ETHER.
The drug commonly known as ether and otherwise described as ethylic
ether or sulphuric ether, has a chemical formula (C_{2}H_{5})_{2}O.
It is a transparent colourless fluid with a specific gravity of ·720
to ·723. A brand much used in the States has an S.G. of ·713 only, a
point which is greatly emphasised by its supporters, who claim that it
volatises quicker and therefore is more powerful in action. The author
has in actual practise not found much difference between this brand and
any good British one.
Ether is highly inflammable and volatilises readily at ordinary
room temperatures. Its boiling point is 96° to 98° Fahr. Whether
evaporating from a fabric such as gauze, or from bulk in a jar, ether
cools very rapidly, and the fall in temperature soon reduces the
ease of its volatisation. This point is of some practical importance
in anæsthetics, and some years ago the author made a number of
observations, hitherto unpublished, with a view of ascertaining some
definite facts in this connection. His results will be found in
Appendix I.
_Ether vapour_ is heavy--two and a half times heavier than air. It
therefore tends in a room to flow towards the floor, and to remain
for some time unmixed with the general atmosphere. Since it is highly
explosive, this constitutes a definite danger if any naked light or
open fire is present. Everyone who handles ether should bear in mind
these physical peculiarities of its vapour.
Ether is affected by prolonged exposure to bright sunlight, and also by
prolonged bubbling through it of air, nitrous oxide, or oxygen. Ether
which has been subjected to any of these measures should be inspected
before being put back into reserve, and if any brown discoloration
is noticed, it should either be sent to the hospital laboratory for
redistillation, or presented to the theatre sister for use as a
cleaning agent. Such contributions are always gratefully received.
Most of the ordinary impurities of ether are acid in reaction, while
ether itself is absolutely neutral. Any specimen which turns litmus
paper red should be sent to the laboratory for examination.
Sources of Supply.
Ethylic alcohol may be prepared either from ethyl alcohol or from
methylated spirits. In the former case it carries, however, the cost
of the duty imposed upon potable spirit, and since perfectly good
anæsthetic ether can be prepared from the latter source, it is waste of
money to use the more expensive article.
Physiology.
Ether acts upon the nervous system like other anæsthetics: as compared
with chloroform, however, the stage of excitation of each centre
before its paralysis is apt to be marked. There is, therefore, in some
subjects, a greater tendency to struggle; healthy subjects properly
handled do not show much evidence of irritation of the cerebrum. All,
however, show some evidence of stimulation of the respiratory centre,
which is not prolonged. _Prolonged deep and rapid respiration under
ether is due to other causes than the action of the drug itself._ It
is of course seen in “closed ether,” but the active agent is excess of
CO_{2}, not ether.
The working margin of safety in ether, _i.e._ the stage between loss of
spinal reflexes and the poisoning of respiratory centre is much wider
than in chloroform.
Some experiments of Waller made many years ago showed that upon nerve
tissue, ether acts much less powerfully than chloroform: in the
proportion, he found, of one to seven or eight. These laboratory
results have received entire confirmation by later workers who have
estimated the actual vapour strength required of either drug to produce
or maintain anæsthesia. Roughly, to induce anæsthesia, we require 2 per
cent. chloroform, or 16 to 18 per cent. of ether (_see_ Appendix II.).
The Circulation.
The first effect of ether is a temporary stimulation of the heart,
which beats more rapidly and more strongly, thus raising the blood
pressure. This effect is not very prolonged; like all other drug
stimulation, it is followed by depression. In the healthy subject
properly anæsthetised, such depression is very moderate in degree, and
in a normal administration it is probable that the heart, after the
first few minutes, is acting very much at its normal speed and force.
Ether is, however, a marked vaso-dilator, and the net result upon blood
pressure is a slight fall after the first few minutes.
If the method in use is “closed,” the pressure remains slightly raised
for some considerable time, usually throughout the administration. The
slight anoxaemia induces a vaso-constriction; and the CO_{2} excess,
in the view of Henderson (_see_ page 10), maintains a good return of
venous blood to the heart and a satisfactory cardiac output. For a note
of certain blood changes resulting from ether and other anæsthetics
(_see_ Appendix III.).
Respiratory System.
In addition to the effect upon the medullary centre already referred
to, ether effects the respiratory tract more profoundly than other
anæsthetics. The mucous membranes are irritated, and in some cases
there is a great outpouring of mucous. Though usually limited to the
upper part of the tract (nose, pharynx, and trachea), the irritation
sometimes extends deeply into the chest, affecting even the small
bronchioles. These unpleasant effects of ether are in the great
majority of cases, quite transient: after the first ten minutes no
addition to the secretions is noticed. In a minority, however, the
effect persists, the whole chest is filled with moist sounds, and
persistence with the drug is impossible.
