This document discusses the anatomical and physiological peculiarities of the respiratory system in children. It describes the embryological development of respiratory organs from the 3rd week of gestation through birth. There are several anatomical differences compared to adults, including smaller and narrower nasal passages, underdeveloped sinuses, and a higher located larynx. Respiratory rates are also higher in children. Examination of children with respiratory diseases involves clinical exams, laboratory/imaging tests, and evaluation of cough, sputum, and breathing patterns, which can provide clues to different conditions.

1. Anatomical and Physiological Peculiarities
of Respiratory System in Children.
Peculiarities of Embryogenesis of
Respiratory Organs and Anomalies in Their
Development.

2. Plan of the lecture
 Making up and intrauterine development of
respiratory organs.
 Peculiarities of the structure of upper
respiratory passages.
 Middle and lower respiratory passages,
peculiarities of their structure in children in
different age periods.
 Examination of children with diseases of the
respiratory system.

3. Embryogenesis of respiratory
organs
 From the 3rd
week of embryonic development begins
the formation of respiratory organs and lasts a long
time after the birth of a child.
 In the 3rd
week of embryogenesis in cervical portion
of entodermal tube appears a bulge, which grows
rapidly. In the 4th
week it divides into two parts- right
and left - the future right and left lungs. Each of them
in its turn branches up like a tree. Plain muscular
fibers and cartilages of bronchi are formed of a
mesodermal mesenchima.

4. Embryogenesis of respiratory
organs
 Canalicular phase (recanalization) lasts 16-26 weeks.
This time takes place formation of holes in bronchi,
continues development and vascularization of the
future respiratory sections of the lungs.
 Completing phase (alveolar)- period of the formation
of alveoli - begins in the 24th
week. To the moment of
the child’s birth it does not finish and formation of
alveoli continues also in postnatal period.

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6. In anatomical structure respiratory
organs are divided into:
 upper respiratory passages
(nasal cavity, pharynx,
larynx);
 middle respiratory passages
(trachea, bronchi);
 lower respiratory passages
(bronchioli, alveoli).
 In children in different age
periods are noticed
peculiarities of respiratory
organs structure.

7. Peculiarities of the structure of
upper respiratory passages:
 Nose:
 small sizes;
 nasal passages are narrow;
 in children of the first years of life is absent the lower nasal
passage (its development finishes by 4 years of age);
 mucous membrane is gentle, well vascularized, inclined to
quick edemas;
 lymph system of the nose is connected with subdural and
subarachnoidal areas, promoting generalizing infection.

8. Peculiarities of the structure of
upper respiratory passages:
 Additional sinuses:
 underdeveloped (in newborns only sinusoidal
and cribrate are in germinal state, which Rtg
are detected from 3 months);
 from 2 years of life is developing frontal and
from 6 years - the main sinuses, due to which
in children of early age never are sinusitis.

9. Peculiarities of the structure of
upper respiratory passages:
Pharynx:
is relatively short and narrow;
internal hearing passage, which opens in rhinopharynx,
is rather wide and straight and this promotes
development of medial otitis;
lymphatic ring of Pirogov-Valdeiern in newborns is
underdeveloped, cripts are absent. Due to this in the first
years of life anginas arise very seldom. By 2-3 years of
life there is intensive development of tonsils, especially
rhino-pharyngeal ones. Clinically this is demonstrated
by adenoids.

10. Peculiarities of the structure of
upper respiratory passages:
 Larynx:
 short, wide, funnel like, with gentle mild cartilages, thin
muscles;
 localized high;
 rima glottis is narrow, vocal cords are short, due to this the
children have loud voice;
 mucous membrane is thin, gentle, rich of vessels, submucous
layer is hydrophilic. This promotes quick development of
swelling and development of “wrong croup";
 in submucous membrane there is much lymphoid tissue.
 Sex differences in the structure arise beginning with 10 years
of age (in boys the angle of the cartilage becomes acute, the
entrance widens, vocal cords become longer; in girls –
lengthening is not considerable, larynx is shorter and wide).

