kaolinite and Necrosis

Severe hepatic injuries may be highly lethal, and perihepatic packing remains the mainstay of treatment. This is not always successful, particularly in the setting of hypothermia and coagulopathy. Kaolin-impregnated Combat Gauze (CG) is an effective hemostatic dressing used primarily to treat external wounds. The objective of this study was to determine the ability of CG to control severe hemorrhage in hypothermic, coagulopathic swine with a high-grade hepatic injury.. Anesthetized animals underwent splenectomy and were cooled to 32°C while undergoing a 60% exchange transfusion with Hextend. A grade V liver injury was created in the left middle hepatic lobe. Animals were allowed to freely bleed for 30 s and then randomized to treatment with CG or plain gauze laparotomy pads (PG) applied to the injury site. Animals were then resuscitated with warmed Hextend.. There was no difference between groups in preinjury hemodynamic or laboratory values. Animals packed with CG had less blood loss when compared with standard packing (CG = 25 mL/kg versus PG = 58 mL/kg, P = 0.05). There was a trend towards lower hetastarch resuscitation requirements in the CG group (CG = 7 mL/kg versus PG = 44 mL/kg, P = 0.06) but no statistically significant difference in mortality (CG = 13% versus PG = 50%, P = 0.11). Histology of the injury sites revealed more adherent clot in the CG group, but no inflammation, tissue necrosis, or residual material.. In pigs with severe hepatic injury, Combat Gauze reduced blood loss and resuscitation requirements when compared with plain laparotomy pads. Combat Gauze may be safe and effective for use on severe liver injuries.

Topics: Animals; Bandages; Blood Coagulation Disorders; Disease Models, Animal; Female; Hemorrhage; Hemostatic Techniques; Hemostatics; Hypothermia, Induced; Incidence; Inflammation; Kaolin; Liver; Male; Necrosis; Pilot Projects; Swine; Treatment Outcome

Topics: Amputation, Surgical; Animals; Antidiarrheals; Boric Acids; Buffaloes; Dermatologic Agents; Gangrene; Insecticides; Kaolin; Necrosis; Powders; Tail; Zinc Oxide

We studied the origin of the epithelioid cells (macrophages) observed in the rat brain in response to the intracisternal injection of kaolin. The rats, two days of age, were used. The animals were killed after thirteen weeks following cisternal injection of kaolin. Massive epithelioid cell-nodes with multifocal necrosis were seen in the subarachnoid space of the cerebellum, in the cerebellar parenchyma and in the fourth ventricle. They were also present in the choroid plexus. The papillary epithelioid cell-nodes were observed onto the aqueduct of Sylvius, the third and lateral ventricles. These were associated with the proliferation of the adventitia of the blood vessel in the subependymal white matter. This suggested that the vascular adventitia played a role for a formation of the epithelioid cell-node in this case. The epithelioid cell was negative in silver-stained preparation. This indicated that microglia was not a source of the epithelioid cell. Reticulin fibers were moderately increased in the lesions. The epithelioid cells phagocytized kaolin granules and gave a strong PAS-positive reaction. However, it seemed that the PAS-positive materials were not identical to the kaolin granules. A rich accumulation of apparently extra- and intracellular kaolin deposits stained metachromatically violet with toluidine blue was seen in the necrotic areas. A large number of the degenerated cells containing kaolin deposits was found especially in the marginal zone of the necrotic areas. Granulation tissue with the amount of spindle-form cells and collagen fibers was also observed in the subarachnoid space. The granulation tissue was formed by hyperplasia of fibroblasts following the proliferation of the epithelioid cells and their necrotic processes.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Brain Diseases; Cisterna Magna; Disease Models, Animal; Epithelium; Granuloma; Injections; Kaolin; Macrophages; Meningoencephalitis; Necrosis; Rats; Rats, Inbred Strains

Topics: Acetates; Adaptation, Physiological; Animals; Cross Reactions; Female; Histamine; Histamine Release; Injections, Intravenous; Kaolin; Mast Cells; Necrosis; p-Methoxy-N-methylphenethylamine; Polymyxins; Polysaccharides; Rats; Serotonin; Vasopressins

Topics: Acetates; Animals; Dextrans; Epinephrine; Histamine; Hypersensitivity, Immediate; Kaolin; Necrosis; Norepinephrine; Polymyxins; Polysaccharides; Rats; Serotonin; Sodium Chloride; Vasopressins