_The kidneys_ are always slightly irritated by ether, and if they
are or recently have been subject to inflammatory disease, a very acute
exacerbation is apt to follow the use of the drug. In the healthy
kidney this is not to be feared, nor does it seem to be an appreciable
danger where one kidney is sound, even if the other is the seat of
gross organic disease necessitating its drainage or removal.
[Illustration: FIG. 23.--Clover’s ether inhaler, with nitrous
oxide attachment.]
Methods of Administration.
Many methods have been tried, but those which at present hold the field
are--
(1) Closed Ether.
(2) Open Ether, more properly called the Perhalation Method.
(3) The “Vapour” Method.
(4) The Rectal Method (Gwathmey’s oil-ether).
(5) The Intratracheal Method, described separately in Chapter
X.
[Illustration: FIG. 24.--Diagram of a vertical section through
the middle of Clover’s Inhaler. A. shows the ether dome; B.
Central tube removed from apparatus]
(1) Closed Ether.
The two inhalers originally brought out for this were Clover’s in
London, and Ormsby’s in Dublin. At a later date Hewitt’s “wide bore”
modification of the Clover was introduced.
(_a_) _The Clover instrument_ (see Fig. 23)[4] consists of a
face-piece, a dome-shaped ether chamber, and a one-gallon bag, usually
attached to the top of the ether chamber by a =T=-shaped tube. The
details of the method by which the amount of ether inhaled by the
patient is graduated are best appreciated by unscrewing the milled
head at the top of the dome, and withdrawing the tube which runs
through it (_see_ Fig. 24). In the tube will be found two slots, one
about half an inch above the other, and each extending for half the
circumference of the tube. Between these two slots the tube is divided
by a diaphragm. In any case, therefore, air passing up or down the tube
must pass in and out of these slots.
Now turn to the tubular space left in the dome piece, and examine
visually and with the finger its interior. On the one side of its
middle will be found two slots leading into the circular ether chamber
which occupies a large part of the dome. On the other side will be
found a small cavity, as deep from above downwards as the two slots
combined, but _not_ communicating with the ether chamber. It is obvious
that with the tube inside, if this cavity is opposite the slots in
the tube, air will pass up the tube out of one slot and back into the
other, without coming into contact with the ether at all. If on the
other hand the slots in the tube are opposite the slots in the ether
chamber, the air passes over the surface of the contained ether, and
volatises some of it.
Intermediate positions of the tube give a condition where part only
of the air passes over the ether. The indicator attached to the tube,
combined with the figuring “O, one, two, three, full,” to be found
on the outside of the base of the dome, shows at any moment what
proportion of the air is passing into the ether chamber.
To use the instrument, fill the metal measure provided with ether,
withdraw the stopper from the ether chamber, and pour in the ounce
and a half of ether which the measure contains. Replace the stopper,
and blow through the tube to expel any ether vapour which may have
appeared in it. Leave the rubber bag at first unattached: the patient
will feel more comfortable if during the first minute the top of the
tube is open. With the indicator at 0 adapt the face-piece to the face
and allow the patient to breathe up and down the tube. By rotating
the dome, ether is then gradually turned on, until the figure two
is reached in the first minute. The indicator is then slipped back
nearly to zero for a second, and the rubber bag slipped on during
an _expiration_: it must be moderately inflated to supply the
requisite volume of air for respiration.
[Illustration: FIG. 25.--Hewitt’s wide-bore ether
inhaler.]
The rotation of the dome is again begun and the indicator is made to
travel away from the zero, until at the end of about five minutes, it
reaches “full.” After the first few minutes, it will be necessary to
give an occasional breath of fresh air, otherwise an undesirable degree
of cyanosis will result, but it must be done with great discretion, or
struggling will ensue. At the end of about five minutes, anæsthesia
should be fully established. A little extra ether is then poured
into the chamber, the indicator pushed back to about “two” and the
administration continued. One breath of fresh air is given in every
three or four. Spells may be given with the bag off altogether, but
during such periods the indicator will require to be advanced a little,
and refills of ether provided more frequently than would be necessary
if the bag were on.
Hewitt’s-wide-bore.
