Chapter 84
[43] For a description of this method see _Metropol. Asylums Board's Ann. Rep., Med. Supplem._, 1898, p. 187.
_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 a.s.sistants 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 haemorrhage, emphysema, or abscess. In rare instances a false pa.s.sage 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 dyspna 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]
[44] _Operations of Surgery_, 5th ed., vol. i, p. 640.
'_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 dyspna is relieved and the expectoration easy; with intubation, on the other hand, there is no stage of apna after introduction, which seems to indicate that the air does not pa.s.s 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 cla.s.ses:
(_a_) Pointed; such as bones, needles, teeth, nails, &c.
(_b_) Rounded; i. Hard, such as coins, stones, or b.u.t.tons.
ii. Soft (in some cases capable of swelling), such as meat, beans, peas.
(_c_) Fluid; such as blood, pus, or vomited food.
To these may be added pieces of necrosed cartilage from the larynx, trachea, or bronchi; and calcareous concretions from bronchial glands, which occasionally perforate the walls of the air-pa.s.sages.
Any of the above may become impacted in the trachea or fall into one of the bronchi: the right bronchus is affected nearly twice as often as the left owing to its larger size, its direction (which is more nearly that of the trachea), and the inclination of the septum to the left of the middle line.
(ii) _Tumours of the trachea_ (see p. 546).
(iii) _Stricture of the trachea_ resulting from previous inflammation or trauma. Tracheoscopy is useful both for accurate diagnosis and for treatment of such conditions. The following case may be quoted as an ill.u.s.tration: A boy of 17 was admitted to my hospital on account of dyspna, caused by obstruction in the lower air-pa.s.sages. The chest was examined and a skiagram taken, the latter showing a definite shadow in the position of the bifurcation of the trachea. This was possibly an enlarged gland which pressed upon the trachea. I decided to give the boy an anaesthetic and perform tracheoscopy. On pa.s.sing the
(iv) _For diagnostic purposes_ alone, to determine the cause of pressure upon the air-pa.s.sages; as in tumours of the mediastinum, aneurism, and the like.
The instruments required correspond in the main to those used for direct laryngoscopy (see p. 480). The special instruments include (_a_) bronchoscopes, which are long circular tubes of dimensions suitable to the patient:
LENGTH AND SIZE OF TUBE REQUIRED IN UPPER BRONCHOSCOPY (KILLIAN)
_Adults._ _Children._
Length 30-40 cm. 20-30 cm.
Diameter 9-14 mm. 5-7 mm.
These should be marked externally in centimetres, measured from the distal end of the tube, and should be provided with a lateral window to allow of free breathing through the opposite bronchus when the tube is introduced into the one which is obstructed; of the various forms in use, the sliding tube of Bruenings appears to me superior; (_b_) instruments for extraction, including forceps and hooks according to the nature of the body to be removed; (_c_) aspirator for removal of mucus, and sponge-holders, the length of the bronchoscope.
=Operations= (see also p. 481). As regards the anaesthetic, chloroform is preferable in children, but in adults cocaine may suffice. The operations are best performed in a room which can be made dark.
=Tracheoscopy.= The preliminary stages are similar to those of direct laryngoscopy. If the larynx be found normal, a smaller tube can be pa.s.sed through the tube-spatula between the vocal cords, and the spatula can then be divided and removed in separate halves. In Bruening's instrument the inner tubes are so constructed that they can be pushed through the outer tube and made to project like a telescope to any desired distance. In this way the subglottic region and trachea can be explored.
[Ill.u.s.tration: FIG. 277. INSTRUMENTS FOR BRONCHOSCOPY. Bronchoscopes: A, Killian's; B, Jackson's; C, Bruening's. D, Instruments for extraction.
E, Handle (Watson Williams's).]
=Upper bronchoscopy.= The tubes are pa.s.sed through the mouth, and the inner one is projected until the bifurcation of the trachea is visible.
In order to avoid injury to the tissues, the operation should be performed entirely by sight and with great care. Three cases have been recorded where tracheotomy was needed for the relief of dyspna caused by dema of the larynx which had followed traumatism.
The tube having been pa.s.sed, cocaine (10%) is applied to the bifurcation of the trachea, and mucus is removed by sponging or by an aspirator. If the secretion be excessive, the foot of the table should be raised so that the mucus drains away from the part to be explored.
It is the duty of the anaesthetist or some competent a.s.sistant to note that normal respiration is maintained, and the necessity for tracheotomy or artificial respiration must always be borne in mind.
[Ill.u.s.tration: FIG. 278. INSTRUMENTS FOR BRONCHOSCOPY. A, Aspirator for mucus; B, Sponge-holder; C, Hooks.]
If the operator be experienced, bronchoscopy can be performed without endangering the patient's life even in the case of a young child. A baby of eight months has been successfully treated by this method.
