Acute upper airway obstruction - Science Direct

0 downloads 0 Views 4MB Size Report
Acute upper airway obstruction continues to challenge medical practitioners who care for children. Whilst usually straightforward, management can be compli-.
I Mini

Respiratory diseases

symposium

Acute upper airway obstruction

H. A. Kilham, J. A. McEniery Acute upper airway obstruction continues to challenge medical practitioners who care for children. Whilst usually straightforward, management can be complicated by incorrect diagnosis, unexpected deterioration, difficulty in assessing the need for intubation, difficulty in providing optimal intubation skills and confusion over the value of various therapies. The highest priority is preventing death or hypoxic injury in those few children who progress to profound obstruction. In this overview, the term laryngotracheitis is used as a synonym for croup and laryngotracheobronchitis, epiglottitis is used as a synonym for supraglottitis, and bacterial tracheitis is used as a synonym for pseudomembranous croup. The term ‘intubation’ is used as an abbreviation for mechanical relief of airway obstruction.

-Obstruction . Dynamic collapse of extrathoracic trachea . Strongly negative pressure relative to atmospheric pressure

Pathophysiology

Fig.

Why inspiratory disJiculty predominates

difficulty

expressed

diagrammatically.

The respiratory rate in children with upper airway obstruction is usually only mildly or moderately increased. Rapid respiratory rates allow insufficient time for the prolonged inspiratory effort.

Upper airway obstruction generally causes cough, stridor and respiratory difficulty. The inspiratory/ expiratory ratio is prolonged. Unless the obstruction is intrathoracic, stridor and respiratory difficulty are more prominent during inspiration. This results from dynamic collapse of the extrathoracic trachea, only during inspiration, below the level of obstruction, due to the strongly negative intratracheal pressure relative to external (atmospheric) pressure. This is shown in Figure I. This effect is exaggerated by sudden, stronger inspiratory efforts such as occur, for instance, with crying or sighing. The addition of persistent crying to airway obstruction may precipitate the need for intubation which might otherwise have been unnecessary.

Why dyspnoea can vary abruptly

Respiratory difficulty does not become apparent until quite marked airway narrowing is present. Once this point is reached very little additional narrowing will be accompanied by a large increase in airways resistance and thus respiratory difficulty. The subglottic region is ovoid, not circular and in a lZmonth-old child it may measure 6 by 4 mm. With severe laryngotracheitis the opening may be reduced to a ‘slit’ 3 or 4 mm by 0.5 or 1 mm. Then a small increase in mucous secretions or mucosal oedema may be sufficient to cause abrupt deterioration, whilst a small decrease in mucosal oedema, for instance as a result of nebulised

Dr. H. A. Kilbam and Dr J. A. McEniery, Department of Medicine, The Children’s Hospital, Camperdown, NSW 2050, Australia. Correspondence and requests for offprints to HAK. C’urrent Paedumcs (1991) 1. 17-25 ‘(” 1991 Longman Group UK Ltd

1-lnspiratory

17

18

CURRENT

PAEDIATRICS

adrenaline, may lead to considerable, if transient improvement. Events in progressive upper airway obstruction

Children with progressive upper airway obstruction maintain tidal volume, with increasing effort, to the point of exhaustion. Arterial pH and pC0, remain normal or near-normal until a short time before collapse occurs. Hypoxia is much more variable. It is usually due to V/Q mismatch resulting from lower airways secretions, bronchospasm and patchy consolidation. It is due to hypoventilation only in terminal situations. Pulse oximetry has demonstrated some correlation between increasing tachypnoea and worsening desaturation, but overall it correlates poorly with the degree of obstruction. Blood gas analysis and pulse oximetry are of little predictive value in acute upper airway obstruction, becoming markedly abnormal only when decompensation has occurred. Physical signs (increasing tachypnoea, increasing tiredness and apathy) are of much greater value in predicting the need for intubation. Collapse occurs when respiratory muscle effort can no longer be maintained. Characteristically it occurs abruptly, with progressive hypoxia and cardiac arrest if intervention is not immediate and effective. Good management involves awareness of this sequence, with anticipation of the need for intervention.

