Copyright
Leonard Erskine Hill.

Caisson sickness, and the physiology of work in compressed air online

. (page 1 of 22)
Online LibraryLeonard Erskine HillCaisson sickness, and the physiology of work in compressed air → online text (page 1 of 22)
Font size
QR-code for this ebook


BIOLOGY LIBRARY



LOG



CAISSON SICKNESS



INTERNATIONAL MEDICAL MONOGRAPHS

_ ,..,.. f Leonard Hii.i., M.B., F.R.S.

General Edliors \mi.uAM Bulloch, M.D.

THE VOLUMES ALREADY PUBLISHED OR IN
PREPARA I ION ARE:

THE MECHANICAL FACTORS OF DIGESTION. By
Walter B C , V.M., M.D., George Higginson Professor

ofTl. Harvard University. [Ready.

SYPHILIS: FROM THE MODERN STANDPOINT. By
Macintosh, M.D., Grocers' Research Scholar; and Paul
1 :i [)es, M.D., B.C , Assistant Bacteriologist to the London Hos-
pital. [Ready.

BLOOD-VESSEL SURGERY AND ITS APPLICATIONS.
By Charles Claude Guthrie, M.I>., Ph.D., Professor of
Physiology and Pharmacology, University of Pittsburgh, etc.

[Ready.

CAISSON SIKCNESS AND THE PHYSIOLOGY OF WORK

in Compressed Air. By Leonard Hill, M.B., F.R.S., Lecturer
on Physiology, London Hospital. [Ready.

The following arc in Preparation:

LEAD POISONING AND LEAD ABSORPTION. I

. Legge, M.D, D.P.H., H.M. Medical In pect >r of Fac-
tories, etc. ; and Kenneth W. Goadby, D.P.H., Pathologist and
Lecturer on Bacteriology, National Denial Hospital

THE PROTEIN ELEMENT IN NUTRITION. By Major

I P. M i iv, M.B., lUli., B.A.O., M.R.C.P., I.M S., Professor of
Physiology, Medical College, Calcutta, etc.

SHOCK : The Pathological Physiology of Some Modes of
Dying. P.y Yandeli Henderson, Ph.D., Professor of Physiology,
Vale University

THE CARRIER PROBLEM IN INFECTIOUS DISEASE.
Ky I. C. Ledingham, D.Sc, M.B., M. A., Chief Bacteriologist,
Lister Institute ol Preventive Medicine, London ; and J. A. Ark-
it, M V. M.D., M.R.C.P., Lister Institute of Preventive
ndon-

/ />. st i iptive < 'in ular o/ilu

application to tlic Pub.::.

LONDON EDWARD ARNOLD

\ i ■ i .i



INTERNATIONAL MEDICAL MONOGRAPHS

_ . _ ... ( Leonard Hill, M.B., F.R.S.

General haitors < ... „ ' T .

I William Bulloch, M.D.



CAISSON SICKNESS

AND THE PHYSIOLOGY OF WORK
IN COMPRESSED AIR



BY

LEONARD HILL, M.B., F.R.S.



LONDON

EDWARD ARNOLD

NEW YORK : LONGMANS, GREEN & CO.

1912

[All rights reserved]



GENERAL EDITORS' PREFACE

The Editors hope to issue in this series of International Medical
Monographs contributions to the domain of the Medical Sciences
on subjects of immediate interest, made by first-hand authorities
who have been engaged in extending the confines of knowledge.
Readers who seek to follow the rapid progress made in some new
phase of investigation will find herein accurate information acquired
from the consultation of the leading authorities of Europe and
America, and illuminated by the researches and considered opinions
of the authors.

Amidst the press and rush of modern research, and the multitude
of papers published in many tongues, it is necessary to find men
of ripe experience, who will winnow the wheat from the chaff, and
give us the present knowledge of their own subjects in a duly
balanced, concise, and accurate form.

