166
SECTION I
GENERAL SURGERY
CHAPTER VI
ANESTHESIA
The
problems presented l)y the wounded in their relation to anesthesia may
be grouped
(1) according to the general condition of the soldier and the length of
time between the receipt of
his injury and operation; or (2) according to the type of wound and the
part of the body injured. Thus, in the front line hospitals men still
suffering from shock or hemorrhage might require an immediate
operation, and even the lightly wounded, on account of exposure,
fatigue, cold,
possibly lung involvements, bronchitis in particular, would be but
little able to endure well the
dangers of an inhalation anesthetic. Under each of these varying,
conditions-at the front-line
station, the lightly wounded but exhausted soldier and the seriously
wounded soldier in shock;
and at the base hospital, the soldier who has arrived hours or days
after his injury was received in whom infection has mounted and even
gas gangrene may have developed-what is the
anesthetic method of choice, and does the part involved also influence
the choice of the
anesthetic?
During
the World War the choice of anesthesia lay among chloroform and ether
and
nitrous oxide-oxygen as general anesthetics, spinal anesthesia, and
block or regional anesthesia
or local anesthesia. In the first year of the European War the
paramount value of nitrous oxide
and oxygen anesthesia in operations upon the seriously wounded,
whatever their degree of
exhaustion, was demonstrated by American anesthetists attached to the
Western Reserve
University Unit in service at the American Ambulance at Neuilly,1 and one of the nurse
anesthetists, by the special request of the French and English medical
officers, remained in
France after the return of this unit to America to give instruction in
the technique of the
administration of this anesthetic.
The
extension of confidence in the value of nitrous oxide-oxygen in
military surgery was
attested by the conclusions adopted by the second session of the
Interallied Surgical Conference
held in Paris early in 1917, which was attended by delegates from
England, Belgium, France,
Italy, Japan, Portugal, and Serbia. In the various sections of these
conclusions appear the
following statements: 2
V. Treatment of gaseous
gangrene.-Anesthesia
by means of nitrous oxide with oxygen is considered the
best; when this is not to be had, ether may be substituted.
VI.
Traumatic shock.-Local anesthesia combined with general anesthesia by
means of nitrous oxide is the
best. Next to this ether appears to be the least harmful. Spinal
injections have produced varying results according to
the surgeons employing them, especially in amputations of the lower
limbs. The use of chloroform is dangerous.
VII. Amputations.-In the case of
serious shock, the use of nitrous oxide and oxygen is desirable; ether
is the
next best anesthetic. Only in the case of cerebral wounds is any other
anesthetic method advised.
XIV.
Cerebral wounds.-Local anesthesia is preferred for the operation. The
sitting posture tends to diminish
hemorrhage and is easily maintained in secondary or delayed operations.
167
At
a later meeting of the Interallied Surgical Conference, at which
delegates from the
United States and from Russia were present, as also from the countries
listed above, similar
conclusions were adopted.3
FIG.
98.-
Nitrous oxide manufacturing
plant. Captured German cylinders in foreground, converted for use in
nitrous
oxide service. One-half million gallons of nitrous oxide ready for
shipment to various American Army hospitals
When
the first base hospital unit of the United States Army to be called
into service (Base
Hospital No. 4, the Lakeside Unit) left for France it was
FIG. 99.- Storage building,
office, and
laboratory of nitrous
oxide manufacturing plant. Dimensions, 50 hy 75 feet, housing 700 tons
of ammonium nitrate
equipped with what then appeared would be an adequate supply of
nitrous oxide gas and
apparatus for its administration.4 During the
summer of
1917 the surgeons of this unit had
opportunities of testing the comparative value
168
FIG. 100.- Motors of 25 horsepower, used
to drive compressors
FIG. 101.-Detail of compressors. Each unit
was capable of
ompressing 10,000 gallons daily
FIG. 102- Partial view of retort
room.
Each retort was capable of producing 5,010 gallons per 8-hour run. The
retorts numbered 30
169
of nitrous oxide, of ether, and of spinal anesthesia att a base
hospital at Rouen (No. 9 General
Hospital, British Expeditionary Forces) and at British casualty
clearing stations in Flanders.5 Almost immediately inquiries
were made by both English and French officers as to the possibility of
securing an adequate supply of nitrous oxide, and it became evident
that the supply brought over by this unit would soon be exhausted and
the and the
English supply was
inadequate for their own needs. An immediate request was there
therefore sent to the American
Red Cross at home, and the matter was taken up with the Red Cross
representatives in France,
with the result that the American Red Cross appropriated funds for the
purpose.6
FIG.
