Part 1

Transcriber’s Notes:

Text enclosed by underscores is in italics (_italics_).

Additional Transcriber’s Notes are at the end.

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INSOMNIA: ITS CAUSES AND CURE.

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INSOMNIA: ITS CAUSES AND CURE.

BY JAMES SAWYER, SENIOR CONSULTING PHYSICIAN TO THE QUEEN’S HOSPITAL, BIRMINGHAM.

Birmingham: CORNISH BROS., 1904.

PREFACE.

The following pages are the first two of the chapters of “Contributions to Practical Medicine,” as they stand in the fourth edition, 1904, of that book. They include my lectures on the causes and treatment of insomnia, in the necessarily colloquial style in which they were uttered. For the convenience of my professional brethren, these chapters now are offered to them in a separate form in this little book. Every word has been revised and many additions have been made, by the fruits of later experience, for the sake of clearness, completeness, and precision; this has been done with hope of usefulness in medical practice, and with the aim of accuracy in diagnosis and success in therapeutics.

31, TEMPLE ROW, BIRMINGHAM, 1904.

CONTENTS.

PAGE

I. THE CAUSES OF INSOMNIA.

The appetite of sleep.--The physiology of sleep.--Etiology of insomnia.--Symptoms of insomnia.--Intrinsic insomnia.--Varieties of intrinsic insomnia.--Psychic insomnia.--Emotional shock and prolonged mental strain as causes of insomnia.--The nervous temperament.--Symptoms of intrinsic insomnia.--Toxic insomnia.--Insomnia from tobacco.--Alcoholic insomnia.--Insomnia from tea or from coffee.--Gouty insomnia.--Senile insomnia. 9

II. THE CURE OF INSOMNIA.

No “rule of thumb” cure.--Hypnotic drugs.--Risks from hypnotics.--Causal treatment.--Bromide of potassium.--Cure of anæmia.--Alcohol.--Carminatives.--Adjuvant remedies.--Popular remedies.--Rhythmic sleep.--Physical exercise.--Sunshine.--Monotonous impressions.--Bedclothes.--Ventilation.--Food.--Cold.--Toxic insomnia.--Senile insomnia. 47

I. THE CAUSES OF INSOMNIA.[1]

_The appetite of sleep.--The Physiology of sleep.--Etiology of insomnia.--Symptomatic insomnia.--Intrinsic insomnia.--Varieties of intrinsic insomnia.--Psychic insomnia.--Emotional shock and prolonged mental strain as causes of insomnia.--The nervous temperament.--Symptoms of intrinsic insomnia.--Toxic insomnia.--Insomnia from tobacco.--Alcoholic insomnia.--Insomnia from tea or from coffee.--Gouty insomnia.--Senile insomnia._

The important subject of insomnia has engaged my attention for a long time. In 1878 I delivered a clinical lecture on the causes and cure of insomnia to the students of the Birmingham Medical School, in the Queen’s Hospital, and the matter of this discourse was afterwards further published in _The Lancet_, on June 15th and 22nd of that year. This lecture I revised and rewrote entirely afterwards, embodying in it some additions from my later experience in practice, and, so enlarged, it was included in each of the two editions, of 1886 and 1891, of my “Contributions to Practical Medicine.” In the autumn of the year 1900, I reviewed the subject again in two clinical lectures which I gave at my hospital, and these were issued in print in _The British Medical Journal_, on December 1st and 8th, 1900. These last lectures, in which I have tried to bring their subject up to a point at least abreast of our latest knowledge in the principles and practice of medicine, I have revised and rewritten; and I have amplified them, especially in their therapeutic parts. So rewrought, they form the contents of the following essay. This work, done as to the causes and cure of insomnia, that is, done as to particular diagnostic and therapeutic efforts in which the skill of the physician and the resources of our art are often taxed severely, in the intricacies of a difficult, delicate, and abstruse subject, I have tried to accomplish in the spirit of the Baconian philosophy, in the spirit of that aphorism of Bacon which Sydenham prefixed to his renowned “Tractatus de Podagra et Hydrope,” namely, “Non fingendum aut excogitandum, sed inveniendum, quid Natura faciat, aut ferat.” The result of my pleasant labours I venture now to offer to the judgment of my profession. My lectures on insomnia were delivered for the instruction of medical students in my clinical class; they are further published in these pages in the hope that they may help my medical readers in practice. In view of the conditions of the original delivery of these utterances, I have decided, in revising them, to preserve their colloquial style. Furthermore, in preparation for this present publication of these lectures, (1904,) I have revised them again, and made some additions to the therapeutics of my subject.

