Manual of Surgery, Alexis Thomson [new books to read txt] 📗
- Author: Alexis Thomson
- Performer: -
Book online «Manual of Surgery, Alexis Thomson [new books to read txt] 📗». Author Alexis Thomson
Laryngeal Diphtheria.—The disease may arise in the larynx, although, as a rule, it spreads thence from the pharynx. It first manifests itself by a short, dry, croupy cough, and hoarseness of the voice. The first difficulty in breathing usually takes place during the night, and once it begins, it rapidly gets worse. Inspiration becomes noisy, sometimes stridulous or metallic or sibilant, and there is marked indrawing of the epigastrium and lower intercostal spaces. The hoarseness becomes more marked, the cough more severe, and the patient restless. The difficulty of breathing occurs in paroxysms, which gradually increase in frequency and severity, until at length the patient becomes asphyxiated. The duration of the disease varies from a few hours to four or five days.
After the acute sypmtoms have passed off, various localised paralyses may develop, affecting particularly the nerves of the palatal and orbital muscles, less frequently the lower limbs.
Diagnosis.—The finding of the Klebs-Löffler bacillus is the only conclusive evidence of the disease. The bacillus may be obtained by swabbing the throat with a piece of aseptic—not antiseptic—cotton wool or clean linen rag held in a pair of forceps, and rotated so as to entangle portions of the false membrane or exudate. The swab thus obtained is placed in a test-tube, previously sterilised by having had some water boiled in it, and sent to a laboratory for investigation. To identify the bacillus a piece of the membrane from the swab is rubbed on a cover glass, dried, and stained with methylene blue or other basic stain; or cultures may be made on agar or other suitable medium. When a bacteriological examination is impossible, or when the clinical features do not coincide with the results obtained, the patient should always be treated on the assumption that he suffers from diphtheria. So much doubt exists as to the real nature of membranous croup and its relationship to true diphtheria, that when the diagnosis between the two is uncertain the safest plan is to treat the case as one of diphtheria.
In children, diphtheria may occur on the vulva, vagina, prepuce, or glans penis, and give rise to difficulty in diagnosis, which is only cleared up by demonstration of the bacillus.
Treatment.—An attempt may be made to destroy or to counteract the organisms by swabbing the throat with strong antiseptic solutions, such as 1 in 1000 corrosive sublimate or 1 in 30 carbolic acid, or by spraying with peroxide of hydrogen.
The antitoxic serum is our sheet-anchor in the treatment of diphtheria, and recourse should be had to its use as early as possible.
Difficulty of swallowing may be met by the use of a stomach tube passed either through the mouth or nose. When this is impracticable, nutrient enemata are called for.
In laryngeal diphtheria, the interference with respiration may call for intubation of the larynx, or tracheotomy, but the antitoxin treatment has greatly diminished the number of cases in which it becomes necessary to have recourse to these measures.
Intubation consists in introducing through the mouth into the larynx a tube which allows the patient to breathe freely during the period while the membrane is becoming separated and thrown off. This is best done with the apparatus of O'Dwyer; but when this instrument is not available, a simple gum-elastic catheter with a terminal opening (as suggested by Macewen and Annandale) may be employed.
When intubation is impracticable, the operation of tracheotomy is called for if the patient's life is endangered by embarrassment of respiration. Unless the patient is in hospital with skilled assistance available, tracheotomy is the safer of the two procedures.
TetanusTetanus is a disease resulting from infection of a wound by a specific micro-organism, the bacillus tetani, and characterised by increased reflex excitability, hypertonus, and spasm of one or more groups of voluntary muscles.
Etiology and Morbid Anatomy.—The tetanus bacillus, which is a perfect anaërobe, is widely distributed in nature and can be isolated from garden earth, dung-heaps, and stable refuse. It is a slender rod-shaped bacillus, with a single large spore at one end giving it the shape of a drum-stick (Fig. 26). The spores, which are the active agents in producing tetanus, are highly resistant to chemical agents, retain their vitality in a dry condition, and even survive boiling for five minutes.
The organism does not readily establish itself in the human body, and seems to flourish best when it finds a nidus in necrotic tissue and is accompanied by aërobic organisms, which, by using up the oxygen in the tissues, provide for it a suitable environment. The presence of a foreign body in the wound seems to favour its action. The infection is for all practical purposes a local one, the symptoms of the disease being due to the toxins produced in the wound of infection acting upon the central nervous system.
The toxin acts principally on the nerve centres in the spinal medulla, to which it travels from the focus of infection by way of the nerve fibres supplying the voluntary muscles. Its first effect on the motor ganglia of the cord is to render them hypersensitive, so that they are excited by mild stimuli, which under ordinary conditions would produce no reaction. As the toxin accumulates the reflex arc is affected, with the result that when a stimulus reaches the ganglia a motor discharge takes place, which spreads by ascending and descending collaterals to the reflex apparatus of the whole cord. As the toxin spreads it causes both motor hyper-tonus and hyper-excitability, which accounts for the tonic contraction and the clonic spasms characteristic of tetanus.
