Final answer:
For an 8-month-old patient undergoing an upper GI series, the recommended amount of barium, a barium sulfate suspension, is 2-4 ounces. This allows for clear X-ray imaging of the gastrointestinal tract without significant absorption into tissues.
Step-by-step explanation:
For an 8-month-old patient undergoing an upper GI series, a commonly recommended volume of barium is 2-4 ounces (oz.). This range can vary depending on the size and clinical needs of the patient and is intended for safe and effective visualization of the gastrointestinal tract. The barium used in this procedure is a suspension known as a "barium milkshake", which includes very fine barium sulfate (BaSO4) particles in water. Barium sulfate's low solubility and high atomic mass make it opaque to X-rays and hence, an excellent contrast agent for these types of medical imaging procedures. However, it's essential to adhere to recommended dosages, specifically tailored for infants to minimize any potential risks, as soluble barium salts can be toxic. Fortunately, barium sulfate is so insoluble that it is not absorbed into tissues, making it a safe option for diagnosing stomach and intestinal issues through X-ray imaging.