Arterial puncture for blood gas analysis
Revised: May 12, 2017
Introduction
Arterial blood gas (ABG) analysis evaluates ventilation by measuring blood pH and the partial
pressures of arterial oxygen (PaO2) and carbon dioxide (PaCO2). Blood pH measurement reveals the
blood's acid-base balance, PaO2 indicates the amount of oxygen in the blood, and PaCO2 indicates
the lungs' capacity to eliminate carbon dioxide. ABG samples can also be analyzed for total
hemoglobin, oxygen saturation, saturation of dyshemoglobins, bicarbonate values, and base
excess or deficit.1 Obtaining an arterial blood sample requires percutaneous puncture of the
brachial, radial, or femoral artery or withdrawal of a sample from an arterial line.
Typically, ABG analysis is ordered when respiratory distress or failure is suspected. It's also
performed during episodes of shock and after coronary artery bypass surgery, resuscitation from
cardiac arrest, changes in respiratory therapy or status, and prolonged anesthesia.
Most ABG samples can be drawn by a respiratory therapist or specially trained nurse; however,
collection from the femoral artery is usually performed by a practitioner. The radial artery is the
preferred site because it is small and easy to stabilize.2 3
Equipment
Preheparinized ABG plastic luer-lock syringe specially made for drawing blood for ABG
analysis
20G to 25G 1" to 1½" (2.5 cm to 3.8 cm) needle
Gloves
Antiseptic pad or swab (alcohol, chlorhexidine, or povidone-iodine)2 4 5
Two 2" × 2" (5 cm × 5 cm) gauze pads
Rubber cap for syringe hub
Laboratory biohazard transport bag
Label
Laboratory request form
Small towel
Adhesive bandage
Optional: mask and goggles or mask with face shield, gown, sterile gloves, 1% lidocaine
solution without epinephrine or eutectic mixture of local anesthetics cream, 1-mL syringe
with 22G needle, 1-mL ampule of aqueous heparin (1:1,000), plastic bag, crushed ice,
Doppler ultrasound device, pulse oximeter
Many facilities use a commercial ABG kit that contains some of the equipment listed above.
Preparation of Equipment
If time allows, administer local anesthetic cream at least 1 hour before the procedure because it
requires at least 1 hour to achieve its effect.
This study source was downloaded by 100000850299972 from CourseHero.com on 08-03-2023 00:57:26 GMT -05:00
https://www.coursehero.com/file/30217447/Arterial-Puncture-for-Blood-Gas-Analysis-Lippincott-Procedurespdf/
, Open the ABG kit, and remove the sample label and plastic bag. If the syringe isn't heparinized,
you will have to heparinize it to prevent the sample from clotting. To do so, first attach the 22G
needle to the syringe. Then open the ampule of heparin. Draw all of the heparin into the syringe.
Hold the syringe upright and rotate the barrel while pulling the plunger back to allow the heparin
to coat the entire inside surface of the syringe. Then slowly force the heparin toward the hub of
the syringe, and expel all of the heparin.
ABG analysis should be performed within minutes of obtaining the blood sample.6 Fill a plastic bag
with enough crushed ice to contain the syringe if you expect a delay in analysis.6
Implementation
Verify the practitioner's order.
Review the patient's medical record for current anticoagulation therapy, clotting disorders,
and pertinent laboratory values to determine the risk of prolonged bleeding after the
procedure. Discuss any concerns with the patient's practitioner.
Confirm steady state conditions to ensure accurate test results. If the patient is receiving
oxygen, make sure that this therapy has been underway for 20 to 30 minutes before
collecting an arterial sample. If the patient has received a nebulizer treatment, wait 20
minutes before collecting the sample. If the patient recently underwent suctioning or was
placed on mechanical ventilation or the fraction of inspired oxygen concentration has been
changed, wait at least 15 minutes before collecting a blood sample.4 6
Gather and prepare the necessary equipment.
Perform hand hygiene.7 8 9 10 11 12
Confirm the patient's identity using at least two patient identifiers.13
Provide privacy.14 15 16 17
Explain the procedure to the patient to help ease anxiety and promote cooperation. Tell him
that the needlestick will cause some discomfort but that he must remain still during the
procedure.
Raise the bed to waist level while providing care to prevent caregiver back strain.18
Perform hand hygiene.2 7 8 9 10 11 12
Assess the radial pulse in both wrists to determine the best site from which to draw the
specimen.
Assess circulation to the patient's hand by assessing the radial and ulnar pulses or by
performing the Allen test, pulse oximetry, or a Doppler flow study.19 If the test is negative,
do not use the radial artery; instead, select another site.4 (See Performing the Allen test .)
PERFORMING THE ALLEN TEST
The Allen test is a collateral circulation test performed to assess whether ulnar collateral
blood flow is sufficient to allow for puncture of the radial artery. To perform the Allen test,
position the patient with his wrist extended about 30 degrees. Place a rolled towel under
the wrist to provide support. Instruct the patient to clench his fist. Occlude the radial and
ulnar arteries with your index and middle fingers while the patient's fist remains clenched.
Then ask the patient to slowly unclench his fist. The palm of his hand should be blanched
from lack of arterial blood flow, as shown below.