The present volume is the work of one of the Editors, who

hopes that the results of his prolonged investigation bearing upon

Caisson Sickness will be found of sufficient interest to justify

inclusion in the Series.

WILLIAM BULLOCH,
LEONARD HILL.
February, 1912.



241319



PREFACE

In this volume I have gathered together the results of some
fifteen years' research into the causation, cure, and prevention
of compressed-air illness — a subject of the greatest importance
to engineers who build harbours, sink the piles of bridges, and
tunnel under the rivers of the great cities of the world by means
of compressed-air caissons ; also to the navies and mercantile
marines, and the pearl and sponge fisheries, which employ divers.
The limits of many vast commercial undertakings are set by the
toll of life which work in compressed air has hitherto demanded.
By the exact methods of scientific investigation and control, work
hitherto dangerous can be made safe, and the limits hitherto set
to the work extended. In the pearl fisheries off North-West
Australia 7 per cent, of the divers lose their lives. They are
poor Japanese, ignorant, uncontrolled by scientific method, and
periodically tempted to try the rich, untouched banks where
shell lies at depths of 20 to 25 fathoms, are frightened back to
the shallower, fished-out banks by those dreadful cases of
paralysis and death which occur among them.

By a properly selected, trained, and equipped band of divers
these beds undoubtedly could be fished with safety, and at a
great commercial profit. So, too, the engineer could carry out
important works at a pressure which he has not hitherto dared
to use.

In compiling this book I have drawn largely on the masterly
pioneer work of Paul Bert, " La Pression Barometrique " — a
book which has suffered an amazing neglect by English and



VI U PREFACE

American engineers and the medical officers employed by them
in compressed-air works.

The two big volumes, "Luftdruck Erkrankungen," by
R. Heller, \V. Mager, and H. von Schrotter, have been a mine
of wealth to quarry in, containing as they do a complete
analysis of the literature of my subject up to the year 1900.

Von Schrotter has since brought the subject up to date by
further summaries published in the Hygienisches Zentralblatt,
Bd. III., 1907, and "La Travail dans l'Air Comprime,"
Bruxelles, 1910.

The Report of the Admiralty Committee on Deep-Sea Diving
(1905) contains the important contributions of John Haldane to
this subject, and forms the basis of my discussion of the method
of stage decompression which has been introduced into Admiralty
practice.

The mathematical calculations on which the Admiralty table
of stage decompression is founded have never been published,
and so cannot be critically examined. The table is built very
Largely on theoretical data concerning the circulation of the
blood, which cannot be regarded as fixed in the varying states
of activity of a man's body.

There is no doubt that the periods of decompression can be
greatly shortened by the taking of active exercise during decom-
pression, so as to accelerate the circulation, the ventilation of
the lungs, and the escape of the dissolved nitrogen out of the
bodv. The engineer considers the long periods fixed by the
Admiralty Committee unpractical. He can safely shorten them
if he trains his men to exercise themselves during decompression.
I bring evidence to show that the breathing of oxygen at a
certain stage in the decompression is of most potent
assistance. The London County Council has spent large sums
in excessive and, I think, useless ventilation of Thames Tunnel
caissons, for carbonic acid has nothing to do with the causation
of Caisson Sickness. The money would have been better spent
on cooling the working chambers.



PREFACE !X

Compressed-air work has its humorous side. Two workers in
the Tower Bridge caissons were seized with " bends." One danced
about with the pain, and he was quickly relieved ; the other
knelt down and prayed. As the religious exercise proved of no
avail, he also quickly betook himself to dancing and found relief.

There is the story, too, of the Town Councillors who went
to celebrate the completion of a section of certain tunnel works,
and took some champagne into the caisson. On drawing the
cork the champagne proved flat, and, thinking it bad, they drank
none, all except one, who tasting liked the wine, and drank half
the bottle, which he then corked and put in his pocket. During
decompression in the air-lock the cork blew out with a loud
report, and there was a great commotion, as one Councillor
asserted he had been shot. This was nothing to the commotion
made by the other who had drunk when the champagne effer-
vesced in his stomach.