Fig. 26.—Bacillus of Tetanus from scraping of a wound of finger, × 1000 diam. Basic fuchsin stain.
Clinical Varieties of Tetanus.—Acute or Fulminating Tetanus.—This variety is characterised by the shortness of the incubation period, the rapidity of its progress, the severity of its symptoms, and its all but universally fatal issue in spite of treatment, death taking place in from one to four days. The characteristic symptoms may appear within three or four days of the infliction of the wound, but the incubation period may extend to three weeks, and the wound may be quite healed before the disease declares itself—delayed tetanus. Usually, however, the wound is inflamed and suppurating, with ragged and sloughy edges. A slight feverish attack may mark the onset of the tetanic condition, or the patient may feel perfectly well until the spasms begin. If careful observations be made, it may be found that the muscles in the immediate neighbourhood of the wound are the first to become contracted; but in the majority of instances the patient's first complaint is of pain and stiffness in the muscles of mastication, notably the masseter, so that he has difficulty in opening the mouth—hence the popular name “lock-jaw.” The muscles of expression soon share in the rigidity, and the face assumes a taut, mask-like aspect. The angles of the mouth may be retracted, producing a grinning expression known as the risus sardonicus.
The next muscles to become stiff and painful are those of the neck, especially the sterno-mastoid and trapezius. The patient is inclined to attribute the pain and stiffness to exposure to cold or rheumatism. At an early stage the diaphragm and the muscles of the anterior abdominal wall become contracted; later the muscles of the back and thorax are involved; and lastly those of the limbs. Although this is the typical order of involvement of the different groups of muscles, it is not always adhered to.
To this permanent tonic contraction of the muscles there are soon added clonic spasms. These spasms are at first slight and transient, with prolonged intervals between the attacks, but rapidly tend to become more frequent, more severe, and of longer duration, until eventually the patient simply passes out of one seizure into another.
The distribution of the spasms varies in different cases: in some it is confined to particular groups of muscles, such as those of the neck, back, abdominal walls, or limbs; in others all these groups are simultaneously involved.
When the muscles of the back become spasmodically contracted, the body is raised from the bed, sometimes to such an extent that the patient rests only on his heels and occiput—the position of opisthotonos. Lateral arching of the body from excessive action of the muscles on one side—pleurosthotonos—is not uncommon, the arching usually taking place towards the side on which the wound of infection exists. Less frequently the body is bent forward so that the knees and chin almost meet (emprosthotonos). Sometimes all the muscles simultaneously become rigid, so that the body assumes a statuesque attitude (orthotonos). When the thoracic muscles, including the diaphragm, are thrown into spasm, the patient experiences a distressing sensation as if he were gripped in a vice, and has extreme difficulty in getting breath. Between the attacks the limbs are kept rigidly extended. The clonic spasms may be so severe as to rupture muscles or even to fracture one of the long bones.
As time goes on, the clonic exacerbations become more and more frequent, and the slightest external stimulus, such as the feeling of the pulse, a whisper in the room, a noise in the street, a draught of cold air, the effort to swallow, a question addressed to the patient or his attempt to answer, is sufficient to determine an attack. The movements are so forcible and so continuous that the nurse has great difficulty in keeping the bedclothes on the patient, or even in keeping him in bed.
The general condition of the patient is pitiful in the extreme. He is fully conscious of the gravity of the disease, and his mind remains clear to the end. The suffering induced by the cramp-like spasms of the muscles keeps him in a constant state of fearful apprehension of the next seizure, and he is unable to sleep until he becomes utterly exhausted.
The temperature is moderately raised (100° to 102° F.), or may remain normal throughout. Shortly before death very high temperatures (110° F.) have been recorded, and it has been observed that the thermometer sometimes continues to rise after death, and may reach as high as 112° F. or more.
The pulse corresponds with the febrile condition. It is accelerated during the spasms, and may become exceedingly rapid and feeble before death, probably from paralysis of the vagus. Sudden death from cardiac paralysis or from cardiac spasm is not uncommon.
The respiration is affected in so far as the spasms of the respiratory muscles produce dyspnœa, and a feeling of impending suffocation which adds to the horrors of the disease.
One of the most constant symptoms is a copious perspiration, the patient being literally bathed in sweat. The urine is diminished in quantity, but as a rule is normal in composition; as in other acute infective conditions, albumen and blood may be present. Retention of urine may result from spasm of the urethral muscles, and necessitate the use of the catheter.
The fits may cease some time before death, or, on the other hand, death may occur during a paroxysm from fixation of the diaphragm and arrest of respiration.
Differential Diagnosis.—There is little difficulty, as a rule, in diagnosing a case of fulminating tetanus, but there are several conditions with which it may occasionally be confused. In strychnin poisoning, for example, the spasms come on immediately after the patient has taken a toxic dose of the drug; they are clonic in character, but the muscles are relaxed between the fits. If the dose is not lethal, the spasms soon cease.
Comments (0)