SPINAL ANÆSTHESIA.
Spinal Anæsthesia or _Analgesia_, consists in the production of
analgesia in the lower extremities and in the lower part of the trunk
by the injection into the subarachnoid space of an anæsthetic drug
which blocks the spinal nerves as they enter and leave the spinal
cord. The cord ends at the lower border of the first lumbar vertebra
and the subarachnoid space at the second sacral vertebra so that there
is a considerable area into which the injection may be made without
risk of injury to the cord. It is, in reality, a special variety of
regional analgesia, the anæsthetic being injected into that part of
the subarachnoid space which is occupied by the cauda equina. The
subarachnoid space of the medulla spinalis contains the cerebro-spinal
fluid and communicates above with the subarachnoid space inside the
skull and through the foramen of Magendie, with the ventricular system
of the brain. The subdural space of the medulla spinalis is merely a
capillary interval. At the upper end of the cauda equina the nerve
trunks of the two sides are separated by a median interval--containing
only the filum terminale--which has been termed the cysterna
terminalis. It is into this median space that the injection is made, in
order to avoid wounding the nerve trunks and to procure equal diffusion
of the anæsthetic to both sides of the middle line. If the injection is
made among the nerve trunks on one side, a unilateral anæsthesia may
result, the drug being prevented from diffusing freely to the other
side by the presence of the numerous nerves.
The ligamentum denticulatum forms an imperfect scalloped septum between
the posterior and the anterior nerve roots, passing from the surface
of the cord to the dura mater. The presence of this septum probably
explains the fact that the motor nerves are not affected with the same
constancy and to the same extent as the sensory roots.
Technique.
The drug which is most commonly employed in the Edinburgh school is
Tropacocaine, and the results of its use with proper technique are
eminently satisfactory. The dose of the drug for most purposes is ·07
gramme. Smaller doses are sometimes used but the larger dose gives
more constant anæsthesia and appears to be well within the limits
of safety. The dose is dissolved in 1 c.cm. of distilled water and
sufficient sodium chloride added to make a solution isotonic with the
cerebro-spinal fluid. A convenient method of obtaining the drug is
in glass ampoules, each ampoule containing one dose, which has been
carefully sterilised.
[Illustration: FIG. 53.--Needle and syringe for
spinal analgesia. Note the short oblique character of the
point of the needle.]
The syringe and needle employed are illustrated in Fig. 53.
The point of the needle must be sharp but short. If a needle with a
long slender point is employed, only part of the point may enter the
membranes; a free flow of cerebro-spinal fluid may then take place,
but when the injection is made part of the anæsthetic solution escapes
outside the membranes. The needle should he 3½ to 4 inches long and 1
m.m. in diameter. A stylet fits inside the needle and prevents it from
becoming blocked during the introduction. To prevent the possibility
of rusting, both needle and stylet should consist of hard nickel. The
barrel of the syringe must consist of glass so that the appearance
of the cerebro-spinal fluid can be seen. The Record type is very
satisfactory. The syringe usually supplied for spinal analgesia has
a capacity of 2 or 3 c.cm., but one holding 10 c.cm. is more useful.
Syringe and needle must be carefully sterilised by boiling in plain
water; any trace of soda causes decomposition of the drug. The ampoule
containing the tropococaine is sterilised in a strong antiseptic
solution so as to avoid the possibility of contamination of the hands
when the drug is being transferred to the syringe.
_Method of Injection._--The patient should be given a hypodermic
injection of ⅛ gr. of morphine and ¹⁄₁₅₀ gr. of scopolamine an hour
before the operation. There are a number of minor variations in the
method of making the spinal injection, but limitations of space forbid
a discussion of theoretical questions and of the relative merits of
the different procedures. Only one method, which has been found safe
and reliable, will be considered here. The injection is made in the
space between the third and fourth lumbar spines, the objective being
the mid-line of the subarachnoid space between the two divisions of
the cauda equina. The position of the patient is such that the spaces
between the lumbar spines are opened up as widely as possible. The
most convenient plan is to have the patient sitting on the table with
the head and shoulders bent well forward (_see_ Fig. 54.) If the
patient is unable to sit up, the injection may be made with him lying
on his side, with the knees drawn up and the shoulders bent forward.
[Illustration:
FIG. 54. Position for the injection. The cross
indicates the point at which the lumbar puncture is
made--about half an inch from the median plane and in the
space between the third and fourth lumbar spines.]
The skin of the back is carefully sterilised; painting with tincture of
iodine serves admirably. The ampoule containing the tropacocaine is
opened, and the drug sucked into the syringe through a spare cannula.