103.- Drip bottles and
wash
bottles which were connected with the retorts shown in Figure 102
With the funds
so secured a plant was manufactured. It had a capacity
of 125,000 gallons per eight-hour operation and was the largest in the
world at the time of its construction. It was completed, tested,
approved, and shipped from Cleveland early in January, 1918; but, owing
to
the exigencies of transport, the shipment was lost track of after it
left New York and did not
reach its destination in France until May 30, 1918. No further time was
lost, however. Several
men trained in the manufacture of gas, who had been released from the
home plant to take charge of the assembling and operation of the plant
in France, within six weeks-two weeks less than the estimated time for
erection-had the plant ready for operation. Unfotunately, there was
FIG 104.- Military balloon,
used to store gas. This took
the
place of the usual steel
gasometers.
170
again a brief delay due to a shortage of cylinders, but this was
soon overcome by the acquisition
of a number of captured German cylinders which were converted for our
use. The plant was then
in continuous operation until about the first of January, 1919, and
thereafter continued to operate
intermittently for about three months, after which it was taken over by
the Salvage Corps.
CRITERIA
FOR THE CHOICE OF METHOD
Before indicating the choice of anesthetic method in
different
types of cases it may be
well to give here the evidence upon which the assertion is based that
nitrous oxide-oxygen in the
hands of a skilled anesthetist is the anesthetic of choice for the
wounded soldier, in particular for
the soldier in shock or exhaustion.
As
has been stated above, the choice of anesthetic lies among the
inhalation anesthetics,
the lipoid solvents, ether and chloroform, and nitrous oxide-oxygen,
and the various agents
employed in spinal, regional, or local anesthesia. In making a choice
we must know (a) what
damage, if any, is caused by the anesthetic per se; and (b) what
protection, if any, is offered by
the anesthetic per se.
INHALATION ANESTHESIA
ETHER AND CHLOROFORM
In
normal animals and normal men inhalation anesthetics, chloroform and
ether more
markedly than nitrous oxide, cause increased hydrogen-ion concentration
of the blood-acidosis--during and roughly for about one hour after
anesthesia. Protracted ether or chloroform anesthesia
causes cytologic changes in the cells of the brain, the liver, and the
adrenals identical with those
resulting from other causes of exhaustion. After from four to six hours
of continuous ether
anesthesia many animals die; some never regain consciousness, but die
within the first 24 hours.
In the extensive studies of shock, hemorrhage, and gas infection made
(by Lieut. Col. W. B.
Cannon, M. C., and his coworkers7) at the Central Medical
Department Laboratory, A. E. F., at
Dijon, France, which have been continued in the laboratories of
physiology of the Harvard
Medical School,8 it was found that "the administration of
ether, from
its very beginning, results
in a depression of the heart and a decrease in its output, which is
sufficient to account for the fall
in pressure in both the normal and the shocked animals"; that in normal
animals "the inhalation
of strong ether results in a sudden drop in the arterial pressure which
is quite temporary"; while
"in the shocked animal there is no recovery of the blood pressure after
the primary fall and the
pressure continues to fall to zero even before the eye reflex
disappears." In contradistinction to
the above observations these investigators found that "nitrous oxide
and
oxygen, in the most
favorable proportions, can be administered to the shocked animal
without causing more than a
slight drop in blood pressure." They state, further, that "The
condition of ether sensitiveness is
brought about by any circumstances which tend to depress the general
condition of the animal
such as low blood pressure, hemorrhage, severe operations, or the
injection of acid into the
circulation"--a conclusion of immediate and vital significance in its
relation to the choice of
anesthetic for the wounded soldier.
171
Ether
and chloroform actively contribute to shock and exhaustion. They should
be given
evenly and lightly, therefore, as by the excellent Shipway apparatus,
which is undoubtedly
superior to the open-drop method. Marshall has shown that patients may
apparently do well
during ether anesthesia but
CHART
I.- The effect of
intravenous
ether on the pulse and blood pressure. (By courtesy of
Capt. Geoffrey
Marshall, R. A. M. C.)
do badly afterwards; but that they do well both during and after
nitrous oxide-oxygen anesthesia.9 From the patient's
viewpoint, nitrous oxide-oxygen is the
choice.
NITROUS OXIDE-OXYGEN
Nitrous
oxide-oxygen anesthesia is light and gives less muscular relaxation
than ether or
chloroform. Special training in its administration is absolutely
172
required, for it is technically the most difficult of all
anesthetics to administer safely, although its
administration is facilitated by recent improvements in the apparatus.
These disadvantages,
however, are far outweighed by its advantages as compared with ether or
chloroform. It is quick
in its action; is pleasant to take; recovery is immediate; it produces
no nausea; it is protective,
strongly protective against the shock of operation; for many minor
operations it produces a
pleasant analgesia in which pain is abolished while consciousness is
retained; it can be given
under positive pressure when desired, as
CHART II.- Comparative effects
of ether and
nitrous oxide in
thigh amputations, as indicated by
the pulse and blood pressure. (By courtesy of Capt. Geoffrey Marshall,
R. A. M. C.)
in chest operations, maintaining the lung flabbily in the chest
against the chestwall. or protruding
out of the opening in the chest wall, as may be required.
