Oregon Certified Nursing Assistant State Practice Exam

What time of day is best for collecting a sputum specimen?

1. Late evening

2. Around lunchtime

3. Early morning

4. Right before bedtime

The correct answer is: Early morning

Collecting a sputum specimen is most effective in the early morning for several reasons. During the night, mucus accumulates in the airways while an individual is sleeping, which makes the early morning a prime time for obtaining a sample that reflects what is present in the lungs. The respiratory tract tends to be clear of food and drinks, allowing for a more accurate collection of sputum without contamination. Additionally, the cough reflex is often stronger upon waking, which can facilitate the expulsion of sputum from the lower respiratory tract. In contrast, other times of the day, such as late evening or right before bedtime, are less effective because the mucus may not be as concentrated, and individuals may not be as able to produce an adequate sample. Collecting a specimen around lunchtime could lead to lesser quality as well, since food and other factors throughout the day may interfere with the clarity and integrity of the sample. Thus, the early morning is recognized as the optimal time for collecting sputum specimens for accurate diagnostic purposes.