Clinicalentities Diagnosis is made largely on clinical features. X-rays and other diagnostic methods are of very limited value. Acute laryngotracheitis

The commonest cause of acute upper airway obstruction, this affects boys more often than girls. The usual age range is six months to three years though Table

1

Causes

of acute

upper

Supraglottic epiglottitis acute tonsillar enlargement retropharyngeal abscess foreign body acute angioedema

airway

obstruction

(bacterial,

EBV)

Laryngeal/subglottic acute laryngotracheitis spasmodic croup bacterial tracheitis foreign body diphtheria thermal/chemical injury intubation trauma laryngospasm, (neural, hypocalcaemia, associated with reflux) Tracheal trauma tumour foreign

(haematoma) (anterior mediastinal body (oesophageal,

lymphoma) tracheal)

children of any age can be affected. Parainfluenza, respiratory syncytial and influenza viruses are the usual causes. Mucosal inflammation and secretions affect most of the respiratory tract but obstruction occurs at the subglottic region of the trachea which is the narrowest part of the airway in young children. After mild coryzal symptoms for a few days, a harsh barking cough, hoarse voice and inspiratory stridor develop. These symptoms are usually worse at night, persist intermittently for several days then resolve except that the cough continues a few more days. Occasionally increasingly severe respiratory difficulty develops with tachycardia, mild or moderate tachypnoea, chest wall retractions and agitation. Severe upper airway obstruction may warrant relief by intubation. Spasmodic croup

Believed to be allergic rather than infective, this condition tends to affect pre-school and school-age children. Typically a loud barking cough and inspiratory stridor develop suddenly at night, with minimal or no preceding respiratory tract symptoms or fever. The symptoms resolve rapidly and recurrent episodes are common. There is often a past history or family history of asthma. Occasionally an episode of spasmodic croup evolves into asthma. Occasionally spasmodic croup appears to respond to anti-asthma drugs. Rarely, intubation is required. The distinction between acute laryngotracheitis and spasmodic croup is often blurred. As management of both conditions is essentially the same the distinction is not of great importance. Acute epiglottitis

The distinction between croup and epiglottitis is of the greatest importance because of the rapidly progressive and dangerous nature of epiglottitis. Croup ‘bespeaks its name’ whilst epiglottitis, in its early stages is subtle with no distinguishing features. It is much less common than croup, usually affects a slightly older age-group and may well present in daytime. It occasionally occurs in young infants and even adults. It is almost always due to Haemophilus influenzae type b but very similar illnesses are occasionally caused by streptococci and some viruses. For unknown reasons, its incidence varies both between countries and in proportion to haemophilus-related meningitis. Typically there is acute onset of fever and sore throat. Drooling and a muffled voice reflect the reluctance to swallow or talk due to pain. The child appears toxic and lethargic. Over 6-12 hours the supraglottic structures swell and encroach upon the airway at the level of the vocal cords. Inspiratory stridor if audible is usually quiet and has a wheezy quality. Cough is rare as the larynx and trachea are not involved. The child adopts a posture which provides the best airway, often sitting and leaning forward with the head in the ‘sniffing’ position. Some children lie supine with the head retracted. The child is apprehensive and resists

ACUTE UPPER AIRWAY

any attempts by others to alter his or her chosen posture. He may breathe cautiously and slowly such that there may be little apparent respiratory distress. Throat examination should be avoided if epiglottitis is suspected. However the diagnosis has been made in the early stages by observing a swollen hyperaemic (‘cherry red’) epiglottis. The disease is rapidly progressive and most children will proceed to profound airway obstruction. Urgent intervention is almost always necessary. Bacterial tracheitis

This rare condition, usually associated with infection by Staphylococcus aureus or Haemophilus influenzae type b, can arise de novo or complicate acute laryngotracheitis. Children with Down syndrome seem particularly at risk. The clinical picture is similar to croup except that the child has a high fever, appears toxic and usually has rapidly progressive airway obstruction. Copious thick secretions can be aspirated from the trachea. Gram stain of secretions will often demonstrate micro-organisms. Foreign body

