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Transcript
Diseases of Respiratory tract
Upper respiratory tract diseases
Acute nasopharyngitis:- Its also called
common cold.
--it’s the most common infectious condition in
children.
--its more extensive in children than in adults. often
with involvement of Para nasal sinuses, middle ear
&naso pharynx.
Acute nasopharyngitis
Etiology:•
•
•
•
Its caused mainly by more than 200 serologically different viruses.
1/3 of cases due to Rhinoviruses.
10% of cases due to corona viruses.
Other causes are RSV, influenza viruses,parainfluenza and
adenoviruses.
• Children have an average of 5-8 infections per year of naso
pharyngitis.and majority during first 2 years of life.
Pathology:• First changes are edema &vasodilatation in the sub mucosa,
mononuclear cells infiltrate. within 1-2 days become poly morph
nuclear cells.
Acute nasopharyngitis
• In moderate to sever infection, the superficial epithelial
cells separate and slough. There is profuse production of
mucus, at first it is thin later become thick &purulent.
• CLINICAL FEATURES:
• Common cold is more sever in young children than in
older children and adult.
• Initial manifestations in infants are sudden onset of
fever,irritability,restlessness and sneezing.
• Nasal discharge lead to nasal obstruction interfere with
nursing.
Cough is associated with 30% of cases and usually
begins after the onset of nasal symptoms.
Acute nasopharyngitis
• During the first 2-3 days the ear drum become
congested &fluid may be noted behind the drum.
• Few infants may vomit &some have diarrhea.
• Febrile phase lasts from few hours to 3 days.
• In older children the initial symptoms are dryness and
irritation in the nose & pharynx with sore throat. followed
by sneezing, chilly sensation, muscular pain, thin nasal
discharge and low grade fever.
• Nasal obstruction lead to mouth breathing which
increase the sensation of soreness.
• The acute phase last for 2-4 days.
Acute naso pharyngitis
COMPLICATIONS:
1- Otitis media is the most common complication
seen in 5-30% of cases.
2- Para nasal sinusitis.
3- Common cold is frequent trigger for asthma.
4- Involvement of lower respiratory tract like
Laryngotracheobronchitis, bronchiolitis,and
pneumonia.
.
Acute nasopharyngitis
Treatment :
• There is no specific therapy.
• Antibiotics not affect the course of illness or reduce the incidence of
bacterial complications.
• Bed rest is recommended.
• Acetaminophen (paracitol)is helpful in reducing fever ,irritability,
malaise for the first 1-2 days.
• Aspirin should not be given (risk of Reye syndrome).
• Most of the distress is due to nasal obstruction. so relieve
obstruction by
• 1- instillation of sterile saline(normal saline ) nasal drops is effective.
• 2- phenylephrine (nasal drop ) in 0.25%.nasal drops administered
15-20 min before feeding & at bed time in 1-2 drops in each nostril.
Acute nasopharyngitis
• No medication instilled in to the nose should be
used more than 4-5 days. due to chemical
irritation &induce nasal congestion.
• 3- Other topical adrenergic agents such as
xylometazoline or oxy metazoline are available
as either intranasal drops or nasal sprays.
• 4- Highly humidified environment with vaporizer
prevent drying of secretion.
• 5- Plenty of fluid given orally.
Acute nasopharyngitis
• Rhinorrhea can treated with first generation
antihistamine or topical anticholiergic agents.
• Cough suppression is not necessary in patients
with colds. Cough in some patients appears to
be due to URT irritation associated with
postnasal drip this can be treated with
antihistamine.
• In other patients, cough may be a result of virus
induced reactive airway diseases and they
should be treated with bronchodilator therapy.
Acute pharyngitis
• Acute pharyngitis refers to all acute infections of
pharynx (including tonsillitis &pharyngotonsillitis
the disease is un common under 1 year of age.
the incidence peak 4-7 year but continue
throughout later child hood &adult life.
Etiology:• Commonly caused by viruses.
• Group A-B hemolytic streptococcus is the most
important bacterial cause ,it accounts for about
15% of cases. other bacteria may proliferate
during viral infections.
Acute pharyngitis
CLINICAL FEATURES:• IN streptococcal pharyngitis ;the age of patient is 515 years.
• The disease start suddenly with high grade fever (over
38 c) associated with sore throat &difficulty in
swallowing.
• There is redness,odema,and exudates of the pharynx.
the tonsil is also enlarged with exudates.
• The soft palate show hyperemia,odema&punctate
hemorrhage.
• The patient may develops tenderness of anterior cervical
lymph nodes.
Acute pharyngitis
• In viral pharyngitis the onset of disease
is gradual, it effected all age groups.