In
the surgery of the front area its quick action, its protective effect,
the fact that it caused
neither bronchitis, pneumonia nor nephritis, and that the patients
recovered quickly so that they
could eat and drink and travel soon after operation, and required less
nursing care--all made
nitrous oxide-oxygen the anesthetic of choice not only for routine
operations, revising wounds,
opening abscesses, etc., but especially for painful dressings, as it
could be used repeatedly
without harm. In the case of one patient in civil practice, Gwathmey
173
mey has give nitrous oxide-oxygen 118 times; neither tolerance nor
dread was established.10
Nitrous oxide, like ether and chloroform, must be
pure.
The apparatus for its
administration must be capable of delivering any desired pressure and
mixture of nitrous oxide
and oxygen. The induction of anesthesia must be gradual, not too rapid;
and respiration must be
established and maintained at an even rate. The patient must be kept
pink throughout the
anesthesia. The pink patient can not die. If complete anesthesia can
not be sured, as in
alcoholics, and the patient kep pink, or if anesthesia is attained, but
sufficient relaxation can not
be secured and the patient kept pink by nitrous oxide-oxygen alone,
then sufficient either must be
added.
As
for the technique of its administration, the following points may be
noted: (1) In long
operations, the fixation of the anesthetic mask with a towel fastened
with forceps relieves the
fatigue of holding the mask. (2) If induction is slow or difficult, a
few whiffs of ether help to
smooth out the respiration. (3) In abdominal cases local anesthesia is
useful, and during
exploration ether should be added. (4) Young, robust patients are most
difficult subjects-the
weaker the patient the easier the anesthesia. (5) In acute hemorrhage,
the absence of pink color
may make it more difficult to appreciate the depth of anesthesia so
that the respiration must be
closely watched. (6) Because nitrous oxide-oxygen anesthesia is more
difficult to give, costs
more, and requires more expensive apparatus than ether, this anesthetic
seems less satisfactory to
the operator; but because its protection is so great, its inhalation so
pleasant, its after effects so
slight, it must be regarded as strictly the patient's anesthetic.
SPINAL ANESTHESIA
Marshall's 9 observations have shown that one of the immediate effects
of spinal
anesthesia is the fall in blood pressure (Chart III). This has been
conclusively shown in laboratory
experiments on animals. Marshall has shown that the fall in blood
pressure is most severe in the
patient whose blood is dilute--his hemoglobin low--the patient most in
need of the protection of
nerve blocking. In both laboratory and clinic it has been shown that no
amount of trauma upon an
area physiologically severed from the brain by a local anesthetic, by
blocking the spinal cord or
the nerve trunks, or by local infiltration, can cause shock. In this
manner, as far at least as trauma
is concerned, a shockless operation may be performed, but the sights
and the sounds of the
operating room; the patient's knowledge that his flesh is being divided
by a knife; that his blood
vessels are being divided and tied; the sound of the saw that severs
his bones; all these contribute
to psychic shock. Moreover, in a rush period the delay of spinal
anesthesia does injustice to
patients waiting for operation when anaerobic contamination so promptly
becomes gas gangrene.
Spinal anesthesia is therefore of value in all but rush periods,
provided that the consequent great
fall in blood pressure may be prevented and that the psychic factor may
be eliminated.
As
has been shown in the laboratory and confirmed in the clinic. the
transfusion of blood
stabilizes the circulation to the following extent: In animals that are
overtransfused so that the
blood pressure rises higher than the normal
174
blood pressure, the elasticity in the blood vessels provides a
substitute for the peripheral
resistance produced by the action of the vasomotor center and in
consequence the blood pressure
is independent of the nervous system and behaves as if it were
controlled by a system of rubber
tubes. After overtransfusion, therefore, spinal anesthesia, the
destruction of the medulla and the
cord, or even decapitation, cause no fall in the blood pressure,
because the entire vascular system is not onlv filled but elastically
distended with blood. This overdistention
CHART III.- Effect of special
anesthesia or, pulse and
blood
pressure. (By courtesy of Capt.
Geoffrey Marshall, R. A. M. C.)
lasts for one or two days. Therefore, in a case of profound
exhaustion, if an ordinary transfusion
of blood be given first, then spinal anesthesia may cause no serious
fill in blood pressure. The
other damaging factor, the physic factor, may be largely overcome by
morphine, but still better
by nitrous oxide analgesia, by very light nitrous oxide-oxygen
anesthesia, or by light partial ether
anesthesia-just enough anesthesia to eliminate psychic appreciation of
the operation, room and
the operation itself.
175
Cabot
made a special investigation of the value of spinal anesthesia in thigh
amputations,
regarding which he makes the following statement:
The mortality of thigh amputations for shell
wounds under chloroform or ether anes-thesia was uniformly
close to 40 percent in a series of somewhat over 100 cases, this
during the battles on the Somme and the early
fighting in 1917, particularly at Vimy Ridge. As a result of this
experience, I gave orders that all thigh amputations
should be done under spinal anesthesia and detailed an officer to
handle the anesthetic. In 50 consecutive cases under
this technic the mortality was just under 25 per cent. At the end of
this series we stopped, on account of press of
work, keeping any special records, and, therefore, the observation is
only on a small scale, but seems to me of
definite value. We had no opportunity of comparing the effects of ether
and chloroform with nitrous oxide. It is my
own opinion that nitrous oxide would have made a better showing than
ether or chloroform.
