In considering the prognosis, not only must the symptoms peculiar to the case be taken into account (as for instance the pulse, temperature, respiration and general condition), but also any complications that arise. It must be borne in mind that tracheotomy does not cure, although it can relieve, the patient; that nearly one-third of the cases die; that the disease, and not the operation, is responsible for most of the deaths. Moreover, the amount of toxæmia depends upon the virulence of the infection, which is variable in different epidemics; upon the area of mucous membrane infected; and upon the constitution of the patient. In so-called hæmorrhagic diphtheria the result is always fatal.

The effect on after-life. It was stated by Landouzy at the Berlin Tuberculosis Congress in 1899 that, judging by the rarity of the scar, few tracheotomized children reach adult life, but inquiries in Germany showed that this was incorrect. H. W. L. Barlow, in reviewing the literature of the subject, concludes that ‘in the large majority of cases the cure is permanent and complete’. In cases where a tracheotomy tube has been retained for a long period, however, complications are liable to arise; these include stenosis of the larynx or trachea, bronchitis, pneumonia, and possibly tuberculosis (see [p. 485]).

TRACHEOTOMY IN CONDITIONS OTHER THAN DIPHTHERIA

The indications for tracheotomy in conditions other than diphtheria have already been described. Although local anæsthetics are of little practical value in children, their use is much preferred where adults are concerned. The three drugs most commonly used at the present time are eucaine, cocaine, and novocaine, and of these novocaine is unquestionably to be preferred for subcutaneous injection as being less toxic, less irritant to the tissues, and at least as efficient in producing anæsthesia. Whichever drug is chosen, a small quantity of chloride of sodium should be added in order to make the solution isotonic with the blood serum, and thus to render it practically non-irritant. Many surgeons add adrenalin to contract the vessels in the injected area and so to prevent the drug from being absorbed into the general circulation: owing to the large size of the vessels and their proximity to the heart this is important, but it must also be remembered that with strong solutions there is great contraction of vessels, and that when the effects have disappeared there is a slight danger of recurrent hæmorrhage. Semon has drawn attention to this danger in connexion with operations upon the larynx, and after minor operations in other regions of the body it is not uncommon to find a small hæmatoma which necessitates reopening the wound.

In order to ensure the full effects of local anæsthesia with the least possible disadvantage, the drug should be used in weak solution, and the injection should be made at least a quarter of an hour before the operation is commenced. It is only necessary to prick the skin at one point, namely, at the upper end of the proposed incision; a small quantity of the fluid should be expelled, after which the needle may be withdrawn. After a short interval it is possible to reinsert the needle (or a larger one if preferred) and to push it deeper, until the whole length of the incision has been injected, without distress to the patient.

The following solution will be found effective:

‘Novocaine, 4% solution[ɱ] x = 1.3%
‘Sodium chloride, 4% solutionɱ vj = 0.8%
‘Adrenalin, 1–1,000ɱ i = 0.003%
‘Distilled water toɱ xxx

‘These local anæsthetics are all, more or less, rapidly decomposed and rendered inactive in the presence of even traces of an alkali or alkaline carbonate. If boiling is resorted to in order to sterilize the syringe, great care must be taken that no soda is present.’—Lang.

Moreover, the finished solution cannot be boiled without decomposing the adrenalin, and it is customary therefore to add thymol or Ol. Gaultherii (0.1%), which keeps the solution antiseptic without being irritant.

The operation, which is often required in adults, must be carried out upon the lines already described. The enlargement of the thyreoid and cricoid cartilages, the small amount of fat, the small size of the thyreoid isthmus and of the pretracheal vessels after puberty, make the trachea easy to find. Difficulties, however, arise and are determined by the urgency of the case and the nature of the disease. Thus, with inflammation, the neck may be so swollen that the trachea is many inches from the surface; with tumours the trachea may be displaced, or the obstruction may be in the thorax. Under such conditions it is important to note the probable position of the trachea before the operation is commenced, and to be prepared for serious hæmorrhage.