Sleep is a function of life, and life, in some sense, may be said to be a function of sleep, in man, in the animals which are a little lower than he is, in some sort in plants, in everything which lives. The living organism which cannot sleep cannot live. For all beings endowed with the crowning mercy of consciousness sleep is a pleasure as well as an appetite, and it is a necessity as well as both. For these conscious beings, strung as they are in their sentience to the most exquisite responses in the world’s vast chorus of living harmonies, sleep is indeed and in truth “tired nature’s sweet restorer.” For man, at the head of such beings, and perhaps the only of them which knows the cark of a mind’s unrepose, or the wear of “that unrest which men miscall delight,” sleep it is indeed which smoothes out life’s fretting creases and “knits up the ravelled sleeve of care.” That you may become practitioners of medicine you are students in this place of the manifold sciences of medicine in some of their chief practical bearings, mingled with the inexorable simplicities and with the endless intricacies of the art of healing. You are clinical students here of that cherished art of ours, an art which is of men philanthropic and of time perennial, as its lovely figure stands revealed in all its subtle and splendid details, firm and broad based upon the blended foundations of its great constituent sciences. You are students in this hospital I love of that great art of ours in clinical medicine, in its concrete application to individual cases of human suffering, no two of them indeed ever quite identical, no more than are identical a tree’s waving leaves or the billows of the rolling sea. Let us press forward together, in all the absorbing zest of the pursuit which is ours, to the brightest understanding which yet there may be of the intimate nature of sleep. Let us collect, discriminate and sort the causes which make for insomnia. Let us sift and sum up all which our sciences and our art, our experience, and even our empiricism, of which last I am not ashamed, have of tried adoption for its cure. In this work your physiological training, your clinical insight, your utilitarian aim, and even your poetic fancy and your literary culture, may all find coördinated play, in the comprehension and in the verbal depiction of functions and maladies which are intricate with our lives, associate with our highest attributes, and woven in woof and warp into the very texture of all our pains and of all our pleasures.

Favoured by your kind attention, I purpose to offer you some considerations upon the vital function of sleep, and upon the conditions, causes, and cure of insomnia, based upon a somewhat long and successful experience of those subjects in practice, as a physician. These subjects are certainly of first-rate importance in relation to our knowledge of the science and our practice of the art of medicine. Possibly you may scarcely be able to appreciate their relative importance while you are, as yet, only hospital students. Later in your careers, when you become engaged in actual practice among the sick, and especially when you take part in what is called private practice, often will you be confronted by the perplexities of insomnia, and often will your pleasant duty lie in successfully unravelling the causes of sleeplessness, on that soundest principle of causation and of therapeutics, _cessante causâ cessat et effectus_, and in curing insomnia by counteracting those causes, and by making their tiresome and diresome effects to cease. I hope to be able to show you that in such happy results the science and the art of the physician may play a successful part. Like thirst and like hunger, sleep is an appetite. We may define an appetite, in the words of the philosopher Bain, to be a craving produced by the recurring wants and necessities of our bodily or organic life.[2] An appetite, strictly so-called, has two characteristic marks, and these marks are strikingly characteristic of sleep; these marks are two conditions which are true to sleep--namely, its periodic recurrence and its organic necessity. We know that the natural course of a human life brings on sleep without the volition of the individual willing the event. The true character of sleep as a veritable appetite appears when it is resisted. Under such resistance the individual person experiences what is called, in metaphysical parlance, a “massive” form of uneasiness, discomfort, and pain. The will of the individual, in the presence of this uneasiness, is energetically urged to remove such discomfort and unrest, and is urged from pain towards pleasure, is urged to obtain the gratification of relief in what Bain called “the corresponding voluminous pleasure of falling asleep.”[3] In this imperatively urgent volitional impulse is the appetite of sleep. Sleep is a desire; with the further characteristics of its organic necessity, and its periodic recurrence, it ranks as one of our appetites.

