Memoranda on Poisons Part 11

There is commonly a wide difference between teta.n.u.s arising from a wound or from disease and that provoked by strychnia. In the former case some exciting cause can be detected; the symptoms come on gradually, and only attain their full development at the end of several hours; the rigidity of the muscles is more or less permanent, there being no intervals of relaxation as there are in poisoning; and death has hardly been known to occur in less than twenty-four hours, while frequently it is deferred for two or three days.

_Post-mortem Appearances._-Although the body may be relaxed at the time of death it usually quickly stiffens-frequently in the course of ten or fifteen minutes. The rigor mortis is persistent for some time: in the case of Cook, poisoned by Palmer, the rigidity of the body and limbs was said not to have pa.s.sed off after two months' interment. This is not however invariable, as a body may be flaccid or stiff after death from this cause as from any other. The hands are often clenched, and the soles of the feet arched and inverted. The membranes of the brain and of the upper part of the spinal cord are congested; and there is often considerable serous effusions under the spinal arachnoid. The lungs are generally loaded with dark fluid blood. The heart is usually contracted, but sometimes the right cavities are distended like the pulmonary vessels. The blood has been found black and liquid.

_Treatment._-Emetics are to be given at once, and repeated until very free vomiting is induced. If the tetanic spasms have not commenced, the stomach-pump ought to be used. Chloroform is to be given to relieve spasm and pain, but the patient should be disturbed as little as possible, as the least thing induces the tetanic attack. There is no very suitable antidote, but tannic acid, in the form of green or black tea, &c., might be given.

Iodine forms a crystallizable compound with strychnia. Dr. Bennett, of Sydney, has recorded an instance in which he attributed recovery to the employment of tincture of iodine. Hence from thirty minims to a drachm of this tincture combined with the iodide of pota.s.sium may be exhibited.

In its absence, three or four ounces of animal charcoal, diffused through water, ought to be given.

To prevent the spasms by paralyzing the motor nerves, a solution of curare has been recommended by Dr. George Harley to be injected under the skin; or, if it could be obtained, the active principle of this substance, curarina, would perhaps be deserving of trial.

The patient is to be kept warm and quiet.

To separate strychnia from organic admixture the process modified from Stas, given in the beginning of this book, is the most useful.

_Tests._-Strychnia is a white crystalline solid, very insoluble in water, soluble in alcohol or chloroform or weak acids, and having an intensely bitter taste.

1. Pure strychnia is not changed in color when treated with iodic acid or with either of the strong mineral acids; but as this alkaloid generally contains brucia, nitric acid reddens it.

2. Dissolved in sulphuric acid no change ensues; but on adding a fragment of b.i.+.c.hromate of pota.s.s to the solution a series of blue, violet, purple and red tints are produced. The same result is brought about by using ferricyanide of pota.s.sium, permanganate of pota.s.sium, the peroxide of lead, or the black oxide of manganese.

3. If the skin of a frog be dried, and a few drops of a solution containing strychnia applied to it, strong tetanic convulsions will ensue, and be reproduced every time the animal is touched or irritated.

According to Dr. Marshall Hall this strychnoscopic test will detect the 1/5000th of a grain, or even less.

4. An exceedingly useful cla.s.s of tests for many poisons has been introduced by Dr. Guy; we mean the crystalline appearances presented on subliming the substance and condensing it on a cool microscopic slide, or the crystalline form observed as modified by various reagents. Thus the strychnine sublimate, touched with a drop of carbazotic acid, forms groups of arborescent crystals, each branch forming part of a circle, when seen under the microscope.

CHAPTER XXVII.

HYPOSTHENISANTS.

NEUROTICS PRODUCING DEATH BY SYNCOPE.

ACONITE-PRUSSIC ACID.

ACONITE (_Aconitum Napellus_, _Monkshood_, _Wolfsbane_, _Blue Rocket_).-This beautiful plant is found in most parts of Europe.

_Aconitia_, the alkaloidal base of the plant, is the most deadly poison known; the fiftieth part of a grain having nearly caused death.

The chief _symptoms_ of poisoning by aconite are numbness and tingling in the mouth and throat, giddiness, abolition of muscular power, pain in the abdomen, with vomiting and purging. Sometimes delirium and slight stupor have been noticed. The pupils are usually dilated, the skin is cold, the pulse exceedingly feeble, the breathing oppressed, and there is a dread of approaching dissolution. Frequently the sufferer is perfectly conscious, though paralyzed, till death suddenly occurs after two or three hurried gasps. According to Dr. Fleming, death may be due to a sedative impression on the nervous system, or to asphyxia from paralysis of the respiratory muscles, or to syncope.