One
of the strongest advocates of spinal anesthesia was Desplas, who
summarized its
advantages as follows: 12
(1) No special anesthetist is needed.
(2) Under spinal
anesthesia any special treatment
necessitated by the shocked condition of the patient may be easily
given. (3) The possibility of
pulmonary, renal, or hepatic complications such as result from general
anesthesia are excluded.
(4) There is no postoperative vomiting. (5) By spinal anesthesia
complete relaxation of the
muscles is obtained as under no other anesthesia. This condition is
especially helpful in: (a)
Extensive laparotomies, as the intestinal mass has no tendency to
protrude and shock due to
malaxation is thus, ipso facto, almost nonexistant. (b) Operations for
extensive shattering of the
lower members.
Desplas
added that patients who have experienced both methods prefer spinal
anesthesia.
As was
emphasized by Rocher,13 spinal anesthesia was of especial
value incases in which lesions
in the air passages rendered inhalation anesthesia inadvisable, and
also when the nature of the
wound would require the maintenance of the prone position.
LOCAL ANESTHESIA
In
the exigencies of war surgery, especially in rush periods at the front
when apparatus for
the administration of nitrous oxide-oxygen may not be available and the
prolonged periods of
induction and of recovery from ether or chloroform are not feasible,
increased reliance must be
placed upon regional or local anesthesia in combination with morphine.
For the excision of
contused tissues, for the removal of debris, for probing in soft
tissues for missiles, for the
amputation of fingers, for the repair of scalp wounds, local anesthesia
may in many instances be
preferable to the general anesthetic even when the latter is available;
and, as indicated above in
the cited conclusions of the Interallied Surgical Conference,2 local anesthesia is the anesthetic
method of choice for the repair of cerebral wounds. Certainly
these operations can be accomplished under local anesthesia with a
minimum
expenditure of time as well as with minimum discomfort to the patient.
It should be borne in
mind, however, that local anesthesia may decrease the resistance of
tissues which are already
contaminated.
ANALGESIA
In
certain cases either the time factor or the exhaustion of the patient
may make it
advisable not to carry the anesthetic beyond the stage of analgesia.
The former factor may be
dominant in cases not suitable for the employment of
176
a local anesthetic, as when vascular regions important organs are
involved or wide retraction is
required, or the second factor may be dominant in cases in which
exhaustion from exposure,
from hemorrhage, or infection has so impaired the internal respiration
of the cells as to make the
induction of complete surgical anesthesia menacing. An attempt to meet
this problem wits made
by Gwathmev and Karsner,14 who made a study of the effects
of the oral administration of
various combinations of anesthetics, in particular of ether and
chloroform combined with liquid
petrolatum. In addition to experiments on animals a clinical
application of this method was made
on a group of soldiers in Base Hospital No. U. S. A. in service at No.
9 General Hospital B. E. F.,
and later by Captain Gwathmey at a casualty clearing station.
The
safest method of analgesia is that induced by nitrous oxide-oxygen;
when this is not
available, the combination of morphine with local anesthesia or with
nerve blocking provides the
maximum protection.
ADJUVANT MEDICATION
MORPHINE
Morphine
has possibilities for good and for evil which are not yet fully
appreciated.
Laboratory researches have confirmed what clinicians have experienced,
viz, that morphine
diminishes shock, prolongs life in precarious situations, such as deep
hemorrhage, shock,
infection; that, under morphine, patients require less food and the
temperature and pulse in
infections are materially controlled; that under such circumstances the
morphine habit is not
formed. Clinical experience shows, further, that morphine does harm
when patients are cyanosed.
Researches have shown that when large doses of morphine are given to
animals under deep
anesthesia or in acute cyanosed exhaustion from intense exertion, they
are deprived of the power
to overcome the cyanosis, i. e., the acute acidosis. Therefore,
cyanosed patients should never
have morphine.
While
morphine never causes a habit when given in these extremely critical
states, it
easily establishes a habit when given in cases of psychic distress, in
worry, insomnia, etc. There
is opportunity for wide discrimination in its use-in one case, none
should be given; in another
case, light doses may be beneficial; in other cases massive doses are
most useful. When the way
is clear so that massive doses of morphine may be given safely, it is a
most potent agent. In the
surgery of war it was of paramount value when used as an adjuvant to
general or local anesthesia.
MAGNESIUM SALTS
In
the laboratory it has been found that to a limited extent the
intravenous administration of magnesium salts is apparently a strong
agent in promoting intracellular restoration.