11. Peculiarities of the structure of
upper respiratory passages:
 Trachea:
 narrow, ellipsoid shape (in newborns) and ring like
(in older children);
 cartilage is narrow, mild;
 mucous membrane is gentle, well vascularized;
 bifurcation of trachea is located higher (at the level of
3rd
dorsal vertebra);
 weakly fixed, lightly displaces;
 the number of mucous glands is not large (dryness as
a result).

12. Peculiarities of the structure of
upper respiratory passages:
 Bronchi:
 the right bronchus is wider. Goes almost vertically, the left
bronchus is narrow and goes out under angle (in newborns
equal angles of going out). Due to this –most of the foreign
bodies enter the right bronchus.
 the system of branching out of bronchi is rough, less muscular
fibers. With age branching out of bronchi becomes finer and
to 7th
year the process is completely finished.
 histological structure of bronchial walls is characterized by the
presence of hyaline cartilage plates, weak muscular layer, poor
elastic fibers (there is no adequate cough);
 mucous membrane is thin, well vascularized, but dry.

13. Peculiarities of the structure of lower respiratory
passages
 The lungs:
 by the 4th
month the number of alveoli becomes more;
 after 4 months continues the process of increasing the sizes at the
account of differentiation of the existing apparatus;
 characteristic rough branching out of the bronchial tree;
 histological structure of a lung is characterized by the presence of
loose connective tissue in interlobular membranes and poor elastic
tissue;
 forming of Kohn pores (interalveolar complexes);
 well developed net of blood vessels and accompanying lymphatic
nodes;
 respiratory function depends on the maturity of corresponding
apparatus.

14. Peculiarities of the chest
 The chest:
 convex, short;
 in newborns has round cross (barrel shaped);
 horizontal going out of ribs from the spine;
 in the first months of life the lungs are larger than the
chest and are pressed into the ribs;
 the chest is in the stage of breathing in;
 breathing musculature is poorly developed.

15. Peculiarities of respiration in
children
 superficial, depth – 8-10p. less than in adults;
 large rate of breathing:
 in newborns – 50-60 - 1 min;
 2 weeks-3 months – 40-45 – 1min;
 3-6 months – 35-40 - 1 min;
 7-12 months- 30-35 – 1 min;
 2-3 years – 25-30 – 1 min;
 4-6 years – 20-25 – 1 min;
 7-12 years – 2—22 – 1 min;
 14-15 years – 18-20 –1 min;
 adults – 16 – 1 min.

16. Peculiarities of respiration in
children
 arrhythmia in children – breathing in is shorter than
breathing out, pauses are different. During sleep –
they are rhythmical ;
 the type of breathing depends on age and sex;
 newborns and 1 year –abdominal type of breathing;
 2 years – 8-9 years – mixed type;
 from 10 years –in boys – abdominal;
 girls – breast.

17.  So, taking into account the above said, it can
be concluded that in children of younger age
there are more “favourable” conditions for the
development of respiratory organs pathology.

18. Methods of examination of children
with respiratory organs pathology
 1.Clinical:
 A). questioning (complaints, anamnesis of the disease,
anamnesis of life);
 B). survey;
 C). palpation;
 D). percussion;
 E). auscultation.
 2. Paraclinical:
 A). Laboratory
 general blood analysis, biochemical blood analysis, analysis of
sputum.

19. Methods of examination of children
with respiratory organs pathology
 B). Instrumental
 rentgenological- rentgenography of the lungs, tomography,
rentgenography of nasal cavity, bronchography, radiological
scanning of the lungs;
 endoscopic (bronchoscopy, laryngoscopy).
 C).Functional
 of the function of external breathing – spirography with
determination of vital capacity of the lungs (VCL), forced
VCL, maximal ventilation of the lungs (MVL), rate of air
flow on breath in and breath out;
 functional methods of examination with the use of
pharmacological probes.

20. Methods of examination of children
with respiratory organs pathology
 D). Microbiological methods: samples from fauces and nose,
examination of bronchial secret, pleural sweat.
 E). Allergological diagnostics: skin (applications,
scarification) probes with allergens. Determination of general
IgE and specific IgE to different allergens.
 F). Oxygenometria: direct (determination of oxygen
saturation of blood) and indirect (dynamics of saturation).