The principle of this is identical with that of the Clover, but the
channels being wider, there is less mechanical interference with the
ingress and egress of air. The actual construction differs also, in
that to turn on the ether, instead of rotating the dome, one moves the
indicator (_see_ Fig. 25). The instrument certainly gives results
a little better than those obtainable by the Clover, but it is heavier,
and rather more bulky.
Ormsby’s Inhaler (_See_ Fig. 26).
This consists of a facepiece, a cage made of wire or thin steel slips
and containing a sponge; and lastly, a one gallon bag which fits
over the cage. In the face-piece is an air vent, which can be either
entirely closed, partially or entirely opened.
[Illustration: FIG. 26.--Ormsby’s Inhaler. The cage
for the sponge does not show in the figure, it projects
upwards from the bag-mount, and is therefore enclosed in the
bag.]
To use the instrument, take out the sponge and warm it either by
wringing it out of hot water, or better by leaving it a few minutes on
the top of a hot steriliser. Push it back into the cage, open the air
vent fully, and holding the inhaler upside down, pour on to the sponge
a measure full (about half an ounce) of ether. Tell the patient to
inhale deeply, and then catch the resulting expiration in the bag by
quickly adapting the facepiece to the face at the appropriate second.
After a few seconds, begin to close the air vent, when it will be
found that the bag begins to wax and wane with each expiration and
inspiration respectively. After the first three minutes, the inhaler
must be removed, more ether poured in, the air vent opened again
partially, and the inhaler again applied to the face. After full
anæsthesia is induced, the air vent may constantly be left partially
open.
_N.B._--It must be observed that the air vent is not valved: it is
merely an opening through which part of the respired air may pass in
and out without going near the ether sponge.
In actual practice, the induction stage of closed ether is almost
invariably assisted by using either nitrous oxide, or a small dose of
ethyl chloride as a preliminary: these methods are described in Chapter
XV.
The question now arises, what _scope_ is to be assigned in modern
anæsthesia, to closed-ether methods. Formerly a large proportion of
anæsthesias, long or short, were conducted by the closed method, and
while the greater number of anæsthetists no longer utilise them to the
same extent as formerly, they may still be regarded as of the utmost
value in a limited class of cases. They are speedy in action, powerful
enough to overcome the most refractory patient, and with reasonable
skill very safe. On the other hand, the anæsthesia obtained is not
of the most desirable type. There is a great deal of salivation and
mucous secretion from the respiratory mucous membranes; the respiratory
movements are deeper than in open methods, from the excess of CO_{2}
present in the blood, and this leads to a good deal of heaving of
the abdominal wall, which may be most troublesome to the surgeon
if he is opening or closing that cavity. Moreover, after their use
more headache, malaise, and vomiting occur than after open-ether, and
perhaps a little more tendency to bronchitis or pneumonia. For these
reasons, many anæsthetists and surgeons now object to their use in
abdominal surgery, though some still adhere to them for the induction
stage, passing to the open method when the patient is once well under.
(2) Open Ether.
As already explained the strictly accurate term for this is
Perhalational Ether, but so cumbersome a terminology stands small
chance of general acceptance.
Apparatus.
The essential points in a proper outfit have already been explained
(_see_ page 28) and are all well met by the mask and ether dropper
introduced by Mr Bellamy Gardner (_see_ Fig. 27). The mask is covered
with from twelve to sixteen layers of gauze, and lies on the gauze
ring, shown in the Fig. 28A, which completes the fit between face and
facepiece. The dropper fits into the ordinary six ounce dispensary
bottle: the long arm dips into the ether, the short one allows air
to enter the bottle to replace the ether used. A dropper can also be
improvised by using a cork with slots cut at each side and with
a gauze or wool wick inserted along one of these. The author finds
these uncertain in their action, however: with Gardner’s dropper, a
steady flow of _drops_ of ether slow or fast as required, can always be
obtained once the student has acquired the knack of using the appliance.
[Illustration: FIG. 27.--Bellamy Gardner’s (A) open ether
mask; (B) ether dropper.]
[Illustration: FIG. 28.
_A._--Open ether. Ready to begin.
_B._--Open ether. Condensing towel in position.]
[Illustration: FIG. 28.
_C._--Open ether. Correct method of holding mouth and jaw.
_D._--Open ether. Alternative method of holding mask.
The towel and gauze have been removed so as to show the
tilting of the mask which this method is liable to cause.]
To Mr Bellamy Gardner’s outfit, the author adds a folded towel, pinned
at one corner, so as to form a short cone. The base of this cone
embraces the mask and face; through its upper apperture the anæsthetic
is dropped on to the mask. The cone can be rotated into the position
most convenient for this purpose in any given position of the patient’s
head (Fig. 28).
