Carbon dioxide angiography is an alternative to conventional angiography that uses carbon dioxide as a contrast agent. CO2 displaces blood in vessels, acting as a negative contrast to visualize vessels during X-ray imaging. While it avoids risks of iodinated contrast like nephrotoxicity, CO2 angiography is not suitable for all patients or vessel types due to risks of gas embolism and should be used cautiously in those with pulmonary issues. The procedure involves catheter insertion and injection of medical-grade CO2 gas to outline vessels followed by X-ray imaging and assessment.

1. CARBON DIOXIDE
ANGIOGRAPHY

2. CARBON
DIOXIDE
ANGIOGRAPHY
2
• Carbon dioxide (CO2) angiography is an
alternative to conventional iodinated contrast
angiography.
• Carbon dioxide acts as a contrast agent in this
type of angiography, it displaces the blood in the
vessels and acts as a negative contrast agent.

3. CONTENTS
3
• INTRODUCTION
• PATIENT PREPARATION
• CONTRADICTIONS/
SEDATION
• STANDARD PROCEDURE
• DELIVERY
• IMPORTANT WORDS

4. INTRODUCTION
• Carbon dioxide (CO2) gas was used as a contrast agent in the venous
circulation in the 1950s and 1960s. This imaging developed from
animal and clinical studies, which demonstrated that CO2 use was safe
and well tolerated with peripheral venous injections.
• Because the use of CO2 is not associated with nephrotoxicity or
allergic reactions, it is increasingly being used as a contrast agent for
aortography, as well as for outflow assessment, renal arteriography,
and visceral angiography.
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5. PATIENT PREPARATION
• No specific patient preparation is required for CO2 angiography.
• The standard preparation for catheter angiography is used.
• Patients with a history of allergy to contrast material do not require
steroid preparation.
• CO2 may be used as a contrast agent for outpatient angiography.
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6. CONTRAINDICATIONS
• CO2 should not be used in the thoracic aorta and in arteries above the
diaphragm because of the risk of spinal, coronary, and carotid artery
gas embolism.
• CO2 should be used with caution in patients with pulmonary
insufficiency. because a diagnostic dose of CO2 may cause an
increase in pulmonary arterial pressure.
• CO2 should not be used in patients with an intracardiac septal defect
or a pulmonary arteriovenous malformation because of the possibility
of paradoxical gas embolism.
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7. SEDATION
• Heavy sedation should be avoided during CO2 angiography.
Respiratory depression and hypotension caused by air contamination
may be mistaken for adverse effects of the sedatives and/or analgesics
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8. STANDARD PROCEDURE
1. The patient is positioned on an examination table, usually in a
specialized angiography suite or operating room. The area of
interest, such as the blood vessel being examined, is positioned over
the X-ray equipment.
2. The healthcare team will clean and sterilize the area where the
procedure will take place, typically a specific area of the body where
the blood vessels are located.
3. A local anesthetic is administered to numb the area where a catheter
will be inserted. This helps minimize discomfort during the procedure.
4. A thin, flexible tube called a catheter is inserted into the blood vessel
of interest. The catheter is guided to the specific location within the
blood vessel using X-ray guidance.
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9. 5. Carbon dioxide gas is injected through the catheter into the blood
vessel. CO2 is radiolucent, meaning it does not absorb X-rays, but it
displaces blood and can be visualized on X-ray images.
6. X-ray images or fluoroscopy (real-time X-ray) is used to capture
images of the blood vessels as the CO2 fills and outlines them. The
healthcare team monitors the progress of the procedure on a screen.
7. The images obtained are assessed for any abnormalities or
blockages in the blood vessels. This information can aid in the
diagnosis of vascular conditions or guide interventional treatments.
8. Once the necessary images have been obtained, the catheter is
carefully removed from the blood vessel.
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10. CARBON DIOXIDE DELIVERY
• The CO2 delivery system should be filled
with 99.99% medical-grade CO2 from a
disposable cylinder. The cylinder is
supplied with highly pure gas, a valve, a
regulator, a gas gauge, and a metal
diaphragm with the regulator
• Because of the risk of injection of large
volumes of CO2, the catheter should not
be directly connected to the CO2 cylinder,
which contains a large volume of CO2 at
very high pressure.
• CO2 may be delivered into a vessel by use
of a hand-held syringe, by the plastic bag
system
1 0

11. • In the plastic bag delivery system, the
collection bag is filled with CO2 and is
connected to the reservoir port of the
fluid management system. This system
has airtight connections with the check
valves, the injection port, the bleed-
back port, and the catheter port. The
check valves reduce the need for
stopcock manipulation, which in turn
reduces the risk of air contamination.
• The bag must be tightly connected to
the reservoir port of the delivery
system to prevent air contamination.
• The injection rate depends on the
diameter, length, and flow of the
vessels being imaged.
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12. • When a syringe is used, it should be
filled directly from a CO2 cylinder.
• When the syringe has been filled with
CO2, its pressure should be reduced to
the atmospheric level by quickly
opening and closing the stopcock.
• The syringe method is inconvenient
when multiple injections are necessary.
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13. KEYWORDS
• Intra-arterial contrast agent is a substance used in medical imaging
procedures to enhance the visibility of blood vessels, organs, and
tissues when injected directly into an artery
• Outflow assessment refers to the evaluation and measurement of the
flow of a substance or fluid out of a particular region or organ in the
body.
• Renal arteriography is a medical imaging procedure that involves the
use of contrast material (a contrast agent) and X-ray technology to
visualize the blood vessels (arteries) supplying the kidneys.
• Visceral angiography is a medical imaging technique that involves
the use of a contrast agent and X-ray technology to visualize the blood
vessels supplying the abdominal organs, known as visceral organs.
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14. • Aortography: Aortography is a diagnostic medical imaging procedure
used to visualize and assess the aorta, the body's largest artery.
• Integral Arteriovenous Fistula: An integral arteriovenous fistula is a
surgically created connection between an artery and a vein.
• Intracardial Septal Defect (Intracardiac Septal Defect): An
intracardial septal defect, often referred to simply as a septal defect, is
a congenital heart condition where there is an abnormal opening or
hole in the septum (the dividing wall) between the chambers of the
heart.
• Catheter Angiography: Catheter angiography, also known as
angiogram or arteriogram, is a medical procedure that involves the use
of a catheter (a thin, flexible tube) to inject a contrast agent into blood
vessels.
• Contrast Agent: A contrast agent, also known as a contrast medium
or contrast dye, is a substance used in medical imaging procedures to
enhance the visibility of internal structures or organs within the body.
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15. SUMMARY
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CO2 angiography is generally considered safe
and has advantages in certain clinical
situations. However, it may not be suitable for
all patients or all types of vascular imaging. The
choice of contrast agent and imaging technique
depends on the specific clinical scenario and
the judgment of the medical team.

16. THANK YOU
ALFINA SURTI