• The patients develop low grade fever
,redness of the pharynx with
cough,hoarsness of voice ,conjunctivitis
and watery nasal discharge.
• In bacterial &viral pharyngitis older
children complain head ache, abdominal
pain and vomiting.
Acute pharyngitis
Adeno virus pharyngitis may be associated with
conjunctivitis and fever.Coxsachie virus pharyngitis may
produce small grayish vesicles and punched out ulcers
in the posterior pharynx ( herpangina ).
In EBV pharyngitis there may be prominent tonsillar
enlargement with exudates.
Diagnosis :1- rapid
detection method for streptococcal antigen. Which
is very specific in 80-85% of cases.
2- throat or pharyngeal swab for culture.
3- WBC elevated.
Acute pharyngitis
COMPLICATIONS:1- otitis media.
2- peritonsillar abscess.
3- sinusitis.
4- meningitis (rare ).
5- acute glomerulonephritis.
6- Rheumatic fever (with streptococcal infection).
7-mesentric adenitis.
Complications are low with viral infections.
Acute pharyngitis
TREATMENT:• The use of antibiotics should be guided by the result of antigen
detection or culture.
• In viral pharyngitis no need for antibiotics, only supportive treatment.
• Streptococcal pharyngitis is best treated orally with penicillin V (125250 mg ) three times daily for 10 days.
• Other line of treatment is single injection intra muscularly of
benzathine penicillin or abenzathine-procaine penicillin G
combination. as single injection.
• If patient allergic to penicillin the alternative is erythromycin( 40 mg/
kg/ day )for 10 days.
• Oral amoxicillin (50 mg /kg /day ) for 6 days is also effective.
Acute pharyngitis
Acute infection of larynx and
trachea
• Its of great importance in infants &young
children because their air ways are small
predisposing them to greater narrowing.
• CROUP is term used to describe a relatively
acute infections characterized by brassy or
barking cough which may or may not
accompanied by inspiratory stridor,hoarsness of
voice and sign of respiratory distress due to
varying degree of laryngeal obstruction.
Acute infection of larynx and
trachea
STRIDOR is a harsh, high pitched sound usually inspiratory produced
by turbulent air flow and it is a sign of upper air ways obstruction.
Acute infectious upper airways obstruction :Etiology :Viral agents account for most cases. the exceptions are diphtheria ,
bacterial tracheitis,and epiglottitis.
The parainfluenza viruses ( type 1,2,3,) accounts for 75% of cases.
other include influenza A and B,adeno virus, RSV,and measles virus.
Most patients with croup are between 3 month and 5 years of age. The
incidence of croup is higher in males. and it occur most commonly
during winter. about 15% of patients have family history of croup.
Recurrence are frequent from 3-6 years of age and decrease with
growth of the airway.
Acute infection of larynx and
trachea
Clinical classifications of acute infectious upper air way obstruction :1- Laryngotracheobronchitis (Croup ).
2- Acute epiglottitis.
3- Acute infectious laryngitis.
4- spasmodic croup
5- Bacterial tracheitis.
6- Diphtheritic croup.
Laryngotracheobronchitis :- Clinical manifestations.
It is the most common form of acute upper respiratory obstruction. It
involves the glottic and subglottic regions of larynx. Most patients
have rhinorrhea, mild cough, and low grade fever for 1-3 days
before the symptoms of croup become apparent. then the child
develops barking cough, hoarseness and inspiratory stridor.
Laryngotracheobronchitis
CLINICAL FEATURES:The symptoms are worse at night.aggitation and crying
aggravate the symptoms also. the child prefers to sit up
or be held up right. older children usually are not
seriously ill. some times the disease may progress to
increase respiratory rate, nasal flaring with sub costal
and intercostal retraction. Continuous Stridor may
develops. with sever obstruction there is air hunger,
restlessness, increase Stridor, decrease air exchange
with sever hypoxia which may cause death.
Diagnosis :- depends on clinical history. radiograph of the
neck may show typical subglottic narrowing of STEEPLE
SIGN of croup on P.A view.
croup
Acute epiglottitis
• Its lethal condition, caused by bacterial infection ( Haemophilus
influenza type b ).its occur in children 2-7 years. Male to female ratio
3:2.
• It characterized by an acute fulminating course of high fever ,sore
throat,dyspnea, rapidly progressive respiratory obstruction.
• Within a matter of hours, the patient appears toxic, swallowing is
difficult, and breathing is labored. Drooling from the mouth is usually
present and the neck is hyper extended. the child may assume the
tripod position sitting up right and leaning forward with the mouth
open.
• Stridor is a late finding and suggests near complete air way
obstruction.
• The barking cough typical of croup is rare. usually no other family
members are ill with respiratory symptoms. Complete obstruction of
the air way may ensue unless adequate treatment is provided.
