Diagnostic Procedures Flashcards

Which of the following is a contraindication for performing venipuncture at a specific site?

Answer: An IV line is running in the same arm

Drawing blood from the same arm as a running IV can dilute the specimen and give falsely abnormal results; an alternate site should be used.

The normal pH range of arterial blood is:

Answer: 7.35–7.45

Normal arterial blood pH is 7.35–7.45; values below 7.35 indicate acidosis and above 7.45 indicate alkalosis.

A Holter monitor is used to:

Answer: Record continuous ECG activity over 24–48 hours

A Holter monitor is a portable ECG device worn for 24–48 hours to detect intermittent arrhythmias not captured during a standard ECG.

Which laboratory finding is characteristic of iron deficiency anemia?

Answer: Decreased ferritin and elevated TIBC

In iron deficiency, ferritin (iron stores) is low and TIBC (total iron-binding capacity) rises as the body tries to capture more iron.

A throat culture collected for suspected streptococcal pharyngitis should be swabbed from the:

Answer: Tonsillar pillars and posterior pharynx

Group A Streptococcus colonizes the tonsillar pillars and posterior pharynx; swabbing this area maximizes sensitivity.

Which glucose tolerance test result confirms gestational diabetes using the 2-hour 75g OGTT?

Answer: 2-hour value ≥153 mg/dL

Per ADA criteria, a 2-hour plasma glucose ≥153 mg/dL on the 75g OGTT is one of the thresholds for diagnosing gestational diabetes.

When a urine specimen cannot be analyzed within 2 hours of collection, it should be:

Answer: Refrigerated at 2–8°C

Refrigeration at 2–8°C preserves urine integrity for up to 24 hours by slowing bacterial growth and chemical decomposition.