Intravenous infusions of magnesium salts lower the respiratory rate,
and induce a state
resembling sleep. This magnesium "sleep"lasts approximately two hours.
The good effects of the
infusion are well sustained. Not only are the clinical results
apparently good, but a study of the
effect upon the cytologic changes in the liver cells in exhaustion
shows a diminution of the
edema, not as marked but similar to that resulting from normal
177
sleep. It is possible, therefore, that the magnesium salts partially
exert the effect of sleep in aiding
cellular repair; hut the magnesium salts alone, in good dosage, are
cardiac depressants. Their use
is under observation, their value not established.
METHODS IN SPECIAL GROUPS OF CASES
As
stated at the beginning of this chapter, in discussing the anesthetic
method of choice in
special groups of cases it is impossible entirely to separate the
anesthetic from the other factors of
the operative management. It is obvious that in the case of the wounded
soldier, as of the civilian
patient, the management of the operation implies the closest
cooperation between the surgeon
and the anesthetist. For this reason, in the following summary the
operative factors which war
experience demonstrated to be of primary importance, are included with
the discussion of the
anesthetic method of choice in each case.
SHOCK AND EXHAUSTION
Among
the memoranda issued from the Division of Laboratories, A. E. F. those
relating
to traumatic shock and hemorrhage contain the following statements
regarding anesthesia.15
Clinical
observations have shown that after the body has been damaged by a shock
Blood pressure there is great sensitiveness to ether and chloroform
anesthesia. Experimental tests have proved that a degree of anesthesia
which abolishes in a shocked animal the simple reflexes may cause the
arterial pressures to fall rapidly 20 mm. of mercury or more. In a
series of
human cases the fall of pressure during operation averaged 30 mm. of
mercury--a disastrous drop
in view of the already existing low pressure. There arc two ways of
avoiding this harmful
change--by use of nitrous oxide and oxygen as an anesthetic and by
sustaining the pressure if ether
is employed.
Clinical and experimental observations have
demonstrated that if anesthesia with Nitrous oxide and
oxygen is properly produced a shock blood pressure need not be lowered
at all during the course of operation.
Preoperative administration of morphine should bet followed by expert
use of nitrous oxide and oxygen in the
ratio of not more than 3 parts nitrous oxide to 1 part oxygen. A higher
ratio may cause as great a fall of pressure
as is produced by ether. Deep anesthesia and cyanosis are to be avoided
at all times. The surgeon must adjust
himself to this light anesthesia, and its consequent absence of
complete relaxation, by patience and gentleness and by
a larger operative incision when necessary.
If
nitrous oxide and oxygen are not available, ether given by the drop or
vapor method should be
employed. As soon as the anesthetic is started, however, a blood
transfusion or an infusion of gum-salt solution
should be started and allowed to continue slowly. The head of arterial
pressure is thus maintained and may even be
raised during the period when it otherwise would be much lowered.
Chloroform
and ethyl chloride, which are even more depressant to the circulation
than ether, are to be
employed only when no other means of producing anesthesia is
obtainable. The foregoing directions are
approved by the Chief Consultant in Surgery of the American
Expeditionary Forces.
In
brief it may be stated that for the soldier in shock or exhaustion,
whatever the nature of
the wound, the primary requisites are physiologic rest, fluids by every
possible route-by mouth,
by hypodermoclysis, by intravenous Injections-elevation of the foot of
the bed; morphine if there
is no cyanosis; transfusion of blood; quick, deft, light operation. The
anesthetic of choice, as
has been sufficiently indicated above, is nitrous oxide-oxygen
analgesia combined if possible
with local or regional anesthesia.
178
ABDOMINAL OPERATIONS
If nitrous oxide-oxygen is used and it is the
anesthetic of
choice, regional infiltration with
novocain should be employed also to promote relaxation of the abdominal
muscles. If relaxation
is not complete then ether should be added but only during the
exploration.
If
ether is employed Gwathmey's warmed vapor technique, combined with
local
infiltration, is the best method of induction.16
As
Marshall has emphasized, the patient should be turned from side to side
as little as
possible during operation. The abdomen should be kept open the
CHART
IV.-
Comparative effects of
ether and or nitrous oxide in operations for the repair of extensive
abdominal
wounds. Note the greater extent of the trauma in the second case, which
received nitrous oxide. (By courtesy of
Capt. (Goeffrey Marshall, R. A. M. C.
least possible, length of time. Manipulations and exposure of the
viscera should be reduced to a
minimum; therefore, an ample incision should be made.9 If
the patient is in deep shock, a
transfusion of blood should be given at the beginning, and again at the
close of the operation.
OPERATIONS ON THE CHEST
An
extensive research was carried out by Gwathmey and his associates at
the Central
Medical Department Laboratory, A. E. F., at Dijons, France, for the
purpose of determining the
anesthetic method of choice.17 The findings in this study
were in
accord with the clinical
experience of Marshall, of the
179
writer, and of others, that nitrous oxide-oxygen under positive
pressure is the method of choice. The following statements regarding
the anesthesia in chest surgery were made by Lockwood: 18
Paravertebral anesthesia is administered two
or three spaces above and below the wound. A local
infiltration at some distance from the wound is employed.
Novocain
5 percent and potassium sulphate 0.25 percent in normal saline,
prepared fresh and repeatedly
autoclaved is injected with a Gray's syringe (10 mms. of adrenalin per
ounce are added just before use). Gas and
oxygen should be available for administration while the hand is inside
the chest or when the patient is restless.
The
most serious cases may be operated on with a light nitrous oxide
analgesia. Local anesthesia combined
with gas and oxygen is the best means of preventing shock in extended
operations. Neither ether nor chloroform
should be used in chest surgery.
An
official report on intrathoracic surgery contains the following section
on anesthesia:19
A simple method of giving nitrous oxide and
oxygen, utilizing tank pressure, to secure needed degree of
inflation, was devised by Captain Gwathmey. A full preoperative dose of
morphine made possible the induction of
deep analgesia, without increasing the nitrous oxide and oxygen rates
above 3 to 1, which Lieutenant Colonel
Cannon s experiments had proved to be the limit of safety in the presence of shock.
Lieutenant Cattell's observations
had indicated that morphine thus given had value as a prophylactic
agent against oncoming shock and therapeutic
value when given early in the presence of shock. No untoward result from depression of
the respiratory centre was
noted.
Animal experiments showed clearly that
administering anesthesia under tension, particularly when the chest
was opened, was dangerous if the gas or ether was given in increased
concentration. It also demonstrated that
thoracotomy with all incidental manipulations, such as dislocation and
operation upon lungs, should be performed
under the primary stage of anesthesia. Manometric observations showed
that when the pressure present in the mixing
bag reached 8-16 mm. Hg. it sufficed to distend the lungs completely;
that degree of pressure is present when the bag
fluctuated little during inspiration. Since this degree of tension in
the bag produced an intrapulmonary pressure that
was well within the limits of safety for dogs, the manometer was not
deemed a necessary adjunct for human use.
A safe sequence in practice was found to be as follows:
After the effect
of the preoperative hypodermic of
morphine was present, administrations of pure oxygen under no tension
were started. Then very gradually the
pressure was increased, and the administration of nitrous oxide
started. Rapid induction of the anesthesia was
undesirable. Avoidance of excitation and the producing of gradually
increasing inflation were essential. During the
operation the proportions of the gas-oxygen mixture and the pressure
transmitted to the trachea were varied to meet
conditions . After the parietal pleura was closed the amount of nitrous
oxide was gradually reduced; last of all,
oxygen under pressure was continued until the patient was conscious.
The
American Red Cross nitrous oxide apparatus, perfected by Captain
Gwathmey and
adopted by the Army, fulfilled every requirement. This apparatus
provides a mask that can be
rendered relatively air-tight by close approximation to the face, an
escape valve, a mixing bag
close to the inhaler, and a rough gauge for estimating the proportion
of the gases.
Intrapulmonary
pressure was raise by increasing the rapidity of the flow of gases
from
the tank and by increasing the pressure upon the face piece. It was
lowered by decreasing the rate
of flow of the gases or by releasing the valve or decreasing the
pressure which held the face piece
in place. Thus, any degree of desirable inflation or deflation was
promptly available to meet
operative requirements. In general the degree of pressure utilized was
that test suited to the
animal or man under operation.
This
method gives all practical requirements for intrathoracic surgery
without necessitating deep anesthesia for the introduction of
intratracheal or
endopharyngeal tubes. Moreover,
its safety and ease of control has removed the chief obstacle to a
wider application of surgical
therapy.
180
On
the basis of his large experience in France and at the Walter Reed
Hospital since the
war, Keller makes the following statement: 20
Nitrous
oxide is, in my opinion, the anesthetic of choice in war-time general
surgery and
its general use in all formations from front to rear during the late
war was limited only by lack of
trained anesthetists and difficulty of transportation to some front
line formations. Its use is also
somewhat limited for mobile warfare such as during a rapid advance.
In chronic chest surgery nitrous oxide is absolutely
the
inhalation anesthetic of choice,
especially when combined with the Crile novocain block or paravertebral
block, which enables
the operator to do chest work without passing the stage of analgesia.
Nitrous
oxide used in the above manner has lowered the operative mortality in
the
chronic thoracic surgical derelicts to a degree not attainable with
other inhalation anesthetics.
It is of
interest to note also that in the section on chest surgery in a
questionnaire sent by the
Research Committee of the American Red Cross to base hospital staffs in
France the following
preferences as to the anesthetic were expressed: 21 Local
anesthesia if possible was
recommended by all. For general anesthesia, the stated first choice was
as follows: Gas oxygen,
18; ether, 9; warm ether, 3; chloroform, 2.
