Question

A 60-year-old lady underwent abdominal surgery and on the 4th post-operative day was diagnosed to have Systemic Inflammatory Response Syndrome (SIRS). What are the features of SIRS?
1. Normal body temperature and normal respiratory rate
2. WBC count > 12 × 10⁹/L or < 4 × 10⁹/L
3. Respiratory rate > 20 breaths/minute and heart rate > 90 beats/minute
4. Respiratory rate < 10 breaths/minute
Select the correct answer using the codes given below:

• A. 1 and 4
• B. 1 and 2
• C. 2 and 3
• D. 2 and 4

Hint:

Recall the four SIRS parameters and remember that all of them describe an abnormal, not a normal, value.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
The question is testing the standard diagnostic criteria for Systemic Inflammatory Response Syndrome (SIRS) in a post-operative patient, and asks which of the four listed statements actually match those criteria.

Step 2: Key Concept or Approach:
SIRS is diagnosed when at least two of the following are present: temperature above 38°C or below 36°C, heart rate above 90 beats/minute, respiratory rate above 20 breaths/minute (or PaCO2 below 32 mmHg), and white cell count above 12 × 10⁹/L, below 4 × 10⁹/L, or more than 10% immature (band) forms. Every criterion reflects an abnormal, not a normal, parameter.

Step 3: Working Through the Options:
Statement 1 describes a normal temperature and normal respiratory rate, which is the opposite of what SIRS requires, so it is wrong. Statement 2 (WBC above 12 × 10⁹/L or below 4 × 10⁹/L) matches the white cell criterion exactly, so it is correct. Statement 3 (respiratory rate above 20 and heart rate above 90) matches both the respiratory and cardiac criteria, so it is correct. Statement 4 describes a very low respiratory rate, which is not part of the SIRS definition — SIRS looks for tachypnea, not bradypnea — so it is wrong. Putting the correct statements together gives 2 and 3.

Step 4: Conclusion:
The correct answer is 2 and 3.