The intimate physiology of sleep is a difficult subject, and the difficulties of its explanations have been the topics of much controversy, and such controversy appears to have issued from various combinations of the teachings of observation, of experiment, and of analogical and other reasoning, upon the phenomena of sleep. I do not propose to follow at length the details of this part of our subject. As a clinical teacher I must not overload your memories, but rather must I try to make easy your mental digestion. For our practical purposes I think we may understand that two distinct, but associated and related, vital changes occur in sleep. The one is some intrinsic change in those ultimate tissue elements of the brain which are concerned in consciousness; the other and “coarser” change is a diminished supply of blood to the brain, and especially to the blood vessels of the cortex of that organ. The former change is at present undemonstrable, excepting by inferential reasoning. Perhaps there is some essential and intrinsic change in the brain, and perhaps there also is some such change in the spinal cord and ganglionic nervous system, both of rhythmic occurrence, and both conditions of healthy sleep. Perhaps there is a functional depression of these parts in sleep, and especially of the cerebral cells, arising from “an accumulation in and around them,” as Sir Thomas Lauder Brunton puts the matter as to the cerebral cells in sleep, of some of the products of normal tissue waste. Perhaps for normal sleep an intrinsic change of this kind must gain the wide distribution I have mentioned. It is likely that there is in sleep a rhythmic change such as I have indicated, and that this change is sustained by the physiological effects of some of the issuants of those tissue changes, muscular and nervous, which especially occur in the active waking state of the body.

Perhaps for our sleep we must drown our cerebral cells in a kind of auto-intoxication with the ashes of our waking fires. We may usefully recall this view of the subject when we use exercise and fatigue as remedies for insomnia. The proof of the other broad change in sleep--namely, diminished blood supply to the brain, and especially to its cortex, rests on inference from physiological analogies, on various observations, and on the solid basis of direct experimental evidence. We must note, however, that the human brain, in its perceptive, cogitative, and volitional functions, in these great divisions of consciousness, is not the only part which sleeps. The whole living body sleeps. The changes which the event of sleep declares certainly extend beyond mere loss of consciousness; they extend to secretion, to the action of the heart and blood vessels in the general circulation of the blood, to respiration, to “reflexes,” and so extend to all the tissue modifications, and to all the other vital activities, upon which such manifold transitions depend. In order to complete your precognitions of the physiology of sleep, before we pass on to consider the several conditions of insomnia and their appropriate therapeutics, I may refer your attention to the admirable accounts of these subjects to be found in the text-books of Dr. Augustus Waller[4] and of Sir Michael Foster.[5] From each of these volumes I offer a brief quotation, which sufficiently illustrates our subject for my present purpose. On that part of his subject which is so important to us from a therapeutical standpoint--namely, the state of the cerebral circulation during sleep, Dr. Waller says:

“Although there is no doubt that in coma--a pathological state similar in some respects to physiological sleep--the cerebral vessels are congested, the observations of Durham on the exposed cerebrum of sleeping dogs, and of Jackson on the retinal vessels of sleeping infants, are to the effect that vessels shrink in sleep, and we may therefore feel reasonably assured that the sleeping brain, in common with other resting organs, receives less blood than in its state of activity. Moreover, Mosso’s investigations on exposed human brains afford evidence that the organ becomes more vascular during mental activity....”