Problems of the Induction Period.
Open-ether is not a powerful anæsthetic, just not powerful enough for
one to be sure that one can induce full anæsthesia with it alone, in a
powerful subject. The reason for this is shown in Appendix II, and may
be here condensed by explaining that some 18 per cent. to 20 per cent.
of ether vapour is required to induce anæsthesia, while it is not easy
to get more than 14 per cent. off an open mask. How is this situation
to be met?
Reference has already been made to one solution of the problem. _A
closed ether method may be used for induction_, and this practice is
widely used. The author does not often adopt this course, fearing that
the undesirable features of closed ether may persist even after the
change to an open method has been made.
Another possibility even more widely favoured is to use _chloroform as
the inducing agent_, and only to turn to ether when full anæsthesia
is obtained. To this plan the author is strongly opposed. It exposes
the patient to the risks of the induction stage of chloroform which
are much greater than those of the later stages. Moreover, to develop
the full advantages of open-ether, a preliminary hypodermic of morphia
is essential, and the drawbacks of chloroform _plus_ morphia are
elsewhere mentioned (page 43).
The use of a _mixture of chloroform two parts, ether three parts_,
presents the same disadvantage, but in a degree so much smaller that
in powerful or alcoholic patients, the author believes this to be the
method of choice (_see_ Chapter xiv.).
_Dr Silk_ has recently suggested another plan. He has sought to make
open-ether easy for the non-expert with a view of encouraging the
wider use of so valuable a method. For this purpose he advocates the
admixture of one part of chloroform in thirty-two of ether (a dram of
chloroform in four ounces of ether). This is to be given in exactly the
same way as perhalational ether, and will, Silk says, give a type of
anæsthesia, and a degree of safety, identical with those of pure ether.
The author’s experience with Silk’s mixture is too limited to enable
him to offer any opinion upon its merits.
Lastly, there remains the plan of using _ether as the main inducing
agent_, but assisting its action by the intermittent and most guarded
addition of small quantities of C_{2}E_{3} mixture. This is the
author’s “stock” method; but in teaching it to students, too much
emphasis cannot be laid upon the small quantities of chloroform mixture
required or _permissible_. _As a consequence of the perhalational
method here advocated, every drop of chloroform which appears on the
mask will when volatilised, give a very much higher percentage of
CHCL_{3} vapour in the inspired air, than the same quantity exhibited
on the ordinary open chloroform mask._ Once the student has grasped
this essential fact, ordinary care and intelligence will enable him to
guard against a danger which is only existent if unappreciated.
The Administration.
For many of the hints given in this section the author is indebted to
Dr W. J. Ferguson of New York, and Dr Hornabrook of Melbourne.
Success in inducing with open-ether is attained only by attention to a
number of small details. The student who thinks that some of these are
too trifling for his notice is usually the man who informs you that
induction by open-ether is impossible, the fact really being that he
has not taken the trouble to learn, or has never had proper tuition.
The following are the points demanding attention:--
1. Always give a dose of morph-atropine or other narcotic, half
to three-quarters of an hour beforehand.
2. See that the patient is comfortable on the table. Prop up his
head and shoulders a little with pillows. In powerful subjects
Hornabrook tilts the whole table down at the foot-end, for a few
degrees.
3. Adhere strictly to perhalation and to the drop method. You
will never induce with open-ether if the whole volume of the
respired air does not pass through the gauze.
4. Chat to the patient as long as consciousness can possibly
persist. Tell him he is doing very well. Don’t shout complicated
instructions at him as to how to breathe: it annoys and muddles
him.
5. When the gauze ring and the mask are in position, allow one
or two drops of ether to fall on the mask, then pause: in a few
seconds the mild ether vapour so formed will soothe the upper
respiratory tract, and prepare it for the stronger vapours yet
to come. This does not waste time--it saves it.
6. When the administration is again begun, attend closely to
the rate of dropping. At first not more than one drop in three
or four seconds is wanted. The full rate of dropping cannot be
attained for at least ninety seconds.
7. Give no mixture for the first ninety seconds; thereafter some
five to ten drops every half minute or every twenty seconds
according to type of patient. Have the mixture bottle handy so
that no time is wasted in changing bottles. Stop the addition of
mixture as soon as full anæsthesia is attained.
8. Slip the folded towel over the mask and tuck its base well
round the chin and face. Do this only after the first two
minutes have elapsed.
