Final answer:
Severe abdominal pain and signs of severe dehydration or hemodynamic instability in a patient with an intestinal obstruction should be reported immediately, as these can indicate life-threatening complications like bowel perforation or ischemia.
Step-by-step explanation:
When caring for a patient with an intestinal obstruction, nurses must be vigilant for certain acute symptoms that warrant immediate reporting. A critical observation to report would be the sudden onset of severe abdominal pain, which could indicate a bowel perforation or ischemia necessitating urgent medical intervention. Additional critical signs would include signs of severe dehydration, hemodynamic instability such as a rapid heart rate or a drop in blood pressure, and any indications of sepsis, such as fever or a high white blood cell count. Darkening of urine upon standing can also signify dehydration and may be associated with acute kidney injury.