Acute epiglottitis
DIAGNOSIS:- lateral neck x-ray may show enlarged epiglottis( thumb-print sign).
- Direct examination or direct laryngoscope of larynx may show a
cherry red epiglottis (supraglottis )but this not recommended
because it may precipitate laryngeal spasm.
ACUTE INFECTIOUS LARYNGITIS
• Almost all cases are caused by viruses. the onset usually
characterized by URTI then sore throat ,cough and hoarseness
appear. the illness generally mild, respiratory distress is unusual
except in infant.
• In sever cases hoarseness is marked with Stridor,
dyspnea,aggitation and air hunger.
• Laryngoscope show inflammation of vocal cord &subglottic tissue
the principle site of obstruction is subglottic area.
Acute epiglotittis
Spasmodic croup
Occurs most often in children 1-3 yr of age. it is
clinically similar to acute
laryngotracheobronchitis.except the history of
viral prodrome and fever in the patient and
family are absent.
The cause is viral in some cases but allergic and
psychological factors important in others.
It occurs most commonly at night or evening.
It begins with sudden onset that preceded by mild
coryza and hoarseness. the child awake with
barking cough, noisy inspiration, respiratory
distress and appears anxious and frightened.
Acute spasmodic croup
• The patient is usually a febrile. The severity of
symptoms diminished within several hours and
the following day the patient appears well except
for slight hoarseness and cough. similar but less
sever attacks may occur for another nights.
• Laryngoscopy reveals pale, watery edema with
preservation of the epithelium.
Acute infection of the larynx
Differential Diagnosis:1- the four syndromes above should be differentiated from
each other.
2- bacterial tracheitis.
3- diphtheritic croup.
4- measles croup.
5- foreign body aspiration.
6- retropharyngeal or peritonsillar abscess.
7- extrinsic compression of the air ways.
8-intraluminal obstruction from mass (laryngeal papilloma)
9-congenital anomalies of larynx like Laryngomalacia.
Acute infection of larynx
TREATMENT :• Treatment of, acute infectious laryngitis,
laryngotracheobrochitis ,and spasmodic
laryngitis include :• Most patients can be safely & effectively treated
at home .
• Use of steam from hot shower or bath in closed
bathroom. or cold steam from nebulizer , or hot
steam from vaporizer, may relieve the
symptoms.
Treatment of croup
The followings are indications of admission to
hospital in any child with croup:1- actual or suspected epiglottitis.
2- progressive Stridor or sever Stridor at rest.
3- patient with croup and temperature over 39 c.
4- respiratory distress.
5- cyanosis and pallor .
6- hypoxia & restless.
7- impaired consciousness.
8- toxic appearing child.
Treatment of croup
At hospital the following steps in managements may be required.
1- patient should be placed in atmosphere of high cold humidity .
2- monitoring respiratory rate & any sign of respiratory distress.
3- I.V fluid should be given to reduce insensible water loss from tachypnea in
moderate to sever respiratory distress.
4- sedative usually contraindicated.
5- oxygen should be administered in moderate to sever respiratory distress.
6- expectorant, bronchodilator & anti histamine are not helpful.
7- the use of corticosteroids is effective in treatment of viral croup.
corticosteroids decrease the edema in the laryngeal mucosa through their
anti inflammatory action. oral dexamethasone is effective in a dose of 0.15
mg/ kg.
8- nebulizer of racemic epinephrine for moderate or sever croup, It decrease
the laryngeal mucosal edema. The dose is 0.25-0.75 ml of 2.25% racemic
epinephrine in 3 ml of normal saline.
9- if there is deterioration of the condition and increase respiratory distress
despite these steps so arrange for endotracheal intubation or tracheostomy.
Treatment of acute epiglottitis
1-In acute epiglottitis the essential steps is
establishing an air way by nasotracheal
intubations or tracheostomy.
2- Antibiotics , ceftriaxone 100 mg / kg / day .or
cefotaxime. or ampicillin 200 mg /kg /day&
chloramphinicol 100 mg /kg /day. should be
given I.V. for 7-10 days.
3- oxygen should be given .
4- corticosteroid not effective.
5- Racemic epinephrine is not effective.
Bacterial Tracheitis
• Bacterial Tracheitis :-its acute bacterial
infection of trachea, commonly caused by
Staph. Aureus .
• Most patients are less than 3 years age.
• Almost always follows an viral respiratory
infection. so it may be considered a
bacterial complication of a viral disease.
• Its life threaten condition & requires
prompt treatment.
Bacterial Tracheitis
Clinical Manifestations :• After viral URTI patient develops barking cough, high fever,
gradually worsening inspiratory stridor, copious thick purulent
discharge, toxic appearance. no dysphagia and no drooling .
