CHARLES E. DE Al. SAJOLTS, Philadelphia.
NITRIC nitricum, S. P. (hydrogen nitrate, or aqua fortis), is a transparent, colorless (or of slightly yellow tinge), fuming (white or grayish fumes), suffocating, and caustic liquid, strrngly acid and volatile with heat. It -hould have a specific gravity of 1.414 (12° liauni6) and contains GS per cent. of absolute acid. It is miscible in all pro portions with water, and when added to alcohol decomposes it with violence. It should be kept in a dark-amber, glass stoppered bottle, as it is decomposed by the action of light and air. It is the strongest of the mineral acids, and is usu ally exhibited in the dilute form.
Preparations and Doses. — Acidum nitricum dilutum (nitric acid, 10 per cent.), 5 to 30 minims.
Acidum nitrohydrochloricum (nitric acid, 18 per cent.; hydrochloric acid, 82 per cent ), 2 to 5 minims.
Acidum nitrohydrochloricum dilutum (nitric acid, 4 per cent.; hydrochloric acid, 18 per cent.), 10 to 20 minims.
Physiological Action.—In weak solu tion nitric acid slightly stimulates the tissues, but applied pure it destroys them, and is, on this account, classified as a very powerful caustic. Internally it can, of course, only be used greatly diluted, and its powers as a stimulant manifest themselves mainly upon the glandular elements of the gastro-intestinal tract. When taken internally for some time, nitric acid colors the gums as does mer cury.
A very small proportion, if any, of the acid is eliminated through the kidneys; it is eliminated almost entirely through the intestines.
It is probable that nitric acid enters the blood, where it is converted into a ni trate. Some of the organic nitrates have been shown by Bradbury to stimulate the vasomotor system, the glycol-dinitrate, for instance, acting somewhat like nitro glycerin. This effect varies with the in dividuals, some showing comparative in susceptibility. Other nitrates act tran siently as vasodilators.
Poisoning by Nitric Acid.—The symp toms of poisoning by nitric acid, in con centrated form, are those of an acute and violent inflammation of the digestive tract induced by the ingestion of a caustic irritant. They vary in severity and rapid ity of development according to the strength and amount of the acid swal lowed. The fact that when nitric acid comes in contact with organic matter it imparts to it a yellow color or stain, not easily removed, aids us in differentiating the traces of nitric acid from those of sulphuric (black eschar) or hydrochloric (white eschar) acid. Thus, we may look
for yellow stains on the skin, in the mouth, and perhaps on the clothing. Great pain will be present throughout the entire digestive tract, associated with vomiting of a dark matter, resembling coffee-grounds (altered blood), and occa sionally portions of mucous membrane; a feeble pulse, clammy skin, and profuse bloody salivation. Renal irritation may be severe and the- urine and fmces may contain blood more or less altered. Death may occur either from the gastro-intes tinal inflammation or from collapse. If recovery take place the patient may suffer from stricture of cesophagus, stomach, or bowels, or from more or less destruction of the peptic tubules.
Death from inhaling nitric-acid fumes in one of four firemen attending a fire during which they were exposed to these fumes through the breaking of a carboy. A broncho-pucumonia developed with subsequent wderna of the lungs, and death occurred twenty-nine hours later. The other firemen suffered but slightly and recovered completely in twenty-four hours. 1I. S. Pearse (Albany Med. An nals, Jan., '99).
Treatment of Nitric-Acid Poisoning.— There are four indications to be met: (1) to neutralize the acid through the use of alkaline solutions,—chalk mag nesia, sodium or potassium carbonates, scrapings from whitewash or plastered Ivalls, or even soap-suds; (2) to protect mechanically the corroded and inflamed tissues, through the use of white of egg, oils, and mucilaginous drinks (flaxseed tea, barley-water, etc.); (3) to relieve the pain, through the use of opium; (-1) to counteract the depression of the vital powers, through the application of ex ternal heat, the use of stimulating and nutrient enemata, and venous injections of ammonia. If pure acid in any consid erable amount has been ingested, favor able results must not be looked for. The smallest quantity of nitric acid that has produced death was two drachms. Death ensiled in two hours. Fatal accidents occasionally result from inhaling the fumes of nitric acid.