The loaded syringe is then placed on a sterile towel at the back of the
patient. With a little practice there is no difficulty in making the
lumbar puncture. The fourth lumbar spine is located by noting the level
of the highest point on the iliac crest--this may be indicated by an
assistant. A line joining the highest points on the two iliac crests
will pass through the tip of the fourth lumbar spine. When this process
has been carefully identified, the needle is introduced half-an-inch to
one side of the median plane and midway between the third and fourth
spine. Some surgeons prefer to go in exactly in the middle line to make
sure of entering the middle of the subarachnoid space, but in this
position the tough supra-spinous and interspinous ligaments are met
with, and to avoid the resistance of these it is best to keep a short
distance out from the median plane. By carefully noting the direction
of the needle, the cysterna terminalis can always be entered. The
needle is passed forwards, very slightly upwards, and slightly medially
so as to hit off the centre of the subarachnoid space. As the needle
passes through the ligamentum flavum, there is a sudden diminution of
resistance and immediately afterwards the point of the needle lies in
the subarachnoid space. The passage of the needle through the membranes
is sometimes accompanied by a slight pricking pain.
The stylet is withdrawn at this stage and the cerebro-spinal fluid
usually trickles out drop by drop. The syringe is picked up, carefully
emptied of air bubbles, and fitted on to the needle. The piston is
withdrawn until the syringe is filled with cerebro-spinal fluid, which
mixes freely with the anæsthetic solution, and the contents then
slowly injected. The 10 c.cm. syringe is to be preferred for this
purpose as it is essential to mix the tropacocaine thoroughly with the
cerebro-spinal fluid. If the smaller syringe is used, it should be
refilled with cerebro-spinal fluid and emptied a second time so as to
ensure thorough diffusion of the drug. The needle is then withdrawn and
the puncture sealed with collodion.
The injection should never be made until a free flow of cerebro-spinal
fluid is obtained, since this is the only certain indication that the
needle has entered the subarachnoid space. If failure is met with in
the space between the third and fourth spines, the interspinous space
above or below should be tried.
After the injection has been completed the patient is placed flat on
his back and then lowered into the Trendelenburg position. Analgesia
appears first in the scrotum and perineum, extends down the medial
side of the leg to the foot, then appears on the front of the leg, and
travels up to the groin and the lower part of the abdomen. The progress
of the analgesia is tested from time to time by lightly pinching
or pricking the skin, the patient’s eyes being screened. When the
analgesia reaches the level of the nipples, the patient is raised into
the horizontal position and the the operation may be commenced. Some
surgeons object to the lowering of the head as rendering paralysis of
the respiratory centre from upward diffusion of the drug more likely.
If tropacocaine is used in the dosage indicated and the table elevated
when the anæsthesia reaches the nipple line, there seems to be little
risk of this complication. If analgesia is only desired in the lower
extremity, the lowering of the table may be omitted; but if a good
anæsthesia is desired above the level of the groin, it should always be
carried out.
Analgesia is complete in five or ten minutes as a rule. The duration
varies from three-quarters of an hour to an hour and a half. If a
preliminary hypodermic injection of morphine and scopolamine has been
given, the patient lies quietly and patiently until the operation is
completed. In some cases the patient actually drops off to sleep from
the effects of the morphine. It is not uncommon to observe a temporary
nausea and faintness about fifteen or twenty minutes after the
injection has been made, and it is good practice to give the patient a
little brandy and water at this stage.
Complications and After-Effects.
A great deal has been written in the past with regard to unpleasant
results of spinal analgesia, but most of these would appear to have
been the result of faulty technique or of the use of an impure or
irritating drug. When tropacocaine is used in the manner described, the
usual result is that, except for occasional nausea and faintness at
the commencement, the patient has a comfortable, painless operation,
and a recovery which is unmarred by the sickness and other distressing
symptoms which are so common after general anæsthesia.
_Deaths_ have been recorded, and these have been ascribed to
the drug having travelled too high and brought about paralysis of
the respiratory centre in the medulla oblongata. Too much importance
has probably been ascribed to these fatal cases. They have been most
common in patients greatly enfeebled by shock, old age, or debilitating
illness, who are liable to die during the operation whatever anæsthetic
is used. Thousands of cases have been recorded without a death, and
in the hands of surgeons of skill and judgment fatal cases are almost
unknown.
An occasional complication is severe _headache_ which may
persist for a week or longer. Other complications are all exceedingly
rare; paralysis of the lateral rectus muscle of the eyeball or of
other ocular muscles has been recorded, and is probably due to toxic
bye-products which are the result of impurity of the drug. Persistent
nausea and paralysis of the bladder and rectum and even of the lower
extremities have also been recorded, but are to be regarded as the
greatest rareties, and probably due to impurity of the anæsthetic.
Indications.
Spinal analgesia may be used for any operation at or below the level of
the umbilicus. Excellent anæsthesia is obtained for the operation for
radical cure of umbilical hernia, but anæsthesia above this level is
not so constant, and is regarded by many authorities as unsafe.