• The usual treatment of croup is ineffective.
TREATMENT:1- Antibiotics against Staphylococcus like cloxacillin, methicillin, third
generation cephalosporin or vancomycin.
2- endotracheal intubation or tracheostomy.
3- oxygen
4- suspicion of bacterial tracheitis in any patient with croup not
responding to usual treatment.
Acute bronchiolitis
• Its common disease of lower respiratory tract.
resulting from inflammatory obstruction of small
airways.
• It occur during first 2 years of life, commonly
from 2 month – 2 years, with peak at age of 6
month. incidence is higher in spring and winter.
• Etiology :• Its viral illness, respiratory syncytial virus ( RSV )
• is commonest cause accounting more than 50%
of cases. other viruses includes, parainfluenzae,
Adeno, influenza. Rarely by Mycoplasma.
Acute bronchiolitis
• Pathophysiology :• Bronchiolar obstruction is due to edema,& accumulation
of mucus & cellular debris & by invasion of small
bronchial tree by viruses.
• Clinical manifestations :• It starts as mild URTI with serous nasal discharge &
sneezing. these symptoms usually lasts several hours
accompanied by fever 38.5 -39 c & diminished appetite.
then gradual development of respiratory distress
characterized by cough, dyspnea, wheeze,& irritability.
• Apnea may be more prominent than wheezing early in
the course of the disease in very young infants.
Acute bronchiolitis
• On examination there is tachypnea, cyanosis
may be present, sub costal &intercostal
recession, flaring of alae nasi.liver & spleen may
be palpable due to hyper inflation of lung.
Auscultation may reveal wide spread fine
cripitation,prolong expiratory phase with wheeze
(most prominent sign).
• Diagnosis:- It is mainly clinical
• 1-CXR show hyperinflation of lung&increase AP
diameter. some times segmental consolidation.
• 2-WBC &differential counts are normal.
Acute bronchiolitis
• Diagnosis :• 3- Viral testing :- viruses may be demonstrated in
nasopharyngeal secretions by culture or by
immunofluresence technique.
• D.Diagnosis:• 1- bronchial asthma.
• 2- congestive heart failure.
• 3- foreign body in the trachea.
• 4- pertusis.
• 5- cystic fibrosis.
• 6- bacterial bronchopneumonia.
• 7- obstructive emphysema.
Acute bronchiolitis
• Treatment :• Since its viral infection, treatment is supportive,
infant with respiratory distress should be
admitted to hospital and should be placed in
atmosphere of cold humidified oxygen.
• Placing the patient sitting at 30-40 degree angle
or head and chest slightly elevated.
• Sedative should be avoided.
• I.V.F is indicated in case of sever tachypnea
which interfere with feeding .
Acute bronchiolitis
• Ribavirin is anti viral agent administered
by aerosol. used for infants with congenital
heart disease or chronic lung disease with
bronchiolitis.
• Antibiotics have no therapeutic value.
• Corticosteroid not indicated.
• Bronchodilators may be beneficial.
• Nebulizer of epinephrine may be effective.
Bronchiolitis
Pneumonia
• Pneumonia is an inflammation of the parenchyma of the lungs. It is
also defined as consolidation of alveolar tissues which could be
lobar, lobular or segmental.
• Bronchopneumonia is involvement of the bronchi & the surrounding
alveolar tissue which is more profuse & bilateral.
• Etiology :• Usually due to viruses ( 70 % ).most common virus RSV, others
parainfluenzae, Adeno virus, entero, influenza viruses.
• Bacteria ( 10- 30 % ).most common bacteria is pneumococcus.other
bacteria streptococci, staph.aureous ( during first year ),
Haemophilus influenzae,klebsiella, pseudomonas.
• Fungal infection.
• Mycoplasma infections: Mycoplasma pneumoniae
• Other causes rikettsia, parasites, chemical and aspiration of food,
gastric acid or hydrocarbons.
Pneumonia
•
•
•
•
Routes of infection in pneumonia:1- haematogenous route.
2- respiratory route
3- Aspiration route commonly in
unconscious patient, patient with hiatus
hernia, reflux esophagitis,
tracheoesophagial fistula, achalasia,
cerebral palsy, epilepsy.
Pneumonia
• Clinical features :• Viral and bacterial pneumonias are often preceded by several days
of symptoms of an upper respiratory tract infections like rhinitis and
cough.
• In viral pneumonia: fever is usually present, temperature is
generally lower than in bacterial pneumonia.
• Tachypnea is the most consistent clinical manifestations
• Increase work of breathing accompanied by intercostal,subcostal
and suprasternal retractions.
• Nasal flaring and use of accessory muscle is common.
• Sever infection may associated with cyanosis.
