Consider the following statements:
a. Light blue blood sample collection tube is used for immunology & serological examination test
b. Red color blood collection tube is used for PT, aPTT, INR examination
c. Light green color blood collection tube is used for chromosome testing and HLA typing examination
d. Grey color blood collection tube is used for glucose and lactate testing
Which of the statements given above is/are correct?

1. A

   c only

2. B

   d only

3. C

   a & b

4. D

   c & d

Appeared in: ISRO 2024

Explanation

• The question asks to identify the correct statement regarding the use of color-coded blood collection tubes.
• Statement 'd' is the only correct one. Grey-top tubes are specifically used for glucose and lactate testing.
• These tubes contain sodium fluoride, an antiglycolytic agent that stops glucose breakdown (glycolysis), and potassium oxalate, an anticoagulant.
• This combination ensures the glucose level in the sample remains stable until analysis, providing an accurate measurement.

Why Other Options Were Wrong

• Option A: This option claims statement 'c' is correct, which is false. Light green tubes contain heparin and are used for plasma chemistry, not chromosome or HLA testing.
• Option C: This option claims statements 'a' and 'b' are correct, both of which are false. Statement 'a' incorrectly assigns immunology to light blue tubes, and statement 'b' incorrectly assigns coagulation studies to red tubes.
• Option D: This option claims statements 'c' and 'd' are correct. While 'd' is correct, 'c' is incorrect, making the combination false.

Related Visual

Clinical Relevance

• Nursing practice connection: Knowing Identification of correct uses for various color-coded blood collection tubes (vacutainers) helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
• Using the correct blood collection tube is a critical pre-analytical step. An incorrect tube can lead to erroneous lab results, potentially causing misdiagnosis, inappropriate treatment, and adverse patient outcomes.
• Nurses must strictly follow the 'Order of Draw' when collecting multiple samples to prevent cross-contamination of additives between tubes. For example, if an EDTA tube (lavender) is filled before a serum tube (red), the excess potassium from EDTA can falsely elevate potassium levels in the serum sample.
• What if? If a nurse draws blood for a glucose test into a red-top tube instead of a grey-top tube, glycolysis will continue in the sample. This will cause a falsely low glucose reading, which could mask hyperglycemia or lead to a missed diagnosis of diabetes mellitus.

How to Approach the Question

• First, carefully read the question to understand that you need to identify the correct statement(s) among the four provided.
• Evaluate each statement (a, b, c, d) individually based on your knowledge of phlebotomy and laboratory test requirements.
• For statement 'a', recall that light blue tubes are for coagulation studies. Therefore, 'a' is false.
• For statement 'b', recall that red tubes are for serum tests, and coagulation studies require a light blue tube. Therefore, 'b' is false.
• For statement 'c', recall that light green (heparin) tubes are for plasma chemistry, while HLA/chromosome tests use yellow (ACD) or lavender (EDTA) tubes. Therefore, 'c' is false.
• For statement 'd', recall that grey tubes contain sodium fluoride to preserve glucose. Therefore, 'd' is true.

Concept Tested & Keywords

• Concept Tested: Identification of correct uses for various color-coded blood collection tubes (vacutainers).
• Stem keywords: blood sample collection tube, light blue, red, light green, grey, immunology, serology, PT
• Lead-in keywords: Which of the statements, is/are correct
• Negative lead-in flag: false

Question ID

QTvHx3EgZ5I5hNEIIOqMcR

Copy ID

Reference Book

E6 Pathology-Vandana Puri & Kavita Gaur Textbook of Pathology and Genetics pp. 379-381, 381-383

E6 Nursing Fundamentals Taylor p. 1119-1121