I am greatly indebted to all who have worked with me on this
subject, in particular Prof. J. J. R. Macleod, Mr. Major Green-
wood, and Mr. F. J. Twort. Dr. Paul Fildes, Dr. C. Ham, Mr.
R. A. Rowlands, and Mr. H. B.Walker, have also given much help.
Mr. E. W. Moir has given me the results of his great experience
of Recompression. Mr. E. Tabor has very kindly given me a
diagram of the shield employed in the L.C.C. Greenwich Tunnel.
Mr. R. H. Davis, of Messrs. Siebe, Gorman and Co., has afforded
me the greatest assistance, in giving me valuable apparatus,
material, and his experience in the course of the researches,
and in lending me blocks of figures of the apparatus used to
illustrate this book. The firm of Siebe, Gorman and Co. has
shown a most enlightened interest in the value of scientific re-
search. Dr. Martin Flack has been kind enough to read the proofs.

There is much yet to be done, but I hope this book may be of
some little use in furthering the safer use of compressed air.

LEONARD HILL.

LOUGHTON,

January 12, 1912.



CONTENTS

CHAPTER PAGE

I. THE NAKED DIVER - 1

II. THE EVOLUTION OF THE DIVING DRESS AND BELL - - 17

III. THE CONSTRUCTION OF THE DIVING APPARATUS AND ITS USE - 37

IV. THE NATURE OF CAISSON SICKNESS - 56

v. the nature of caisson sickness — continued - - 74

vi. lesions of the spinal cord - - - - 93

VII. theories as to the cause of compressed-air illness - 99

VIII. physiological effects of compressed air - - - 118

IX. effect on respiratory exchange and oxygen-poisoning - 127

X. THE BODY TEMPERATURE AND VENTILATION OF CAISSONS

NITROGENOUS METABOLISM - - - 146

XI. THE RELATION OF AGE, BODY WEIGHT, AND FATNESS TO CAISSON

ILLNESS - - 164

XII. EFFECTS ON THE BLOOD - - 178

XIII. THE THEORY AND PRACTICE OF DECOMPRESSION - 196

XIV. THE THEORY AND PRACTICE OF DECOMPRESSION — continued 216
XV. TREATMENT OF CAISSON SICKNESS — RECOMPRESSION - - 237

INDEX - - - 251



CAISSON SICKNESS

AND THE

PHYSIOLOGY OF WORK IN COMPRESSED AIR

CHAPTER I

THE NAKED DIVER

While some explore the confines of the air, others no less ven-
turesome seek the world which lies beneath the waters, and in
the curious gear of the diver creep with the crabs through the
marvellous scenery of the sea. By means of compressed air
man has kept out the waters, and built and tunnelled in dry-
ness under the rivers of the great cities of the world. By the
breathing of oxygen he has attained in a balloon to an altitude
that tops the Himalayas by a mile ; on the other hand,
he has never attained to, and probably never will attain to,
the bottom of the sea, in the greatest depths of which there
is a superincumbent pressure of some five miles of water, or
800 atmospheres.

It is rash to say that anything is impossible, but physical
and physiological knowledge alike point to the impossibility of
man ever translating his body beyond the atmosphere of the
earth, or down to the bottom of the ocean. The only way by
which he could reach the abysm of the sea would be by her-
metically sealing himself in a metal ball, strong enough to stand
the compressive force of 1,000 atmospheres. He would be
none the wiser if so enclosed he were lowered as a plummet to
the bottom.

It is to the physiologic conditions of the diver and the worker
in compressed air that this volume is devoted.

1



CAISSON SICKNESS



The Naked Diver.

