Nasopharyngeal and Oropharyngeal Swabs – OSCE Guide

This guide provides an overview of performing a nasopharyngeal and oropharyngeal swab for the purposes of viral sample collection (e.g. COVID-19). It does not include details on the appropriate personal protective equipment (PPE) required, which is pathogen dependent (see our guide to PPE here).

It should be noted that this guide only provides a general approach to sample collection and the details regarding storage medium and transport vary depending on the pathogen being tested for. You should always consult your local guidelines before taking a sample from a patient.


Introduction

  • Wash your hands
  • Introduce yourself
  • Confirm the patient’s details (e.g. name and date of birth)
  • Explain the procedure (including the fact that the procedure will be uncomfortable and will likely elicit a gag reflex)
  • Gain consent

Gather Equipment

  • Gloves
  • Additional appropriate PPE
  • Flexible, plastic nasopharyngeal or oropharyngeal swab
  • Tongue depressor (if taking an oropharyngeal sample)
  • Specimen tube containing universal transport medium

Nasopharyngeal and oropharyngeal swab tips for the purposes of viral sample collection must be synthetic. Cotton or calcium alginate tipped swabs can kill viral particles and/or interfere with PCR testing.

Only swabs with flexible plastic shafts should be used, wooden shafts increase the risk of patient injury during the procedure.


Nasopharyngeal Swab

1. With the patient seated, ask them to first blow their nose and then you should check for any obstruction of the nasal passages.

2. Carefully open the swab packaging, only handling the swab above the breakpoint.

3. Measure the distance from the corner of the nose to the front of the ear and insert the shaft ONLY half this length. In adults, this distance is usually about 4 cm.

4. Tilt the patient’s head back 70-degrees to straighten the passage between the nose and the nasopharynx.

5. Avoiding contact with external nasal skin, insert the swab along the medial part of the septum, along the base of the nose (gently rotating the swab may be helpful to aid insertion). If resistance is encountered on one side, try the alternative nostril as the patient may have a deviated nasal septum.

6. Once the swab is fully inserted, leave it in place for several seconds to absorb nasopharyngeal secretions.

7. Slowly remove the nasopharyngeal swab whilst rotating it.

8. Insert the nasopharyngeal swab into a tube of universal transport medium, ensuring that the swab tip is fully submerged into the liquid of the tube.

9. Snap off the shaft of the nasopharyngeal swab at the break line, allowing the remaining shaft and swab tip to remain submerged in the tube’s liquid.

10. Clearly label the sample with the patient’s name, date of birth and unique identification number.

11. Appropriately package the specimen for transport to the lab.

12. Arrange for transport of the specimen within an appropriate timeframe.

 

Nasopharyngeal swab
Nasopharyngeal swab

Oropharyngeal Swab

1. With the patient seated, ask them to open their mouth wide, stick their tongue out and say “ahhh”.

2. Depress the patient’s tongue using a tongue depressor.

3. Insert the oropharyngeal swab, avoiding touching the teeth, tongue and other structures.

4. Collect the sample from the oropharyngeal wall, twisting the swab slowly and thoroughly to increase the likelihood of collecting an adequate sample.

5. Remove the oropharyngeal swab.

6. Insert the oropharyngeal swab into the tube of universal transport medium, ensuring that the swab tip is fully submerged into the liquid of the tube.

7. Snap off the shaft of the oropharyngeal swab at the break line, allowing the remaining shaft and swab tip to remain submerged in the tube’s liquid.

8. Clearly label the sample with the patient’s name, date of birth and unique identification number.

9. Appropriately package the specimen for transport to the lab.

10. Arrange for transport of the specimen within an appropriate timeframe.

Oropharyngeal Swab
Oropharyngeal swab

To complete the procedure…

  • Wash your hands
  • Thank the patient
  • Check if the patient has any questions
  • Offer the patient some tissues if appropriate (to clean nasal/oral secretions)
  • Document the procedure in the patient’s medical notes

 

  1. Centers for Disease Control (CDC) and Prevention. Influenza Specimen Collection. Available from: [LINK]
  2. World Health Organisation. WHO guidelines for the collection of human specimens for laboratory diagnosis of avian influenza infection. Published 12th January 2005. Available from: [LINK]

 

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Nasopharyngeal and Oropharyngeal Swabs – OSCE Guide