A1-month-old female presents after an episode of bilious emesis. She became irritable 12 hours ago, began vomiting 6 hours ago, and is now lethargic. She had one small stool that was somewhat bloody 2 hours ago.Which of the following statements is true?
Answer(s): A
Any infant or child that presents with bilious emesis should be evaluated immediately for malrotation with midgut volvulus. This is a surgical emergency since the volvulus can compromise the vascular supply to the intestine. Malrotation is a congenital disorder wherein the normal prenatal rotation of the midgut is incomplete and results in the cecum remaining in the epigastrium with a narrow superior mesenteric artery (SMA) pedicle. When this happens, bands form between the cecum and the abdominal wall ("Ladd's bands"). Avolvulus may result around the shortened mesentery, cutting off the vascular supply to the midgut and causing obstruction. In volvulus, patients present with acute onset of bilious emesis and later with bloody stools or hemodynamic instability. The diagnosis of malrotation can be best made with an upper GI contrast study, which will show the duodenojejunal junction displaced to the right of midline. Sometimes this can also reveal volvulus. Patients with volvulus must be taken emergently to the OR to reduce the volvulus. If intestinal ischemia is advanced, a significant portion of small bowel may have to be removed, resulting in "short gut syndrome." In this patient presenting with bilious emesis, malrotation with volvulus must be considered and addressed early. The correct answer is to get an upper GI contrast study to evaluate for malrotation and obtain a surgical consultation. Observation (choice C) may result in intestinal ischemia or death. Pyloric stenosis (choice B) presents with nonbilious emesis. Choice D refers to intussusception, which often presents with bloody stools but bilious emesis is unlikely. Necrotizing enterocolitis (choice E) can also present with bloody stools, but usually occurs in premature infants as they approach full enteral feeds.
Which of the following statements is true concerning Meckel's diverticulum?
Answer(s): B
Meckel's diverticuli are usually found incidentally, although they can present with painless lower GI bleeding or inflammation (often confused with acute appendicitis). They are usually found within 2 ft of the ileocecal valve.They represent a remnant of the vitelline (or omphalomesenteric) duct and are found on the antimesenteric side of the ileum. They often contain ectopic gastric mucosa. Acid secretion from this leads to ileal ulceration and bleeding. They can be diagnosed using nuclear medicine scans (technetium pertechnetate) and the treatment is surgical resection.
A55-year-old man with hepatic cirrhosis from alcohol abuse presents with a massive hematemesis. This is his third admission for upper GI hemorrhage in the past 2 months. He is currently receiving appropriate therapy for liver failure, including a beta-blocker and diuretics. He is lethargic and confused. His pulse is 100 and blood pressure is 85/40. His initial hematocrit is 20. After fluid resuscitation, which of the following is the most appropriate management strategy?
Answer(s): D
In patients with liver failure, the source of an upper GI bleed is esophageal varices in 50%, gastritis in 30%, and duodenal ulcers in only about 10%. Esophageal variceal bleeding is a potentially fatal complication of portal hypertension. The initial management should include fluid resuscitation and replacement of blood and clotting factors as needed. The second step is to control the source of bleeding. Medical management may include vasopressin or octreotide. Once the patient is stabilized, endoscopic evaluation of the bleeding is crucial. It can be both diagnostic and therapeutic. Endoscopic techniques for controlling hemorrhage can include sclerotherapy, banding, or balloon tamponade. If these methods are ineffective, or the patient has numerous recurrences, portal shunts can be considered. TIPS have increased in popularity as a method for portal decompression. This can be performed in the acute setting. Surgical shunts are also an option, but are primarily reserved for stable patients with recurrent bleeding episodes and not performed in an acutely unstable patient. Mesocaval shunts connect the SMV to the IVC in a variety of manners. Splenorenal shunts are actually the most common type of shunt. Nonselective shunts that completely divert portal blood flow from the liver can actually increase hepatic encephalopathy. Most surgeons prefer selective shunts, which preserve a component of hepatic blood flow and thus function. Synthetic graft material can be safely used to create the shunts. Postoperative mortality is directly related to the patient's preprocedure medical condition and degree of hepatic failure.
A55-year-old man with hepatic cirrhosis from alcohol abuse presents with a massive hematemesis. This is his third admission for upper GI hemorrhage in the past 2 months. He is currently receiving appropriate therapy for liver failure, including a beta-blocker and diuretics. He is lethargic and confused. His pulse is 100 and blood pressure is 85/40. His initial hematocrit is 20.Endoscopic attempts to control the bleeding are initially successful, but the patient has a recurrent bleed 2 days later. The medicine team obtains a surgical consultation for placement of a shunt.Which of the following statements is true?
Answer(s): C
Which of the following is a contraindication to sentinel lymph node biopsy in breast cancer?
Sentinel lymph node biopsy offers an alternative to full axillary dissection as a diagnostic tool in breast cancer with clinically negative axillary lymph nodes. Patients are injected with technetium-labeled sulfur colloid and isosulfan blue dye. A gamma probe is used along with the visual cues of the blue dye to identify the "sentinel node." The theory is that if this node is negative for malignancy, the rest of the axilla will be negative as well. This spares these patients from an unnecessary axillary lymph node dissection and the morbidity that it entails. Patients with a positive sentinel lymph node require further therapy. Contraindications to the procedure include palpable axillary lymph nodes (because the diagnosis of axillary metastasis is apparent), multicentric disease, and a history of reaction to the blue dye (anaphylaxis and urticaria have been reported). If the lesion is very close to the axilla, there may be too much background radiotracer activity to discern the sentinel node. Lesions under the nipple are quite amenable to this procedure. There are several studies showing that the accuracy and success of this technique is related to surgeon experience. Surgeons are required to perform 2030 procedures with some supervision or confirmation of results before relying completely on sentinel node biopsy
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