Pre‐procedure

ActionRationale

1. 1.Show
   Introduce yourself to the patient, and explain and discuss the procedure with them. Obtain consent to proceed in all cases except in emergencies when the patient is unable to consent.
   To ensure that the patient feels at ease, understands the procedure and gives their valid consent (NMC [165], C).
2. 2.Show
   Wash hands with bactericidal soap and water or an alcohol‐based handrub.
   To minimize the risk of cross‐infection (NHS England and NHSI [155], C).
3. 3.Show
   Prepare trolley.
   To minimize the risk of cross‐infection (DH [46], C).
4. 4.Show
   Apply gloves and apron.
   To prevent contamination of hands with blood (NHS England and NHSI [155], C).
5. 5.Show
   Check the three‐way tap is closed to port (Action figure 13.13).
   To prevent backflow of blood and blood spillage. E
6. 6.Show
   If safe to do so, press the silence button on the arterial monitor for duration of sampling.
   The continual alarm disturbs both the patient and others in the unit. Alarms of no clinical significance should be minimized. E

Procedure

1. 7.Show
   Remove the cap from the three‐way tap and clean the port with a swab soaked in 2% chlorhexidine in 70% alcohol for 15 seconds and allow to dry.
   To minimize the risk of infection (NHS England and NHSI [155], C).
2. 8.Show
   Attach a 5 mL Luer‐Lok syringe.
   To remove saline, old blood and small emboli from the dead space within the cannula (Danckers and Fried [41], E).
3. 9.Show
   Turn the three‐way tap to the artery and port (Action figure 13.14).
   To prevent contamination of blood with flush solution. E
4. 10.Show
   Slowly withdraw 3–5 mL of blood.
   To prevent the artery going into spasm and to withdraw the saline from the line to ensure the sample is fresh blood. E
5. 11.Show
   Turn the three‐way tap diagonally to close off both the artery and the flush (Action figure 13.15).
   To enable the syringe to be removed without blood loss and to prevent saline from contaminating the sample. E
6. 12.Show
   Remove the 5 mL syringe and discard.
   To discard the contaminated sample. E
7. 13.Show
   Connect the blood gas syringe to the three‐port.
   In order to withdraw the sample. E
8. 14.Show
   Turn the three‐way tap to the artery and port (Action figure 13.14).
   To withdraw arterial blood. E
9. 15.Show
   Slowly remove the recommended amount of blood (0.6–1 mL).
   To prevent the artery going into spasm, ensuring the correct volume of blood mixes with the heparin in the gas syringe (Chernecky and Berger [32], E; Lipsitz [127], R).
10. 16.Show
    Turn the three‐way tap diagonally to close off both the artery and the flush (Action figure 13.15).
    To prevent haemorrhage or blood spillage. E
11. 17.Show
    Remove the gas syringe, gently rotating as you do so.
    To ensure the blood and heparin contained within the syringe are mixed. E

Post‐procedure

1. 18.Show
   Turn the three‐way tap to the ‘open to port’ position; to flush the port, apply a sterile swab to the port and flush by squeezing the actuator (see manufacturer's instructions) (Action figure 13.16).
   The swab will absorb the blood, preventing contamination. E

   Blood is cleared from the port, reducing the risk of thrombosis and microemboli. E
2. 19.Show
   Turn the three‐way tap to the ‘open to artery’ position and flush the cannula towards the artery by gently squeezing the actuator. As the cannula is flushed, observe the patient's digits for signs of blanching or discolouration, and listen for complaints of pain from the patient.
   Blood is cleared from the cannula and arterial tubing. E

   To ensure ear_ly recognition of proximal or distal embolism. E
3. 20.Show
   Clean the port with chlorhexidine in 70% alcohol swab and allow to dry.
   To minimize the risk of infection (DH [46], C).
4. 21.Show
   Apply a new sterile Luer‐Lok cap and check it is secure.
   To minimize the risk of infection and prevent exsanguination. E
5. 22.Show
   Remove gloves and wash hands.
   To minimize the risk of infection (NHS England and NHSI [155], C).
6. 23.Show
   Check the pressure infuser cuff is inflated to 300 mmHg.
   To prevent backflow of blood into the circuit. E
7. 24.Show
   Analyse the sample or send it to the nearest blood gas analyser. Document the result and report abnormalities.
   To obtain a result. E

   To ensure timely and accurate record keeping (NMC [165], C; WHO [260], C).