Angiography is a diagnostic medical imaging technique that uses a special contrast material and X-rays to see how the blood flows through major organs, such as the heart and brain. In CO2 angiography, instead of using a radio-opaque dye, carbon dioxide is used as the contrast material. This procedure is effective in diagnosing peripheral vascular diseases. Carbon dioxide as a dye also produces less allergic reactions. There are several potential CO2 angiography complications.
Respiratory Depression
According to the National Institute on Drug Abuse, sedatives and anesthetics used in carbon dioxide angiography can potentially cause respiratory depression. This condition, also known as hypoventilation, is characterized by a slow respiratory rate and a significant decrease in the urge to breathe. Hypoventilation can cause an increase in carbon dioxide concentration as well as respiratory acidosis. Air contamination with carbon dioxide during the procedure can also lead to respiratory depression. To reduce the risk for such complication, doctors control the use of heavy sedatives and analgesics.
Hypotension
Hypotension, or low blood pressure, can occur as one of the possible complications of carbon dioxide angiography, as described in the National Heart Lung and Blood Institute. Normal blood pressure in healthy adults is 120/80 mm HG; hypotension is a blood pressure reading that goes lower than 90/60 mm HG. Hypotension is brought about by the body's reaction to certain medications such as sedatives and analgesics. During carbon dioxide angiography, controlled substances such as morphine derivatives are used as an anesthetic agent. One of the effects of this medication is hypotension. Lowering of the blood pressure is also believed to be caused by air contamination with carbon dioxide. Sedatives and analgesics are used sparingly to avoid the incidence of hypotension.
Air Embolism
According to MedlinePlus, air embolism can occur as one of the complications of carbon dioxide angiography. Air embolism, also called gas embolism, is caused by accidental tubing disconnection or separation of the carbon dioxide injector from the blood vessel. Gas leaks on the area being treated can also this condition. Air embolism is characterized by chest pain, breathing difficulties and loss of consciousness. Patients who experience air embolism are instructed to lie on the left side with head lower than the feet for a few minutes. Doctors can withdraw the air emboli with the use of a pump or syringe.
