FAQ

Yes, CO₂ angiography is particularly well-suited for patients with kidney failure or those on dialysis, precisely because it does not further damage kidney function. It is often the preferred choice in these cases.

Absolutely. CO₂ is a completely different type of contrast agent and does not cause allergic reactions. If you've had allergic reactions to iodinated contrast in the past, CO₂ angiography is an excellent alternative for you.

CO₂ dissolves very quickly in the blood and is eliminated within seconds through normal breathing. There is no accumulation in the body, which is why the procedure can be repeated more frequently than with iodinated contrast.

Yes, CO₂ can be used not only for diagnostic purposes but also during therapeutic procedures such as angioplasty, stent placement, or treatment of arteriovenous fistulas, offering the same safety advantages even during more complex interventions.

With modern technologies like Angiodroid, CO₂ image quality is excellent and comparable to that obtained with iodinated contrast. In some specific cases, it may be necessary to supplement with a small amount of iodine, but this is evaluated on a case-by-case basis.

No, CO₂ has been used in vascular imaging since 1914 and has been refined over the decades. It is a well-established and proven technique that has become increasingly popular with advancing technology.

Contrast-induced nephropathy, abbreviated as CIN, is acute damage to kidney function that can occur following the administration of iodinated contrast media.

It typically manifests as an increase in blood creatinine levels within 48-72 hours of the procedure.

CIN is more common in patients who already have compromised kidney function, diabetes, dehydration, or advanced age. In most cases it is reversible, but in more severe situations it can lead to permanent deterioration of kidney function or require temporary or permanent dialysis. Currently, it is the third most common cause of kidney damage during hospital stays.

With CO₂ angiography, the risk of CIN is completely eliminated because the gas does not pass through the kidneys and has no toxic effect on kidney tissue.

Creatinine is a waste product naturally produced by muscle metabolism. It is filtered by the kidneys and eliminated through urine. Blood creatinine levels are therefore a key indicator of kidney function.

Elevated levels (above 1.5 mg/dl) indicate that the kidneys are not filtering adequately and that kidney function is reduced.

Before undergoing angiography with iodinated contrast, it is essential to check creatinine levels because elevated values significantly increase the risk of contrast-induced nephropathy.
With CO₂, even patients with very high creatinine can safely undergo the exam.

eGFR (estimated Glomerular Filtration Rate) is a parameter that indicates how effectively the kidneys filter blood.

An eGFR below 60 ml/min/1.73 m² indicates reduced kidney function and increases the risk of complications in case of iodinated contrast administration.
For these patients, CO₂ represents the only truly safe contrast alternative.

Biocompatibility means that a substance is naturally compatible with living tissues and does not cause adverse reactions in the body.
CO₂ is particularly biocompatible because:

• It is naturally present in the body: our body continuously produces CO₂ as a product of cellular metabolism
• It is managed by physiological systems: we have natural mechanisms to regulate CO₂ levels (primarily through respiration)
• It is non-toxic: unlike iodine, CO₂ has no toxic effects on the kidneys, liver, or other organs
• It is eliminated rapidly: through the lungs within seconds
• It does not cause immune reactions: the immune system recognizes it as an endogenous substance

The anatomical limit for CO₂ use is the diaphragm for one fundamental safety reason: the risk of cerebral gas embolism.

If CO₂ were injected into arteries above the diaphragm, small gas bubbles could reach the brain, causing stroke or transient neurological deficits.

Why it's safe below the diaphragm: When CO₂ is injected into the abdominal aorta or leg vessels:

1. The gas naturally tends to rise upward
2. It is progressively diluted in venous blood
3. It reaches the lungs where it is completely eliminated through respiration
4. It cannot reach the cerebral or coronary arteries
   
   

An arteriovenous fistula (AVF) is a surgical connection created between an artery and a vein, usually in the forearm, in patients who require chronic dialysis. This connection:

• Increases blood flow in the vein
• Makes the vein larger and more resilient
• Allows needles to be inserted for dialysis multiple times per week

• Stenosis (narrowing) that reduces flow
• Thrombosis (occlusions)
• Need for frequent monitoring and interventions to keep them functioning

• In patients with residual kidney function, could further damage it
• Would require additional dialysis sessions to remove the contrast
• Would limit the frequency of monitoring

• Frequent monitoring can be performed without damaging residual kidney function
• No additional dialysis is needed to eliminate the contrast
• The fistula can be monitored and treated as often as necessary