• Auscultation of the chest may reveal crackles and wheezing.
Pneumonia
•
•
•
•
•
Bacterial pneumonia: In older children a brief upper respiratory tract illness
is followed by sudden onset of chills and high fever accompanied by
drowsiness. this followed by rapid respiration, dry hacking cough and chest
pain.Circum oral cyanosis may be observed.
Physical findings depend on the stage of pneumonia. Early in the course of
illness scattered crackles and rhonchi are heard over affected lung field.
With the development of increasing consolidation dullness on percussions is
noted, with increase vocal fremitus and resonance. bronchial breathing
heard over affected lobe.
In infant there may be a prodrome of upper respiratory tract infection and
diminished appetite followed by sudden onset of high fever and respiratory
distress which manifested by grunting, nasal flaring ,retractions of the supra
clavicular,intercostal and sub costal areas.Tachypnea and often cyanosis
are also present.
Some infants may have associated vomiting, anorexia and diarrhea.
pneumonia
• Clinical manifestations:• Rapid progression of symptoms is characteristic of sever bacterial
pneumonia. Lobar consolidation, large pleural effusion and high
fever are also suggestive of bacterial etiology.
• Abdominal pain is common in lower lobe pneumonia and nuchal
rigidity may be prominent in right upper lobe pneumonia.
• Streptococcus pneumoniae infection is often resulting in focal lobar
involvement.
• Group A streptococcus infection result in interstitial pneumonia.
• Staphylococcus aureus pneumonia is manifested by confluent
bronchopneumonia which is often unilateral and characterized by
the presence of areas of cavitations of lung parenchyma resulting in
pneumatoceles,empyema and broncho pulmonary fistula.
pneumonia
• Clinical manifestations:• Mycoplasma pneumonia: It is a major cause of
respiratory infection in school- aged children and young
adults. The disease is characterized by gradual onset of
head ache, malaise, fever and sore throat followed by
progression of lower respiratory symptoms including
hoarseness and cough, The cough is initially non
productive but older children may produce a frothy, white
sputum. With progress of disease the cough becomes
troublesome and the patient become dyspneic.On
examination fine crackles is a prominent sign.
Pneumonia
•
•
•
•
•
•
•
•
•
•
Diagnosis:Diagnosis mainly clinical.
1- chest x- ray
(viral pneumonia is characterized by hyper inflation with bilateral interstitial
infiltration. lobar consolidation is seen with pneumococcal pneumonia.)
2- White blood cell count .can be useful in differentiating viral from bacterial
pneumonia. in viral the WBC count is normal or slightly elevated with
lymphocyte predominance. While in bacterial pneumonia the WBC is
elevated (15000- 40000 /mm3.)and mainly of granulocytes.
3- blood culture.
4- sputum for gram stain and culture.
5- virological study by culture &florescent antibody technique.
6- in case of Mycoplasma pneumonia cold agglutinin or specific IgG or IgM
anti Mycoplasma antibody.
7- in case of pleural effusion aspirate pleural fluid for gram stain and culture
also for acid fast bacilli.
Pneumonia
•
•
•
•
•
•
•
Complications:A- Pulmonary complications
1- pleural effusion.
2- empyema.
3- lung abscess.
4- pneumatocele.
5- pneumothorax.
•
•
•
•
•
B- Extra pulmonary complications:1- meningitis.
2- arithritis.
3- osteomyelitis.
4- pericarditis.
Pneumonia
•
•
•
•
•
•
•
•
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TREATMENT:Depends on 1- age of patient. 2- cause.
3- severity. 4- present of complications.
Indications for admission to hospital:1-patient less than 3 month of age.
2- moderate to sever respiratory distress.
3- failure of out patient treatment.
4-immunocompromised patient.
5- neonate with congenital pneumonia.
6- staphylococcal pneumonia.
7- complications like pleural effusion, empyema.
If patient age 5-10 years with mild infection can be treated at home
with high dose of oral or paranteral antibiotics.
Pneumonia
TREATMENT:A- supportive by 1- oxygen 2- IVF. 3- antipyretic for fever.
B- specific treatment:1- for pneumococcus:- penicillin G, or third generation cephalosporin
like cefotaxime or ceftriaxone.
2- streptococcus:-penicillin G.
3- staphylococcus:- cloxacillin, methicillin, or third generation
cephalosporin, or vancomycin.
4- H. influenzae:_ third generation cephalosporin.
5- Mycoplasma:- azithromycin ,clarithromycin or Erythromycin.
6- viral pneumonia:- ribavirin for RSV.
Thoracocentesis –chest tube drainage in case of empyema or
pleural effusion.
