respiratory disorders Flashcards
what is hypoxia
condition characterised by an inadequate level of oxygen reaching body’s tissue
what is hypercapnia
condition characterised by an excessive level of carbon dioxide in the blood stream
what is atelectasis
collapse of closure of a part of whole of the lung, resulting in reduced gas exchange
what is cyanosis
bluish discoloration of the skin and membranes as a result of reduced haemoglobin
what is dyspnoea
sensation of difficult breathing NB symptom for evaluating lung and airway function
what is tachypnoea
rapid breathing characterised by abnormally quick breaths, often a sign of respiratory distress
what is bronchoconstriction
generalised constriction of bronchial smooth muscle narrowing the bronchial lumen creating difficulty breathing
what is sputum
mixture of mucous and saliva coughed up from the respiratory tract
what is wheeze
whistling noise characteristic of air passing through a narrow tube
what is haemoptysis
coughing up blood. possible causes: lung infections, bronchial carcinoma, pulmonary oedema
what is bronchospasm
sudden wave of constriction of the muscles in the walls of the bronchi and bronchioles, narrowing the airway
what are crackles/ rales
sounds heard during breathing that resemble fine crackling or popping noises, indicative of fluid in small airways or alveoli
what does CO2 tigger in ventilation reflex
central (medullary) chemoreceptors
what does O2 trigger in ventilation reflex
peripheral (carotid and aortic) chemoreceptors
what affects hypoxia
- O2 delivery to tissue depends on CaO2 and rate of blood flow
- also result from decrease tissue O2 utilization
what is assessed in hypoximia
low PaO2 and low Hb saturation
what are the different types of hypoxia
- anaemic hypoxia
- stagnant hypoxia
- histotoxic hypoxia
- hypoxic hypoxia
what is anaemic hypoxia
reduced number of red blood cells
what is stagnant hypoxia
reduced blood flow
what is histotoxic hypoxia
reduced oxygen utilisation by cells
what is hypoxic hypoxia
reduced partial pressure of O2 in blood cells
what are different causes of O2 deficiency
- O2 deficiency in inspiratory air
- abnormal ventilation
- abnormal diffusion
- decreased transport capacity
- circulatory failure
- vasoconstriction
- increase O2 affinity of haemoglobin
- abnormal diffusion in tissues
- abnormal O2 utilisation
what is acute respiratory distress syndrome
progressive form of acute, hypoxemic respiratory failure with widespread lung inflammation
what causes acute respiratory distress syndrome
- tissue inflammation
- neutrophils/ immune cells are triggered
- surfactant is reduced/ not produced
- start to get alveoli collapse
- ventilation-perfusion mismatch
what triggers acute respiratory distress syndrome
- sepsis
- pneumonia
- aspiration
- trauma
- near drowning
what signs are acute respiratory distress syndrome
- laboured breathing
- severe SOB
- cyanosis
- rapid heart rate
- confusion/ altered mental state
- tachypnoea
- severe fatigue
what are obstructive disorders
limitation of airflow due to partial or complete obstruction, issues with airflow leaving
what are restrictive disorders
reduced expansion of lung parenchyma accompanied by decreased total lung capacity, struggles air going in
what is COPD
- persistent airflow limitation that is usually progressive
- not fully reversible
- chronic inflammatory response
what is emphysema
- irreversible enlargement of airspace distal to terminal bronchiole
- loss of elastic tissue -> loss of recoil
- loss of alveolar surface area and capillary bed -> hypoxia
how is emphysema caused
breakdown of elastase to elastin is not blocked by protease inhibitors
what is chronic bronchitis
- productive cough for three months in 2 years
- dyspnoea and airway obstruction
- inflammation causing mucosal thickening and mucous hypersecretion increasing resistance
what are the signs and symptoms of obstructive and restrictive disease
- chronic productive cough
- barrel chest
- respiratory acidosis
- tachypnoea
- sever fatigue and exercise intolerance
- weight loss
- severe SOB
- wheezing
- pursed lip exhalation
what causes the signs and symptoms in restrictive and obstructive diseases
- mucous/ inflammation in airway
- collapse of alveoli and airways
- decrease elastic recoil and increased lung compliance
- hypoxia
what is hypoxic pulmonary vasoconstriction
- alveoli ventilation is matched to perfusion in capillaries
- decrease in vents increases Pco2 and decreases Po2
- decreased Po2 constricts arteries
what is cor pulmonale
enlargement of right ventricle due to high blood pressure caused by chronic lung disease
what are the signs of cor pulmonale
- raised JVP
- pedal oedema
- ascites
- hepatic congestion
what are teh consequences of ventilatory acclimation to hypercapnia
