ON INSOLATION.

In our April number we published the commencement of a

paper, (to be continued hereafter,*) by Surgeon Barnard, on the " Pathology and Treatment of Coup-de-soleil or Insolatio and

the subject has likewise come under discussion, at a meeting of

the " Bengal Branch of the British Medical Association," in

Calcutta.

The profession is under considerable obligation to Mr.

Barnard for drawing attention to a mode of treatment, in heat

asphyxia, which, we believe, has not, in that disorder, been adopt- ed to the extent that it, perhaps, might have been : although we venture to think that the amount of success which the author

predicts for it is hardly to be anticipated, viz., recovery in nine cases out of ten. Mr. Barnard speaks of the condition, which

he would treat in this way, under the synonymous terms " coup-

de-soleil" or *' insolatio but we take leave to designate it

under, what we conceive to be, the more appropriate head of

heat asphyxia. The treatment of a disease should always, where possible,

be based upon its pathology ; and, although different causes

may lead to the same results, requiring much the same treatment in the main, it is absolutely necessary that we should separata these causes clearly in our minds, as a due consideration of each

may lead to more correct notions of their individual patho-

logy. Asphyxia, for example, is a condition which may be

produced in several ways : the lungs may become engorged from cobra, or like, poisoning ; from drowning ; under the influ-

ence of heat alone ; or of heat plus drink or a vitiated atmos-

phere, &c., &c. It may be good practice to keep up artificial

respiration in each of these cases, but, with reference to the agent which, immediately or remotely, has produced the asphyxiated

condition, something more may be required, too. If it be a

case of ardent fever, quinine in large doses may be absolutely called for. It strikes us that Mr. Barnard lays too much stress

upon artificial respiration, per se. Were it not that we satisfied

ourselves, at the discussion which took place at the meeting of the

Medical Society, that the author of the paper quite intended to

include, in his category, what is sometimes spoken of as

"ardent fever" synonymously with insolation, , we should

have inferred, from a perusal of his paper, that he had not so

intended ; for, in none of the cases cited by him is the character-

istic feature?the pathognomic sign of the disease?viz.,

pungent lieat of the skin, once mentioned. We are to understand,

then, that artificial respiration would be the remedy on which

Mr. Barnard would most rely in ardent fever, as much as he

would in pure ictus solis, coup-de-soleil, or sunstroke, where

the individual had been simply struck down, his nervous system

prostrated under the influence of the shock, but where thert

was no pungency of skin.

This brings us to the question?What is insolation ? We

* We have reviewed Mr. Barnard's paper, without waiting for his final

communication, which, we understood, doea not affect the text.

joq THE INDIAN MEDICAL G-AZETTE. [June 1, 1868.

have always been led to believe that it was sun, or heat stroke ;

and something more.

It so happened that, at the meeting referred to, a medica^

officer, who ha3 recently gone through the course at Netley, stated that he had never, when there, heard any other

cause assigned for insolation than mere heat : and an opinion, generally, was expressed at the same meeting, that heat alone,

excepting, perhaps, the occasional complication of liquor or

opium, was the cause of it. Now it may be well to invite

the attention of the profession throughout India to this

important question,' as, a few years ago, when insolation was

investigated for the first time more deeply than in times gone by, and a more rational plan of treatment was laid down than

venesection, and the antiphlogistic regimen, there were some who thought that insolation, with its pungent skin, (ardent* fever), was the result of something in addition to heat. Heat,

in their estimation, was simply the exciting cause. We have

not space to enquire into the arguments for and against this

opinion, but we would invite those who are willing to pursue the enquiry during thef coming hot season, when, unhappily, such cases maybe expected, to consult the following authorities

in the pages of the Indian Annals:?fa) October, 1855, No. V, Marcus G. Hill, on Insolation or Heat Apoplexy, fbj July 1859, No. XII, Deputy Inspector-General T. Longmore, on some

Tabulated Cases of Ileat Apoplexy, (c) Report on the Outbreak

of Insolation in the 3rd Cavalry, by Surgeon T. II. Butler,

(d) October, 1856, No. VII, on Indian Fevers, by J. B. Scriven,

Exq (ej No. XX, August, 1866, an Enquiry into the truth of the

Opinions generally entertained regarding Malaria, by W. J.Moore,

Surgeon, Marivar Political Agency. This author quotes Dr. N.

