For squint operations it is desirable to have a light fixed to the ceiling, directly over the head of the operating table, for testing the position of the eyes either by the reflection of the light from the surface of the cornea or by the Maddox rod test.
The operating table should be provided with a means of adjusting its height and the position of the head-piece, so that the patient’s head can be brought to about the level of the operator’s elbows when the latter is standing upright with his arms at his side.
After operation the patient should be warned to lie still and not to strain in any way; he should be carried to bed and should lie on his back if possible. If a patient cannot sleep on his back it is better that he should lie on the sound side than be without rest. A length of bandage should be fastened round the wrist of the hand on the same side as the eye which has been operated upon, and should be attached to the bed so as to prevent the hand being put up to the eye during sleep. After major operations, such as those for cataract and glaucoma, the patient is confined to bed for ten days, during the first four of which the head should not be raised from the pillow, the bowels being evacuated while the patient is in the supine position; but old patients with a tendency to bronchitis or hypostatic pneumonia must be propped up in bed and allowed to get up earlier: in these patients it is better to perform the operation in the summer if possible. In old people and patients with a tendency to melancholia the mental condition must be carefully watched, as frequently they cannot stand the confinement to bed and darkness.
LOCAL PREPARATION OF THE PATIENT
When operating upon the eye, a surgeon has to face the great difficulty that he is operating in an area which is not always aseptic, since it is practically impossible to render the conjunctival sac sterile. At the same time, the conjunctiva has been shown to be sterile in health in 25% of cases, pyogenic organisms (principally the staphylococcus albus) being found only in 15%; but, although these are usually not of a very virulent character, they are by far the most frequent cause of sepsis; ten cases of suppuration after operation which the author has examined were all due to this organism. After the methods of purification given below, this percentage is considerably reduced, so that, if due precautions are taken, the risk of sepsis is comparatively small. On the other hand, if conjunctivitis or lachrymal obstruction be present, the risks are enormously increased, especially in the latter condition owing to the frequent presence of the pneumococcus in the discharge, unless special precautions are taken. It is, therefore, of the utmost importance that every case should be examined for lachrymal obstruction before operation. Care should be taken also to see that there is no purulent discharge from the nose or any septic sores about the face.
Sepsis after intra-ocular operations manifests itself in one of two forms: either by suppuration, which usually ends in a rapid and complete destruction of the eye (panophthalmitis), or more rarely in less virulent cases by recurrent attacks of hypopyon associated with acute irido-cyclitis; or by a plastic irido-cyclitis, which may lead to slow disorganization of the eye, with always the possibility of destruction of the other eye by sympathetic cyclitis (sympathetic ophthalmia). Although these conditions are comparatively rare, owing to the improvement in modern aseptic and antiseptic methods, every surgeon of experience will meet with these disastrous complications; indeed it has been suggested that immunization with staphylococcus vaccine should be carried out before major intra-ocular operations, since infection is generally due to this organism.
The methods of purifying the eye before operation. On the second night previous to the operation the eye should be bandaged and examined the following morning for conjunctival discharge. If any be present, an examination for organisms should be made, and the operation postponed until the conjunctival condition has improved. In the event of the case being extremely urgent, the conjunctiva should be swabbed over with nitrate of silver (10 gr. to the oz.) immediately before the operation; some surgeons prefer 1–2,000 perchloride of mercury. If lachrymal obstruction be present, the sac should be thoroughly washed out with boric lotion and protargol (10%) injected. The canaliculi may be temporarily occluded subsequently (see [p. 294]). If the lashes be very long they should be cut short. Epilation is performed by some Continental surgeons, but is not practised in this country. Various forms of specula are made to keep the lashes out of the field of operation; of these, a modification of Lang’s is perhaps the best (Fig. 76).
Fig. 76. Lang’s Eye Speculum. Designed to hold the lashes away from the field of operation.
On the morning of the operation the lids should be thoroughly cleansed with soap and water, followed by 1–2,000 solution of perchloride of mercury, special attention being paid to the lid margins and lashes. The conjunctival sac should be washed out with boric lotion and a pad of cyanide gauze applied over the closed lid.