Aspiration of a foreign body must always be considered in the differential diagnosis of acute upper airway obstruction. Toddlers aged 9-24 months are at particular risk. The foreign body may be supraglottic, laryngeal, tracheal (usually subglottic) or oesophageal, compressing the trachea from behind. Frequently the aspiration or a choking episode is witnessed. If not, rapid onset of symptoms without a prodrome of fever or upper respiratory symptoms may suggest the diagnosis. The symptoms are generally the same as those of acute laryngotracheitis. The symptoms may change rapidly if the foreign body is mobile. Tonsillar obstruction

Acute tonsillitis in a child with tonsillar hypertrophy may cause sufficient supraglottic obstruction to cause acute severe upper airway obstruction. In older children with Epstein Barr virus infection tonsillar and pharyngeal swelling may cause severe obstruction though intubation is virtually never required. Quinsy (peritonsillar abscess) rarely occurs in children; it is much more common in adolescents and young adults. It tends to follow severe tonsillitis. Symptoms and signs include very sore throat, fever, severe dysphagia, trismus and grossly asymmetrical tonsillar swelling. Retropharyngeal abscess

This unusual condition is due to progression of bacterial pharyngitis or pharyngeal trauma. It occurs mainly in very young infants. Soft stridor is accompanied by fever, drooling, cervical lymphadenopathy, diffuse swelling of the neck and a posture of neck

OBSTRUCTION

19

extension. Oral anaerobes and gram negative organisms are the usual pathogens. Diphtheria

This rare but dangerous condition should be considered in any unimmunised child with acute upper airway obstruction. Initial symptoms may be those of laryngotracheitis. In addition there is usually a very sore throat, halitosis, the presence of a grey adherent membrane over the pharynx and/or tonsils and disproportionate tachycardia if toxin-induced myocarditis has developed. Mortality remains between 5-10% largely because of myocarditis. Trauma

Various types of trauma may cause acute upper airway obstruction. A haematoma from blunt trauma may cause extrinsic tracheal obstruction. Laryngeal and subglottic damage from intubation is well-recognised and is occasionally severe. Inhalation of flames, smoke and hot gases may produce thermal and chemical damage to laryngopharynx, larynx and trachea of sufficient severity to require intubation and subsequently tracheostomy. Zntra-thoracic tracheal obstruction

Upper mediastinal lymphoma may enlarge so rapidly that acute upper airway obstruction may be the presenting symptom. A previously unrecognised congenital malformation e.g. vascular ring will occasionally cause acute upper airway obstruction. Foreign bodies may be intrinsic or extrinsic. Other rare conditions

Acute angioneurotic oedema is occasionally seen in older children. Presumably allergic, the precipitant is often not found. Rapidly progressive upper airway obstruction is accompanied by face and neck swelling. Hereditary angio-oedema and exercise-induced oedema also occur. Acute bilateral vocal cord paresis has been described following treatment with vincristine. Hypocalcaemia can cause episodes of acute laryngospasm which have been mistaken for croup. Episodes of stridor and respiratory difficulty can be associated with gastro-oesophageal reflux.

Assessingseverity of obstruction Deciding the optimal timing of intervention in those few children who require intubation is one of the most difficult assessments in paediatric practice, even for the experienced. Unnecessary intubation is as much to be avoided as desperate late intubation; both will add to morbidity and mortality. Repeated careful clinical observation is of greatest value. An overall impression from the end of the bed

20

CURRENT

PAEDIATRICS

is more important than individual signs. An infant or child who appears happy, is prepared to play, eat, drink and take an interest in the surroundings will usually have only mild or mild-to-moderate obstruction. Caution! Watch closely! With progression of respiratory obstruction, the child may now develop more obvious chest wall retraction, use of accessory respiratory muscles, increasing heart rate and respiratory rate and an appearance of being worried and preoccupied. She may begin to appear tired and may sleep for periods of time. Clinical scoring systems are of little value. Blood gases are not of value; oximetry may warn of progressive hypoxia but decisions should not be made on oximetry alone. Whilst many children reach this stage and then go on to improve, facilities for intubation should be immediately available. If the child appears to become more and more tired, with shorter periods of sleep or no sleep, proceed to elective intubation. Act now! Intubate! Occasionally the warning signs described above will not be recognised or a child may be brought to the hospital with advanced upper airway obstruction. There may be restlessness, agitation, irrational behaviour, decreased conscious level and hypotonia. Respiratory efforts may be obviously diminishing. Cyanosis or extreme pallor may be present. Respiratory failure is now present and circulatory collapse imminent. Intubation is now urgently required.

