tailieunhanh - Trauma Resuscitation - part 9

Bệnh nhân đã được quỳ trong xi măng. Oxit canxi trong xi măng phản ứng với nước để sản xuất hydroxit canxi. Đây là hydroxit canxi gây ra vết bỏng. Bức ảnh này thể hiện đẹp khu vực áp lực tối đa, từ đó nước và xi măng đã bị trục xuất, đã được tha. | 272 TRAUMA RESUSCITATION Figure Cement burns. The patient had been kneeling in cement. The calcium oxide in cement reacts with water to produce calcium hydroxide. It is the calcium hydroxide which causes the burn. This photograph demonstrates beautifully that the area of maximum pressure from which water and cement were expelled has been spared. seen are due to cement Figure . More than 50 of chemical burns are now due to domestic products often oven and drain cleaning compounds. Less than 5 of all such injuries require admission. COSHH regulations stipulate that Safety Data Sheets should be available for all industrial processes With two notable exceptions chemical burns can largely be divided into those caused by acids those caused by bases or alkalis and those caused by organic hydrocarbons. Acids produce coagulative necrosis similar to a thermal burn and as such prevent deep penetration of the burning agent through formation of an eschar. Alkalis in contrast cause injury through liquefactive necrosis and saponification of fats and penetrate deeper into tissues. Organic hydrocarbon compounds such as petrol can cause a chemical burn without ignition by liquefaction of lipids. Hydrofluoric acid is used in glass etching fluorocarbon manufacture PTFE and high-octane fuel manufacture. In burns caused by hydrofluoric acid the fluoride ion is absorbed and chelates calcium and magnesium ions causing bone demineralization cell death and potassium release. The fall in serum calcium and rise in serum potassium can be very rapid and lead to arrhythmias refractive VF and death. Of note hydrofluoric acid burns can be fatal at less than TBSA. White phosphorus burns are largely seen in the military where the compound is used as an igniter in ordnance and in tracer rounds. Phosphorus ignites on contact with air. It is extremely fat soluble and produces yellow blisters with a characteristic garlic smell. If absorbed hepatorenal toxicity may occur and death has been