The procedure is of special value in cases in which a general
anæsthetic is unsafe:--(1) In old enfeebled patients suffering from
strangulated hernia, enlarged prostate, disease of the female pelvic
organs, and other conditions where anæsthesia is necessary below the
umbilicus. (2) In patients who are already suffering, or who are likely
to suffer, from severe shock. The drug has the same effect on the nerve
trunks of the cauda equina as on the peripheral nerves--it causes
blocking of the centripetal sensory impulses which are such a potent
factor in the causation of shock.
(3) In diabetic gangrene spinal analgesia is the safest form of
anæsthesia to employ.
Contra-Indications
Children up to the age of fourteen or so are apt to be frightened,
and spinal analgesia is better avoided except in special cases. It
is contra-indicated also in septic conditions on account of the
possibility of septic meningitis resulting from metastasis of the
infection, the drug having possibly the action of lowering the vitality
of the cord and meninges. In tuberculosis and syphilis it is better
avoided for the same reason. It should not be used where organic
disease of the spinal cord or brain is already present.
Analgesia Produced by Freezing.
A transient analgesia can be produced by freezing the skin. An ether
spray was formerly employed, but was found to be troublesome and
inconvenient. The most convenient procedure consists in freezing the
part by means of a spray of ethyl chloride. This drug is supplied in a
glass cylinder with a very fine outlet so that it breaks up into a fine
spray as it escapes. The cylinder is held about 8 or 10 inches from the
patient’s skin, and pressure applied with the thumb to a stopcock on
the neck of the cylinder. Under the influence of the heat of the hand
the liquid escapes in a fine jet which impinges on the patient’s skin.
Freezing takes place in a few seconds, the frozen patch becoming hard
and white. The freezing can be hastened by blowing on the skin.
This method is only suitable for the opening of small abscesses and
other procedures requiring a very short anæsthesia. The anæsthesia is
very imperfect, and only lasts for a few seconds. Many patients appear
to have as much pain with this form of anæsthesia as without it.
APPENDIX I.
SOME EXPERIMENTAL OBSERVATIONS BY THE AUTHOR UPON THE
PHYSICAL FACTS OF ETHER EVAPORATION.
The apparatus was very simple. It consisted of a pump which would
propel air towards the ether bottle; a glass bottle containing ether,
the roof of which was pierced by two tubes, one of which carried the
air from pump to bottle, and the other from bottle to a Waller’s tube,
where it was collected. The percentage of ether in the air was then
estimated by Waller’s gravimetric method. The ether jar stood in a
water bath which could be either left otherwise empty or filled up
with water of known temperature. The following tables show some of the
results. In each case, the air was propelled for five minutes, by which
time the cooling effect upon the ether was very marked; the figures
given are averages taken from several observations.
TABLE A.
AIR BLOWING OVER SURFACE OF ETHER.
+---------------------+----------------+----------+--------------+----------+
| Temperature of | Quantity of | Rate | Temperature | |
| Bath (Fahr.) | ether before | of | of ether |Percentage|
| before experiment. |experiment. | pump. |(Fahr.) at end|obtained. |
| | | |of experiment.| |
+---------------------+----------------+----------+--------------+----------+
| 75 | 100 c.c. | 30 | 50 F. | 12·7 |
| 85 | 100 c.c. | 30 | 52 F. | 12·8 |
| 75 | 100 c.c. | 90 | 45 F. | 8·7 |
| 85 | 100 c.c. | 90 | 45 F. | 8·8 |
| No water in bath | 100 c.c. | 30 | 32 F. | 8·2 |
| No water in bath | 100 c.c. | 90 | 23 F. | 5·4 |
| No water in bath | 200 c.c. | 30 | 38 F. | 9·6 |
| No water in bath | 200 c.c. | 90 | 29 F. | 6·6 |
+---------------------+----------------+----------+--------------+----------+
TABLE B.
Showing increased percentage obtained by “bubbling through” instead of
“blowing over” ether--
WATER BATH AT 75° FAHR.
Quantity of ether. Rate of pump.
100 c.c. 30
Air blown over surface of ether gave percentage of ether 12·8
Air bubbled _through_ ether 23·8
TABLE C.
Showing amounts of ether vaporised at varying pump rates. In each case,
the temperature of the water bath was 75, and the initial amount of
ether was 100 cc.--
Pump Amount of Ether
Rate. Vaporised.
30 30 c.c.
90 38 c.c.
These experiments justify one in drawing the following conclusions:--
1. The effect of a water bath has a marked effect in increasing
the strength of the vapour yielded, but small variations in the
temperature of the bath (as between 75 and 85 Fahr.) have but
little effect.
2. If ether is vaporising quickly, it cannot pick up heat from
the water bath as quickly as it is losing its own heat. Though
not shown in the tables, the actual loss of temperature on the
water bath was small--about 2 degrees Fahr. during the five
minutes experiment.