21. Cough
 –– defense act of the organism - discharging from the
respiratory passages nasal mucus, exudates, foreign bodies.
 Relatively narrow lumen of respiratory passages in children of
an early age, poor development of muscular membrane of
bronchi promote incompleteness of cough pushes.
 According to rhythm cough can be divided into:
 cough as separate coughing pushes (weak cough): in
neuroses, sinusitis, in the early stages of tuberculosis);
 periodical cough – in patients with pneumonia, chronic
bronchitis. A variation is cough attack, which is the main
symptom of whooping cough.
 Permanent cough – characteristic of patients with pharyngitis,
acute bronchitis.

22. Cough
 If cough is not accompanied with discharge of
sputum, it is called dry, and with sputum
discharge – moist cough.
 according to timbre there are such kinds of
cough:
 barking – in laryngitis;
 loud (as in the tube) – in tracheitis.

23. Sputum
 pathological discharges from respiratory passages. The
amount of sputum always is different:
 little – in bronchial asthma, acute bronchitis, interstitial
pneumonia;
 much – in bronchoectasis, abscessing pneumonia.
 According to character of pathological process sputum can be:
 mucous (colorless, transparent, thick),
 mico-purulent (thick, turbid, contains mucus and pus),
 purulent (in severe purulent bronchitis, abscesses),
 bloody (bleeding in upper respiratory passages, tuberculosis,
high blood pressure in lesser blood circulation circuit).

24. In microscopy in sputum can be:
 neutrophils – fresh purulent process;
 eosinophils – bronchial asthma, bronchitis;
 alveolar cells – fresh inflammatory process;
 in bronchial asthma – spirals of Kurshman,
crystals of Sharko-Leiden.

25. Pains in the chest
 arise in diseases of respiratory system as well
as during the diseases of all other organs in
the chest cavity. Pains in the chest may cause
forced position (in pleuropneumonia,
pleuritis).
 Generally the pains are acute, intensive,
increase in deep breathing, during cough,
moving the arms.

26. Change of the voice in a child
indicates on the disease of mucous membrane of
larynx with lesion of the vocal cords. Under acute
respiratory infections (more often in paragrippe)
develops edema of mucous membrane beneath the
vocal cords- laryngitis, clinically demonstrated by
rough barking cough and harsh voice. In diphtheria of
larynx, when croupous inflammation of vocal cords
develops with formation of a film, the voice is lost
(aphonia). Nasal shade of the voice takes place in
chronic rhinitis and adenoids, retropharyngeal
abscesses, tumors of tonsils. Harsh low voice is
characteristic of mixedema.

27. Change of respiration rate
 Slowing of respiration rate (bradypnea)- is met
rarely. The main reason – hindered function
of respiratory center (severe intoxication, renal
insufficiency, hepatic insufficiency).
 Increase of respiration rate (tachypnea) is
observed under diseases of respiratory and
cardiovascular systems, anemias,
inflammations, pains.

28. Dyspnea Dyspnea is acceleration and hardening of respiration.
Objective symptoms of dyspnea are change of rhythm,
respiration rate and participation of additional respiratory
muscles.
 Differentiation:
 - inspiratory dyspnea – hardened loud breathing in (in
stenosis of the larynx, foreign bodies in trachea, true croup);
 - expiratory dyspnea – hardened prolonged breathing out
with participation of abdominal muscles. It can take place in
narrowing the lumen of bronchi, bronchioles at the account of
edema or their spasm. Is characteristic of obstructive
bronchitis, bronchial asthma;
 mixed – hardened breathing in and breathing out. It can take
place in disturbed pulmonary tissue, pleura, diseases of the
heart, ascites, meteorism.

29. Change in the type of respiration
 Change of thoracic type of breathing for
abdominal one in girls appears in traumas of
the ribs, myositis, fibrinous pleuritis.
 Change of abdominal type of breathing for
thoracic one in boys is a witness of peritonitis,
lesion of diaphragm, ascites, meteorism.

