CLINICAL & APPLIED ANATOMY OF THE RESPIRATORY SYSTEM

DR. AJELETI A. O.

RESPIRATORY SYSTEM

STRUCTURAL DIVISION

• The upper respiratory tract

Nose

Pharynx

Larynx.

• The lower respiratory tract Trachea

Lungs: bronchi, bronchioles, alveolar ducts and alveoli

FUNCTIONAL DIVISION

• CONDUCTING Nose

Pharynx

Larynx

Trachea

Bronchi

Terminal bronchioles

• RESPIRATORY Respiratory bronchioles

Alveolar duct & Alveoli.

RESPIRATORY SYSTEM

FUNCTIONS

• Gaseous exchange

• Olfaction (smelling)

• Vocalization(phonation)

• Breathing(pulmonary ventilation)

NOSE

Divisible into

Vestibule

olfactory

respiratory regions

PHARYNX

• Posterior to the mouth and nasal cavity

• Superior to the esophagus and larynx.

• Divided into:

Nasopharynx

Oropharynx

Laryngopharynx.

• Pharynx functions in:

Digestive system

Respiratory system

Important in vocalization.

LARYNX

LARYNX

• Organ of voice, a hollow, tubular structure inferior to pharynx and connected to the top of the trachea

• It forms the lower part of the anterior wall of the pharynx

• Has mucous lining of that cavity; on either side of it lie the great vessels of the neck

• Larynx is formed by a rigid framework of bones, cartilages, muscles and ligaments..

TRACHEA

• It begins at the inferior border of the cricoid cartilage (C6) as a continuation of the larynx

• It is about 12cm in length and nearly 2.5cm in diameter.

• It ends by bifurcating into the right and left main stem bronchi at the level of the sternal angle of Louis (T4/5)

• It has 15–20 U-shaped incomplete hyaline cartilaginous rings that open posteriorly toward the esophagus and prevent the trachea from collapsing.

LUNGS

• Essential organs of respiration

• Consists of Right & Left lungs

• Attached to the heart and trachea by their roots and the pulmonary ligaments.

• Each lung is conical in shape, blunt apex which reaches above the sternal end of the 1st rib, a concave base overlying the diaphragm

• Consists of lobes

Right lung - 3 lobes

Left lung – 2 lobes

BRONCHIAL TREE

• It’s a function of a

lower respiratory tract

• They are branched

tubes from the trachea -

alveoli

Trachea

Lungs: bronchi,

bronchioles,

alveolar ducts and

alveoli

ALVEOLI

• Alveoli are tiny air sacs in the lungs where gas exchange takes place.

• Alveoli are rich with capillaries.

• Here the red blood cells absorb oxygen from the air

MECHANISM AND MOVEMENTS DURING QUIET INSPIRATION

• Air breaths in[inspiration}

• Diaphragm contracts and moves downward

• Increase intra-abdominal pressure, increase thoracic cavity vertical diameter

• Sternum moves forward and outward

• The movement likened to a tap-handle or pump-handle movement.

• The ribs movement increase the transverse diameter of the thoracic cavity.

• The upwards and outward movement of the rib cage increase the antero-posterior diameter of the thoracic cavity.

• The intra-thoracic pressure reduces and air can diffuse into the lungs.

ANOMALIES & DISEASES OF RESPIRATORY SYSTEM

• AGENESIS OF LUNGS

• TRACHEO-OESOPHAGEAL FISTULA

• BRONCHIAL ASTHMA

• CYSTIC FIBROSIS

• INFANT RESPIRATORY DISTREESS

• EMPHYSEMA

• PLEURAL EFFUSION

• BRONCHOGENIC CARCINOMA

AGENESIS OF LUNGS

• Extremely rare congenital anomaly

• Failure of primitive lung bud development

• Associated with other developmental defects.

• Classified into: bilateral and unilateral

• Bilateral agenesis is lethal

• Unilateral pulmonary agenesis mortality rate > 50%.

TRACHEO-OESOPHAGEAL FISTULA

BRONCHIAL ASTHMA

• Spasm of the smooth muscle in the wall of the bronchioles as a result of inflammation from allergic reactions.

• Classification base on frequency and severity of the signs

mild intermittent: about two days a week and two nights a month

mild persistent: > two times a week, not more than once in a day

moderate persistent: once a day and more than one night a week

Severe persistent: throughout the day on most days and frequently at night.

• Signs and symptoms:

Wheezing and shortness of breath.

Lungs becomes distended

Thoracic cage is enlarged forming the so-called barrel chest.

Increased mucus production

Edema of bronchial walls.

BRONCHIAL ASTHMA

CYSTIC FIBROSIS

• Congenital metabolic disorder in which the secretions of exocrine glands are abnormal in the lungs

• Na+ and water move out of airways, leaving their other secretions sticky.

• Over time the mucus builds up in the airways of the patient and makes it hard to breathe

• Infection from the trapped germs hence formation of cysts and fibrotic tissue

• Signs and symptoms:

Respiratory: wheezing or trouble breathing,

frequent lung infections.

Non- respiratory: trouble with bowel movements infertility(in men)

trouble gaining weight.

CYSTIC FIBROSIS

LUNG DISEASES AFFECTING ALVEOLI:

INFANT RESPIRATORY DISTREESS

• Lung disease due to incomplete differentiation of the type II alveolar cells

• Resultant deficit in the surfactant production

• Occurs in babies born before the 28th week of gestation

• Incompatible with life.

• Signs and symptoms:

difficulty in breathing

inability to expand the lungs.

EMPHYSEMA

• Lung condition that causes shortness of breath due to the damage of the air sacs

• Over time the inner walls of the air sacs weaken and rupture thereby creating larger air spaces rather than small, numerous ones reducing the surface area of the lungs

• It is also associated with chronic bronchitis

• Smoking is the leading cause of emphysema.

• Signs and symptoms: shortness of breath

EMPHYSEMA

DISEASES OF PLEURAL CAVITY

• Diseases of pleural cavity, pleura may be filled with

• Air- pneumothorax

• Fluid- pleural effusion

• Blood- haemothorax

• Pus- empyaema

• General rule is to drain what should not be in the pleural cavity- chest tube insertion

PLEURAL EFFUSION

• Pleural effusion is an unusual amount of fluid in the lungs. The lung is normally invested in a pleural cavity that contains pleural fluid. However, there could be accumulation of excess pleural fluid called pleural effusion

• Causes: leakage from other organs, autoimmune conditions, pulmonary embolism, cancer, infections etc.

• Signs and symptoms: shortness of breath, chest pain, fever, cough.

• Diagnosis: computed tomography, chest x-ray, ultrasound.

• Classification: transudative & exudative

• Treatment: tube thoracostomy, pleural drain, plerual decortication, pleurodesis.

BRONCHOGENIC

CARCINOMA

• It begins as hyperplasia of the

respiratory epithelium that lines the

bronchi.

• Classification:

adenocarcinoma(distal airway and

alveoli)

squamous cells carcinoma(large

bronchi)

small cell carcinoma(larger bronchi)

• It has 35% incidence and is associated

with smoking.

• Treatment: chemotherapy, radiation

therapy, lung transplant.

ASPIRATION OF FOREIGN

BODIES

• When a strange object is aspirated in a child

for example, it most likely enters the right

main bronchus due to its width and

(less)obliquity.