Respiratory System Lecture 1 Overview 12/19/20151

Anatomy The respiratory system consists of upper and lower respiratory tracts Upper respiratory tract: filter and warm air Lower respiratory tract: gas exchange The upper and lower respiratory tract work together to facilitate ventilation Ventilation : is movement of air in and out of the airways 12/19/20152

Upper respiratory tract The upper respiratory tract consists of : Nose, sinuses, nasal passages, pharynx, tonsils and adenoids, larynx, and trachea Nose: act as a passage for air ways. The nose is lined with highly ciliated mucus membrane called the nasal mucosa Nasal mucosa secrete mucous The nose filter and humidify air 12/19/20153

Cont--Upper respiratory tract Paranasal sinus : four pairs of bony cavities that are lined with nasal mucosa Main function for sinus is to serve as a resonating chamber for speech Sinus is a common site for infection: sinusitis Turbinate bone( conchae): bone with curve increases the mucos membrane surface of nasal pasage 12/19/20154

Cont--Upper respiratory tract Pharynx: connect nasal and oral cavities to the larynx Tonsils : lymphoid tissue that has a role in immunity The adenoid(pharyngeal tonsils): located in the roof of nasopharynx Larynx: the voice organ. Connect the pharynx and trachea. Epiglottis : cover the opening of larynx during swallowing Trachea : passage between larynx and bronchi 12/19/20155

Lower respiratory tract Lungs : left lung has 2 lobes. The right lung has 3 lobes Pleura : the lungs and the wall of thorax are lined with serous membrane called the pleura. The visceral pleura cover the lung and the parietal pleura line the thorax. Mediastinum: the middle of the chest 12/19/20156

Pulmonary circulation: blood pumped by the right ventricle. The pulmonary artery pressure is systole/ 5-15 diastole mmHg. Ventilation-perfusion: ventilation is the flow of gas while perfusion is the filling of pulmonary capilary with blood. Under normal condition 4L of air enter respiratory tract while 5 L blood go through pulmonary circulation : ventilation perfusion match 12/19/20157

The normal ventilation/perfusion ratio is 4/5 which is 0.8 Low ventilation perfusion ratio ( shunt) : perfusion exceed ventilation such as in most lung disease High ventilation perfusion ratio ( dead space): no enough blood reach the lung such as pulmonary embolism Silent unite : no ventilation and no perfusion such as pneumothorax 12/19/20158

Assessment of respiratory system Dyspnea: difficult or labored breathing Orthopnea: inability to breath easily except in upright position Cough : dry cough indicate viral infection, cough with sputum especially at morning indicate bronchitis. Sputum production: usually sputum that is thick yellow, green or rust indicate bacterial infection. Sputum: smoking is contraindicated in sever sputum 12/19/20159

Chest pain Wheezing : heared during expiration indicate narrowing of the air way. Clubbing of finger: spoon like nail Hemoptysis : expectoration of blood from respiratory tract indicate infection, cancer or abnormal blood vessles Cyanosis: very late indicator of hypoxia 12/19/201510

Respiratory system diagnostic evaluation Pulmonary function test: usually for patient with chronic respiratory disorder. Non invasive Give many measures that include : tidal volume, forced expiratory volume in 1 second, and vital capacity. Arterial blood gas samples : give PO2, PCO2, HCO3, pH 12/19/201511

Arterial blood gas sample (ABG ) 12/19/201512

Pulse oximetry: non invasive monitor for oxygen saturation. Should be above 95%. Value below 85% indicates that the tissue is not getting enough oxygen sputum culture: to identify microorganisms that cause an infection Sterile procedure Patient is instructed to rinse the mouth, take few deep breath then cough ( not spit) and expectorate into sterile container 12/19/201513

Chest x ray: non invasive. Preferably taken during inhalation Computed tomography ( CT scan): multiple layers in the lung is scanned using narrow beam x ray. Give cross-sectional views for the lung Magnetic reasonance imaging (MRI): Similar to CT scan except that magnetic filed and radiofrequency is used. 12/19/201514

Bronchoscopy : dierct visualization of the respiratory tract Used to diagnose and treat respiratory disease. also can be used to obtain specimen Can be sued to remove secretion or foreign bodies Invasive ( need informed consent). Patient should be NPO 6 hrs before the procedure Patient should remove denture 12/19/201515

Cont---Bronchoscopy: Minor sedation is given ( midazolam) After the procedure NPO till patient resume cough reflex 12/19/201516

Bronchoscopy 12/19/201517

Thoracentesis: aspiration of pleural fluid for diagnostic or therapeutic purpose. Local anesthetic agent is needed Needle is inserted in the pleural space while patient is concious to aspirate either excess pleural fluid as in pleural effusion or blood Usually pain is minimal 12/19/201518

Position for Thoracentesis 12/19/201519

Thoracentesis 12/19/201520

Pleural biopsy: excision of small amount of the pleura 12/19/201521