Pneumococcal pneumonia
Staphylococcal pneumonia
Asthma
• Asthma is diffuse obstructive lung disease with :• 1- hyper reactivity of airways to variety of stimuli.
• 2- high degree of reversibility of obstructive process
which occur either spontaneously or as a result of
treatment.
• It is also known as ( reactive airway disease ) both large
(more than 2 mm ) & small (less than 2 mm ) airways
may be involved to varying degree.
• Asthma is a leading cause of chronic illness in childhood.
As many as 10-15 % of boys & 7-10% of girls may have
asthma at some time during childhood .before puberty
approximately male to female ratio 2:1 thereafter sex
incidence is equal.
Asthma
• Asthma inherited as multifactorial mode.
• Asthma may have its onset at any age.
• There are 2 main types of childhood
asthma :• 1-Recurrent wheezing in early childhood,
primarily triggered by viral infection.
• 2-Chronic asthma associated with allergy
that persists into later childhood and often
adulthood.
Asthma
The following factors associated with increased
mortality in asthma :1- sudden acute sever asthma episode.
2- chronic steroid dependant asthma.
3- under estimation of severity of illness by patient
,family ,physician lead to delay treatment.
4- under use of steroid.
5- sever a topic disease.
6- family dysfunction& stress.
Asthma
Pathophysiology :• Manifestation of air ways obstruction in asthma are due to :• 1- bronchoconstriction.
• 2- hyper secretion of mucus.3- mucosal edema 4- cellular infiltration
and
• Desquamation of epithelial and inflammatory cells.
• Various allergic & non specific stimuli in presence of hyperactive
airways initiate bronchoconstriction these include :1- inhaled allergen ( dust , pollen )
2- viral infection
3- cigarette smoke.
4- air pollutant
5- strong odor & perfume.
6- drugs ( aspirin, endomethacin, brufen, inderal )
7-cold air & exercise.
Asthma
• Following non specific stimulation or binding of allergens
to specific mast cell associated IGE ,mediators are
released from mast cell , these mediators such as
• ( histamine , leukotriene, platelet activating factors)
initiate bronchospasm, mucosal edema and immune
response. The early immune response result in
bronchoconstriction . While late immune response occur
6-8 hour later produce continue state of hyper
responsiveness with eosinophil & neutrophil infiltration.
obstruction most sever during expiration because
intrathoracic airways become smaller during expiration.
Asthma
Etiology :- asthma is complex disorder involving
1- autonomic factor
2-immunologic
3- infection
4- endocrine
5- psychological factors.
6- genetic factors.
Autonomic :- asthma may be due to abnormal B- adrenergic receptors,
or decrease in number of B- adrenergic receptors. or due to
increase cholinergic activity in the airways.
Immunological factors :- in some patient so called extrinsic or allergic
asthma the attack follow exposure to environment factors such as
pollen or dust .such patients have increase of IGE against
allergen implicated.
Asthma
• In other patient with clinically similar asthma
there is no evidence of IGE involvement , skin
test negative, IGE level is low this form of
asthma called intrinsic asthma.
• Infection :- viral infection is a triggering factor for
asthma .
• Endocrine :- asthma worsen in pregnancy also
in thyrotoxicosis but some children with asthma
improve at puberty.
Asthma
Clinical Features :- the onset may be acute or insidious.
acute episodes are most often caused by exposure to
irritants such as cold air or fumes or exposure to allergen
or drug like aspirin.
The sign & symptoms of asthma include cough which is
not productive early in the course of attack, wheezing,
Tachypnea, dyspnea, with prolong expiration & use of
accessory muscle. Cyanosis, hyperinflation of chest ,
tachycardia may be presented.
when patient in extreme respiratory distress the cardinal
sign of asthma ( wheezing ) mat be absent .shortness of
breath may be so sever that the child has difficulty in
walking & even talking.
Asthma
• Abdominal pain is common due to strenuous
use of abdominal muscle & diaphragm .
• vomiting, profuse sweating, and fatigue may
occur. low grade fever may developed due
enormous work of breathing.
• Barrel shape deformity is sign of chronic airway
obstruction of sever asthma.
• Harrison sulcus ( antero lateral depression of
thorax at insertion of diaphragm ) may be
present in chronic asthma.
Asthma
Diagnosis :- recurrent episodes of cough & wheezing specially if
aggravated by exercise, viral infection, inhaled allergen are highly
suggestive of asthma.
Laboratory evaluation :1- eosinophilia of blood & sputum occur with asthma. blood
eosinophilia of more than 200-400 cell/ mm is usual.
2- allergen skin test and RAST (radioallergo sorbent test ).
3- IGE level in blood (usually elevated in asthma.)
4- exercise testing :- treadmill running at 3-4 miles and exercise
which increase pulse rate to 180 beat/ min this elicit airways
obstruction in most patients with asthma.
