when evaluating a patient with constipation in the hospital you want to be sure that you don't confuse constipation with a more serious condition like bowel obstruction constipation is a common symptom in both small and large bowel obstruction blindly treating constipation without being sure the patient does not have a bowel obstruction can be dangerous and lead to bowel perforation patients with bowel obstruction often have more symptoms than just constipation they may also have abdominal pain nausea and vomiting and abdominal distension usually the constipation develops acutely other key elements in the history can help you here you want to ask about risk factors for developing a bowel obstruction like history of prior abdominal surgeries history of crohn's disease prior abdominal radiation intra-abdominal cancer among many others on physical exam patients with bowel obstruction tend to look sicker than those with constipation they may have signs of dehydration or sepsis depending on the severity of the obstruction on abdominal exam with obstruction you would expect to find distension and often tenderness to palpation although the location of tenderness does not correlate well with the area of obstruction the typical finding on auscultation is high pitched hyperactive bowel sounds as the bowel muscles attempt to push material past the obstruction this is not always the case patients can also have hypoactive or absent vowel sounds with obstruction and of course you want to look for peritoneal signs on exam that warrant emergent surgical intervention such as rebound tenderness involuntary guarding and abdominal rigidity these findings may help but in clinical practice sometimes the history and physical exam cannot fully distinguish between constipation and bowel obstruction the differential diagnosis can still include things like post-operative or medication-induced ileas or colonic pseudo-obstruction if you still find yourself concerned for a bowel obstruction imaging can be helpful to differentiate between these diagnoses an abdominal x-ray or ct scan can help you look for signs of bowel obstruction on x-ray you might see air fluid levels and dilated loops of bowel in an obstruction intraperitoneal free air indicating bowel perforation is the most feared finding on x-ray in a bowel obstruction x-rays are most helpful here when you get at least two views on an abdominal x-ray one in a dependent position such as supine and one in a non-dependent position meaning upright or decubitus a ct is more sensitive and should be done on all patients in whom you suspect small bowel obstruction or sbo it can show you dilated bowel loops with air fluid levels help you find the underlying etiology localize a transition point between dilated and collapsed bowel as shown here and help you distinguish between high or low grade obstructions it can also help you look for feared complications like bowel ischemia necrosis or perforation you would not see a transition point in ilias or constipation just dilated bowel loops with stool and air throughout now when you are evaluating a patient with constipation you know what signs and symptoms to look for to rule out a bowel obstruction equivocal cases where you feel like you don't have enough information based on your history physical exam and labs imaging can be helpful so i hope you liked this video absolutely make sure to check out the course this video was taken from and to register for a free trial account which will give you access to selected chapters of the course if you want to learn how medmastery can help you become a great clinician make sure to watch the about my mastery video so thanks for watching and i hope to see you again soon