RESPIRATORY RESPIRATORY SYSTEMSYSTEM

Anatomy• Upper respiratory tract

– Nasal cavity– Paranasal sinuses – Nasopharynx

• Lower respiratory tract– Larynx– Trachea– Bronchial tree– Respiratory part

Airways wall

• Epithelium of the respiratory tract

• Lamina propria

• Submucosa

Epithelium of the RT • pseudostratified columnar with the cilia

– columnar ciliated cells– goblet (mucous) cells– brush cells (microvilli)– Kultchitski cells (DNES)– secretory cells (granulated) – basal cells

• stratified sqamous epithelium

Nasus et cavitas nasi

• function

• cavitas nasi mucosa :

- vestibulum lumen nasi

• regio respiratoria et olfactoria

Sinus paranasalessinus maxillaris (15 cm3) sinus frontalis (8 cm3)sinus sphenoidalis (6 cm3) cellulae etmoidales (ant. et post.)

• the development• epithelium• function

Nasopharynx

= cranial part of the pharynx

• epithelium of the respiratory tract

• mouth of the tubae auditivae in a level of the meatus nasi inferior

• tonsilla pharyngea - Waldeyer´s circle

Larynx

• cartilage

• epiglottis– lingual surface– laryngeal surface

• vocal cords– true– false

Larynx - cartilages:

• cartilago thyroidea • cartilago cricoidea • cartilago epiglottica

• cartilago arytenoidea

• cartilago corniculata, cuneiformis et triticea

Cavitas laryngis• Aditus• Vestibulum

- plica vestibularis - lig.vestibularia - rima vestibuli, ventriculus

• Glottis - plica vocalis, rima glottidis

• Cavitas infraglottica

• lamina propria• submucosa laryngis

D1 - epiglottis (HE)

D2 - larynx (HE)

Trachea• pars cervicalis + thoracica• bifurcatio tracheae (Th4)

• epithelium of the respiratory tract • submucosa - glandulae tracheales

• cartilagines tracheales • ligamenta anularia• paries membranaceus (tracheal muscles, ligaments)

D3 - trachea (HE)

Bronchial tree• Primary bronchi (bronchus pricipalis dx. et sin.)

• Secondary bronchi (bb. lobares bb. segmentales)

• Terminal bronchioles

• Respiratory bronchioles

• Alveolar corridors (ductus sacculi)

• Alveoli

Bronchi

• cartilage - here and there

• smooth muscles - spiral

• epithelium - pseudostratified, ciliated

• lamina propria - seromucinous glands, elastic fibres

• lymphocytes, lymphatic follicles

D4 Intrapulmonary bronchus (HE)

Bronchioles

• epithelium - gradually simple cuboidal - Clara cells

• elastic fibres, smooth muscles

• no cartilage, no glands neither lymphatic follicles

The lung

• Respiratory bronchi

• Alveolar corridors

• Alveoli

• Pleura

Respiratory bronchioles

• simple, cuboidal, ciliated epithelium

• into alveoli - squamous epithelium

• bronchioles gradually transform into the alveolar corridors

Alveoli

• 200 μm large, many-sided, thin wall

• alveolar epithelium

• alveolar septum

Alveolar epithelium• Membranous pneumocytes (type I)

• 97%; desmosomes, zonulae occludentes• squamous, thin - 25 nm• organelles around the nucleus,

pinocytal pouches

• Granular pneumocytes (type II)• ovoid shape, microvilli• lamellar bodies (1,5 μm) - surfactant • proliferation and differentiation (lining renewal)

Alveolar septum

• fibroblasts (collagen type I, III)

• endothelial capillary cells• pericytes • dust cells, lymphocytes• alveolar cells

• reticular and elastic fibres• inter-alveolar pores (10μm)

D5 The lungs (HE)

Alveolar-capillary barrier

0,1- 0,5μm

• alveolar cells (type I) cytoplasm

• basal membranes

• endothelial (capillary) cells

• respiratory surface = 140 m2

Surfactant

• reduces tension on the surface of alveoli

• resists the collapse of the alveoli in expirium

• water hypophase & lipid epiphase

• absorption & renovation in granular pneumocytes

• passage in respiratory tract within the bronchoalveolar fluid

Defence mechanism

• Nose airways - mucous, vibrissae

• Respiratory ciliated epithelium

• Alveolar macrophages

• T a B lymphocytes

Pleura

• serose membrane - mezothelium

• parietal and visceral sheet

• cupula pleurae

• recessus pleurales (costodiaphragmaticus, costo-, phrenico- a vertebromediastinalis)

• pleural cavity - liquosus pleurae

Respiratory system

- the development

The development of the RT• begins in week 4• day 24-26 - laryngotracheal groove =>

laryngnotracheal diverticulum => lung bud bronchial buds...

• tracheo-oesophageal septum => ventral (laryngotracheal tube) dorsal (oropharynx, eosophagus) - parts of the foregut

• tracheoesophageal fistula

The development of the larynx

• epitheliumepithelium - pseudostratified, columnar, ciliated• origin of the cartilages and muscles cartilages and muscles

• aditus laryngisaditus laryngis -

adhesion (month 1), recanalisation• ventriculus laryngisventriculus laryngis

• eminentia hypobranchialis - epiglottisepiglottis

The development of the trachea

• endodermal lining => epithelium and glands

• splanchnic mesoderm => cartilages, connective tissue and muscles of the trachea

The development of the bronchi and the lungs

• lung bud => bronchial buds

• week 5 - primary bronchi => lobar bronchi

• week 7 - segmental bronchi + mesenchym => bronchopulmonal segment

• the end of the week 24 - „level 17“; respiratory bronchiole

• the origin of the visceral, parietal pleura

The maturation of the lungs

• pseudoglandular phase (week 5-17)• canalicular phase (week16-25)• terminal pouches phase (week 24 ad partus)• alveolar phase (late fetal period, childhood)

• adequate space of the chest• fetal breathing movements• adequate volume of the amnion fluid

Adaptive changes to the autonomic breathing

• sufficient amount of the surfactant

• conversion of the function of the lungs (secretory fce - respiratory fce)

• parallel lungs and body circulation

• fluid removal of the lungs: in a course of the delivery lungs capillaries and vessels, lymphatic vessels

D6 Fetal lungs (HE)