adequate observation, and by causing crying and distress, worsens airway obstruction in many children. All who use it should recognise its limitations and dangers. Is oxygen therapy dangerous in upper airway obstruction? It has traditionally been taught that additional oxygen masks the severity of upper airway obstruction by preventing cyanosis and hypoxic agitation. Obvious cyanosis is usually seen only once airway obstruction is profound. Pulse oximetry has shown little correlation between oxygen saturation and the degree of obstruction. Some children with mild or moderate airway obstruction show marked oxygen desaturation and some children with severe airway obstruction show only mild or moderate oxygen desaturation. Correcting hypoxia does not reduce respiratory drive in children with acute upper airway obstruction. It is obvious that giving oxygen to a profoundly obstructed child can only make subsequent resuscitation safer and more likely to succeed. In summary, then, whilst oxygen therapy is unnecessary for most children with mild to moderate upper airway obstruction, it is necessary for those with severe obstruction. As a corollary any child Table

The traditional use of ‘steam’ or ‘mist’ (fine suspended water droplets) for children with croup is still widespread. In hospital practice, a warm water fog is produced by an electric humidifier (previously by boiling water with a steam kettle) or a cold water fog is produced by a nebuliser. Despite lack of scientific evidence of efficacy, the treatment is still considered indispensable by many. The anecdotal benefits of sitting with a child in a steamed-up bathroom at home, may have more to do with close proximity of a reassuring parent than with the warm water fog itself. Mist tent therapy should not be used. It is potentially dangerous as it hampers

decades

in acute

upper

airway

obstruction

Diphtheria is the major cause of severe acute upper airway obstruction. Antiserum treatment is well established. ‘Acute simple laryngitis’, ‘spasmodic croup’ and croup associated with rickets have long been recognised.

1930s

Diphtheria begins to decline immunisation is introduced. Tracheotomy where needed, resort’.

as active is done

as a ‘last

1940s

Diphtheria is now rare in countries with effective active immunisation programmes. Antibiotics are increasingly used for various forms of acute upper airway obstruction.

1950s

Acute epiglottitis. previously called ‘oedematous laryngitis’, is increasingly recognised as a separate entity. Tracheotomy, where needed, is still only done a ‘last resort’.

Controversial questions Should ‘mist’ be used for laryngotracheitis?

Seven

1920s

Except ions When a clinical diagnosis of early acute epiglottitis or diphtheria is made, it is appropriate to make immediate arrangements for elective intubation, as rapid progression to severe obstruction is usually seen in these conditions.

2

as

1960s

Corticosteroids are increasingly used. The need for tracheotomy is now anticipated and done earlier under better conditions. Virus isolation demonstrates the place of viruses in laryngotracheitis.

1970s

The use of racemic adrenaline increases, especially in the US. Endotracheal intubation is increasingly alternative to tracheotomy.

1980s

used

as

Mist tent therapy persists despite lack of evidence of efficacy. Acute epiglottitis becomes more common; it continues to cause deaths. Viral supraglottitis is described. Diphtheria continues to occur in poorly immunised countries. Haemophilus vaccines offer future hopes for a reduction in the incidence of epiglottitis.

ACUTE UPPER AIRWAY

recognised as requiring oxygen also requires very close observation. What is the place of nebulised adrenaline in managing acute laryngotracheitis?