3. The more forcible the blast of air blown over or through
the ether, the less the percentage of ether yielded. Table C
shows that this loss of percentage is not compensated for by an
increase in the total amount vaporised.
Of course, these results only apply to the case of a strong current
of air. If the current of air were _very_ small, the ether could
pick up heat as fast as it parted with it, and within moderate degrees
a little increase of the air stream would increase the total amount of
ether vaporised without reducing the percentage strength.
These results are of some practical importance in connection with
so-called “vapour anæsthesia” as given for instance by Shipway’s
instrument (page 90), and in devising and using the ether chambers of
intratracheal apparatus.
APPENDIX II.
THE PERCENTAGE STRENGTH IN OPEN ETHER.
Hewitt and Syme (_Lancet_, 27th Jan. 1912) estimated the percentage
of ether obtainable from an open mask with varying materials and
quantities of the drug. The results are tabulated below:--
A.--A WHOLE MASK JUST MOIST.
Material stretched Number of Percentage
on mask. layers. obtained.
Gauze 4 11
8 11·4
12 11
Flannel 1 8·0
2 8·0
Lint 1 10·0
B.--WHOLE MASK WET.
Gauze 4 12
8 13·4
12 14·0
Flannel 1 8·0
2 8·0
Lint 1 8·0
By excessive douching the observers were able to obtain 17 per
cent.
In these results, air and ether vapour were drawn by a pump through
the material to imitate the inspiration, but no attempt seems to have
been made to imitate expiration. The effect upon the material used of
moisture condensed from the expired air is not taken into account
in these experiments. This is a serious hiatus in the argument,
particularly as regards lint. This material in actual use rapidly
becomes quite sodden, and ether will not vaporise from it properly.
In spite of this fault, these observations may probably be taken as
being reasonably accurate.
With them may be compared the figures of Karl Connell, who, working
with quite accurate methods, estimated the percentages of ether
necessary to induce and maintain anæsthesia:--
Period of Anæsthesia. Percentage.
First 5 minutes (_i.e._ induction) 18
Next 25 „ 14
Next 30 „ 12
Next 60 „ 12·8
“Bad” subjects on the average required an extra 4 per cent. during
first half hour, feeble patients required 2 per cent. less.
(_Journal_ of the American Medical Association, 22nd March 1913).
APPENDIX III.
THE ACTION OF ANÆSTHETICS UPON THE BLOOD.
_The Blood Gases in Anæsthesia._
Buckmaster and Gardner (_Journal of Physiology_, vol. xli., p. 246),
analysed the blood gases in various stages of chloroform anæsthesia,
and some of their results are shown below in tabular form. They show a
very definite reduction in the oxygen content of the blood. So far as
one gathers from the text of the paper, the animals were not subjected
to any considerable trauma during the progress of the anæsthesia, so
that the figures arrived at with regard to the CO_{2} content do not
bear upon the Acapnia question. If there was no trauma, there would be
no deep breathing, and a reduction of CO_{2} could not be expected.
+---------------------------+------------------+-------------------+---------------+
| |Average volume in |Average composition| |
| |c.c. per 100 c.c. | per cent. | Relation |
| | of blood | of gas | of |
| |------+-----+-----+-------------------|O_{2} to CO_{2}|
| |CO_{2}|O_{2}|Nitr.|CO_{2}| O_{2}|Nitr.| |
+---------------------------+------+-----+-----+------+------+-----+---------------+
|Normal cats. | 25·07|13·60| 1·00| 63·2| 34·28| 2·52| 1 to 1·84 |
| | | | | | | | |
|Reflexes just re-appearing | 29·02|11·49| 1·33| 65·06| 25·44| 2·87| 1 to 2·55 |
| | | | | | | | |
|Reflexes just disappearing | 29·57| 7·78| 2·15| 69·14| 18·17| 5·09| 1 to 3·8 |
| | | | | | | | |
|2nd Stage Anæsthesia | 36·00| 8·14| 1·49| 71·27| 16·12| 2·95| 1 to 4·32 |
+---------------------------+------+-----+-----+------+------+-----+---------------+
_Other Blood changes in Anæsthesia._
Hamburger and Ewing (_Journal_ of the American Medical Assoc. 1908)
examined the blood changes incidental to surgical anæsthesia. Their
results may be condensed as follows:--
_Nitrous Oxide._--Hæmoglobin is not permanently decreased and no anæmia
follows the administration. Hæmolysis is not increased. The coagulation
time of the blood is not always affected in the same direction. Usually
it is slightly increased.
_Ether._--The hæmoglobin is slightly reduced and anæmia persists for
seven to ten days. Hæmolysis is not however materially increased.
There is some evidence of blood inspissation. The coagulation time is
markedly increased.
_Chloroform._--The hæmoglobin is reduced and a distinct anæmia
produced. Hæmolysis is definitely increased. There is a slight increase
in the coagulation time.
INDEX.
A
Abdominal operations, ix, 7
local anæsthesia in, 187
Abdominal muscles, rigidity of, 19
Abnormalities of anæsthesia, minor, 38
major, 140
Acapnia, 10, 29, 39
Accidents of anæsthesia, 140
Acetonuria, 153
Acidosis, 153
Adenoids, 127, 166
in status lymphaticus, 148
Adrenalin, 175
danger of, with chloroform, 113, 166
Aedentulous patients, 23
After-effects of anæsthetics, _see_ Sequelae
Ages, dosage of morphia at various, 45
selection of anæsthetic at various, 164
Airshaft, natural, 96
Airway, natural, 15, 31, 114, 145
artificial, 23
Alcoholics, anæsthesia in, 2, 87, 103, 137, 165
Alkaloids, 12, 43, 88, 103
Aneurysm, 56
Anoci-association, 11
Anoxæmia, 15
Arm, management of in anæsthesia, 157
regional anæsthesia of, 181
Arteries, spouting of, x, 37
Arterio-sclerosis, 56, 167
Artificial respiration, 146
Asphyxia, 15
Athetosis, 38
Atropine, 43, 45, 112, 147
Auer and Meltzer, 96
B
Barth 3-way tap, 50
Bicarbonate of soda in acidosis, 156
Bladder, reflexes from, 39, 168
local anæsthesia in operations upon, 190
Blistering, by chloroform, 109
Blood, changes in, during anæsthesia, 207
spouting of, from cut arteries, x, 37
Blood-pressure, in natural sleep, 1
in shock, 6
in asphyxia, 17
in nitrous oxide, 46
in ether, 75
in chloroform, 110
in ethyl chloride, 122
clinical observation of, 37
Blowing respiration, 34, 89
Boothby, on ether percentages, 99
Boyle, Mr Leonard, 70
Brachial plexus, nerve blocking in, 181
Brain, _see_ Nervous System
local anæsthesia for operation upon, 191
Breath-holding, 34, 112, 114
Breathing, deep (_see_ Acapnia)
Bronchitis, 150
C
Carbon-dioxide, 10, 18, 206
Cardiac cyanosis, 37
Cardiac disease, 107
Cardiac failure (_see_ Syncope)
Castration, anæsthesia in, 169
C.E. mixture, 84, 134, 137
Cells, nerve, changes in, 5
Centripetal impulses, 6
Children, 45, 94, 125, 164
Chloretone, 93
Chloride of ethyl (_see_ Ethyl Chloride)
Chloroform, administration of, 113
decomposition of, 109
delayed poisoning by, 153
physiology of, 109
Choice of anæsthetics, 162
Circulation, observation of, x, 37
in shock, 10
in asphyxia, 17
in valved breathing, 29
in nitrous oxide, 46
in ether, 75
in chloroform, 110
in ethyl chloride, 122
in C.E. mixture, 131
failure of (_see_ Syncope)
Circumcision, anæsthesia in, 169
Clarke’s apparatus, 69
Clenching of Jaws, 15, 24
Clinical phenomena of asphyxia, 18
of normal anæsthesia, 33
Closed ether, 78
Closed method, features of, 29
Clover’s inhaler, 78, 138
Cocaine, 170
Collapse (_see_ Syncope)
Conduction of nerve impulses, 3
Connell, Karl, 90, 205
Conjunctival reflex, 31, 35
Convulsions, 17
Corneal reflex, 32, 35
Crile, Prof., 5, 9
Crowing respiration, 16, 169
night crowing, 148
Cyanosis, 18, 37, 53
Cylinders for nitrous oxide, 43
for oxygen, 64
D
Dangers of chloroform, Prof. L. Hill upon, 120
Death, causes of, 17, 110, 140, 144, 148
Decomposition of chloroform, 109
of ether, 74
Deep breathing, 10
Degrees of anæsthesia, 31
Dental anæsthesia, 54, 57, 128, 131, 163
Depth of anæsthesia, 36
Dextrose in acidosis, 156
Difficulties of anæsthesia, major, 140
minor, 38
Dilatation of pupils, 5, 17, 35, 53, 66, 125, 136, 141, 143
Disease, relation of anæsthesia to, 166
acute infectious, 168
Dislocations, anæsthesia in reduction of, 164
Dorsal position, 157
Dosimetric method for chloroform, 114
for ether, 90
Dott, Mr N., direct laryngoscope, 104
Douche method, 20
Dread (_see_ Fear)
Drop bottles; chloroform, 117
ether, 83
Drop method, 30, 83
Drugs for local and spinal anæsthesia, 170 to 174
E
Emphysema, 167
Empyæma, 167, 187
Enema, before operation, 42
Ether, 74, _et seq._
closed, 78
intratracheal, 96
open, 83
physiology of, 75
rectal, 93
warmed vapour, 90
Ether, respiratory sequelæ of, 150
Ether tremor, 38
Ethyl chloride, 122, _et seq._
combined with nitrous oxide, 128
freezing anæsthesia by, 200
Eucain, 174
Excitement (_see_ Struggling)
Extraction of teeth (_see_ Dental Anæsthesia)
Eye reflexes, definition of, 31
F
Face-down posture, 157
Face, adaptation of masks to, 21, 52, 84
Face-pieces for nitrous oxide, 51
False anæsthesia, 41
Faradism of motor nerves in anæsthesia, 3
Fat patients, 158, 165
Fatty changes after anæsthesia, 153
Fear, effects of, 9
prevention of, 11, 43, 88
Feeble patients, 168
Ferguson, Dr., W. J., 87
Fingers, regional anæsthesia for, 184
Flame, open, dangers of, 74, 104
Forceps, tongue, 24
Food before anæsthesia, 42
Foreign bodies in the larynx, 16
Freezing analgesia, 201
Fright (_see_ Fear)
G
Gags, 25
Gardner, Mr Bellamy, 23, 24, 83
Gas and air, 54
Gas and ether, 138
Gas and ethyl chloride, 128
Gas-oxygen, 60
Gasping, 40
Genito-urinary operations, 168
Glossotilt, 24
Glottis, spasm of, 16, 20, 26, 105
Goitre, anæsthesia for, 160, 185
Goitre, exopthalmic, 9, 167
Grey and Parsons on shock, 6
Guy, Dr Wm., 128
Guy-Ross, gas oxygen method, 131
Gwathmey, warmed ether vapour, 90
oil-ether, 93
H
Hæmorrhage, as a factor in shock production, 9
observation of, by anæsthetist, x, 37
Hæmorrhoids, local anæsthesia for, 191
Harcourt, Vernon, 114
Head and neck operations, position for, 158
Head and neck, raising, 152
lowering, 110, 145
extra pillow in deep chested patients, 157
Heart, failure in asphyxia, 17
observation of, 37
action of ether upon, 75
of chloroform upon, 110
of ethyl chloride upon, 122
failure of, in secondary syncope, 144
Heart disease, anæsthetics in, 167
Henderson, Yandell, 10, 29
Hernia, local anæsthesia in, 189
Heroin, 44
Hewitt, Sir Frederick, 22, 50, 62, 81, 137
Hill’s direct laryngoscope, 104
Hill, Prof. Leonard, 111, 120
Hornabrook, 87, 123
Hydrochloric acid, as an impurity in chloroform, 109
Hypnotics, 12, 42
Hypodermic medication, 12, 42
I
Impurities of anæsthetics, 74, 109, 122
Infiltration analgesia, 175
Inhalers, Clover, 78
Clarke, 68
Guy, 128
Guy-Ross, 130
Hewitt, 50, 62, 81
Junker’s, 115
Ormsby, 81
Paterson, 58
Rendle, 135
Inhibition, vagal, 111, 143
Intestinal obstruction, 141, 189
Intranasal surgery, 160, 166, 192
Intratracheal method, 96
Kelly’s instrument for, 100
Shipway’s, 101
Inversion, Leonard Hill’s experiments upon, 110, 111
J
Jactitations, 53
Jaundice, 154
Jaws, clenching of, 15, 26
falling back of, 16
operations upon, 166
management of, in anæsthesia, 23, 85
Joints, anæsthesia in dislocation of, 164
Junker’s inhaler, 115
K
Kidney, position for operations upon, 168
Kelly’s intratracheal instrument, 100
L
Labour, anæsthesia in, 44, 169
Lane, Sir Arbuthnott, 14
Laryngeal stridor, 16, 20, 26, 40, 169
Levy, Goodman, 112, 145
Light anæsthesia, dangers of, in chloroform, 9, 112
Levy’s views, 113
Light reflex, 32
Local anæsthesia, 170 _et seq._
Lowering of head and shoulders, 110, 145
Lumbar puncture, site for, 196
Lungs, ventilation of, by normal breathing, 96
by intratracheal method, 97
Lymphatism, 148
M
Malcolm, J. D., 9
Marshall, Dr Geoffrey, 70
Masks for chloroform, 110
for ether, 82
for perhalation method, 28
Massage of heart, 148
Mechanical asphyxia, 15
Meltzer and Auer, on intratracheal method, 96
Menstruation, 169
Micturition before nitrous oxide, 51
Mixtures, C. E., 84, 134, 137
of nitrous oxide and oxygen, 60
of nitrous oxide and ethyl chloride, 128
Morphine, 12, 43, 152
Mouth, breathing through, 22
Mouth, operations upon, 165
Mouth props, 22
Mucus in air passages, 40
Musculo-spiral paralysis, 157
Muscles in anæsthesia, ix, 3, 19, 34
Muscle tone, 3, 19, 53
N
Nasal breathing, 23, 166
Naso-pharyngeal catarrh, 151
Nasal methods of giving nitrous oxide, 57
Nasal tube for Junker’s bottle, 119
Neck, position of, 20
relaxation of muscles of, 21