This study source was downloaded by 100000850299972 from CourseHero.com on 08-03-2023 00:57:26 GMT -05:00
https://www.coursehero.com/file/30217447/Arterial-Puncture-for-Blood-Gas-Analysis-Lippincott-Procedurespdf/
Revised: May 12, 2017
Introduction
Arterial blood gas (ABG) analysis evaluates ventilation by measuring blood pH and the partial
pressures of arterial oxygen (PaO2) and carbon dioxide (PaCO2). Blood pH measurement reveals the
blood's acid-base balance, PaO2 indicates the amount of oxygen in the blood, and PaCO2 indicates
the lungs' capacity to eliminate carbon dioxide. ABG samples can also be analyzed for total
hemoglobin, oxygen saturation, saturation of dyshemoglobins, bicarbonate values, and base
excess or deficit.1 Obtaining an arterial blood sample requires percutaneous puncture of the
brachial, radial, or femoral artery or withdrawal of a sample from an arterial line.
Typically, ABG analysis is ordered when respiratory distress or failure is suspected. It's also
performed during episodes of shock and after coronary artery bypass surgery, resuscitation from
cardiac arrest, changes in respiratory therapy or status, and prolonged anesthesia.
Most ABG samples can be drawn by a respiratory therapist or specially trained nurse; however,
collection from the femoral artery is usually performed by a practitioner. The radial artery is the
preferred site because it is small and easy to stabilize.2 3
Equipment
Preheparinized ABG plastic luer-lock syringe specially made for drawing blood for ABG
analysis
20G to 25G 1" to 1½" (2.5 cm to 3.8 cm) needle
Gloves
Antiseptic pad or swab (alcohol, chlorhexidine, or povidone-iodine)2 4 5
Two 2" × 2" (5 cm × 5 cm) gauze pads
Rubber cap for syringe hub
Laboratory biohazard transport bag
Label
Laboratory request form
Small towel
Adhesive bandage
Optional: mask and goggles or mask with face shield, gown, sterile gloves, 1% lidocaine
solution without epinephrine or eutectic mixture of local anesthetics cream, 1-mL syringe
with 22G needle, 1-mL ampule of aqueous heparin (1:1,000), plastic bag, crushed ice,
Doppler ultrasound device, pulse oximeter
Many facilities use a commercial ABG kit that contains some of the equipment listed above.
Preparation of Equipment
If time allows, administer local anesthetic cream at least 1 hour before the procedure because it
requires at least 1 hour to achieve its effect.
This study source was downloaded by 100000850299972 from CourseHero.com on 08-03-2023 00:57:26 GMT -05:00
https://www.coursehero.com/file/30217447/Arterial-Puncture-for-Blood-Gas-Analysis-Lippincott-Procedurespdf/
, Open the ABG kit, and remove the sample label and plastic bag. If the syringe isn't heparinized,
you will have to heparinize it to prevent the sample from clotting. To do so, first attach the 22G
needle to the syringe. Then open the ampule of heparin. Draw all of the heparin into the syringe.
Hold the syringe upright and rotate the barrel while pulling the plunger back to allow the heparin
to coat the entire inside surface of the syringe. Then slowly force the heparin toward the hub of
the syringe, and expel all of the heparin.
ABG analysis should be performed within minutes of obtaining the blood sample.6 Fill a plastic bag
with enough crushed ice to contain the syringe if you expect a delay in analysis.6
Implementation
Verify the practitioner's order.
Review the patient's medical record for current anticoagulation therapy, clotting disorders,
and pertinent laboratory values to determine the risk of prolonged bleeding after the
procedure. Discuss any concerns with the patient's practitioner.
Confirm steady state conditions to ensure accurate test results. If the patient is receiving
oxygen, make sure that this therapy has been underway for 20 to 30 minutes before
collecting an arterial sample. If the patient has received a nebulizer treatment, wait 20
minutes before collecting the sample. If the patient recently underwent suctioning or was
placed on mechanical ventilation or the fraction of inspired oxygen concentration has been
changed, wait at least 15 minutes before collecting a blood sample.4 6
Gather and prepare the necessary equipment.
Perform hand hygiene.7 8 9 10 11 12
Confirm the patient's identity using at least two patient identifiers.13
Provide privacy.14 15 16 17
Explain the procedure to the patient to help ease anxiety and promote cooperation. Tell him
that the needlestick will cause some discomfort but that he must remain still during the
procedure.
Raise the bed to waist level while providing care to prevent caregiver back strain.18
Perform hand hygiene.2 7 8 9 10 11 12
Assess the radial pulse in both wrists to determine the best site from which to draw the
specimen.
Assess circulation to the patient's hand by assessing the radial and ulnar pulses or by
performing the Allen test, pulse oximetry, or a Doppler flow study.19 If the test is negative,
do not use the radial artery; instead, select another site.4 (See Performing the Allen test .)
PERFORMING THE ALLEN TEST
The Allen test is a collateral circulation test performed to assess whether ulnar collateral
blood flow is sufficient to allow for puncture of the radial artery. To perform the Allen test,
position the patient with his wrist extended about 30 degrees. Place a rolled towel under
the wrist to provide support. Instruct the patient to clench his fist. Occlude the radial and
ulnar arteries with your index and middle fingers while the patient's fist remains clenched.
Then ask the patient to slowly unclench his fist. The palm of his hand should be blanched
from lack of arterial blood flow, as shown below.
This study source was downloaded by 100000850299972 from CourseHero.com on 08-03-2023 00:57:26 GMT -05:00
https://www.coursehero.com/file/30217447/Arterial-Puncture-for-Blood-Gas-Analysis-Lippincott-Procedurespdf/