A fatal mistake is not very uncommonly made in eating the root of aconite for that of horseradish. The sense of tingling and numbness produced by the former is so different from the pungent taste of the latter that with due care no mistake should occur, except the plants be allowed to grow together, which should never be done.

A case occurred in Ireland where a woman poisoned one man and nearly killed another by sprinkling powdered aconite root over a dish of greens.

Of the root one drachm, of the tincture one drachm, and of the alcoholic extract four grains, have caused death. Death follows a considerable dose in less than an hour, but sometimes a longer period elapses.

The Bikh poison, formerly much used in India, and still not unfrequently employed, has as its basis the Aconitum ferox, a still more dangerous drug than our indigenous plant.

_Treatment._-No time must be lost in the use of remedies. In addition to emetics, castor oil, and animal charcoal, benefit may be derived from administering strong coffee. Brandy or ammonia should also be given, while the limbs and back are well rubbed with hot towels. Artificial respiration might prove useful.

There is no good test for aconitia.

HYDROCYANIC ACID (_Prussia Acid_), on account of its energetic and rapid action, is one of the most formidable poisons with which we are acquainted. In its concentrated state it is a limpid colorless liquid; possessing a somewhat acrid taste, and having an odor, when diffused through the air, resembling that of oil of bitter almonds. When diluted with water, it forms the acid kept by the druggist. The properties of this variety are similar to those of the pure form; except that, if kept in the dark, it is not so readily decomposed. It is in this condition that it is used as a poison. The diluted acid of the British Pharmacopia contains about 2 per cent., and that known as Scheele's from 4 to 5 per cent., of the strong acid; but all vary greatly with keeping.

One of the salts of hydrocyanic acid, the _cyanide of pota.s.sium_, claims a short notice, since it is largely employed by photographers, workers in electrotype, &c. It has been taken as a poison. This salt is sold in the form of deliquescent white crystals, or in crystalline ma.s.ses, which are very soluble in water, and possess the odor of prussic acid. From three to five grains will destroy life almost as rapidly as prussic acid itself, and in the same manner: a dose of five grains has proved fatal.

Several vegetable substances yield prussic acid, such as the kernels of the peach, apricot, nectarine, cherry, &c., the leaves of the cherry laurel, and the pips of apples and pears. Cases of alarming illness have occurred from eating _bitter almonds_ too freely; while the essential oil obtained by distilling the pulp of these almonds with water is a powerful poison. This _essence_ or _oil of bitter almonds_ contains about ten per cent. of anhydrous prussic acid; and it is probable that from ten to thirty drops would prove fatal to an adult. The prussic acid may, however, be separated from it, and leave the oil harmless.

A distilled water obtained from the leaves of the cherry laurel, which was formerly employed in medicine, proved dangerous from its very variable strength; it has been used as a poison. In the well-known case of Sir Theodosius Boughton, poisoned by Captain Donellan in 1781, _laurel water_ produced death within half an hour after two ounces had been swallowed.

The smallest quant.i.ty of prussic acid which has been known to destroy life is nine-tenths of a grain of the anhydrous acid, equal to forty-five minims of the diluted preparation of the British Pharmacopia; and it is probable that this would, in most instances, prove fatal. In the case referred to death occurred in twenty minutes; but from a larger dose it has ensued much earlier. The period may be said to vary from two to five and forty minutes. Insensibility may, however, come on in a few seconds. In the case of seven epileptics accidentally poisoned at the Bicetre, death occurred in the first within twenty minutes, in the last after three-quarters of an hour, though the dose of the acid was the same in each instance.

_Symptoms._-These will vary with the dose and the mode of exhibition.

Inhalation of the vapor of anhydrous prussic acid would immediately cause death. The vapor of the diluted acid has given rise to serious symptoms with great rapidity. Scheele is said to have been suddenly killed by respiring the vapor of the dilute acid while making his experiments.

When the diluted acid is taken in a large dose the symptoms may commence during swallowing, death following so quickly that scarcely any effects can be observed. The chief symptoms, perhaps, are insensibility, slow gasping, or convulsive respiration, a clammy cold skin, fixed and glistening eyes, dilated pupils, spasmodic closure of the jaws, an almost imperceptible pulse, and sometimes convulsions of the limbs and trunk. The rapidity with which consciousness is lost is well exemplified in an instance recorded by Hufeland, where a man about to be apprehended as a thief took an ounce of the acid, staggered a few steps and fell apparently lifeless. In a few moments a single violent respiration was made, and within five minutes of taking the poison he was dead.

