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How to Collect Specimens from Vesicles or Ulcers

Collecting Vacuum-Assisted Nasopharyngeal Aspirates (NPAs)


                Suction pump,
                Sterile suction catheter (usually size 10, smaller for infants)
                Sterile container (usually 30ml urine jar)

1. Attach catheter to suction pump, leaving wrapper on suction catheter. Turn on suction and adjust to suggested pressure (~100-150 mmHg).

2. Without applying suction, insert catheter into the nose, directed posteriorly and toward the opening of the external ear.

Depth of insertion necessary to reach posterior pharynx is equivalent to distance between anterior naris and external opening of the ear.

Stop when you feel a resistance (you have reached the posterior nasopharynx).

3. Apply suction.

4. Using a rotating movement, slowly withdraw catheter. Catheter should remain in nasopharynx no longer than 10 seconds.

5. Disconnect suction.

6. Put the catheter in a sterile container and label.

7. Do not leave for routine porter transport. Send to virology department immediately.