CO2 retention -> severe reduction in ventilatory drive when receiving supplemental O3
what is asthma
- reversible chronic inflammation of the airways
- increased airway hyoer-responsiveness
what are the two types of asthma
- extrinsic or allergic stimuli
- intrinsic or non-allergic stimuli
what are the causes or extrinsic asthma
- environmental triggers
- allergic reaction
- childhood onset
- most common
what are the causes or intrinsic asthma
- stimulated by respiratory tract infection
- more severe
- adult onset
what pathophysiology triggers asthma attackes
the release of cytokines, immune and inflammation cells - increasing mucus secretion and contraction
what are the signs and symptoms of asthma
- cough
- wheezing
- chest tightness
- tachypnoea
- severe shortness of breath
- hypoxia
what is fibrosis
abnormal and excessive formation of fibrous scar tissue in the lungs decreasing diffusion so decreasing PaO2
what are the causes of firbosis
- idiopathic pulmonary fibrosis
- secondary
what causes secondary fibrosis
inhalation of environmental or occupational pollutants
what is the pathophysiology of fibrosis
- infection/ stimulus
- endothelial damage
- innate and adaptive immunity and fibroblast activation
- inflammation
- myofibroblast activation
- persistent myofibroblast activation
- fibrosis
what are the signs and symptoms of fibrosis
- dry cough
- tachypnoea
- chest tightness
- sever SOB
- fatigue
what is a pulmonary embolism
sudden blockage of one or more arteries in the lungs by a blood clot
what causes a PE
- DVT
- stasis of blood
- increased blood coagulability
- venous endothelial injury
what is the pathophysiology of a PE
- Virchow’s triad for DVT which moves
- VQ mismatch as lung is not properly perfused
what are the symptoms of a PE
- swollen, tender, warm, redden calf
- chest pain - sharp/ stabbing
- cough and haemoptysis
- tachycardia
- sudden onset of dyspnoea
what is pulmonary oedema
accumulation of excess fluid in interstitium or alveolar spaces resulting in impaired gaseous exchange
what are the two different types of pulmonary oedema
- cardiogenic pulmonary oedema
- noncardiogenic pulmonary oedema
what causes cardiogenic pulmonary oedema
- heart cant pump blood effectively
- increase hydrostatic pressure and exceeds capacity for fluid clearance
- forces fluid into lung tissue
what causes non-cardiogenic pulmonary oedema
- damage or dysfunction of lung tissue or blood vessels
- increased vascular permeability
- forces fluid to lung tissue
- include allergic reaction, trauma, lung infection
what is the effects of pulmonary oedema
- alveolar collapse
- increase surface forces
- decrease pulmonary compliance and decrease gaseous exchange
- results in hypoxemia
what are the signs and symptoms of pulmonary oedema
- wheeze or crackles
- chest pain and tightness
- dyspnoea
- tachypnoea
- fatigue
- cough and blood tinged sputum
what is pleural effusion
fluid in the pleural space from an increase production or decreased reabsorption of fluid
what is exudative pleural effusion
alteration in vascular permeability or fluid reabsorption
what is transudative pleural effusion
effusion from hydrostatic and oncotic imbalance so fluid leaks into pleural space
what are the signs and symptoms of pleural effusion
- dyspnoea
- cough (dry)
- chest pain (pleuritic)
- decreased breath sounds
what is the difference between pulmonary oedema and pleural effusion
fluid accumulate in the lung in oedema and in the pleural space in pleural effusion
what is bronchiectasis
permanent/ abnormal dilation of bronchi and bronchioles and weakening of mucociliary transport mechanism from inflammation
what is the cause of bronchiectasis
damage to airway walls loses structural integrity so mucous can’t be cleared
what is bronchomalacia
excessice and abnormal softening of bronchial cartilage causing weakening and collapse of the airway
symptoms of bronchomalaci
- coughing
- wheeze
- dyspnoea
what is the pathophysiology of bronchomalacia
- forced expiration increases positive pressure
- collapse of non-rigid portion of bronchus
- wheeze and decrease removal of secretion
what is anaphylaxis
systemic hypersensitivity reaction from inflammatory mediators
symptoms of anaphylaxis
- difficulty breathing
- swelling face and throat
- drop in BP
- hives
- GIT distress
what does capnography measure
- real time info of respiratory status
- assesses exhaled CO2
how do ACE inhibitors affect respiration
- ACE-1 is a competitive inhibitor
- prevents degradation of bradykinin and substance P
- accumulation in respiratory tracts stimulates J receptors
- causes a cough
how does opioid overdose affect respiration
- hyperventilation, hypercapnia, respiratory acidosis
- decreased O2 sat and decreased upper airway patency
- hypoxia and hypercapnia
- opioid act on mu receptors which causes respiratory destress