Insensibility is not, however, in all instances, immediately produced; many an authenticated case having occurred in which the symptoms were protracted for some minutes, the individual performing several acts indicating consciousness, such as replacing the cork in the bottle, adjusting the bed-clothes, or even running some distance to summon help.

The utterance of a shriek has been said to be characteristic of poisoning by this acid; but toxicologists know that such has not been observed in the human subject, and that there is merely a gasping for breath, or perhaps a call for help.

A small dose produces faintness, insensibility, difficulty of breathing, involuntary evacuations, loss of muscular power, convulsions, and temporary paralysis. If the proper treatment be employed, recovery may often be effected.

_Post-mortem Appearances._-The body is generally livid, the countenance pallid, or sometimes livid and bloated, the jaws firmly closed, and the hands clenched. There is frequently blood or froth about the mouth, and the eyes are sometimes described as prominent and glistening. There is often an odor of prussic acid about the body, which is more perceptible on opening the stomach. The venous system is usually gorged with blood; and the brain, lungs, heart, liver, spleen, and kidneys have been found congested with dark-colored fluid blood.

_Treatment._-There is no chemical antidote to this poison which can be relied upon. Chlorine and the mixed oxides of iron have been recommended; but even if one of these agents happened to be at hand, it is doubtful if its employment could be timely enough to be advantageous.

Attempts must be made to restore animation by cold affusion, stimulating frictions to the chest and abdomen, warmth to the surface, and the application of ammonia to the nostrils. Cold affusion over the head and neck has proved most efficacious when promptly resorted to, and repeated at short intervals so as to cause a shock. The direct injection of liquor ammoniae into the veins, as proposed by Professor Halford, for snake bite, might be tried if the means were at hand. As soon as possible ammonia should be given internally and the stomach emptied.

If recovery ensue from the immediate effects, vomiting should be produced by emetics or otherwise, after which strong coffee, with brandy, ought to be administered.

_Tests._-The best are the following:

When hydrocyanic acid has to be separated from organic substances, such as the contents of the stomach, it is usual to take advantage of its ready volatility. If the acid be not in combination it may be given off so readily as to be detected by a watch gla.s.s moistened with nitrate of silver held over the vessel containing the acid; but in order to make sure of its presence or absence the following process should be adopted.

The suspected material should be acidulated with pure sulphuric acid so as to insure the prussic acid being in a free state. The substances thus acidulated are to be placed in a retort, distilled over a water bath, and the distillate collected in a cool receiver containing some caustic pota.s.s. About one-sixth of the fluid substance should in this way be distilled over, when the liquid in the receiver may be tested by the silver or iron tests, or the vapor as it pa.s.ses over may be tried with the sulphur test.

1. The peculiar _odor_ of prussic acid is well known, and is a very delicate test, taken in conjunction with others, of its presence.

2. _The Silver Test._-Nitrate of silver yields, with hydrocyanic acid or cyanide of pota.s.sium, a white clotted precipitate, (cyanide of silver,) insoluble in cold but soluble in boiling nitric acid. If this precipitate be well dried and heated, cyanogen gas will be given off, which may be known by its burning with a purplish flame. This test is very delicate.

3. _The Iron Test._-Of the liquid collected in the receiver above-mentioned, or the suspected acid liquid, saturated with a few drops of caustic pota.s.s, a portion is to be taken, and to this is to be added a small quant.i.ty of a solution of sulphate of iron. A dirty brownish or greenish precipitate will fall, consisting of a mixture of the oxide of iron and prussian blue. On adding a few drops of diluted sulphuric or hydrochloric acid, and thus dissolving the oxides, the prussian blue will immediately be made clear if hydrocyanic acid be present.

4. _The Copper Test._-Sulphate of copper added to prussic acid rendered slightly alkaline by pota.s.s, gives a greenish-white precipitate, which becomes white by the addition of a few drops of hydrochloric acid to dissolve the blue precipitated oxide of copper.

5. _The Sulphur Test._-One of the most useful tests for prussic acid, whether in the fluid or volatile state, is the so-called sulphur or Liebig's test. It is best adapted for detecting the acid in a state of vapor, and to this end a drop of yellow sulphide of ammonium in a watch-gla.s.s is held over the suspected liquid, which may be warmed by the hand to facilitate the evolution of the acid. In this position the watch-gla.s.s should be allowed to remain for some little time, after which a drop of solution of perchloride of iron is to be added, which will give rise to a blood-red color not discharged by corrosive sublimate.