General surgery Flashcards
Water soluble contrast challenge
The water-soluble contrast medium challenge is a diagnostic and therapeutic tool used in the management of patients with adhesive small bowel obstruction. This challenge involves administration of water-soluble contrast medium (Gastrografin or diatrizoate meglumine) and subsequent evaluation of contrast within the colon in 4-24 hours with an abdominal x-ray. A WSCM “meal” of 50-150 ml should be given at the time of initial CT or shortly after. This can be given orally or through an NGT. If an NGT is used, contrast should be given after 1-2 hours of gastric decompression, and the NGT should be clamped for 4 hours after administration. If there is no contrast seen within the colon, the patient is unlikely to resolve their small bowel obstruction with conservative management and should undergo adhesiolysis. Level 1a evidence supports the use of the WSCM for adhesive SBOs with studies showing both a high sensitivity and specificity. Additionally, the WSCM has been shown to have a cathartic effect on bowel function with decreased time until resolution of small bowel obstructions.
What are the most common causes of lower GI bleeding in the adult population?
The most common causes of acute LGI hemorrhage are diverticulosis (24% to 47%), colitis (6% to 26%), neoplasms (9% to 17%), and angiodysplasia (2% to 12%).