• Measurement of pulmonary function before and after exercise show
decrease in peak expiratory flow rate (PER ) and forced expiratory
volume in 1 sec (FEV 1) for at least 15 % with out medications in
asthmatic patient.
Asthma
Diagnosis:_
5-
Pulmonary function test :A- peak expiratory flow rate decrease (PEFR ).
B- forced expiratory volume in 1 sec decrease (FEV1) .
C- vital capacity ( VC ) decrease.& forced vital capacity decrease.
D- residual volume ( RV ) increase.
E- total lung capacity (TLC ) increase.
6- Chest X- ray :- indications of chest x –ray in asthma include .
1- first attack of asthma to exclude other conditions.
2- fever with asthma.
3- suspicion of complications like( pneumothorax,atelectasis ).
4- tachycardia more than 160 beat/ min.
5- Tachypnea more than 60 cycle / min.
6- localized rale & ronchi.
7- decreased breath sound.
Asthma
chest x-Rays in asthma often appears to be normal. aside from
nonspecific finding of hyperinflation.
7- Blood gases and PH analysis:- during remission po2, pco2 and PH
are normal. in symptomatic period low po2 regularly found,pco2
generally low in early stages as obstruction become sever pco2
rise.PH normal in early stage then in sever cases become
acidosis.
D.DIAGNOSIS :1- infection:- like bronchiolitis, pneumonia, and tuberculosis.
2- anatomic and congenital:Like cystic fibrosis, heart failure, vascular ring ,tracheo-esophgeal
fistula, gastro-esophageal reflux.
3- Vasculitis :- like allergic aspergillosis, alveolitis.
4- Others :- foreign body inhalation, psychogenic cough.
Asthma
Treatment of asthma :- asthma therapy include :
1- Avoidance of allergens.
2- improving bronchodilators.
3- regular assessment & monitoring.
1- Avoidance of allergens.
• If history and skin test indicate reactivity to house dust
mites, or mold these allergen should be eliminated from
home. Reduce exposure to pollens. avoidance of irritants
such as tobacco smoke, fumes from kerosene heater
&strong odor. Avoidance of ice cold drinks and rapid
change in temperature & humidity.
Treatment of Asthma
2- improving bronchodilators :- it is main step in treatment of asthma.
• A- oxygen administration by mask or nasal prongs at rate of 2-3
L/min
• B- inhalation of bronchodilator aerosol ( by nebulizer ). Using B2 –
agonist like albuterol (ventolin, butadin) in a dose of 0.05-0.15 mg/kg
every 20 min for one hour until response adequate. It should be
diluted with 2-3 ml of normal saline. this medication induce airway
smooth muscle relaxation.
• C- anti cholinergic agent : e.g. ipratropium bromide is less potent
than B- agonist. It is used by inhalation usually in combination with
inhaled short act B- agonists.
• D-systemic corticosteroid like prednisolon in a dose of 1-2mg/ kg.for
5-7 days. it is usually used in moderate to sever asthma
exacerbation. it reduce the relapse and hospitalization.
Treatment of Asthma
• E- epinephrine ( adrenalin ) in a dose of 0.01mg/kg of 1:1000
concentration. given S.C it may be necessary to repeat same dose
once or twice at interval of 20 min.no more than 0.3 ml should be
given at any age.
• F-If response to epinephrine or B-agonist is not satisfactory
Theophylline ( aminophyllin ) is given in a dose of 5mg/kg/dose
administered intravenously slowly in 10- 15 min and can repeated 6
hourly.
• All these medications are used for treatment of acute asthma
symptoms ( asthma exacerbations).
• Short act inhaled B- agonist, inhaled anticholinergics,and short
course systemic steroids. are called Quick- relief medications.
• B-agonists cause bronchodilation by inducing airway smooth
muscle relaxation, reduce vascular permeability and reduce airways
edema.
Treatment of Asthma
• Adverse effects of short act B-agonist include:palpitations,tachycardia,arrhythmia,tremor
• Hypokalemia and hypoxia.
• The dose of inhaled short acting B-agonist in nebulizer is
0.15mg /kg as often as every 20 min for 3 doses only
then 0.15- 0.3 mg/kg every 1-4 hours as needed.
• 3-Regular assessment and monitoring:• Regular clinic visits every 2-4 weeks until good asthma
control is achieved.
• Peak expiratory flow (PEF) monitoring at home is
recommended once daily preferable in the morning.
• Morning to evening variation in PEF greater than 20% is
consistent with asthma.
Status Asthmaticus
Status Asthmaticus :- it is defined by increasing sever
asthma that is not responsive to drugs that is usually
effective .
