There are no diagnostic laboratory findings associated with ileus. However, laboratory evaluations must be done to identify the severity and presence of other complications of ileus such as electrolyte abnormalities and hypovolemia. Common laboratory test include complete blood count, liver function test, renal function test, serum electrolytes, serum lipase and amylase, arterial blood gas, [Lactic acid|lactate level]], serum albumin and measurement of inflammatory markers.

Laboratory findings in patients of ileus includes^[1][2]

• CBC: It may show anemia, increased total leukocyte count suggestive of infection
• Liver function tests: Deranged LFT may cause ileus
• Renal function test: blood urea nitrogen and creatinin should be evaluated in order to exclude concurrent renal function test in a patient with ileus
• Serum electrolytes: hypokalemia, hypomagnesemia, hypocalcemia and hyponatremia all contribute to muscle paralysis
• Serum lipase and amylase: Acute or chronic pancreatitis may alter gastrointestinal tract function and should be checked to rule out pancreatitis as a cause of ileus
• Serum albumin and prealbumin: To identify the presence of ascites
• Measurements of inflammatory markers such as interleukins 1 and 6 (IL-1, IL-6α) and tumor necrosis factor alpha (TNF-α)
• Arterial blood gas (ABG) and lactate level: To evaluate possible intestinal hypoperfusion and necrosis

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