That sleep concerns the whole body, and not the brain alone, is well put by Sir Michael Foster. He says:

“Though the phenomena of sleep are largely confined to the central nervous system, and especially to the cerebral hemispheres, the whole body shares in the condition. The pulse and breathing are slower; the intestine, the bladder, and other internal muscular mechanisms are more or less at rest, and the secreting organs are less active, some apparently being wholly quiescent; the secretion of mucus attending a nasal catarrh is largely diminished during slumber, and the sleeper on waking rubs his eyes to bring back to his conjunctiva the needed moisture. The output of carbonic acid, and the intake of oxygen, especially the former, is lessened; the urine is less abundant, and the urea falls. Indeed, the whole metabolism and the dependent temperature of the body are lowered; but we cannot say at present how far these are the indirect results of the condition of the nervous system, or how far they indicate a partial slumbering of the several tissues.”

You may find an interesting and instructive employment if you follow Sir Michael Foster through his discussion of the exact state of the body, and especially of the brain, in sleep. He points out, what is now generally accepted, that an alteration of the cerebral circulation is not the whole of sleep. He judges that “the essence of the condition is rather to be sought in purely molecular changes,” and then he goes on to suggest a resemblance between the systole and diastole of the heart and the sleeping and waking of the brain; and then he dwells on the various periodicities which may be observed in the activities of the human body, and even suggests that the fundamental rhythm of the heart may be a reflection of the mysterious cycles of the universe, while it may yet be only the result of the inherent vibrations of the molecules of its own proper structure.

If we exclude from our consideration the insomnia which is a concomitant of some forms of unsoundness of mind, and which kind of insomnia I do not propose to deal with in these lectures, you will find that absent or imperfect sleep, inability to sleep at all, or at a convenient time, or long enough, without the aid of drugs, is a frequent consequence or complication of numerous and varied conditions of disease. Etiology, as you know, is that division of the science of medicine which has to do with the causes of disease. The etiology of insomnia embraces the enumeration of all the causes of the malady. These causes are numerous, and a classification of the varieties of insomnia, upon the basis of their causal distinctions, is somewhat difficult. Let me recommend to you, for use in practice, the following classification of the varieties of sleeplessness under our consideration. It is the best etiological arrangement I can form, of the causal intricacies of our subject. It is a classification which you will find of service clinically, when you pursue the discovery of the particular causation of any given case of sleeplessness. Cases of insomnia seem to divide themselves naturally into two groups, namely, of cases of what may be called _symptomatic insomnia_, and of cases of what may be called _intrinsic insomnia_. Symptomatic insomnia attends a vast variety of morbid states, and is secondary to them, or is part of them. Intrinsic insomnia, as we shall see later on, is capable of distinct definition, and it breaks up naturally and simply into three smaller divisions, upon a causal principle of division.

As to symptomatic insomnia, pain, if severe enough, and from whatever cause arising; pyrexial elevation of temperature; frequent coughing, such as often occurs in pulmonary consumption; dyspnœa, such, for instance, as results from obstructive dilatation of the cardiac cavities, and appears to require an extraordinary vigilance of the nervous centres for the maintenance of the vital processes of respiration and circulation--are clinical conditions of disease which may prevent, shorten, or break up sleep. Such conditions are frequently met with in medical practice, as single causes of insomnia, or as conjoint causes of it in various combinations. In such and in similar instances the cause of the sleeplessness is obvious, and the consequential character of the insomnia--that is, its dependence upon a distinct and sufficient cause--is clear. For the therapeutic control of this kind of insomnia we may employ with success one of two curative methods, or we may employ a judicious combination of these methods, such combination being founded upon a skilled appreciation of the especial needs of each individual case. We may control sleeplessness of the kind in question either by the exhibition of remedies which directly cause sleep, that is to say, by the administration of some of the drugs which we know as hypnotics or soporifics, or we may control it by the employment of measures which combat the cause of the insomnia, by removing pain, by reducing the heat of fever, by quelling cough, by relieving cardiac disturbance and dyspnœal discomfort, and so on; or by using in conjunction hypnotics and remedies addressed to the removal of the cause of the sleeplessness. In such cases of symptomatic insomnia, as in medical practice generally, you will find that it is convenient to your duties, and that it tends to the thoroughness of your ministrations, if you regard the therapeutic indications of each case from the well-known standpoints, respectively, of the _indicatio causalis_, of the _indicatio morbi_, and of the _indicatio symptomatica_. By a judicious combination of the remedies so suggested you will be able to deal successfully with cases of symptomatic insomnia. By regarding the cause of the illness with which you have to deal as a medical attendant, by regarding the various pathological processes which underlie the progress of that illness, and by regarding the symptoms of that illness, by regarding these points in turn, or together, or in various combinations, with a judicious therapeutic intention, you may arrange your remedial efforts upon a systematic and comprehensive basis.

