CHAPTER 7 Gastrointestinal System^327
tract to enable the openings of the pancreatic and bile ducts to be seen. A dye is
injected into the ducts through a catheter via the endoscope. X-rays are taken of
the ducts. The patient may report abdominal distention from the insufflation, and
a sore throat.
Before the test—The patient is NPO.
After the test—Monitor vital signs. Assess for return of gag reflex. The patient
remains NPO until gag reflex returns.
Liver Function Tests
These comprise several tests, obtained through a venipuncture, which show hepatic
function. Generally includes alanine aminotransferase (ALT), alkaline phosphatase
(Alk Phos), aspartate aminotransferase (AST), bilirubin, gamma-glutamyl trans-
peptidase (GGPT), lactate dehydrogenase (LDH), prothrombin time (PT), and par-
tial thromboplastin time (PTT).
Alanine Transaminase (ALT)
An enzyme found mainly in liver cells, ALT helps the body metabolize protein.
When the liver is damaged, ALT is released in the bloodstream.
Aspartate Transaminase (AST)
The enzyme AST plays a role in the metabolism of alanine, an amino acid. An
increase in AST levels may indicate liver damage or disease.
Alkaline Phosphatase (ALP)
ALP is an enzyme found in high concentrations in the liver and bile ducts, as well
as some other tissues. Higher-than-normal levels of ALP may indicate liver dam-
age or disease.
Albumin and Total Protein
Levels of albumin—a protein made by the liver—and total protein show how well
the liver is making proteins that the body needs to fight infections and perform
other functions. Lower-than-normal levels may indicate liver damage or disease.