Barium meals

Other chemical applications of barium sulfate are as the opaque ingredient in a barium meal for x-ray diagnosis as a pigment for photographic paper and to prepare many barium salts. 

There are a few common and long-known uses of heavy metal compounds which should be mentioned. The barium meal is used in gastrointestinal X-rays. It is administered as barium sulfate, the high electron scattering of barium ions providing X-ray opacity. Mercurial diuretics, derivatives of propan-2-ol, work by inhibition of sulfhydryl enzyme sites. These compounds are now becoming obsolete, however. 

Barium sulfate BaS04 Barium meal used in diagnostic medical X-ray studies... 

Simmonds RJ, James AM. 1976. An in vivo investigation of barium meals. Cytobios 16 13-21. 

Barium, like all elements with large atomic number, absorbs X-rays strongly, and a thin paste of barium sulfate and water is swallowed as a barium meal to obtain contrasting X-ray photographs and fluoroscopic views of the alimentary tract. The solubility of the substance is so small that the poisonous action of most barium compounds is avoided. 

Barium sulfate (barite) barium chloride the barium meal. ... 

Oral barium sulfate is theoretically non-toxic, but constipation and abdominal pain are not uncommon after barium meals or barium enemas (1). The main risk is that collections of barium wiU remain in the colon they can persist for 6 weeks or longer in elderly patients or cases of colonic obstruction barium fecoliths may even have to be removed surgically. Prolonged stasis of barium can occur after a barium enema into the distal loop of a colostomy. Residues in the appendix have caused appendicitis. Toxic dilatation of the colon can be aggravated by barium sulfate. 

Aspiration of barium sulfate into the lungs during barium meal examination can cause significant respiratory embarrassment, particularly in patients with poor respiratory function. It is recommended that water-soluble low-osmolar contrast media, which are less harmful, should be... 

Perforation can occur elsewhere than in the colon in one case a duodenal ulcer was apparently made to perforate. In both this and another case of perforation of a sigmoid diverticulum the complication was not immediately recognized, the duodenal perforation only being detected 5 days after administration of the barium meal (SEDA-17, 535). 

Hypersensitivity reactions to products used during barium meal examinations are extremely rare. Barium sulfate is generally regarded as an inert and insoluble compound that is neither absorbed nor metabolized and is eliminated... 

Stringer DA, Hassall E, Ferguson AC, Cairns R, Nadel H, Sargent M. Hypersensitivity reaction to single contrast barium meal studies in children. Pediatr Radiol 1993 23(8) 587-8. 

Indications Diagnostic aid for gall bladder function, pancreatic function, accelerating transit of barium meal Category Diagnostic aid Hormone Polypeptide Half-life 6 hours... 

Many different preparations of colloidal barium sulfate for roentgenography are available commercially. The so-called barium meals are not limited to liquid suspensions they also appear as tablets (73). Barium sulfate suspensions containing an effervescent agent have been introduced for use in doublecontrast studies (74,75). Barium sulfate may also be coated with Fe203, MgO, and Al Oa (63,761. The coated material has good dispersibility and very low viscosity in acidic media. Other barium preparations are also useful. A barium titanate suspension was compared with barium sulfate (72). An emulsified mixture containing castor oil and barium sulfate can visualize colon fistula more economically than can iodinated contrast media (77). 

Nuclear power plant to critical group (Sweden) X-ray investigation barium meal (intestine) intravenous urography abdomen and lung mean gonadal dose (abdomen), genetically significant dose dental... 

Orally administered peppermint oil was used in a randomized trial in 430 patients undergoing a double-contrast barium meal examination, without other antispasmodics. A reduction in spasms... 

Mizuno, S., Kimitoshi, K., Yoshiki, 0. et al. 2006. Oral peppermint oil is a useful antlspasmodic for double-contrast barium meal examination. 21 1297 1301. 

Orally administered peppermint oil was used in a randomized trial in 430 patients undergoing a double-contrast barium meal examination, without other antispasmodics. A reduction in spasms of the esophagus, lower stomach, and duodenal bulb was found, along with an inhibition of barium flow to the distal duodenum and an improvement of diagnostic quality (Shigeaki et al., 2006). 

A barium meal before an X-ray is used to diagnose cancers and ulcers in the intestine or stomach (Figure 17.15). The patient drinks a barium meal (barium sulfate and water) before having the X-ray taken. Aqueous barium ions, Ba (aq), are highly toxic. However, the barium meal is not poisonous because barium sulfate is highly insoluble - this is indicated by its very low solubility product (K p = 1.08 x 10 - IB Chemistry data booklet). 

Figure 17.15 A coloured photograph of the entrance to the duodenum showing the blocking of the passage of the barium meal by an ulcer In the centre... 

When a patient drinks a barium meal, an aqueous suspension of BaS04, his or her digestive tract becomes opaque to X rays and affords an excellent diagnostic tool. 

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