Now let us consider the details of intrinsic insomnia. There is a simple inability to sleep, which you will often be required to cure--a kind of insomnia which may be called for the sake of simplicity, but perhaps scarcely with strict truth, _insomnia per se_. This is a kind of wakefulness for which we cannot discover an objective or obvious physical cause; it is a kind of wakefulness which seems to depend upon an inability of the brain and nervous system generally to adapt themselves to the conditions which are necessary for sleep. We meet with this disorder more in private than in hospital practice. It occurs mostly in persons who are members of what are known as the upper and upper middle classes. It occurs mostly in persons of high mental endowment and of neurotic temperament. The malady is of extreme importance, and, happily, if its causes be understood and judiciously corrected and controlled, there are few affections which are more within the sphere of curative therapeutics. I think I can succeed in showing you how to unravel the complex causes and discover the successful treatment of this kind of insomnia.

The causes and the course of particular instances of intrinsic insomnia present some striking differences. You must know these differences, and be ready to recognise them, for the knowledge of them clears up alike the therapeutics, the successful treatment, and the prognosis of individual cases of the malady. I have found it to be convenient in practice to arrange the different clinical varieties of such insomnia into groups, in which the cause of the affection is the principle of division. These groups I call respectively the _psychic_, the _toxic_, and the _senile_. Let us see how these divisions work out in detail.

The brain in natural sleep is, as we have seen, relatively anæmic. The cerebral arteries, as we have seen, are more filled with blood than during sleep, when the brain is in full waking and working activity. When thought is active, the parts of the brain concerned are living relatively rapidly; they are actively receiving nourishment from the blood, and they are, too, actively ridding themselves of the waste products of their vitality. In sound natural sleep the brain is inactive, excepting those parts of it which are concerned in the processes of organic life. In sleep the blood flows to and through the brain in streams which are smaller and gentler than in the waking state. The cells concerned in thought, volition, and feeling are not expending energy, they are renewing it and storing it--they are resting. Any cause, however little we may be able to trace the details of its operation, which directly prevents a repose duly deep of a sufficient number of those brain cells which are the organs of conscious thought, will render sleep impossible; relative cerebral hyperæmia is an inseparable consequence of such activity, and such relative cerebral hyperæmia becomes a concurrent, but subordinate, cause of insomnia. Here there is progression through a vicious circle of two terms, in which the impulse of the morbid movement springs from the cerebral cells. So we see that there are causes of insomnia which we may fairly regard as acting primarily in sustaining cerebral activity, and with it, and in consequence of it, relative cerebral hyperæmia, which hyperæmia becomes a contributory cause of the cells keeping awake.

In some other cases of intrinsic insomnia I think we may regard the malady as arising primarily in a perversion of the cerebral blood supply. Any cause which prevents the brain from becoming relatively anæmic in a sufficient degree for sleep will produce sleeplessness. Any ingested agent which sustains cerebral hyperæmia, or any pathological change which impairs sufficiently the contractility of the smaller cerebral arteries, may prevent wholly, or in part, the occurrence of such a degree and extent of cerebral anæmia as is required for the production of sleep, and without which sleep cannot be.