Nebulised adrenaline (335 ml adrenaline 1: 1000 BP) will often produce marked though transient improvement in moderate or severe croup. The effect lasts 20-45 min and even repeated administration does not reduce the length of the illness or reduce the likelihood of the need for mechanical relief of airway obstruction. Nevertheless, this short-term improvement can be of value in facilitating interhospital transport or delaying the need for intubation until more experienced personnel arrive. Nebulised adrenaline should not be used in children with mild airway obstruction. It should only be used in well-equipped accident and emergency departments or intensive care units with pulse oximetry, ECG monitoring and, most importantly, close observation by skilled personnel. Are corticosteroids obstruction?

qf value in upper airway

The use of corticosteroids in acute laryngotracheitis remains controversial despite recent studies suggesting marginal benefits. Many studies have been uninterpretable due to poor design, or have shown no difference in treated and untreated groups. By combining all available interpretable studies into a ‘meta-analysis’ it has been possible to demonstrate some benefit from corticosteroids. Further large, well-designed studies are needed to elucidate whether particular groups of children with croup benefit substantially from corticosteroids and whether drug therapy has significant disadvantages. Corticosteroids cannot be recommended in the routine management of croup. The marginal benefit from corticosteroids might justify

palate epiglottis hyoid

false

cords

true

cords

sub lottic trac R ea

midtrachea

2-Magnified

normal

lateral

airway.

21

their use in severe croup when intubation is being considered but has been deferred because of a good response to nebulised adrenaline, in croup in the child known to have subglottic narrowing, for those who previously required an artificial airway for croup, and prior to extubation of a child with croup where difficulties were anticipated (for instance due to initial traumatic intubation). While there are no adequate studies of the use of corticosteroids in upper airway obstruction associated with infectious mononucleosis, this condition tends to improve rapidly after 12-24 h whether or not corticosteroids are given. There is no justification for using corticosteroids in spasmodic croup, bacterial tracheitis or epiglottitis. Initial treatment of angioedema should be with adrenaline, and the value of corticosteroids is secondary.

Does the lateral airway X-ray have a place in management?

There are numerous anecdotes of benefits obtained from lateral airway X-rays. The suspected clinical diagnosis is usually confirmed and occasionally an unsuspected diagnosis is revealed. With a good quality X-ray, subglottic narrowing, epiglottitis, retropharyngeal abscess and radio-opaque foreign bodies can usually be recognised. However, there are also anecdotes of sudden collapse in the X-ray department, incorrect diagnosis and unnecessary delays in treatment. Lateral airway X-rays should not be done where severe obstruction is present. Since posturing the child for the X-ray may precipitate complete airway obstruction. When intubation is needed, diagnosis can be made by direct examination of the upper airway at the time of laryngeal intubation. With lesser degrees of obstruction, lateral airway X-rays can be of value if good quality X-rays are available with safety and without delay and if the X-rays can be skilfully interpreted. The child must always be accompanied to and from the X-ray department by someone skilled in resuscitation with appropriate equipment at hand. Figures 2-6 show lateral airway X-ray appearances in a variety of conditions.

bone

arycpiglottic

Fig.

OBSTRUCTION

folds

What is the role of endoscopy in managing acute upper airwqv obstruction?

In most children where intubation is needed an anaesthetist can make the diagnosis using a conventional laryngoscope and carry out intubation at the same time. Flexible endoscopy also is satisfactory for this assessment and can occasionally be useful to facilitate intubation. If subglottic pathology is found on laryngoscopy, bronchoscopy is both unnecessary and may cause further subglottic pathology. Bronchoscopy will be required where a tracheal or bronchial foreign body is present or suspected and on these occasions, a rigid

22

CURRENT

PAEDIATRICS

mandibula taKJue

roml

Dotote

huge c&strxting

epiglottis

6 Fig.

3A-

-Large

obstructing

tonsil

(plain).

Fig.

36-

-Large

obstructing

tonsil

(labelled).

wlate distended phfwx

obscured upper t roct lea

tmchea

6 Fig. 4A-Epiglottitis

I (plain).

Fig.

I (labelled).