Chevers as having remarked on the probability of sudden

attacks of heat apoplexy being caused by malaria in a concen- trated form ; with various others.

It will be seen, on reference to these authorities, that the

idea of malaria being the remote cause of insolation, or ardent

fever, rests upon very insufficient grounds. Or, rather* it is by no means established that this is the origin. Still, there is ample evidence to lead to the belief that there is something more than

mere heat in the fons et origo mali. To quote from Mr. Barnard's

own favorite authority?Sir Thomas Watson. Sir Thomas does

indeed give one instance, that of the rabbit in Sir Benjamin Brodie's experiment, where death took place apparently as

the result of mere heat. But in this case there was no portal

open for the relief of the heated blood ; there was no perspira- tion. The animal died, therefore, from the prostrating effect

of the accumulated heat. So that, free perspiration being essential to enable human beings to remain in ovens heated to

a temperature sufficient to boil or roast an egg, as in the

instances quoted by Mr. Barnard from Sir T. Watson's

book, this case of the rabbit does not invalidate the proposition that something more than mere heat is required to produce a

* The term " ardent fever" should not, it is urged by some authorities, bo used synonymously with insolation. But, as in consequence of heat, which is caused directly or indirectly by the sun, there is fever, and as

this is of a very ardent description, the application of the term appears to us to be very appropriate. We should fear that a discontinuance of its use in this way, would lead to incorrect notions of its pathology.?Ed., I. IT. G. t This invitation is hardly applicable now. The article was written for the

last number of the Gazette, but postponed to give place to more pressing matter.?Ed., I. 21. G,

fatal result. Doubtless, in debilitated constitutions, where there is great loss of nervous energy?the effect of excesses or disease??

heat alone will strike down and kill, without any other cause whatever being in operation, and the more readily where the

skin is dry, and there are no means of relief open. But it is

to insolation or ardent fever that we would especially apply our remarks. It is remarked by-those who maintain that heat alone will produce it, and who ignore malaria, that cases of insolation do not occur at what is considered the malarious seaon of the

year, viz., the autumn. This, as a rule, is true, though there

are exceptions. But cholera and insolation often go together, and the former is undoubtedly associated with a poisoned state

of the atmosphere. When Sir Thomas Watson wrote his

lectures, insolation was less understood than it is now. Sir

Thomas Watson himself uses the term, and after him Mr. Barnard

synonymously with mere sunstroke. For its deeper meaning we are indebted to Dr. Scriven, whose classification of Indian fevers is simple, yet thoroughly practical, whilst it is eminently, we believe, true.

Whilst then we thank Mr. Barnard for laying stress upon a

remedy, (in cases of heat asphyxia, however produced,) which

may not have had hitherto a sufficient trial, we would wish to

urge the younger members of the profession, of those who

are practically unacquainted with tropical disease, not to draw too hasty an inference from his paper, that insolation (the ardent fever of Dr. Scriven) is mere sunstroke, and that artificial

respiration is tlie one remedy upon which reliance is chiefly to

be placed. Mr. Barnard advocates, it is true, the cold douche

for reducing the temperature, which, he believes, is the cause of

the temporary paralysis of the cerebro-spinal ganglia connected

with respiration (though in his paper, singularly enough,

pungency of skin is omitted ;?indeed, from the description of

his cases, one would think that they were the result of simple shock to the system from excessive heat, cases of mere ictus

solis, in short*): at the same time, (our author must pardon us if

we are in error,) it would appear that this remedy, upon which, in conjunction with stimulants, we have been most accustomed

to rely, is put somewhat in the background. In the single case which came under Mr. Barnard's observation, he does not

appear to have used the cold douche at all.

We commend the study of insolation, or ardent fever, to the

careful consideration of the junior members of the profession. We are not yet sufficiently enlightened on the action of malarious,

any more than of other, poisons, to be able to say, with preci- sion, that malaria has nothing to do with the production of certain diseases. Our chief object, in penning these remarks, is to invite further enquiry, as to whether malaria or a poisoned atmosphere, plus heat, has any share in causing insolation, or ardent fever ; and we shall be only too glad to chronicle

carefully recorded cases in the columns of the Gazette.

* Though the author says, "you never get any form of insolation without heat," he does not mention its existence in the cases which lie gives us.