9. As soon as the neck muscles are relaxed, turn the patient’s
head over to one side, and let the hands assume the position
described in Chapter iii. and illustrated in Fig. 28C.
10. The student is warned to discourage the too early attentions
of the nurse or house-surgeon. These officials are naturally
anxious to “get the patient ready for the Chief” and are
apt to start “cleaning up” before the patient has lost all
consciousness. A man who is doing his level best to go to sleep,
derives neither pleasure nor profit from a wholly unexpected dab
of ice-cold methylated spirit upon his umbilicus.
By the use of the method here advocated, induction is singularly easy
and successful in good subjects. The struggling stage is either not
represented at all, or appears only in the form of the lifting of
a limb and a slight occasional pause or catch in respiration. Full
anæsthesia is often announced audibly, by the commencement of a gentle
“blowing.” Once it is heard, the anæsthetist may rest assured that a
workable level of anæsthesia is either present or not far off.
Amounts of Ether required.
If the above instructions are followed, the amount of ether required
is not excessive. Anæsthesia is attained after the use of about 1½ to
2 ounces of ether and one or two drams of mixture. The next forty to
fifty minutes demand about another four or five ounces of ether; no
mixture at all. Some practice, is required before these small figures
are attained. The more practice, the less ether is required.
III.--VAPOUR ANÆSTHESIA.
In a sense, all forms of ether anæsthesia are vapour methods, but
in all the forms so far described, the patient has to vapourise the
drug for himself: in a true vapour anæsthesia this is done for him,
and the mixture of air and ether vapour propelled towards him. One
of the keenest advocates of this method is Dr Gwathmey, of New York.
He lays great stress also upon the necessity of warming the vapour,
claiming that this measure will prevent the loss of heat to the patient
incidental to the warming up in the air passages of the cold vapour
usually supplied by other methods; but the results of the laboratory
experiments upon which Gwathmey founded his case are inapplicable to
the human subject, in that they were performed upon dogs and cats,
which lose heat largely from the mouth and air stream. Man is not a
hairy animal, and transacts most of his thermolysis through the medium
of his skin. None the less, warming the vapour of ether has value since
the process removes some of the irritant effects so marked in the case
of cold ether vapour.
Apparatus for the Vapour Method.
In 1913, Karl Connell described such an apparatus, which was then in
use at the Roosevelt Hospital, New York. The ether was vapourised by
dropping it into a warm chamber. Air was pumped into the chamber, and
carried the ether vapour in known percentage, and at known pressure as
shown by gauges. Such mechanism is ideal, but would certainly be rather
costly. Its great value was that it informed us with certainty what
proportions of ether in the atmosphere were necessary to induce and
maintain anæsthesia (_see_ Appendix II.).
A simple mechanism was brought out shortly afterwards by Dr Shipway, of
Guy’s, and is known as Shipway’s warmed Ether.
It consists essentially of the following parts (_see_ Fig. 29):--
(1) A small hand bellows (B).
(2) An ether bottle, with tube for delivery of air stream
dipping deeply into the fluid: the exit tube of course does not
dip in. The bottle stands in a metal pan in which water at about
75° Fahr. is to be placed (E).
(3) A thermos flask (W) in which is a metal tube (U). The
etherised air passes along this tube, and picks up heat from its
walls. The thermos is filled with water at about 180° Fahr.
[Illustration: FIG. 29.--Shipway’s warmed ether vapour
apparatus.]
(4) A mask upon which a towel or gauze is to be stretched: the
rubber tube bringing the air and ether is brought through the
covering material and delivers the anæsthetic vapour in the
region of the mouth.
(5) Additional to the above, there may be added a small
chloroform bottle (C). In specimens of the instrument containing
this convenience, there has, of course, to be a regulating tap
(T) at the head of the ether bottle, which will divert more or
less of the air stream towards the chloroform.
This little machine, somewhat resembling a cruet stand in its
appearance was widely used in France. Owing to the kindness of
the Edinburgh Red Cross Committee, one was provided for the Base
Hospital with which the author proceeded to Salonika, where he used
it extensively. The impression of it formed by himself and others
was that it was peculiarly easy to maintain with it a steady level
of anæsthesia. It had, however, no claim to banish post-anæsthetic
bronchitis and pneumonia, of which in spite of much anxious care and
thought, a fair number of cases were seen during the winter time
(_see_ page 151).
In using the machine, it is necessary to remember that from the
physical point of view, one is providing from the machine a small part
only of the total volume of air required by the patient.