posture for operation upon, 159
tumours and inflammatory swellings in, 7, 166
Nephritis, influence of, upon choice of anæsthetics, 77, 168
Nervous system, effects of anæsthetics upon, 2, 75
Nerves, peripheral, unaffected by anæsthetics, 3
Nerve blocking, 12, 179
Night-crowing, 148
Nitrous oxide, 46
with air, 54
with ether, 138
with ethyl chloride, 128
nasal, 57
physiology of, 46
contra-indications to, 56
Nitrous oxide and oxygen, 8, 12, 60
various systems for, 67, 70, 130
for use in major surgery, 72
with ethyl chloride, 131
O
Obesity, 158, 165
Obstruction, intestinal, 141
respiratory, 15, 141
Oil ether, Gwathmey’s method of, 93
Oligæmia in shock, 10
Omnopon, 44
Open method, definition of, 28
chloroform, 117
ether, 83
ethyl chloride, 123
O’Malley’s technique for intra-nasal surgery, 160
Ormsby’s inhaler, 81, 137
Over-dosage, 36, 110, 144
with nitrous oxide, 54
Oxygen, reduction in blood in anæsthesia, 206
as a relief in asphyxia, 27
to old patients, 165
with nitrous oxide (_see_ Nitrous Oxide and Oxygen)
with nitrous oxide and ethyl chloride, 130
P
Paralysis, musculo-spiral, 157
Patella reflex in anæsthesia, 3
Percentages of chloroform and ether required in anæsthesia, 6
of chloroform, 111
of ether, 86, 99, 201, 204
Perhalation method, definition of, 28
ether (_see_ open Ether)
Phenomena of anæsthesia
normal, 33
abnormal, 38
of nitrous oxide, 52
of ethyl chloride, 125
Pericarditis as a cause of death in anæsthesia, 168
Phillip’s artificial airway, 23, 160
Physics of natural respiration, 96
Physiology of anæsthetic drugs, 1
of asphyxia, 17
of chloroform, 109
of ether, 75
of ethyl chloride, 122
of nitrous oxide, 46
Phthisis, 167
Pneumonia, post anæsthetic, 157
Position in anæsthesia, 157
Positive pressure in nitrous oxide, 52
in nitrous oxide and oxygen, 66
Post-chloroform poisoning, 153
Post anæsthetic complications, 150
Pregnancy, anæsthesia in, 169
Preliminary hypodermic medication, 11, 43, 152
Preparation of patient, 42
Primary syncope, 110, 143
Protection from shock by general anæsthetics, 8
Pulse, rate in shock, 6
clinical observation of, 37
Pupil, light reflex of, 32
size of, 35
in asphyxia, 17
Purging before anæsthetics, 40
Q
Quinine and urea hydrochloride, 174
R
Rebreathing method, 18
in nitrous oxide, 68
Rectal administration of ether, 93
Rectal saline, 42
Reflexes as a cause of shock, 4, 6
order of disappearance of, 3
Reflex, conjunctival, 31, 35
corneal, 32, 35
light, 32, 35
patella, 3
skin, 37
Reflex syncope, 8, 112, 145
Regional anæsthesia, 179
Renal disease, 163
Rendle’s cone, 135
Repeated administrations, 60, 156
Respiration, arrest of, 142
artificial, 146
blowing, 34, 89
crowing, 16
depressed, 39, 43
effect of morphia and chloroform upon, 43, 86
normal, 34
obstructed, 15, 141, 166
Respiration, physics of natural, 96
reflex arrest of, 39
Respiratory abnormalities, minor, 39
major, 141
Respiratory system, effects of ether upon, 76
after-effects of anæsthetics upon, 150
Rigidity of muscles in asphyxia, 19, 38, 39
in second stage, 33
S
Saline injections, per rectus, 42
subcutaneous, 14
Schimmelbusch’s mask, 28, 116
Scopolamine, 44, 103
Secondary syncope, 17, 138, 143
Secretion of mucus, 40, 76
of urine, 168
Sedatives, 12, 42
Selection of anæsthetic, 162
Semi-open method, 28
Septic cases, 9, 60, 156, 168
Sequelæ of anæsthesia, 100
Sex, relation to anæsthesia, 165
Shipway, Dr, 91, 101
Shock, 5
difference between syncope and, 142
Short, Mr Rendle, 154
Sickness (_see_ Vomiting)
Sighing, 40
Sight-feed machines for gas-oxygen, 70
Signs of anæsthesia, 36, 53, 65
Silk, Dr J. W., 23, 87
Single dose anæsthetics, 30, 163
Sitting posture, 21, 158
Slow respiration, 39
Spasm, muscular, 19
of jaw muscles, 15
of larynx, 16, 26, 169
Specific gravity of chloroform, 109
of ether, 74
Spinal anæsthesia, 193
Stages of anæsthesia, 31
Starvation, a cause of shock, 9