4B-Epiglottitis

ACUTE

tonsil swollen epiglottis hyoid bona obscured uppar trachea

UPPER

AIRWAY

OBSTRUCTION

23

inexperienced use of a laryngoscope and appropriately sized orotracheal tube would be preferable to an inexperienced attempt at tracheotomy or an attempt to maintain ventilation with a bag and mask. Intubation should only be attempted after oxygenation with face mask oxygen. Recently, cricothyrotomy kits for children have become available. As yet, there is little recorded experience of the use of such kits. What should be taught as first aidfor choking?

trachea

Fig. 4C-Epiglottitis ‘thumb-tip’ or ‘hump’

II. These X-rays demonstrate seen in acute epiglottitis.

the typical

bronchoscope with fiberoptic lighting and high quality optics should be used. Rigid bronchoscopy permits effective suctioning, use of grasping instruments to remove the foreign body and allows simultaneous ventilation. What is the best emergency airway for the nonanaesthetist? If it is apparent that the child desperately requires intubation and an anaesthetist is unavailable, even the

First-aid is far removed from medical practice but paediatricians should know what is advocated by first-aid authorities and may even have to carry out first-aid themselves. Lateral chest thrusts and/or backblows are often advocated as the first measures in a child who appears to be apnoeic from choking. Looking in the mouth and ‘finger-sweeps’ of the lower pharynx follow, then finally closed chest cardiac massage if all other measures are unsuccessful. A major controversy has been whether the Heimlich manoeuvre (abrupt upper abdominal compression) is too dangerous because of the risk of liver trauma. Most now accept the Heimlich manoeuvre as a reasonable last resort in an individual who will otherwise die if the choking material cannot be dislodged. The efficacy of any of the methods is unknown but unlikely to be great. It is not logical to expect too much of first-aid in situations which would challenge a skilled operator with laryngoscope in one hand, tube and McGill forceps in the other.

palate phorw mandible

larynx vertebral bodies

gmssly wid’ med pnvertebfal tiss

tractua

Fig.

5A-Retropharyngeal

abcess

(plain).

Fig.

SB-Retropharyngeal

abcess

(labelled).

ues

24

CURRENT

PAEDIATRICS

Management of acute laryngotracheitis When to manage at home? The child with mild croup can usually be managed at home if the stridor and retractions disappear at rest and hydration is adequate. The parents should be advised to observe the child and to proceed to hospital if increased stridor, retractions or agitation develop.

1 Acute laryngotracheltis? 1-1

-

I

When to admit to hospital? Children with moderate croup have persistent stridor and retraction and may develop progressive airway obstruction, particularly during the night. In addition to severity, factors such as time of day and distance from hospital, young age (< 12 months) and parents’ ability to cope, are to be considered in the decision to manage the child at home or admit to hospital. If oral intake and hydration are inadequate, intravenous fluids are indicated. Hospital management

I

I

see Taxt

+I

I

IneffectIverespiration gaspingor unconscious

I

1I

1 1. 6ag & face mask oxygen, wM4tion 2. ImmfxMe

1

I I

prqarafionto&bate

3. Summon hospital anaesthetk

Adequate respiratory eff Ott/gasexchange

I

I

I

team

I

I

The majority of children admitted to hospital with moderate croup need careful observation and no other therapy. The reason for admission is to anticipate deterioration and to identify those few children who require intervention. A logical plan of management is presented in Figure 7. Management of other conditions As the majority of children with acute epiglottitis rapidly progress to profound airway obstruction, it is safest to intubate all children with this condition. When acute epiglottitis is suspected clinically, urgent arrangements must be made for an experienced anaesthetist to proceed to direct laryngoscopy and elective intubation in the operating theatre under inhalational general anaesthetic. Meanwhile the child should not be disturbed or upset, should be allowed to stay with his or her parents, and remain under close observation with resuscitation equipment and experienced staff at hand. Intravenous access, blood tests and antibiotics are deferred until after the airway has been secured. If epiglottitis is confirmed at laryngoscopy, a blood culture and swab of the epiglottitis should be collected. The local pattern of Haemophilus influenzae antibiotic sensitivity will determine the most appropriate antibiotic. We use cefotaxime as there is resistance both to ampicillin and chloramphenicol. We use rifampicin both in the child and the family to prevent further development of invasive Haemophilus influenzae disease. A suspected foreign body causing severe upper airway obstruction requires urgent rigid bronchoscopy under general anaesthesia. If the child is unconscious or making feeble respiratory effort and expulsion manoeuvres have not been effective, then it may be

