arterial puncture Flashcards
what is the primary purpose of arterial puncture
To obtain blood for arterial blood gas (ABG) tests
- It will provide respiratory function of the blood pH and adequate oxygenation level in the body.
Disadvantages of arterial puncture
Technically difficult
Potentially more painful and hazardous than venipuncture
Thus, not normally used for routine blood test
arterial blood
- Best specimen for evaluating respiratory function
- Has high oxygen content & consistency of composition
- Used in diagnosis & management of respiratory disorders
- Provide valuable info abt patient’s:
Oxygenation
Ventilation
Acid-base balance - Used in management of electrolyte and acid base balance in patient with diabetes and other metabolic disorders
- Specimens are sensitive to effects of preanalytical error
Purpose of ABG Analysis
Indicated how well the lungs and kidneys are interacting to maintain normal blood pH (acid-base balance)
how the lungs and kidneys work together to maintain the body’s acid-base balance
that is important for keeping your blood at the right pH level
Lungs: Control carbon dioxide (CO₂) levels. CO₂ combines with water (H₂O) in the body to form carbonic acid (H₂CO₃), which then splits into hydrogen ions (H⁺) and bicarbonate (HCO₃⁻). Breathing out more CO₂ helps decrease acidity in the blood, while keeping CO₂ increases acidity.
Kidneys: Regulate bicarbonate (HCO₃⁻) levels. Bicarbonate is like a “buffer” that helps neutralize acid. The kidneys can add or remove bicarbonate from the blood as needed to maintain balance.
In summary, lungs manage CO₂, and kidneys manage bicarbonate (HCO₃⁻) to keep your blood at a healthy pH.
what are the commonly measured ABG analytes
index card
Personnel who Perform Arterial Puncture
Nurses
Phlebotomists (level II)
Medical Technologist
- However, it is not part of our duty, only the testing.
Respiratory Therapists (most of the time)
Emergency Medical Technicians
Site Selection Criteria
- Presence of collateral circulation
- Blood supply from more than one artery (Modified Allen Test) - Artery accessibility & size
- The location, if high risk of injury.
- Making sure that the artery is stable as it might roll.
3.Type of tissue surrounding puncture site
- Low risk of injuring adjacent structures or tissue during puncture
- Ability to fix or secure artery to prevent rolling
- Adequate pressure can be applied to artery after collection - Absence of inflammation, irritation, edema, hematoma, lesion, wound, AV shunt in close proximity or recent arterial puncture.
what are the 3 Arterial Puncture Sites
The Radial Artery
The Brachial Artery
The Femoral Artery
Located in the lateral side in the anatomical position.
the radial artery
- At the thumb position.
- You can feel the pulse under the thumb.
radial artery advantages and disadvantages
Advantages:
Good collateral circulation (radial & ulnar arteries)
Ulnar artery can provide blood to your hand.
Easy to palpate (close to surface of skin)
Less chance of hematoma formation after collection, no major nerves/ vein near your radial artery.
Disadvantages:
Requires considerable skill to puncture it successfully due to small size.
Difficult to locate patients with hypovolemia or low cardiac output.
brachial artery advantages and disadvantages
Advantage:
- Large & relatively easy to palpate & puncture
- Sometimes the preferred artery for large volume of blood
- Adequate collateral circulation (but not as good as radial)
Disadvantages:
- Deeper & can be harder to palpate than radial artery
- Lies close to basilic vein; risk of mistakenly puncturing it
- Lies close to median nerve; risk of pain & nerve damage
- Increased risk of hematoma formation
Largest artery used for arterial puncture
The Femoral Artery
- Located superficially in groin, lateral to pubis bone
who performs the femoral artery
Performed primarily by physicians & specially trained emergency room personnel
*Generally used only in emergency situations or when no other sites is available
advantages and disadvantages of femoral artery
Advantages:
- Large & easily palpated & punctured
- Sometimes, only site where arterial sampling is possible
- Especially for patient who is hypoglycemic
Disadvantages:
- Poor collateral circulation
- Lies close to femoral vein; risk of mistakenly puncturing it
- Increased risk of infection due to location & pubic hair
- Risk of dislodging plaque buildup from inner artery walls
- Requires extended monitoring for hematoma formation
what are the other sites for arterial puncture
in infants:
scalp
umbilical arteries
in adults:
dorsalis pedis arteries
what are the equipment and supplies needed for the arterial puncture
Equipment:
Personal protective equipment
Fluid-resistant lab coat, gown or apron
Gloves
Face protection
*No need to use a tourniquet. Just need to pulse.
Supplies:
Antiseptic
Local anesthetic (optional)
Sharp, short-bevel hypodermic needle
1 to 5 ml self-filling syringe
Luer-tip normal or bubble removal cap (to cover the hub of the syringe barrel to prevent air from entering the syringe)
Coolant (ice bath)
2 by 2 gauze bandage
ID & labeling materials
Puncture-resistant sharps container
patient preparation
Identification and explanation of procedures
Patient preparation and assessment
Steady state
Modified allen test
Local anesthetic administration
Modified Allen Test
- Have patient make a tight fist
- Compress patient’s radial & ulnar arteries at the same time
- Maintaining pressure, have patient open hand slowly
- Lower patient’s hand & release pressure on ulnar artery only
- Assess results:
Positive - hand flushes pink
Negative - hand does not flush pink - Record results on requisition
Local Anesthetic Administration
- Verify absence of allergy to anesthetic or its derivatives
- Sanitize hands & don gloves
- Attach needle to syringe
- Clean stopper of anesthetic bottle with alcohol wipe
- Insert needle through bottle stopper & withdraw anesthetic
- Carefully replace needle cap & put syringe in horizontal position
- Clean and air dry site
- Insert needle into skin at site at angle of 10 degrees
- Pull back slightly on plunger
- Slowly expel contents into skin, forming a raised wheal
- Wait 1 to 2 min. before proceeding w arterial puncture
- Note anesthetic application on requisition
Radial ABG Procedure
transes
[after sanitizing hands and donning of gloves,
assess collateral circulation
after locating artery, administer local anesthetic (making sure to aspirate to ensure you are not
within a blood vessel prior to administration)
30-45 degree angle, slowly direct it toward pulse & stop when a flash of blood appears
Allow syringe to fill to proper level
○ Do not aspirate.(pull back) ]
Modified Allen’s Test
Elevate the hand and make fist
Press ulnar and radial arteries
Open the hand (blanched)
Release ulnar artery and look for perfusion
Usually < 6 seconds in negative test
Hazards and Complications of Arterial Puncture and Sampling Errors
Hazard and Complications:
- Arteriospasm
- Artery damage
- Discomfort
- Hematoma
- Infection
- Numbness
- Thrombus formation
- Vasovagal response
Sampling errors:
- Air bubbles delay in analysis
- Improper mixing
- Improper syringe
- Obtaining venous blood by mistake
- Use of anticoagulant
- Use of too much or too little heparin
Reasons to rejecting ABG sample
Air bubbles
Clotted/ Hemolyzed specimen
improper/ Absent ID
Improper transportation temperature
Inadequate volume
Prolonged delay in delivery of sample
Wrong type of syringe used
