It is very important to remember that tracheotomy is required in nearly a third of the cases at one stage or another; at the M. A. B. fever hospitals of London during 1902–6 there were 429 cases of intubation for diphtheria, and of these 117 required tracheotomy later, i.e. 27.2%. As Goodall says: ‘Every case that was intubated four or more times came to tracheotomy. I therefore lay down the rule that if three insertions, each of several hours’ duration, fail to cure the laryngeal obstruction, tracheotomy should be performed. Frequent expulsion of the tube by coughing a few minutes after its insertion is also an indication for tracheotomy.’

After-treatment. A case of intubation requires more personal attention than one of tracheotomy. It is essential that the doctor should remain within easy call, as the tube may be blocked or coughed out at any moment. This danger is not so great as it appears; when the tube is coughed out there is no immediate asphyxia, and a fatal result is uncommon; an interval of at least twenty minutes usually occurs before the dyspnœa becomes urgent, in which time the doctor can be called; it may even happen that the tube is not required again, and that the obstruction has disappeared. When the tube becomes blocked, the state is more serious; in most cases it will be coughed out of the larynx, but if the child is very weak or the tube very firmly fixed, the obstruction must be at once relieved. It is for this reason that some surgeons prefer to leave a thread attached so that the nurse can extract the tube, but the latter has a disadvantage, namely, that the child may pull the tube out. This can be prevented by tying up the hands of the child while the tube is being worn, but even then the child may bite the string; the general practice therefore is to remove the thread, and the tube is then expressed by lateral pressure on the sides of the trachea, or by passing the finger below and behind the larynx and so pushing out the tube. The method is termed ‘enucleation’,[43] and where it fails the extubator must be used. A nurse must be chosen who has had previous experience of intubation; she must understand the symptoms which necessitate interference with the tube, and the feeding of the child. Swallowing is often difficult, and liquids tend to pass through the canula into the trachea; the patient chokes and may cough up the tube. The danger of pneumonia is also increased. To overcome the dysphagia the patient should be made to suck uphill through a tube, or semi-solids may be tried: in other cases nasal or rectal feeding can be ordered: temporary removal of the tube has also been recommended for purposes of feeding, but vomiting often occurs with reintroduction immediately after a meal. In very troublesome cases there is distinct danger in repeated intubation; tracheotomy should be performed if the child is becoming exhausted from want of nourishment.

Changing the tube. O’Dwyer recommends that the tube should be retained for forty-eight hours without change, after which it should be removed once a day: it must, however, be remembered that while the tube is retained coughing is greatly impeded, so that septic material collects in the trachea and is liable to cause pneumonia.

Extubation by the thread and by enucleation has already been mentioned, but these methods are not applicable in every case. Extubation is difficult to perform, especially if respiration is obstructed and the patient struggling; whenever necessary, chloroform should be given. The preparation required is similar to that for intubation; a table and tracheotomy instruments are made ready; the upright position is preferred, and two assistants are required to hold the child and the gag; expanding forceps are introduced as if intubation were being done, and the tube is grasped securely and rapidly extracted, the whole operation being carried out as quickly as possible and without any suggestion of force. In experienced hands no danger is to be feared, but if two or three attempts are unsuccessful, tracheotomy should be performed. The time for removal of the tube varies from a few hours to four or five days in favourable cases. The main object is to dispense with the tube as soon as possible, and to err on the side of too early removal even in spite of the fact that reintroduction may be necessary.

Complications may occur, but there is no evidence that they are more numerous than with tracheotomy. Injury to the larynx is liable to result, especially from inexperience of the method, and this may be followed by hæmorrhage, emphysema, or abscess. In rare instances a false passage has been made, generally through the ventricle of the larynx: pressure ulcers may form, there may be necrosis of the cartilage, peritracheal abscess, or cicatricial contraction; or, as with tracheotomy, subglottic swelling may persist and granulations may be formed. When urgent dyspnœa follows the removal of the tube, one of these conditions must be suspected. O’Dwyer maintains that ‘the cause of persistent stenosis following intubation in laryngeal diphtheria can be summed up in a single word—traumatism,’ but ‘paralysis of the vocal cords may possibly furnish an occasional exception to this rule’ (Jacobson).[44]

‘Retained tube,’ which is the term applied to cases of more than five days’ duration, is certainly more common after injury, but does not occur more frequently than with tracheotomy; many cases have been reported where intubation tubes were used for long periods with ultimate recovery, but the method is uncertain unless the exact condition of the larynx can be determined (see [p. 480]).

Pneumonia. It has been shown that large numbers of bacilli are present in the lungs, where they may cause inflammation quite apart from any operation; in laryngeal cases the danger is increased owing to the obstruction which causes deficient aeration of, and improper expectoration from, the lung. Where tracheotomy is performed the dyspnœa is relieved and the expectoration easy; with intubation, on the other hand, there is no stage of apnœa after introduction, which seems to indicate that the air does not pass so easily through the smaller tube; coughing is more difficult and the amount of expectoration less; mucus, pus, or membrane in small pieces, can all be expelled through the tube, but not so freely as through the larger canula, and are more likely to be swallowed. For these reasons it would appear that pneumonia is less to be feared after tracheotomy; there is, however, considerable difference of opinion on this point, and statistics have not proved of great value.

CHAPTER V
TRACHEOSCOPY AND BRONCHOSCOPY

Indications. (i) Foreign bodies. Accidental inhalation of foreign bodies is more common in children than in adults in the proportion of about two to one. The character of the foreign body should be considered before treatment is advised, and for this purpose the inhaled bodies may be divided into three classes: