Possible Therapeutic Value of These Experiments.
It at once suggests itself to the physician that some clinical use
might be made of the facts outlined above. If such striking results can
be obtained in a rabbit it is possible that some modifications of the
use of these saline purgatives might be made in the human being.
If in the first place it is found that subcutaneous or intravenous
injections of saline purgatives are effective in man, there arise in
both medical and surgical practice occasions in which these methods
of administration would be of the greatest advantage. It is to be
remembered in this connection that the administration by these methods
of MgSO_{4} is especially dangerous. This salt when rapidly absorbed
seems to be very poisonous. Rabbits frequently die in a few minutes
after an intravenous injection of a quantity relatively small as
compared with the amount of Na_{2}SO_{4} which can be given in this
way. Barium chloride is extremely active as a subcutaneous purgative,
but should be used with the greatest caution and in very minute
quantities on account of its very poisonous character. I can give no
idea of the dose that might be given to a human being without danger. A
rabbit usually does not recover from a subcutaneous injection of 3 c.c.
m/8 BaCl solution.
The fact that saline purgative solutions applied to the peritoneal
surfaces of the intestine act very rapidly may suggest some use in
abdominal surgery for this method. If it were desirable to have
evacuation of the bowel rapidly follow an abdominal operation this
procedure might be resorted to. An isotonic solution (m/6) of sodium
sulphate or sodium citrate would be most favorable for this purpose.
The possible uses to which our knowledge of the action of calcium
may be put has aroused some discussion. The fact that it suppresses
muscular and nervous irritability (Loeb), and as shown in the
experiments above, inhibits the muscular and glandular activity of
the intestine, as well as the secretory activity of the kidney, makes
it seem probable that some practical use may be made of it in certain
conditions in the human being. The most important of these conditions
is perhaps the persistent diarrhœa which sometimes accompanies
disorders of an hysterical or neurasthenic sort. There have already
come under my notice several cases of diarrhœa of nervous origin which
were quite uncontrolled by morphine preparations. These cases were
apparently entirely relieved by calcium chloride given for only a few
days. (grs XX t.i.d.) Whether a large number of similar patients will
show the same results remains to be seen. The treatment is evidently
to be applied to only a small class of patients, roughly those cases
of persistent diarrhœa of apparently nervous origin, which cannot be
influenced by opiates.
When rectal infusions of NaCl are not retained it is possible by adding
CaCl_{2} to the solution to stop the movements of the rectum which
cause their expulsion. Enemata of NaCl containing CaCl_{2} are retained
much better than those of pure NaCl.
The marked action of calcium on the kidney suggests that certain
conditions might arise where it could be made use of. In nervous
polyuria it can be given with benefit; and although we know practically
nothing as to the etiology of diabetes insipidus, it is possible that
calcium might be employed with advantage to stop the abnormal flow of
urine.
With regard to general conditions such as the muscular and nervous
irritability accompanying hysterical and neuraesthenic disturbances
little can be said as to the possible value of calcium. Loeb drew
attention to the possibilities of its being of use in these diseases,
but there is not sufficient evidence to make any statement concerning
it. The extreme irritability which is present in some types of insanity
might also be tested in this respect.
Calcium might also be of benefit in asthma where the two distressing
symptoms are spasmodic contractions of the bronchioles and a
hypersecretion from the mucous membrane of the larger and smaller
bronchi. Judging by analogy from the experiments described above,
calcium should not only relieve the muscular contractions but also
inhibit the secretion.
These suggestions are made simply in the hope of stimulating clinical
research in this direction.
Wright has recently stated that calcium relieves urticaria, a
circumstance which he refers to the influence of calcium on the
coagulability of the blood, which he says is diminished in this
condition. It seems more probable from the above experiments that the
calcium inhibits the secretion or passage of fluid from the lymph
vessels to form the vesicles.