought to the intensive care unit (ICU) after an exploratory laparotomy because of a motor vehicle collision where he suffered a liver laceration. He is intubated with an open abdomen and a negative pressure abdominal wound dressing. He remains hypotensive on norepinephrine infusion of 1 µg/kg/min and was transfused 16 units of packed RBCs, 8 units of fresh frozen plasma, 8 packs of platelets, 2 bags of cryoprecipitate. Repeat laboratory tests show a stable hemoglobin postoperatively. However, his urine output starts to decline, and his pressor requirements start to rise. On examination, the abdomen is distended and tight. In the case of intra-abdominal hypertension (IAH), what is the minimum ideal abdominal perfusion pressure (APP) correlating to improved survival? 

A. 90 mm Hg
B. 80 mm Hg
C. 70 mm Hg
D. 60 mm Hg

Correct Answer is D


Correct Answer: D

Patients with an open abdomen and a negative pressure wound dressing can still develop IAH and abdominal compartment syndrome (ACS). Intraabdominal pressure (IAP) of 5 to 7 mm Hg is considered a normal steady state pressure within the abdominal space. Morbidly obese patients may have a higher baseline IAP. APP is calculated as the mean arterial pressure minus the IAP. Studies have showed that an APP of at least 60 mm Hg is correlated with improved survival from IAH and ACS. This resuscitation end point was found to be more important than arterial pH, base deficit, lactate, and hourly urine output in regression model analysis. IAH is defined as IAP greater than or equal to 12 mm Hg. There are four grades of IAH. ACS is defined as IAP greater than or equal to 20 mm Hg with signs of end organ dysfunction. The standard method of measuring IAP is measurement of bladder pressures. Care must be taken to make these measurements with consistent head and body positioning, ideally with a paralyzed patient at end expiration.


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