Author Question: A 53-year-old woman arrives at the hospital with bleeding into the back of the throat and has a ... (Read 131 times)

fasfsadfdsfa · **on:** Jun 25, 2018

A 53-year-old woman arrives at the hospital with bleeding into the back of the throat and has a coagulation screen performed.

She has no history of abnormal bleeding before this despite major stress to hemostasis in the past: she was in a major automobile accident at age 37 and has had impacted wisdom teeth extracted. Her coagulation results follow:

Patient's Results Reference Range 1:1 Mix with Normal Plasma
Prothrombin time (PT) 13.1 seconds 11-15 seconds
Partial thromboplastin time (PTT) 87 seconds 25-37 seconds 35
Fibrinogen 380 mg/dL 200-400 mg/dL

Which of the following is the most likely cause for her bleeding?

a. Factor XII deficiency
b. Factor IX deficiency
c. Factor VIII deficiency
d. Factor VIII inhibitor

Question 2

Which of the following specimens would be acceptable for platelet aggregation studies?

a. Blood drawn in ethylenediaminetetr aacetic acid (EDTA) and kept at room temperature for 6 hours
b. Blood drawn in 3.2 sodium citrate and transported to the laboratory on ice (2 to 4 C)
c. Blood drawn in a serum separator tube
d. Blood drawn in 3.2 sodium citrate and kept at room temperature for 2 hours after drawing

robbielu01 · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

ANS: D
This patient is bleeding abnormally. However, she has had major trauma in the past with no abnormal bleeding; this suggests the problem is acquired, not congenital. The PTT is prolonged, so the common pathway appears to be intact. The prolonged PTT fully corrects on a 1:1 mix, although at the upper end of the reference range. Putting all of this together, the most likely problem is an acquired factor VIII inhibitor.

Answer to Question 2

ANS: D
Platelet function studies must be performed within 3 hours of drawing, and the specimen must be kept at room temperature because chilling damages platelets. The blood sample must be drawn in 3.2 sodium citrate.