From the earliest time naked divers have carried on the pro-
fession of sponge and pearl fishers, notably in the Mediterranean
Sponge Fisheries and the Ceylon Pearl Fisheries. Spanish
writers of the sixteenth century speak of the extensive employ-
ment of divers in the Gulf of Mexico, and mention the bleeding
from mouth and nose and ears from which the divers suffered.
It was not until 18:57 that Siebe perfected his closed diving

dress, and several years elapsed
before it was introduced into
the pearl and sponge fisheries.

Denayrouze brought the di-
ving dress into use in the
Grecian Archipelago some forty
years ago, and even now so
large is the population de-
pendent on those engaged in
the fisheries that regulations
have been made both in Ceylon
and Turkey restricting the use
of diving dresses within the
three-mile limit.

The naked diver is trained
from childhood to his trade.
Mothers are said to hold their
children under water to practise
their powers of endurance. In
the island of Ashima (Province
of Idsu), in Japan, it was customary for the women to dive for the
shell Awabi. The women ruled the men, who stayed at home
and minded the baby. A distinguished Japanese artist tells me
that as a child he heard the origin of this custom lay in the fact
that the very cold water in the depths had a perishing effect on
the testicles of the men. It was reputed that the sea-bream
attacked the men and bit off their testicles, but it was really the
cold. The women, having no vital parts so exposed to cold, took
over the work, both for the men's sake and their own.

The naked divers go to astounding depths : GO to 70 feet is
quite a usual depth, but rarely, it is said, 120 to 130 feet is
attained. The depth it is possible t go t i- limited by the time




Fig. 1. — Japanese Women Divebs
(Utamako).



THE NAKED DIVER 3

it takes to get to the bottom and back. The divers shorten the
time of descent by grasping a heavy flat stone, or by putting the
feet in a stirrup attached to such a stone — in this case plunging
down feet foremost. A rope is attached to the stone, and the
diver either may be hauled up by the rope or ascend by his own
efforts. Some of the deep-water divers put a horn clip on their
nose, an oiled wad in their ears, and a small bit of oiled sponge
in the mouth.

The time that the divers are said to stay under water is often
greatly exaggerated. Robert Boyle writes thus : " Those that
dive for pearls in the West Indies are said to be able to stay a
whole hour under water ; and Cardan tells us of one Calamus,
a diver in Sicily, who was able to continue (if Cardan neither
mistake nor impose upon us) three or four times as long. Not
to mention, your Lordship, that you have yourself oftentimes
seen in England a corpulent man who is wont to descend to the
bottom of the Thames, and bring out of deep holes, at the bottom
of the banks, large fishes alive in his hands." Cardan, the mathe-
matician, unable to solve an equation, is reputed to have hired
a band of cut-throats to waylay, carry to a cave, and steal the
solution from a rival mathematician. He therefore would not
stop at a mere imposition. As to the truth of this and the use
of oiled sponges, Boyle says : "An ingenious man of my acquaint-
ance, who is very famous for the useful skill of drawing goods,
and even ordnance, out of sunk ships, being asked by me how
long he was able to continue at the depth of 50 to 60 feet under
water, without the use of respiration, confessed to me that he
cannot continue above two minutes of an hour without resorting
to the air, which he carries down with him in a certain engine
(whereof I can show your Lordship a description). Another
thing I also learned of him by inquiry, that was not despicable :
for, asking him whether he found any use of chewing little sponges,
dipped in oil, in his mouth, when he was perfectly under water,
and at a distance from his engine, he told me that by the help of
these sponges he could much longer support the want of his
wonted respiration than he was able to do without them. The
true cause of which would, perhaps, if discovered, teach us some-
thing pertinent to the problem touching the respiration of
fishes."