of acidosis, 155
Status lymphaticus, 148
Stertor, 40, 53
Stimuli from field of operations, 6
Stomach tube, before operation, 141
Stovaine, 173
Stridor, 16, 26, 40
Struggling, 34
Strychnine, 147
Subcutaneous saline, 14
Swallowing, movements of, 33
Sylvester’s method of artificial respiration, 146
Syncope, 142
Syringe for local anæsthesia, 176
for spinal anæsthesia, 176
T
Teeth, danger of dropping of into larynx, 16
extraction of, 54, 57, 128, 131, 163
Teter, Dr., on nitrous oxide and oxygen, 68
Thomson, Prof. Alexis, 12, 158
Thomson, Torrance, on intratracheal anæsthesia, 96
Thoracic operations, local anæsthesia in, 186
Three-way tap for nitrous oxide, 50, 128
Thyroid gland, _see_ Goitre
Time for operations, 42
Time afforded by single dose anæsthetics, 163
Tongue falling back of, 16
forceps for, 24
operations upon, 97, 118, 166
local anæsthesia for, 191
Tonsils and adenoids, 127, 166
Trachea, mucus in, 40
pressure upon, 17
Trachetomy, 142, 185
Tremor, ether, 38
Trendelenberg posture, 158
Tropacocaine, 173
Turner, Dr Logan, 125
U
Urine, secretion of prevented by morphia, 168
V
Vagus nerve, 110, 145
Valved method, features of, 29
Vapour method, ether, 90
ethyl chloride, 125
Vaso-motor system, in shock, 9
in asphyxia, 17
in nitrous oxide, 46 (and _see_ Physiology)
Veins, large, emptying into heart, 10
engorgement of, 20, 151
Venesection in syncope, 147
Veronal, 12
Vicious circle of asphyxia, 20
Vital medullary centres, 3
Vomiting, 140, 152
impending, 39, 141
W
War, anti-shock, measures in, 11
lessons of, 61, 151
Warming anæsthetic vapours, 62, 90, 101
Wedge for opening clenched jaws, 25
Withdrawal of anæsthetic, for stridor, 26
for breath holding and struggling, 34
for syncope, 145
FOOTNOTES:
[1] This can be done to a very limited extent indeed if the ordinary
valves here described are used. _See_ page 68.
[2] A safeguard provided on some machines is a side lead from the
oxygen supply direct to the facepiece whereby pure oxygen can be given
if required.
[3] The amount of oxygen in a cylinder is designated in terms of cubic
feet. A cylinder which would hold 100 gallons of N_{2}O, will contain
30 cubic feet of oxygen.
[4] In the figure the Clover is shown with gas valves and 2-gallon bag,
arranged for “gas and ether.”
[5] Trans. xvii. Internat. Med. Cong. Sub-sect. (vii.) Part i.
[6] _Journal_ Amer. Med. Assoc., Sept. 1913.
[7] Trans. xvii., Internat. Med. Cong. Sub-sec. (vii.), Part i.
[8] Trans. xvii., Internat. Med. Cong., Sub-sec. (vii.), Part ii.
[9] Trans. xvii., Internat. Med. Cong., Sub-sec. (vii.), Part I.
[10] The student should be careful to be sure that the bulb is attached
to the _inlet pipe_: if by accident it be slipped on to the outlet
pipe, the first compression of the bulb will eject a stream of liquid
chloroform from the instrument.
[11] The author described this method in a paper read before the
Scottish Branch of the British Dental Association, and afterwards
published in the _Journal_ of the Association under the title “The
Edinburgh System of Dental Anæsthesia.” To the use of this term Dr J.
H. Gibbs, of Edinburgh, took strong exception in a letter to the Editor
of the _Journal_. The author has and had no desire to convey the
impression that this system was universally used in Edinburgh, but
simply that it is the method taught by Dr Guy, Dean of the School, to
the students in the Extraction Room.
Transcriber’s Notes:
1. Obvious printers’, punctuation and spelling errors have been
corrected silently.
2. Where hyphenation is in doubt, it has been retained as in the
original.
3. Some hyphenated and non-hyphenated versions of the same words have
been retained as in the original.
4. Superscripts are represented using the caret character, e.g. D^r. or
X^{xx}.
5. Italics are shown as _xxx_.
6. Bold print is shown as =xxx=.