30. The shape of the chest
 In healthy children of an older age the chest is cylinder-shaped.
 In emphysema of the lungs, bronchial asthma, obstructive
bronchitis- the chest is short and wide - barrel-shaped. Such
shape of the chest is physiological in newborns: anterior-
posterior size is actually equal to transversal, horizontal
branching of the ribs.
 Intercostal spaces in healthy children are the same. Widening,
falling out are characteristic of exudative pleuritis, hydro- and
pneumothorax.
 Narrowing and extension – for chronic broncho-pulmonary
processes.
 In healthy children the chest is symmetrical. In pathology the
symmetry is violated with signs of retraction (chronic fibrinous
process in the lungs- exudative pleuritis, pneunothorax).

31. Pathological symptoms in palpation
 Increasing of vocal fremitus- during pathological
processes in pulmonary tissue, accompanied by its
consolidation (in pneumonias).
 Weakening of vocal fremitus - in pleuritis,
pneumothorax, atelectasis, pleural tumors.
 Can also depend on factors not connected with
pathological processes (obesity, edemas, sharp
physical weakness).

32. Changes in percussion sound
 Loss of resonance or dull sound instead of clear one
is observed in:
 decrease of the amount of air in pulmonary tissue
(inflammation, tuberculosis, atelectasis);
 formation in the lungs another airless tissue (tumor,
abscess);
 filling up the pleural cavity with fluid (pleuritis).
 This symptom can also be present in pathology of
trachea-bronchial lymph nodes, cardiovascular
system pathology, thymomegaly, tumors of
mediastinum.

33. Changes in percussion sound
 Thympanic sound appears in:
 formation in the lungs a cavity, full of air
(cavern, cyst, pneumothorax);
 decreasing of elasticity of pulmonary tissue
(emphysema). Besides, in high location of
diaphragm (meteorism).
 Boxing sound - arises when pulmonary tissue
elasticity is sharply decreased (BA,
emphysema).

34. Physical changes (auscultation
symptoms)
 Normally above the pulmonary areas is heard
vesicular respiration (we hear breathing in and
1/3 of breathing out) - sound “f”.
 Above the trachea, larynx, area of location of
large bronchi in healthy children we hear
bronchial respiration - sound “h”.

35. Physical changes (auscultation
symptoms)
 Vesicular breathing, in which breathing in is shortened, and
breathing out is almost unnoticed, is called weakened
breathing. Can be observed physiologically:
 in newborns and 6 months;
 in obesity;
 well developed muscular tissue:
 pathologically:
 in tracheal or bronchial occlusion;
 initial stages of pneumonia;
 under limited respiratory movements;
 in exudative pleuritis, hydrothorax;

36. Physical changes (auscultation
symptoms)
 harsh breathing - such breathing in which
respiratory murmurs are sharply expressed and
equally well is heard breathing in and
breathing out.
 most frequently is present in bronchitis.

37. Physical changes (auscultation
symptoms)
 If bronchial breathing is determined above the
pulmonary areas, it is considered to be
pathology (in considerable, wide spread
consolidation of pulmonary tissue -
polysegmentary, croupous pneumonia,
tuberculosis, atelectasis).

38. Rales
 are additional respiratory murmurs, which arise in
trachea, bronchi, pulmonary cavities due to motion
and vibration of exudate. Differentiation:
 dry and moist rales.
 Dry rales: whistling - obstructive bronchitis;
buzzing - acute simple bronchitis;
in bronchial asthma - different rales.
 Moist rales: fine-, medium-, large-, bubbling rales.

39. Auscultation changes in bronchitis
and pneumonias:
 in bronchitis rales are heard - along the whole
length of the lungs;
 in pneumonia - localized;
 in bronchitis- changing in localization;
 in pneumonia- persistent;
 in bronchitis-not loud;
 in pneumonia - loud (due to infiltration and
consolidation of the lungs tissue).

40. Peculiarities of crepitation :
 is heard at the end of breathing in;
 does not change during cough;
 is scattered in type of localization;
 has a uniform caliber of murmurs.
Crepitation - characteristic sign of
pneumopathias,croupous pneumonia.

41. Pleural murmur
 Additional respiratory murmur, which arises under
pleural pathology (friction of visceral and parietal
layers of pleura). Differentiation of pleural murmur
and crepitation is done according to the following
criteria:
 heard both stages of respiration;
 in pressing with phonendoscope the phenomenon
increases;
 heard more superficially;
 while imitating respiration, crepitation is not heard,
but pleural murmur is preserved.