The bellows are quite small: one squeeze of the hand will not supply
more than about the equivalent in volume of one or two fluid ounces.
The larger part of the volume required by the patient has to be
obtained from the general atmosphere, so that the percentage of ether
which may be as high as 25 in the exit tube, will be greatly lowered by
the time it reaches the patient’s respiratory tract.
* * * * *
The actual strength of ether breathed by the patient will depend upon:--
1. The force and frequency with which the pump is compressed.
(_N.B._ It is of course useless to pump during expiration).
2. The depth of ether in the bottle.
3. The temperature of the water bath in which the ether bottle
stands. The warm water should only be put in at the last moment
before starting, otherwise very strong ether vapour will collect
on the surface of the ether, and the first puff of the bulb will
expel a highly irritant vapour towards the patient.
With specimens of this machine which have the addition of the
chloroform bottle, it is perfectly possible to conduct even the
induction stage of anæsthesia; a mere trace of chloroform vapour will
be sufficient. It is unnecessary to give detailed instructions for the
use of the machine. A preliminary consideration of the above physical
facts, together with a little cautious practice, will enable the
student rapidly to acquire facility with the method.
IV.--RECTAL ETHERISATION.
For such operations as the removal of jaw or tongue there are obvious
advantages in being able to introduce ether vapour to the blood per
rectum, since the mouth and air passages are thereby left free for the
attention of the surgeon.
Many years ago this was attempted by vapourising ether and propelling
the vapour through a tube high up into the rectum. This method was
abandoned, as it led to a good deal of inflammatory trouble afterwards.
Recently, Dr Gwathmey suggested a new method of utilising the rectal
route which has largely overcome this objection.
Gwathmey’s Oil Ether Method.
This consists in passing into the rectum a mixture of olive oil and
ether. The bowel is first carefully washed out, and an hour before
operation, the patient receives a hypodermic of morphia, gr. ⅙;
atropine, gr. ¹⁄₁₂₀. A suppository of chloretone gr. v is also passed
into the rectum to act as a local sedative. Half-an-hour later, the
patient is put into the left lateral position, a soft catheter
attached to a funnel is passed some six inches up the rectum, and the
mixture of oil and ether poured into the funnel. It is wise to take at
least five minutes to introduce the whole dose.
The following table shows the dosage required:--
+------------------+-------------+------------------------------------+
| | Strength of | |
| Age of Patient. | Ether in | Quantity of Mixture required. |
| | Mixture. | |
+------------------+-------------+------------------------------------+
| Under 6 years | 50% | One ounce to each 20 pounds body |
| | | weight (no preliminary morphia) |
| | | |
| 6 to 12 years | 55% to 65% | Do. do. |
| | | |
| 12 to 15 years | Do. | One ounce to each 20 pounds body |
| | | weight (but use ¹⁄₁₂ gr. morphia) |
| | | |
| 16 years and | 75% | One ounce to each 20 pounds body |
| upwards | | weight with ⅙ gr. morphia as a |
| | | preliminary |
+------------------+-------------+------------------------------------+
In practice then, for the ordinary adult, one uses eight ounces of the
mixture, six ounces of which are pure ether. The oil and ether require
to be shaken together, but remain blended long enough for introduction.
In five or ten minutes, the patient begins to feel a rather pleasing
numbness and tingling in the lower, and later the upper extremities,
and drops quietly to sleep in about twenty minutes. In a large
proportion of cases, it is necessary to deepen the anæsthesia by the
use of the open mask for a few minutes, but once a deep anæsthesia has
been thus obtained, the absorption from the rectum will balance the
loss in expiration and maintain a good anæsthesia for three quarters of
an hour at least.
On return to bed of the patient, the nurse passes two tubes placed side
by side, as high into the rectum as she can; the end of a Higginson
syringe is inserted into one of them, and a considerable quantity of
soap and water is pumped gently into the bowel, escaping down the
second tube. The washing must be continued until all smell of ether
is removed. Finally the soapy water itself is washed away by a little
saline.
Unless there be some pre-existing local inflammatory disease of the
rectum (in which case the method should not be used), there are no
unpleasant sequelæ after oil ether. The chief objection to the method
is the amount of labour thrown on the nursing staff, which is so
considerable as to bar it from adoption as a routine. This should not,
however, be allowed to prevent its use in the limited number of cases
in which it is strongly indicated. These are:--
(1) Panic-struck cases who cannot face the ordeal of ordinary
methods.
(2) Nose, throat, and tongue operations where intratracheal
ether is not available.