=Lower bronchoscopy.= Preliminary tracheotomy (median or low) having been performed, a wide tube is introduced into the bronchus through the wound in the trachea. This method has the following advantages: It is easier to perform, and the surgeon requires less experience of technique; the tube, being wider, is more readily illuminated; there is little danger of asphyxia; in pa.s.sing the tube no organisms are introduced from the mouth, and there is less danger of pneumonia. If these advantages are weighed, it becomes apparent that the lower operation is preferable for surgeons without experience. In all cases with urgent dyspna preliminary tracheotomy is practically essential.
By a combination of the above methods the diagnosis of foreign bodies can be positively determined in the majority of cases. As Killian said in 1902: 'We have now reached a position in which, in many cases at least, one can not only obtain a positive result but with confidence can a.s.sert that the foreign body is not present.' In support of this statement numerous cases have been reported, especially in Germany and America. Von Eicken, in 1904, collected 42 cases of bronchoscopy, in 35 of which a definite diagnosis of a foreign body was made; in 4 it was shown that none was present; and in 3 only were negative results obtained. Since that time the results have been equally good, for in 1907 Killian increased this number to 164 reported cases in which a foreign body had been actually discovered.
As soon as the foreign body is clearly seen, a pair of forceps is selected and introduced through the tube. The object is grasped and drawn through the tube, if this be possible, or the tube and forceps may be withdrawn together from the trachea. If the foreign substance be broken the operation can be repeated until all of it has been removed.
If the patient becomes collapsed it may be necessary to postpone the continuation of the treatment until the following day. A second attempt is often successful when the first has proved a failure.
Bronchoscopy is comparatively easy to perform (_a_) when the foreign body lies in the trachea or main bronchus; (_b_) when the foreign body has been accurately located; or (_c_) when the operation can be performed early, before inflammation has supervened. In the rare instances where the body lies in one of the secondary or tertiary bronchi, or has penetrated the substance of the lung, the difficulties are much increased, and in such conditions the question of the advisability of lower bronchoscopy should be considered.
=Complications= seldom occur after removal of foreign bodies by these methods if the surgeon is careful to avoid injury when pa.s.sing the tubes. There may be temporary hoa.r.s.eness owing to congestion of the mucous membrane. Ingals has reported two cases in which death occurred soon after the operation, with symptoms like those of delayed poisoning from an anaesthetic, and has raised the question whether it is advisable to use cocaine or atropin[e] in these operations. Delavan, on the other hand, suggests that injury to the pneumogastrics may account for such collapse. As stated above, the combination of chloroform and cocaine does not appear to be dangerous if used with discretion.
[Ill.u.s.tration: FIG. 279. UPPER BRONCHOSCOPY WITH THE PATIENT IN THE DORSAL POSITION.]
[Ill.u.s.tration: FIG. 280. LOWER BRONCHOSCOPY WITH THE PATIENT IN THE DORSAL POSITION.]
=Results.= Removal of foreign bodies by bronchoscopy gives far better results than the older methods of treatment such as tracheotomy, bronchotomy, and thyrotomy. With the last-named operations more than one-third of the cases have been fatal: while on the other hand, taking the 164 cases[45] collected by Killian, it is found that in 159 (leaving out 5 with unknown result) only 21 (or 13%) died, viz. 2 from cocaine; 2 because it was impossible to remove the object on account of bronchial stenosis; 1 from suffocation in spite of upper and lower bronchoscopy; and the remaining 16 of pulmonary complications--5 with the foreign body in the lung, and the others in spite of its removal. Upper bronchoscopy was fully successful in 54 cases, and lower bronchoscopy in 63. The result of the remaining 21 operations is not stated.
[45] _Trans. Amer. Laryng. and Otol. Soc._, 1907, p. 80, 'The Treatment of Foreign Bodies in the Respiratory Tract and Esophagus.'
Speaking of his own cases, Killian writes: 'My own statistics give perhaps a better judgment for the future of cases of foreign bodies in the deeper air-pa.s.sages than the general, since I have gradually acquired a larger experience and more practice. Nevertheless, I have the impression that in many cases my technic has not reached the highest mark, and I hope to obtain better results in the future. As shown by the list of cases, only one death resulted in the eighteen cases, and this was six months after the removal of the foreign body, caused by severe lung complication due to its long sojourn in the air-pa.s.sages. In only two cases was I unable to find the foreign body and in only one was I unable to remove it on account of its being coughed up.
'Upper bronchoscopy was performed in twelve cases, upper and lower in five, and lower tracheo-bronchoscopy in one. However, I hope in the future, with improved technic, to be successful with the upper method at the first sitting and to use the lower only in the severest cases.'
To Killian of Freiburg is due the chief credit for having introduced a safe method of treatment, the value of which is at last beginning to be generally recognized in England. As Paterson[46] says, 'it is earnestly to be hoped that the time has now come when workers in this country will recognize its enormous advantages.'
[46] _Brit. Med. Journ._, 1906, vol. ii, p. 357, 'The Direct Examination of sophagus and Upper Air-pa.s.sages.'
SECTION V