To
summarize, in intrathoracic surgery, if there is cyanosis, oxygen
should be given under
pressure with enough nitrous oxide for analgesia until the gray-blue
color or the ordinary
cyanosis gives place to a pink color. This will usually require from 10
to 15 minutes. When the
pink color has been restored the anesthetic may be deepened as
required. With the gas and
oxygen apparatus the lungs can be inflated under positive pressure,
cyanosis overcome and
anesthesia maintained; and under high pressure both anesthesia and
sufficient lung ventilation
can be maintained even when both sides of the thorax are widely and
simultaneously opened.
An adequate exposure should be made. Resecting a
rib is better than working in a cramped
space. The lungs and heart and pleura should be handled precisely and
gently. The patient should
be moved as little as possible, the chest closed air-tight. Oxygen
should be given under pressure
at intervals during the first 24 hours, as the condition of the patient
may indicate.
OPERATIONS ON THE EXTREMITIES
Nitrous
oxide-oxygen is the anesthetic of choice, but if it is not available
then low spinal anesthesia by
Cabot's method may be given, but in such a case it is necessary to be
prepared to give a blood transfusion to
overcome the low blood pressure which will be caused by the anesthetic.
When
dealing with fractures under anesthesia, no less than without
anesthesia, the limb should be orientated
and handled so skillfully that little or no crepitus will be felt. In
amputations the nerve trunks should be divided as
lightly as possible and the limb handled as little as possible. In
grave shock, if no nitrous oxide is available, low
spinal anesthesia by Cabot's method may be used and preparations made
to give blood transfusions to overcome the
lowered blood pressure caused by the anesthetic. Large wounds should be
covered and protected as much as
possible. (Chart V.) (See also Chart II.)
181
GASSED CASES
Oxygen
under pressure should be given first, with just sufficient nitrous
oxide to eliminate the worry due to
the mask and to the oxygen inhalation. After the pink color is
restored, light surgical anesthesia may be induced. The operation
should he short and deft. As required, oxygen under pressure should be
given during the post-operative period. In these cases if nitrous oxide
is not available, local, regional, or spinal anesthesia should be
employed rather than general anesthesia.
CHART
V. – Comparative effects of
either and nitrous oxide in thigh amputations as indicated by the pulse
and
blood pressure. (By courtesy of Capt. Geoffrey Marshall, R.A.M.C.)
In cases of
phosgene poisoning it should be borne in mind that phosgene poisons by
reason of its
interference with the passage of oxygen through the walls of the air
vesicles, thus producing
anoxemia. Cases of phosgene poisoning, as is indicated by the rapid
respiration, increased pulse
rate, cyanosis, loss of mental and muscular power, sweating, etc., are
in a state of acute acidosis--the same end effect as is produced by
prolonged inhalation anesthesia,
by exertion, fever,
emotion, shock, exhaustion, etc. Therefore, since the inhalation
anesthetics themselves cause
acidosis, their administration adds one acidosis to another; i. e., the
acidosis of anesthesia
intensifies the acidosis of phosgene asphyxia. Surgical shock also
produces a state of acidosis. The
182
acidosis of the surgical operation, therefore, if added to the acidosis
of the phosgene and the
acidosis of the anesthetic may kill the patient.
Therefore,
when an operation is required in a case of phosgene poisoning, it
should be
performed under local, regional, or spinal anesthesia, the patient
meanwhile being kept pink by
oxygen under pressure by means of the positive pressure mask of a
nitrous oxide apparatus or a
Haldane apparatus. If there is a phase of operation that can not be
controlled by local or regional
or spinal anesthesia, then one should give oxygen under pressure until
the patient has a pink
color, then switch to nitrous oxide for the briefest time required for
the operative move, then
switch back again to oxygen under pressure.
OPERATIONS IN THE PRESENCE OF ACUTE
INFECTIONS
While
narcotization with morphine is of value in all cases excepting in the
presence of
cyanosis, in the acute infections, as has been proved by experiment and
demonstrated repeatedly
in civilian and war hospitals, morphine is of paramount value. In
such cases, therefore, the first
requisite is deep narcotization with morphine, and if time permits the
subcutaneous infusion of
1,000 c.c. of normal saline solution before operation. Nitrous
oxide-oxygen analgesia should be
used, the stage of full anesthesia being induced only as the exigencies
of the operation demand.
The morphine narcotization and saline infusions should be continued
until the patient is safe.
CONSENSUS OF OPINION AMONG BASE HOSPITAL STAFFS
The
questionnaire already cited contained, as would be supposed, special
sections
regarding the value of different types of anesthetics. For details in
connection therewith consult
the appendix of this volume.
LIMITATIONS
OF DIFFERENT TYPES OF ANESTHESIA
The
problems presented by anesthesia in war surgery, as in civilian
surgery, are in effect
problems of limitations. Therefore, since in the exigencies of military
surgery the anesthetic
method of choice may not always be available, it is peculiarly
essential that the limitations of
each type of anesthetic be kept clearly in mind.
