Quality Assurance Procedures

There are a number of quality assurance procedures which play an important role in obtaining accurate, reliable blood gas results for your patient. It is also an essential part of infection control. Let’s check out some of the considerations that are important for quality assurance.

All staff carrying out blood sampling procedures should have an understanding of blood vessel anatomy and physiology, as well as an awareness of the blood exposure and infection control risks of the procedure.

When taking an ELCBG, you should work in a quiet, clean, well-lit area. The patient should be seated in a chair with arms, and the space around the chair should be clear just in case the patient experiences an episode of syncope.

Test protocols, or Standard operating procedures (SOPs) are required for earlobe capillary blood gas measurements. These protocols should be available to every individual performing ELCBG tests on patients.

As with all diagnostic tests performed on our patients, we should always check we have the correct sat in front of us before starting the test, and we have a system for inputting the patient’s details into the device with little room for human error (using a barcode, for example).

For syringe samples, once the sample has been obtained expel any air bubbles and the first drop of blood into a tissue before capping the syringe. This helps stabilise the sample by minimising air contamination. It is important to mix the sample thoroughly. The best way to do this with a syringe is to roll the sample between both hands, gently inverting the syringe at the same time.

For capillary samples, once the sample has been obtained use a magnet to move the metal flea up and down the tube numerous times to aid thorough mixing. Continue to do this until the sample is analysed.

Samples are stable for approximately 20 minutes post collection as the blood continues to metabolise. Keep this mind if the sample requires transportation to another ward or laboratory. If there is a delay between sample collection and sample analysis, measures to prevent a blood clot by rolling the sample and inverting the syringe or capillary tube.

For the patient’s records, details of the procedure including informed consent, sample site and number of attempts made should be provided. Every blood gas result should include the following measurements:

  • pH
  • PaCO2
  • PaO2
  • HCO3
  • Base Excess
  • SaO2
  • SpO2 (measured using a pulse oximeter at the same time as the blood gas measurement)
  • FiO2

Each ELCBG service should have a method for reporting adverse events.

Mark as Understood

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