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INTRODUCTION: Barium sulfate (BS) is chosen to explore swallowing disorders because of its reduced osmolality allowing no adverse reaction if aspirated in the bronchial tree. CASE REPORT: A 66-years old man treated for an advanced stage mesothelioma experienced a BS aspiration during an esophagography. He developed 3 days after an acute respiratory distress syndrome (ARDS) and deceased. The post-mortem examination revealed a diffuse alveolar damage (DAD). CONCLUSION: Whereas BS aspiration is generally well tolerated, serious adverse event as a DAD would exceptionally occurs. Thus, a close watch over respiratory symptoms has to be kept after BS administration, especially in debilitated and elderly patients.
Barium peritonites are known to be a serious complication of barium enema examinations, being accompanied by a high mortality rate. The authors made their study injecting barium and radioactive 133Ba in the peritoneum of 68 rats without causing damages to the colon, in order to verify the toxicity of barium if injected in the peritoneum, and to evaluate the various extraperitoneal locations. Moreover, they compared the alterations caused by this agent with those consequent to a similar agent, such as talcum. The results show that barium is not toxic on its own: it gives in fact origin to granulomas similar to those caused by talcum; a particular tropism for the lymphatic tissues is present as well.
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In vitro proton spectroscopy with line-width measurements and MR imaging were performed on various concentrations of commercially available single contrast (SC), double contrast, oral and rectal barium sulfate suspensions, as well as potassium sulfate, barium chloride, barium hydroxide, and 97% pure barium sulfate suspensions. Approximately 500 ml of 20%, 40%, 60%, and 70% w/w suspensions of SC oral barium sulfate suspensions were administered to four normal volunteers, respectively, and MR images were obtained at both 1.5 T and 0.15 T. Subsequently, 500 ml of 60% w/w suspensions of SC oral barium sulfate suspensions were administered to five normal volunteers and imaged at 1.5 T. All of the inert suspensions produced line-width broadening but the SC oral barium sulfate suspension at 50% and 70% stayed in suspension even after hours of standing undisturbed. As much as 80% of the small bowel and the entire colon were well visualized using the combination of 60% or 70% w/w SC barium sulfate suspensions with SE 550/22 and FISP pulse sequences. The effect was less at 0.15 T and also with the SE 2000/45/90 pulse sequences. We conclude that barium sulfate suspensions are useful as oral MRI contrast agents.
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Barium sulfate, used as a radio-opaque marker in some orthopedic bone cements, has been shown to escape into the surrounding tissues. This may present a potential hazard. In particular, phagocytic cells may be exposed to relatively high internal levels of barium once the particles have been phagocytosed. Mouse peritoneal macrophages exposed to barium sulfate for periods up to 144 hr showed a marked cytoplasmic vacuolization from which they recovered only partially. Barium sulfate did not appear to damage the cell membrane as judged by lactice dehydrogenase release. In the relatively low doses and with the periods of exposure described here, barium sulfate does not appear to present a serious toxic hazard in the short term. It is possible, however, that longer exposures and larger doses may result in the death of phagocytic cells which have ingested barium sulfate.
Alveolarization of the barium sulfate and subsequent retention of barium sulfate for years was demonstrated in three patients in whom dilute suspension of barium sulfate in water was used for bronchography. Pathologic examination in one patient showed barium sulfate within macrophages in the alveolar spaces and walls and in the perivascular and peribronchial interstitium. Since the residual barium sulfate interferes with imaging procedures of the lungs, it represents an unwanted event in patients with pulmonary disease. High-resolution computed tomography is the preferred method of evaluating for bronchiectasis. If bronchogram is performed, it should be performed after bronchoscopy using oily propyliodone (Dionosil).
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Intragastric administration of barium sulfate to albino rats did not produce deaths until the dose reached 25% to 40% of body weight. Death was due to stomach rupture or to bowel obstruction followed by gastrointestinal hemorrhage and generalized arteriovenous thromboses which produced further toxic changes in many body organs. Barium sulfate does not appear to be a factor of significance in the acute toxicity of tannic acid-barium sulfate formulations used in diagnostic radiology.
Characteristics of barium sulfate contrast agents used in roentgenographic studies are described. Barium sulfate can be used as a single contrast agent in the gastrointestinal tract; it can also be used for positive contrast in studies that use air for negative contrast (double-contrast examinations). Barium sulfate can be used to opacify the GI tract in preparation for computerized tomography of the abdomen. Barium sulfate products are available in powder form or as viscous suspensions. Product formulas and barium sulfate concentrations are varied to produce adequate coating and visualization of the portion of the GI tract to be examined, and the dosage is determined by the specific procedure. Double-contrast studies delineate fine details of the GI mucosa; preparations used in these studies contain smaller barium particles than those used in single-contrast studies. Agents that produce carbon dioxide are usually administered for double-contrast studies; the gas distends the stomach or intestine so the barium can cover the entire surface. Formulations of barium sulfate products vary so that a product appropriate for the specific procedure can be selected. These products also vary in cost, ease of reconstitution, and, for oral preparations, acceptability to patients.
McFarland barium sulfate standards prepared in 1952 were compared spectrophotometrically with freshly and identically prepared standards; the results were nearly identical.
Luminol dependent stimulated by barium sulfate crystals chemiluminescence of leukocytes in the whole blood was studied. Chemiluminescent kinetics and dependence between the chemiluminescence intensity and temperature were investigated. The chemiluminescence is related to the formation of reactive oxygen by stimulated leukocytes which settled to the bottom of the cell together with the crystals of barium sulfate.
A surface characterization of barium sulfate particles in aqueous suspensions was carried out in this work. With the aim of predicting the stability conditions of these widely used suspensions, the electrical surface properties of the particles were first studied by electrophoretic mobility determinations. It was found that both H(+) and OH(-) ions can be considered as potential-determining ions for the barium sulfate/water interface. The same conclusion was reached concerning the lattice ions, Ba(2+) (mainly) and SO(4)(2-). It was also found that increasing the concentration of sodium chloride in the dispersion medium can even change the sign of the zeta (zeta) potential: it is suggested that this behavior is an indirect effect provoked by changes in the solubility of barium sulfate with the ionic strength. To compute the van der Waals (LW) attraction between the particles as well as the acid-base contribution to the total energy of interaction, a thermodynamic characterization of the interface was also carried out by measuring the rate of penetration of selected liquids through plugs of the particles. It was found that barium sulfate particles are essentially monopolar in nature; that is, they show electron-donor character as demonstrated by the essentially zero value of the electron-acceptor component of their surface free energy. Pretreatment of the particles with 10(-2) M solutions of BaCl2 and CaCl2 significantly reduced the electron-donor component, whereas both NaCl and Na(2)SO(4) provoked the opposite effect. This result is explained in terms of the acid-base character of the ions added. These data were used to calculate the interaction energy between the particles. The effect of electrolyte concentration on the stability of the suspensions was analyzed on the basis of the dependence with distance of the interaction energy between the particles. Our results suggest that more stable suspensions of barium sulfate are predicted if moderate amounts of SO(4)(2-) ions are added to the dispersion medium.