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Arterial Blood Gas Sampling
\Editor(s):Todd W Thomsen, MD | Gary S Setnik, MD, FACEP
Contributor(s):Murray McLachlan MD
Section Editor(s):David Feller-Kopman, MD
SAMPLE EXCERPT -Pre-Procedure
INDICATIONS




Determination of pH and
partial pressure of
respiratory gases
Determination of other
serum blood levels (e.g.,
lactate)
Assessment of response
to therapeutic
interventions and disease
state
Figure 1 : Arterial blood gas sampling
Sampling of blood in
emergencies when venous
blood cannot be obtained
CONTRAINDICATIONS

Coagulopathy,
anticoagulant
medications, and
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


thrombolysis
Abnormalities of the
overlying skin
Prior vascular surgery at
or proximal to the entry
site
Inadequate local
circulation
EQUIPMENT



Gloves and antiseptic
**UNIVERSAL
PRECAUTIONS**
**STERILE
TECHNIQUE**
Syringe, 25- to 27-gauge
needle and 1% lidocaine
without epinephrine for
anesthetic (optional) See
Local Anesthesia for
further details.
Syringe for aspiration
(heparinized).
Prepackaged ABG kits
are available, or a
standard syringe may be
prepared with heparin.
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

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1.5-inch 22- to 23-gauge
needle and syringe cap
Specimen bag and ice
Bandage
ANATOMY


Radial artery
o The radial artery
is the preferred
Figure 3 : Equipment
site for arterial
puncture.
o Collateral
circulation is from
the palmar
branches of the
ulnar artery. The
artery is medial
and proximal to
the radial styloid
on the volar side
of the wrist.
Brachial artery
o The brachial
artery may be
chosen if the
radial arteries are
not accessible.
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
The brachial
artery lies deep in
the antecubital
fossa and may be
difficult to enter.
It is medial in the
antecubital fossa,
lateral to the
medial
epicondyle, and
medial to the
biceps brachii
tendon.
Femoral artery
o The femoral artery
is the least
desirable site.
o It is located
midway between
the symphysis
pubis and anterior
superior iliac
spine, coursing
under the inguinal
ligament, lateral
to the femoral
vein, and medial
to the femoral
nerve.
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Post-Procedure
CARE



Immediately apply direct
pressure to the puncture
site, for up to 10-15
minutes for patients
taking anticoagulant
medications or who have
coagulopathy.
Check site frequently and
instruct the patient to not
disturb the site and to
Figure 15 : Apply pressure for 5 minutes
report any abnormalities
immediately.
Analyze results.
COMPLICATIONS


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
Hematoma formation
with possible transfusion,
infection, and
compression neuropathy
Distal ischemia
Pseudoaneurysm and
arteriovenous fistula
formation
Localized trauma
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
Infection (soft-tissue and
bone)