CompTIA
Checkpoint
ISC
HP
Dell
EC-Council
EXIN
Fortinet
ITIL®
Juniper
PMI
Microsoft
VMware
Avaya
Google
Salesforce
Amazon
Palo Alto Networks
Certiport
ISC2
All Vendors
  2. Home
  3. Exams
  4. USMLE
  5. STEP3

Free STEP3 Exam Braindumps (page: 57)

Page 56 of 202
PDF with 804 Questions

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?

  1. An upper GI contrast study should be obtained immediately.
  2. The most likely explanation is pyloric stenosis.
  3. The patient should be admitted for IV fluid resuscitation and observation. If she does not improve over the next 24 hours, a surgical consultation should be obtained.
  4. An air contrast enema is the most appropriate next step.
  5. A nasogastric tube should be inserted and IV antibiotics started to treat probable necrotizing enterocolitis.

Answer(s): A

Explanation:

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?

  1. It is found within 2 in. of the ileocecal valve.
  2. It represents a remnant of the embryonic vitelline duct.
  3. Ectopic colonic epithelium is found in it.
  4. Diagnosis is best made by CT scan.
  5. The diverticulum is usually found on the mesenteric border of the bowel.

Answer(s): B

Explanation:

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?

  1. The transplant team should be called immediately.
  2. The bleeding is probably secondary to an uncontrolled duodenal ulcer related to his alcohol use.
  3. Red blood cells should be administered immediately, but fresh frozen plasma should be withheld if possible.
  4. Endoscopic control options include sclerotherapy and banding.
  5. Transjugular intrahepatic portal systemic shunt (TIPS) is not an option in the immediate period.

Answer(s): D

Explanation:

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?

  1. The best shunts are nonselective, meaning that they divert all blood from the portal system.
  2. Synthetic graft materials should never be used because of the risk of infection.
  3. A mesocaval shunt involves connecting the superior mesenteric vein (SMV) to the inferior vena cava (IVC).
  4. Encephalopathy rarely worsens after the placement of the shunt. In fact, it often improves in these patients.
  5. Postoperative mortality for emergency shunts is related more to the type of shunt placed rather than the degree of hepatic failure in the patient.

Answer(s): C

Explanation:

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.






Post your Comments and Discuss USMLE STEP3 exam with other Community members:

STEP3 Discussions & Posts