Arterial Blood Gas Arterial Blood Gas Procedure (ABG)Procedure (ABG)

By: Reymond E. Bicariato, RNBy: Reymond E. Bicariato, RN

Objectives:Objectives:

By the end of this session students will:By the end of this session students will:

1.1. Understand ABG and its terms? Understand ABG and its terms?

2. Know some of the indications and 2. Know some of the indications and contraindications for performing an contraindications for performing an arterial puncture.arterial puncture.

3. Be able to demonstrate the technique 3. Be able to demonstrate the technique for performing an arterial puncture.for performing an arterial puncture.

What is an ABGWhat is an ABG

Arterial Blood GasArterial Blood Gas Drawn from artery- radial, brachial, femoralDrawn from artery- radial, brachial, femoral It is an It is an invasiveinvasive procedure. procedure. Caution must be taken with patient on Caution must be taken with patient on

anticoagulants.anticoagulants. Helps differentiate oxygen deficiencies from Helps differentiate oxygen deficiencies from

primary ventilatory deficiencies from primary primary ventilatory deficiencies from primary metabolic acid-baseabnormalities. metabolic acid-baseabnormalities.

Common terms:Common terms:

PCO2 PCO2 Partial pressure CO2 Partial pressure CO2 PO2PO2 Partial pressure O2 Partial pressure O2 HCO3HCO3 Bicarbonate Bicarbonate BEBE Base excess Base excess SaO2SaO2 Oxygen Saturation Oxygen Saturation

Normal ABG valuesNormal ABG values

pHpH 7.35 – 7.45 7.35 – 7.45 PCO2PCO2 35 – 45 mmHg35 – 45 mmHg PO2PO2 80 – 100 mmHg80 – 100 mmHg HCO3HCO3 22 – 26 mmol/L22 – 26 mmol/L BEBE -2 - +2 -2 - +2 SaO2SaO2 >95%>95%

Information Obtained from an ABG:Information Obtained from an ABG:

Acid base statusAcid base status OxygenationOxygenation

Dissolved O2 (pO2)Dissolved O2 (pO2) Saturation of hemoglobinSaturation of hemoglobin

CO2 eliminationCO2 elimination Levels of carboxyhemoglobin and Levels of carboxyhemoglobin and

methemoglobin methemoglobin

Indications:Indications:

Assess the ventilatory status, oxygenation and Assess the ventilatory status, oxygenation and acid base status.acid base status.

Assess the response to an intervention.Assess the response to an intervention.

Contraindications:Contraindications:

Bleeding diathesisBleeding diathesis AV fistulaAV fistula Severe peripheral vascular disease, absence of an Severe peripheral vascular disease, absence of an

arterial pulsearterial pulse Infection over site Infection over site

Complications:Complications:

The most common complication from an The most common complication from an arterial puncture isarterial puncture is hematomahematoma at the site. at the site. Less Less common but important complications are common but important complications are thrombus in the artery andthrombus in the artery and infection at the infection at the site.site.

Allen test for collateral flow:Allen test for collateral flow:

Which Artery to Choose?Which Artery to Choose?

The The radial arteryradial artery is superficial, has collaterals is superficial, has collaterals and is easily compressed. It should almost and is easily compressed. It should almost always be the first choice.always be the first choice.

Other arteries (femoral, dorsalis pedis, Other arteries (femoral, dorsalis pedis, brachial) can be used in emergencies.brachial) can be used in emergencies.

Preparing to perform the Procedure:Preparing to perform the Procedure:

Make sure you and the patient are comfortable.Make sure you and the patient are comfortable. Assess the patency of the radial and ulnar Assess the patency of the radial and ulnar

arteriesarteries

Equipment:Equipment:

Prior to performing an arterial puncture all the Prior to performing an arterial puncture all the necessary equipment should be ready at the bedside. necessary equipment should be ready at the bedside. Equipment includes:Equipment includes:

GlovesGloves Heparinized arterial blood gas syringe kitHeparinized arterial blood gas syringe kit Alcohol swabsAlcohol swabs 2x2 gauze2x2 gauze TapeTape Patient label (put on syringe prior to putting in ice Patient label (put on syringe prior to putting in ice

bag)bag) Bag of ice for transport to labBag of ice for transport to lab

Heparinized arterial blood gas Heparinized arterial blood gas syringe kitsyringe kit

Performing the Procedure:Performing the Procedure: Put on glovesPut on gloves Prepare the sitePrepare the site

Drape the bedDrape the bed Cleanse the radial area with a alcoholCleanse the radial area with a alcohol

Position the wrist (hyper-extended, using a rolled up Position the wrist (hyper-extended, using a rolled up towel if necessary)towel if necessary)

Palpate the arterial pulse and visualize the course of Palpate the arterial pulse and visualize the course of the artery.the artery.

If you are going to use local anesthetic, infiltrate the If you are going to use local anesthetic, infiltrate the skin with 2% xylocaine.skin with 2% xylocaine.

Open the ABG kitOpen the ABG kit

Performing the Procedure (cont.)Performing the Procedure (cont.) Line the needle up with the artery, bevel side Line the needle up with the artery, bevel side

up.up. Enter the artery and allow the syringe to fill Enter the artery and allow the syringe to fill

spontaneously.spontaneously. Withdraw the needle and hold pressure on the Withdraw the needle and hold pressure on the

site.site. Protect needleProtect needle Remove any air bubblesRemove any air bubbles Gently mix the specimen by rolling it between Gently mix the specimen by rolling it between

your palmsyour palms Place the specimen on ice and transport to lab Place the specimen on ice and transport to lab

immediately.immediately.

Note:Note: The radial artery at the wrist is very The radial artery at the wrist is very

superficial and in fact this is one of the superficial and in fact this is one of the reasons it is so frequently used for arterial reasons it is so frequently used for arterial blood gas sampling. One of the most blood gas sampling. One of the most common reasons for missing a puncture is common reasons for missing a puncture is that the nurse misses the artery on the way that the nurse misses the artery on the way through. This is often followed by attempts through. This is often followed by attempts to find the artery even deeper by "poking to find the artery even deeper by "poking around". This will be unsuccessful and around". This will be unsuccessful and much to the displeasure of the patient. If much to the displeasure of the patient. If you don't encounter the artery in the you don't encounter the artery in the superficial subcutaneous tissue you should superficial subcutaneous tissue you should pull the needle back and try again. pull the needle back and try again.

The EndThe End

THANK YOU THANK YOU VERY MUCH!!!!! VERY MUCH!!!!!