In regard to the respiration of fishes, it is difficult to see what
Boyle had in mind ; but as to the use of the oiled sponges



4 CAISSON SICKNESS

Edmund Halley also had something to say at a meeting of the
Royal Society in 1717, he then being secretary, and Sir Isaac
N i'wton president : *

" Considering how small a Quantity of Air can be supposed to
be contained in the Pores or Interstices of a Sponge, and how
much that little will be contracted by the Pressure of the in-
cumbent water, it cannot be believed that a supply by this
means can long subsist a Diver. Since by Experiment it is found
that a gallon of Air, included in a Bladder and a Pipe reciprocally
inspired and expired by the Lungs of a man, will become unfit for
any further Respiration in little more than one Minute of time ;
and though its Elasticity be but little altered, yet, in passing the
Lungs, it loses its vivifying Spirit, and is rendered effete. ... I
shall not go apart to show what it is the Air loses by being taken
into the Lungs, or what it communicates to the Blood by the
extreme ramifications of the Asperia Arteria." He recognizes
that there is no proof of any communication between these- — the
bronchial tubes, and veins and arteries.

The chewing of the sponge and swallowing of the oil probably
has an inhibitory effect on the respiratory centre. In a series of
experiments on the power to hold the breath, made by Martin
Flack and the writer, we have noted that swallowing movements
are generally made when the subject nears the breaking-point,
and wishes to extend the period of breath-holding to the utmost.
Although oil can hold in solution more than five times as much
oxygen and nitrogen as water (Vernon), the oiled sponges at
the most could only add a centimetre or two of oxygen to the
available supply, and the effect gained by chewing the sponge
cannot be attributed to this.

When the naked diver returns to the surface, he may either
rest three or four minutes and then dive again, or return to the
boat and let another take his place ; and the work thus proceeds
during the heat of the day. The warmth of the tropical sea
lenders this form of diving possible. Martin Flack and I have
found it more difficult to hold the breath with the face immersed
in iced than in warm water, for the discomfort of the cold adds
itself to the impulsion to breathe. The average for sixteen
experiments was forty-two and a half seconds for warm, and
t wenty-nine and a half seconds for cold, water.

The mos1 remarkable account of the exploits of naked divers
' Transactions of the Royal Society, xxix., 1717.



THE NAKED DIVER

in very cold water is cited by Heller, Mager, and von Schrotter,*
from a book of travels in the Northern Sahara, by Colemieu :

" The water-supply is obtained from artesian wells which are
up to 130 feet in depth. The ' eye ' of these wells often gets
stopped up with sand, brought up from below by the spring,
or blown in from above. The difficult and dangerous work of
cleaning the ' eye ' is carried out by a guild of divers. A single
diver brings up as much sand as he can in three to four minutes !
Not infrequently a diver loses his life over this work. The
descent and ascent are made by means of ropes which are let
down the well. The diver stops up his ears with wax, and, getting
into the water, waits a while to get used to the temperature. He
then gives the signal, fills his lungs as much as he can with a
couple of breaths, and sinks under. His comrades can follow his
movements by the two ropes which reach to the bottom. Three
minutes and two seconds have already gone by, and one is
beginning to get anxious, when he rises to the surface half
asphyxiated and almost unconscious. His comrades grip him
and hold him while he gets his breath, and then he climbs out
and goes and warms himself by the fire, while the next takes his
turn. The young men of the guild seem strong and healthy, the
old lean and straight-chested, but they stay under longer and
suffer less. The young men are too hasty, and that tells against
them. The pulse is noted as being diminished in frequency—
e.g., 86 before the descent, and 55 immediately after the ascent,"
a diminution no doubt due to the inhibitory action of the vagus
nerve, the centre of this nerve being excited by the want of
oxygen in the first stage of asphyxia.

As to the haemorrhages so frequently noted as occurring in
naked divers, we must bear in mind that the arterial pressure is
raised during the asphyxial period both by the powerful beats
of the heart and by vaso-constriction, while the venous pressure
is raised by the fixation of the thorax and cessation of the
respiratory movements, which further the return of blood to
the heart ; also by the compressive action of the powerful mus-
cular movements of the diver. The air in the mouth, nose, ears,
and lungs is compressed during the descent, and as the pressure
equals that of 4 atmospheres at a depth of 100 feet, the air therein
should be reduced in this case to one-fourth of its volume.
Owing to the rigidity of the wall of the nose and ear cavities, the
* Luftdruck Erkrankungen, Wien, 1900.