SPINAL ANESTHESIA
In
the low blood pressure of acute shock or hemorrhage the additional fall
due to spinal
anesthesia as a result of the interruption of so large an area of
vasomotor nerves may cause
dangerous, even fatal collapse. This may be pre-vented by blood
transfusion. The psychic factor
may be both distressing and damaging, but may be eliminated by very
light ether anesthesia.
Occasionally spinal anesthesia is incomplete. Such a failure must be
met by a general anesthetic.
NITROUS OXIDE
In abdominal operations muscular relaxation may not be complete under
nitrous oxide
anesthesia. The condition should be met by regional anesthesia of the
abdominal wall and by
light handling.
Nitrous
oxide is a light anesthetic, demanding of the surgeon a light deft
operative
technique. Nitrous oxide must be given only by experts; it is dangerous
in inexpert hands.
183
ETHER
Ether
tends to cause bronchopneunonia, especially in abdomninal operations
during the
winter. It diminishes, even temporarily abolishes, phagocytosis, and is
therefore unsuitable in
infections. There is a tendency to a fall in blood pressure after
operation; hence it is unsuitable in
shock. Ether causes a rather large diminution in the reserve alkalinity
of the blood.
THE ANESTHETIST
If, as has been demonstrated, nitrous oxide-oxygen
is the anesthetic method of choice in military surgery, then it is
essential that corps of anesthetists especially trained for its
administration should be available. Safest of anesthetics in expert
hands, nitrous oxide is the most unsafe in the hands of the inexpert.
Since in military surgery the majority of patients are already grave
risks on account of exposure, exhasustion, and infection, it is
peculiarly necessary that the anesthesia should be handled by trained
hands.
REFERENCES
(1) Burlingame, C. C. Lt. Col.:
Military History of the American Red Cross in France, 135. On file,
Historical
Division, S. G. O.
(2) Conclusions adoptées par la
Conference Chirurgicale Interalliée, 1st Session, 15th and 16th March,
1917. Archives de médecine et de pharmacie militaires, Paris, 1917
1xvii, 531.
(3) Bid., 2d Session, 14th to l9th May,
1917, lxviii, 451.
(4) Letter from Major Harry L.
Gilchrist, M. C., to The Adjutant General, May 8, 1917. Subject:
Departure of
Base Hospital No. 4. On file, Record Room, S. G. O., 159444 (Old Files).
(5) Burlingame, op. cit., 137.
(6) Red Cross Reports on Nitrous
Oxide and Oxygen Service. On file, Historical Division, S. G. O.
(7) Cannon, W. B.: Acidosis in Case
of Shock, Hemorrhage, and Gas Infection. Journal of the American
Medical
Association, Chicago, 1918, lxx, No. 8, 531.
(8) Cattell, McKeen. Studies in
Experimental Traumatic Shock. VI. The Action of Ether on the
Circulation in
Traumatic Shock. Archives of Surgery, Chicago, 1923, vi, No. 1,
41.
(9) Marshall, Geoffrey. Anesthetics
at a Casualty Clearing Station. American
Journal of Surgery, Anesthesia
Supplement, New York, 1918, xxxii, No. 4, 61.
(10) Gwathmey, James T.: Personal
communication.
(11) Cabot, Hugh: Personal
communication.
(12) Desplas: Spinal Anesthesia. Medical
Bulletin, Red Cross Research Society Reports. Paris, 1918, No. 6,
447.
13) Roclher, H. L.: La
rachi-anesthésie en chirurgie de guerre. Journal de médecine de Bordeaux,
1919, xc,
ni.s., No. 1, 5.
(14) Gwathmey, James T. and Karsner,
H. T.,: General Analgesia by Oral Administration. British Medical
Journal, London, March 2, 1918, i, 254.
(15) Surgery in Relation to Shock. War
Medicine, Paris, 1918, ii, No. 5, 785.
(16) Gwathmey, James T.: Anesthesia.
The Macmillan Company, New York, 1924. 153.
(17) Ibid., 692.
(18) Lockwood, A. L. Early Operative
Treatment in Chest Surgery. War
Medicine, Paris, 1918, ii, No. 1, 7.184
(19) Official Report from Laboratory
of Surgical Research, Central Medical Department Laboratory, A. E. F.,
to
Brig. Gen. J. M. T. Finney, M. C., Chief Consultant in Surgery, A. E.
F. Subject: Intrathoracic Surgery (Anesthesia). War Medicine Paris, 1919, ii, No. 6, 1008.
(20) Keller, Win. L., Lt. Col., M.
C.: Personal communication.
(21) Compilation of Responses by Base
Hospital Staffs to Questionnaire sent out by Research Committee.
Questionnaire prepared by Brigadier General J. M. T. Finney and Colonel
G. W. Crile; Compilation of Responses made by Major T. W. Burnett, M. C. War Medicine, Paris, 1919, ii, No. 7, 1281.
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