MCS & Decker Questions

1. Eight hours after a femoropopliteal bypass with a reversed great saphenous vein, a patient has a cold and pulseless foot. On re-exploration of the groin, a fresh clot is present at the anastomosis of the femoral artery to the saphenous vein graft. 

 

Which of the following is true regarding the coagulation cascade? 

• [A] Tissue factor (TF) plays a key role in activation of the clotting cascade

• [B] Plasminogen is the active form of plasmin

• [C] Fibrinogen converts prothrombin to thrombin

• [D] Plasminogen promotes coagulation by degrading fibrin

• [E] Deficiencies in protein C and protein S result in excessive bleeding

2. If the prevalence of a disease has been more or less constant for the past ten years (i.e., new cases have been balanced by cures or deaths of prevalent cases), what would be the effect of a treatment that prolongs the life of people suffering from the disease? 

• A.   The effect cannot be predicted from the information given.

• B.    It would increase the prevalence.

• C.    It would have no effect on prevalence.

• D.   It would decrease the prevalence.

Seventy-five surgical residents are surveyed to determine whether overnight calls have an impact on their driving habits. The relative risk (RR) of having a traffic accident after calls versus before calls is found to be 2.4 with a 95% CI of 0.4 to 4.8. Which of the following is true? 

• A. The null hypothesis for this study (that there is no difference in accident rates) is a RR of 0.

• Confidence intervals (CIs) are not useful for hypothesis testingB.

•   C. The P-value for this relative risk will probably be greater than 0.05.

• D. A P-value of 0.05 represents a stronger association than does a P-value of 0.007.

• E. This study proves that overnight calls do not increase the risk of having an automobile accident.

A 58-year-old woman undergoing pancreaticoduodenectomy has a 1200cc blood loss after an injury to the superior mesenteric vein. The bleeding is controlled surgically, and a blood transfusion is given intraoperatively. 

 

Which of the following is true regarding the immune effects of blood transfusion? 

 

• [A] Buffy-coat reduction removes more donor leukocytes than leukoreduction

• [B] There is definitive evidence of increased postoperative infections after transfusion

• [C] Leukoreduction can decrease the frequency of febrile transfusion reactions

• [D] Prolonged storage of donated blood does not cause changes in blood components

• [E] Only viral pathogens can be transmitted through blood transfusion

1.     At your hospital, there were 300 new cases of esophageal cancer diagnosed last year.  This statistic for esophageal cancer is the:

• A.   Prevalence

• B.    Median

• C.    Mode

• D.   Incidence

• E.    Mean

A 66-year-old woman with a history of coronary stent placement on both aspirin and Plavix presents with severe abdominal pain, nausea, and vomiting. On CT scan, she is found to have a closed-loop obstruction. She is taken to the operating room for an exploratory laparotomy. 

Which of the following is true regarding platelet inhibition? 

 

• [A] Aspirin is a reversible inhibitor of the cyclooxygenase pathway

• [B] Effects of clopidogrel last for approximately 2-3 days after the last dose

• [C] Platelet transfusion is ineffective for patients on aspirin and Plavix

• [D] Clopidogrel targets the P2Y12 (adenosine diphosphate) receptor

• [E] Most NSAIDs cause irreversible platelet dysfunction

A hospital in Africa is considering adding new oncology services. They think that within the population they serve, more than 30% of people are in favor of these services being offered.

Thus, the hypotheses are as follows:

H₀: ≤ 30% of the population is in favor of oncology services being offered

H_A: > 30% of the population is in favor of oncology services being offered

 

Which of the following represents a Type II error?

• A.   ≤ 30% of the population is in favor of oncology services being offered and the study concludes that > 30% of the population is in favor of oncology services being offered

• B.    ≤ 30% of the population is in favor of oncology services being offered and the study concludes that ≤ 30% of the population is in favor of oncology services being offered

• C.    C.> 30% of the population is in favor of oncology services being offredered and the study concludes that > 30% of the population is in favor of oncology services being offered

• D.   > 30% of the population is in favor of oncology services being offered and the study concludes that ≤ 30% of the population is in favor of oncology services being offered

A 48-year-old man undergoes a complex resection of a dedifferentiated retroperitoneal sarcoma and is admitted to the ICU postoperatively. He subsequently develops hypotension and tachycardia 4 hours postoperatively. 

 

Which of the following laboratory tests should be obtained first?

• [A] Hemoglobin, aPTT, Bleeding Time

• [B] CBC, INR, aPTT

• [C] Fibrinogen, D-dimer, INR

• [D] INR, aPTT, ACT

• [E] aPTT, INR, Factor VIII

1.     To look at the length of hospital stay at your hospital, you review patients who have undergone gastrectomy for cancer. The first seven patients reviewed did well except the last patient, who developed complications. The lengths of stay for these patients were 3, 4, 4, 5, 6, 7, and 41 days. What are the mean, median, and mode of the length-of-stay data?

• A.   Mean = 5, median = 5, mode = 1

• B.    Mean = 10, median = 4, mode = 1

• C.    Mean = 10, median = 5, mode = 41

• D.   Mean = 10, median = 5, mode = 4

• E.    Mean = 5, median = 10, mode = 5

A 77-year-old woman with chronic renal failure is on warfarin for paroxysmal atrial fibrillation. She requires placement of a central venous catheter for temporary dialysis access. Her INR is 2.5. 

 

Which of the following is true regarding warfarin therapy and its reversal? 

• [A] Warfarin acts by decreasing vitamin K absorption in the ileum

• [B] Patients on warfarin typically have an elevated INR and an elevated aPTT

• [C] After administration of vitamin K to reverse the effect of warfarin, warfarin can be resumed at the same dose with immediate restoration of its anticoagulant effect

• [D] Vitamin K quickly reverses the effect of warfarin, whereas the administration of fresh frozen plasma (FFP) takes days to correct the coagulopathy

• [E] Intravenous vitamin K can cause an anaphylactic reaction