CAISSON SICKNESS

full reduction in volume, and corresponding equalization of
pressure within and without, may not take place there. If this
is so, the pressure of the air will be less than the pressure of the
water on the rest of the body, and a cupping effect must take
place. The ear is connected with the throat by a passage — the
Eustachian tube — and if this and the way into the nasal cavities
are freely open, the pressure will be equalized, and no cupping
effect occur. The volume of the air in the lungs will not be
sensibly reduced by the 2 used, for the CO, output will be of
about the same volume ; but during the stay at the bottom
some of the nitrogen and oxygen of the air enclosed in the cavities
must pass into solution in the blood and be carried to the tissue
fluids. On rapidly returning to the surface, there takes place an
expansion of the air which has been thus diminished in volume.
No cupping effect, however, can be produced thereby so long
as the diver keeps open the communications between the nose,
middle ear, and lungs, for the mobility of the diaphragm will
insure a reduction or increase of volume of the air in the thorax
in proportion to the pressure of the surrounding water. The air
in his lungs must be compressed to one-half its volume at 33 feet,
to one-third at 66 feet, to one-quarter at 99 feet. Therefore he
must fill his lungs well before diving, to prevent the over-dis-
placement of his heart by the ascent of the diaphragm. The
practised diver no doubt fills his lungs well, keeps open his
Eustachian tube by swallowing, and so times his stay at the
bottom that the asphyxia! congestion of the bloodvessels is not
brought to the rupture-point during the efforts of the ascent.
In the case of the whale, which sounds to depths of 200 fathoms
or more, it is an unsolved problem what happens to the air in
its lungs. Do the parts allow the full compressive action to take
place ? Is the air dissolved in the blood in proportion to the
partial pressure ? If so. what happens when the whale returns
to the surface ? The anatomical arrangements must either
allow compression of the lungs to the smallest size, or else water
in ust enter the lungs and bring about the compression of the air.
It i> impossible that any rigid structure should hold off the
pressure, for if this were the case, a cupping effect and haemorrhage
into the lungs would take place.

Some naked divers put wool soaked in oil in their ears. This
hinders the entry of water when the air in the auditory meatus
is compressed.



THE NAKED DIVER 7

The divers carry out vigorous movements under water, and
thus the time of submergence is very limited. The bearable per-
centage of carbon dioxide in the lungs is rapidly reached, and
about one minute seems to be the usual limit. By a few seconds'
deep breathing just before the dive they seek to prolong the time
as far as possible. It is said that by practice they extend the
time, and that the best divers may attain to two minutes at the
end of the sponge-fishing season.

The period which the naked diver can stay under water depends
on his power to withstand the excitatory effect of the carbon
dioxide and other acid in the blood, the increasing concentration
of which impels the respiratory centre into such a state of
exaltation that finally a point is reached at which it can no
longer be inhibited by voluntary effort. It must require much
practice and a nice judgment on the part of the diver to leave
the right margin of time for those efforts which are necessary to
attain the surface from any considerable depth.

The work of Haldane and other English physiologists has
demonstrated that the inspiratory centre is excited more or less
by the relative concentration of acid (the hydrogen ion) in the
blood. In conditions where there is want of oxygen, the oxidative
processes in the tissues do not proceed wholly to the end-products
— water and carbon dioxide — and half-way products accumulate,
such as lactic acid. The lactic and carbonic acids summate their
effect on the respiratory centre. The naked diver suffers not
only from the rising concentration of carbon dioxide in the blood,


1 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

Online LibraryLeonard Erskine HillCaisson sickness, and the physiology of work in compressed air → online text (page 1 of 22)