Discontinuation of the Plastic Bag Delivery System for Carbon Dioxide Angiography Will Increase Radiocontrast Nephropathy and Life-Threatening Complications

Abstract

AJR:197, November 2011 pure CO2 may have contaminants, such as rust, methane, and particulate matter. We recommend using a disposable aluminum or a stainless steel cylinder that has not been previously used and has been individually tested for purity. Some of the cylinders available for anesthesia may contain 80% oxygen and 20% CO2. If CO2 cylinders are purchased from other vendors, they should be tested for purity with a mass spectrometer (usually available in anesthesia departments) or using an inexpensive chemical reagent tube (Colorimetric Gas Detector Tube, Sensidyne). If an excessive volume of CO2 is injected into the venous side of the circulation, blood will be displaced from the right heart and pulmonary artery, resulting in a vapor lock phenomenon and possibly cardiac arrest. If excessive amounts are injected into the arterial system, there can be reflux into unwanted areas, such as the cerebral or coronary circulation, which might be lethal. Again, the cylinder should never be connected directly to the patient because even with the plastic bag system CO2 could rapidly flow into the vascular circulation. If the syringe is filled directly from the cylinder, the pressurized CO2 will expand in the vessel causing reflux into the adjacent vessel and discomfort to the patient. No system should include stopcocks, which could be inadvertently malpositioned, or additional 3-way stopcocks to fill the plastic bag system. The 1500-mL bag contains more than enough volume for most diagnostic and interventional procedures. If the bag is filled only to atmospheric pressure (flaccid), the amount of CO2 aspirated into the syringe is always accurate in volume. A closed airtight system is absolutely necessary because the partial pressure difference between the syringe CO2 and room air will result in rapid diffusion of room air into the syringe if the stopcock is left open [4]. Any system with stopcocks should not be used because the stopcock could be left open Discontinuation of the Plastic Bag Delivery System for Carbon Dioxide Angiography Will Increase Radiocontrast Nephropathy and Life-Threatening Complications