Externally applied and allowed to evaporate, chloroform causes a sense of coldness and depresses the terminations of the sensory nerves, acting as an anodyne and producing insensibility to pain. If evaporation is prevented it irritates, reddens, and blisters the skin. These effects are followed by anaesthesia of the part. Given by mouth, chloroform has a hot, sweet taste, and in the stomach produces a feeling of warmth. In large quantities or undiluted it causes violent gastroenteritis. Medicinally it is given as an antispasmodic, anodyne, and carminative. It enters the circulation through the lungs, stomach, and unbroken skin. It reaches the tissues very rapidly, and exerts its greatest power on the central nervous system. It is excreted partly as chloroform by the kidneys, lungs, mammary glands, and skin, and part is lost in the system.
In poisoning by chloroform taken internally the symptoms are: stupor; cold skin covered with perspiration; pulse slow, thready, sometimes almost imperceptible; respirations at first stertorous, afterwards becoming shallow, irregular, and infrequent. The symptoms come on almost immediately after it has been swallowed, and death may result in a few hours, or may result after a longer time from gastro-enteritis or from inflammation of the trachea.
There is no antidote for chloroform, on account of its extremely rapid diffusibility through the system. The stomach must be emptied, washed out, if necessary, and cold-water affusions applied to the head, and plenty of fresh air admitted. Artificial respiration should be practised steadily and unremittingly.
The smallest fatal dose recorded is ʒ ii.
Average dose, ℥ SS.-15 mils.
Composed of soap liniment and chloroform.
In the use of the vapor of chloroform as an anaesthetic there are three stages of narcosis: the first, a short period of excitement during which the sensibilities are blunted, though consciousness is not lost; second, the stage of anaesthesia. Consciousness and sensibility are abolished; the pulse is about normal in frequency and slightly weaker; respiration slow, heavy, and stertorous. During this period operations are performed. The third stage is a dangerous one, with profound narcosis; entire muscular relaxation; stertorous breathing, gradually becoming sighing and weak; and complete abolition of reflex actions.
Chloroform is preferred to ether in some cases because it is easier and pleasanter to take; is more prompt in its action; is not so nauseating, and its after-effects pass away more quickly. In obstetrical cases it is preferred because by its use a stage of insensibility to pain can be produced without bringing on complete muscular relaxation, which would delay labor.
No fatal cases are known to have occurred in parturient women, although in surgical cases death has occurred quite frequently and with great suddenness, from paralysis of the respirations and heart, and ordinarily chloroform is considered much less safe than ether. In giving chloroform to a patient in labor (which a nurse may be required to do), the face must first be oiled with vaseline to prevent any possibility of blistering.
About 3 ss. of chloroform is poured at one time on a sponge, or piece of lint, and held before the nose in a way that will allow plenty of air to mix with it, as the chloroform should only be in a strength of 3 per cent. with the inspired air when inhaled.
It is only to be inhaled during the existence of a pain, and not in sufficient quantity to lessen uterine contraction. If the pulse weakens, the respirations grow shallow, or the pains become insufficient, it is stopped.
It is well to keep the supply safely out of reach in the case of excitable and hysterical patients.
In the treatment of poisoning by inhalation of chloroform vapor, the head is lowered to an angle of about 40°. Plenty of fresh air is needed, and should be warm, about 80°-85° F. External heat must be applied, and artificial respiration kept up for several hours.