1. Trial nsbulised

adrenaline

2. Alert ho&?ai

anaesthetic

@bservation team

& intensive care ward 3. Mask oxygen it tolerated 4. Do not IqseVdisturb

chikt

I

No Improvement? I

+ Directlaryngoscqy

&

elective intubation in qerating theatre under inhalational

1. Pos@meintuh&m 2. tntensivefc?

r&oumjd8tefiorafion

generalanaestheti Management

plan.

possible to intubate the trachea permitting ventilation around the foreign body. Severe airway obstruction caused by tonsillomegaly can be managed by a nasopharyngeal tube until the inflammation resolves and intravenous penicillin is indicated for severe cases due to Streptococcus pyogenes. Quinsy and retropharyngeal abscess are managed by surgical drainage and intravenous antibiotics to cover oral pathogens. Treatment of diphtheria must include antitoxin, penicillin and later active immunisation. Tracheostomy is usually

ACUTE UPPER AIRWAY Table

distended pharynx

3

Summary

Therapy

mild

observation

laryngotracheitis

laryngotracheitis

_c_

Fig. 6-Subgottic

narrowing

normal mid-trachea

in croup.

acute

Management qf’ the intuhated child Following endotracheal intubation, the child must be nursed in an intensive care unit. After emerging from the general anaesthetic, most children can breathe spontaneously through the endotracheal tube. The inspired air must be humidified, supplemental oxygen may be needed and the tube suctioned regularly to prevent tube obstruction by thick secretions. The arms should be splinted and light sedation may be necessary to prevent self extubation. A nasogastric tube should be inserted and used for nutrition once the child is stable. In acute laryngotracheitis, extubation can be attempted when the child is afebrile and well, the secretions have diminished, sufficient time has passed for the croup to resolve (usually 4-5 days) and a leak has developed around the tube either apparent during coughing or with positive pressure. In acute epiglottitis, extubation can usually be performed after 12-24 h when the fever has resolved, the child appears well and can swallow. Antibiotics are continued for 5 days.

usually no therapy needed may require nebulised adrenaline elective intubation (preceded by minimal disturbance) intravenous antibiotics

tracheitis

foreign

required for laryngeal diphtheria as the obstruction persists for some weeks.

croup

epiglottitis

bacterial

usually require intubation antibiotics to treat Staph. aureus & H. influenzae removal by rigid bronchoscopy

body

tonsillar

antibiotics if bacterial cause steriods unproven in EBV infection occasionally require nasopharyngeal tube

obstruction

surgical penicillin

quinsy retropharyngeal

abscess

angioneurotic

drainage

surgical drainage antibiotics antitoxin & penicillm usually require intubation/ tracheostomy

diphtheria

acute

mist

close observation oxygen if desaturated + / ~ nebulised adrenaline may require intubation

narrow, blurred subglottlc trachea spasmodic

at home

admission to hospital observation no evidence to support steroids unnecessary

laryngotracheitis

severe Y

of therapies

Diagnosis

moderate

25

OBSTRUCTION

oedema

subcutaneous

adrenaline

Further reading I. Cherry JD. The treatment of croup: Continued controversy due to failure of recognition of historic, ecologic, etiologic and clinical perspectives. [Editorial]. J Pediatr 1979; 94: 352-4. 2. Couriel JM. Management of croup. Arch Dis Childhood 1988; 63: 1305-S. 3. Kairys SW, Olmstead BA, O’Connor GT. Steroid Treatment of Laryngotracheitis: A Meta-Analysis of the Evidence From Randomized Trials. Pediatrics 1989; 83: 683393. 4. Kilham H, Gillis J, Benjamin B. Severe Upper Airway Obstruction. Pediatr Clin North Amer 1987; 34: l-14. 5. Smith DS. Corticosteroids in croup: A chink in the ivory tower? [Editorial]. J Pediatr 1989; 115: 256-7.