For the immediate preparation of the patient it is advisable that the bowels should be moved the day before operation, that no food be administered for at least six hours previously, and fluids only for some hours prior to this.
The patient should be placed on a suitable narrow table in such a position that the light falls well into the mouth. Where practicable, a graduated head piece capable of being raised and lowered, in order at one time to throw the light on the soft, and at another on the hard palate, is desirable; but in private houses this is usually attained by a due adjustment of pillows. To prevent any sudden movement on the part of the patient the hands should be fixed to the side, and my usual method of accomplishing this is to pass a leather strap around the thighs immediately below the trochanters, and to this the wrists are attached by means of leather bracelets locking on to the circular strap by spring hooks. This plan of fixing the arms enables the patient to be turned from side to side to allow blood to pass out of the mouth when respiration becomes embarrassed by an accumulation in the pharynx. If the patient is strapped down to the table, this cannot be accomplished, and the plan just indicated will be found of great practical value. For it must not be forgotten that the anæsthesia is not always so deep as to prevent sudden reflex movements of the hands, which might jerk the operator’s knife and cause serious mischief.
To obviate the dangers arising from the flow of blood into the pharynx and larynx, it has been recommended by Prof. E. Rose of Berlin to operate with the head hanging over the end of the table, thereby causing the blood to gravitate into the nose. I have only adopted this suggestion in one or two instances, but in those in which it was tried considerable congestion of the vessels of the head was produced, and the administration of the anæsthetic interfered with. A skilled assistant should to my mind render such inversion unnecessary.
Anæsthesia.[87]
The importance of efficient anæsthesia during this operation is so obvious that a few suggestions as to the best means of obtaining and maintaining it will not be out of place. First, as to the choice of an anæsthetic, the conditions of the operation are such that chloroform seems the only agent which is conveniently applicable; our patients moreover are generally children, and with such at any rate it may be safely used. It has been recommended and practised by some to produce initial unconsciousness by the administration of the A. C. E. mixture, ether, or nitrous oxide gas, and then to maintain it with chloroform. This plan is quicker, and supposed to be safer, but on either plea the gain, if any, is so slight as to render the extra complication undesirable.
As to the method of administering chloroform, the old plan of soaking a piece of lint or towel with the drug and applying it closely to the air passages until anæsthesia is produced ought by no means to be followed in these days of advanced knowledge. It is well known that more than 4 per cent. of the vapour of the drug is dangerous, and hence a safer method must be employed. All plans requiring the introduction of nasal or buccal tubes are undesirable. The best method is that recommended and always followed in the practice of my colleague, Sir Joseph Lister. The corner of a well-starched towel fixed into a hollow oval by a safety pin, sufficiently long to extend from the glabella to the point of the chin, is kept continually moist by chloroform from a drop-bottle.
It is held close to the face without actually touching it; and when complete anæsthesia has been induced can be held out of the way of the operator, and yet sufficiently near for the patient to be still affected by the drug. Any opportunity of inserting this adaptable mask into the region of the mouth must be always taken advantage of by the anæsthetist, so that as little delay and inconvenience as possible may be experienced.
During the operation a strict watch must be maintained upon the respiratory functions, so that any laryngeal obstruction may be readily noticed and treated. The colour of the pinna of the ear, the mobility of the tongue, if unrestrained by a gag, and the condition of the conjunctival and pupillary reflexes assist in giving useful indications for an increased or decreased administration when the patient’s face is obscured by hands, instruments, or congealed blood.
When the conjunctival reflex is absent, and the pupil dilated and unaffected by light, the anæsthetic should be temporarily suspended.
When the conjunctival reflex is absent, the pupil contracted, and the colour good, the patient is in the best condition of anæsthesia, and this state should be maintained, if possible, throughout.