Management of status Asthmaticus:1- admission to hospital preferably to an intensive care unit
for monitoring the patient carefully. Base line complete
blood picture (CBP ), serum electrolyte, analysis of
arterial blood for PO2, PCO2, PH, is indicated.
• Cardiac and respiratory score monitoring at regular
interval.
2- administration of oxygen .if there is hypercapnea ,o2
should be given continuously at rate of 2-3 L/min.
Status Asthmaticus
3- correction of dehydration : which is due to in adequate intake ,
increase insensible water loss due to Tachypnea and diuretic effect
of aminophyllin.so intra venous fluid should be given.
4- NAHCO3 1.5-2 Meq/ kg should be given every 4-6 hr if PH less than
7.3 and serum sodium less than 145 meq/l. after patient pass urine
potassium chloride should be given because ventolin cause
hypokalemia.
5- B-agonist given by nebulizer , aminophyllin 5mg/kg/dose should be
given I.V over 20 min every 6 hr. Alternatively a loading dose of
aminophyllin 5 mg/ kg given followed by continuous infusion of 0.751.25 mg/kg/hr may be given.
6- corticosteroid: hydrocortisone 10 mg /kg repeated every 6 hr,it
improve oxygenation , decrease airway obstruction & shorten the
time needs for recovery.
7- Mechanical ventilation is indicated if respiratory failure impending.
Treatment of Asthma
• Long term control of asthma or controller medications:• These medications are used daily to maintain control of asthma and
prevent asthma symptoms it include :• 1-Inhaled corticosteroids therapy.
• 2-Leukotriene- modifying agents:- these drugs alter the leukotrienes
pathway either by inhibiting production or blocking receptors binding
• eg;- Montelukast used in children more than one year of age. it is
administered once /day. Other drug is Zafirlukast which is used for
children more than five years of age. administered twice / day.
• 3- Long acting inhaled B- agonist (salmeterol ).
• 4- Sustained release Theophylline.
• 5-Cromlyn and nedocromil:- these agents can inhibit both early and
late phase components of allergic induce asthma .
• 6- Systemic corticosteroids therapy.
Asthma
Classification of Asthma:• Mild Asthma :- patients have attacks of varying
frequency less than 3 per week. not sever, respond to
bronchodilators within 1-2 days. no medications required
between attacks, good school attendance, good exercise
tolerance, no interruption of sleep, no hyperinflation of
chest, normal CXR , no increase in lung volume.
• Moderate Asthma :- symptoms are more frequent than
mild asthma, have cough and wheeze between attacks,
exercise tolerance decrease, lose sleep some nights,
require continuous bronchodilators, hyperinflation of
chest may be evident clinically and by chest X ray. lung
volume increase.
Asthma
• Sever Asthma :- daily wheeze with more
sever and more frequent exacerbations.
patient requires frequent hospitalization,
missed significant amount of school,
interrupted sleep, poor exercise
intolerance, chest deformity, needs
bronchodilators continuously and
administration of steroid regularly.
Asthma
Foreign Bodies of the Airway
• Etiology :• Most victims of foreign bodies aspiration are older infants and
toddlers. children under the age of 3 yr account for 73% of cases.
One third of aspirated objects are nuts. Fragments of carrot, dried
beans, watermelon seeds are also common.
• Clinical Manifestations :• Apositive history must never be ignored. Choking or coughing
episodes accompanied by wheezing are highly suggestive of F.B.
• Three stages of symptoms result from F.B aspiration :• 1- Initial event:- violent paroxysms of coughing, choking and
gagging.
• 2- Asymptomatic interval :- the immediate irritating symptoms
subside as the foreign body becomes lodge.
• 3- Complications :- in this stage obstruction, erosion, or infection
develops to direct attention to the presence of F.B . Complications
include fever, cough, pneumonia, atelectasis and hemoptysis.
Foreign bodies of air way
• Laryngeal F.B :- Complete obstruction of air ways may asphyxiates
the child unless immediate resuscitations done. Objects that are
partially obstructive are flat and thin causing symptoms of croup
,hoarseness, cough ,Stridor and dyspnea.
• Tracheal F.B :- choking and aspiration occur in 90% of
patients.stridor in 60% and wheezing in 50%.
• P.A and lateral neck radiographs needed for diagnosis.
• Bronchial F.B :- bronchial foreign body obstructs the exit of air from
lung during expiration, producing obstructive emphysema( air
trapping ). Air trapping is an immediate complication. Late
complication is atelectasis (it is incomplete expansion or complete
collapse of air bearing tissue ) .
• Diagnosis :- by C.X.R and Bronchoscopy.
• Treatment: - the treatment of choice for airway foreign body is
endoscopic removal with rigid instrument ( Bronchoscopy ) .