Breathlessness Flashcards
COPD?
Emphysema + chronic bronchitis
COPD symptoms?
Shortness of breath
Persistent chesty cough
Frequent chest infections
Persistent wheezing
Causes of COPD?
Inflammation, damage and narrowing of lungs
From smoking usually, or harmful fumes and dust
Treatments for COPD
Stop smoking
Inhalers and medicines
Pulmonary rehabilitation
Surgery or transplant
Common COPD comorbidities
Heart disease
Asthma
Diabetes
Lung cancer
Infection
Anaemia
Anxiety
COPD timeline to mortality upon exacerbation
- Exacerbation
- Decreased lung function
- Decreased physical exercise
- Decreased quality of life
- Further exacerbations
- Mortality
How to look at chest X-rays - ABCDE
- Airways - trachea in middle or side?
- Breathing - lungs - abnormal white (stuff) or black (air, pneumothorax)
- Cardio - heart should be more than 50% of chest size, position
- Diaphragm - want to see costophrenic angle, flattened?
- Everything else - other paraphernalia, fractures
White stuff on chest X-ray
Consolidation, opacification
Other things to look for in breathless chest X-ray
Pleural effusion - fluffy looking
Lung tumour - solid looking compared to consolidation
Other investigations for infective exacerbation of COPD?
CXR
Bloods
ECG
sputum
ABG
ABG abnormalities?
pH - acidosis/alkalosis
pCO2 - hypercapnia, respiratory
pP2 - hypoxia
HCO3 - metabolic
Low pH, high CO2
Respiratory acidosis
Low pH, low HCO3
Metabolic acidosis
High pH, low CO2
Respiratory alkalosis
High pH, high HCO3
Metabolic alkalosis
Type 1 respiratory failure
Hypoxia without hypercapnia
PaO2 smaller than 8 kPa
Impaired oxygenation of the blood
Type 2 respiratory failure
Hypoxia with hypercapnia
PaCO2 more than 6.5
O2 less than 8kPa
Impaired excretion of CO2 from the lungs
Examples of type 1 respiratory failure
Pneumonia
Pulmonary oedema, embolism, fibrosis, contusion
ARDS
Aspiration
Lung collapse
Asthma
Pneumothorax
Examples of type 2 respiratory failure
Reduced respiratory drive (drug overdose, head injury)
Upper airway obstruction (oedema, infection, foreign body)
Late severe acute asthma
COPD
Peripheral neuromuscular
Flail chest injury
Exhaustion
Type 2 respiratory failure influenced by concomitant acute renal failure?
Kidneys should reabsorb HCO3 and secrete H+ to compensate in respiratory acidosis
In renal failure, they cannot compensate
Metabolic compensation?
Hypoventilation = increased CO2 = decreased plasma pH = respiratory acidosis
Kidneys secrete H+ and reabsorb HCO3 = increased plasma pH = metabolic compensation
Respiratory compensation
Acute renal failure = less H+ excretion and less HCO3 reabsorption = decreased plasma pH = metabolic acidosis
Lungs hyperventilate = decreased CO2 and increased O2 = increased plasma pH = respiratory compensation
Treatment of COPD
1st line = short acting bronchodilator
Corticosteroid - anti-inflammatory
Ventilation
Antibiotics in infection
Treatment with comorbidities?
Diabetes - be careful of corticosteroids as can induce hyperglycaemia
Depression - link between cortisol and deoression
Oxygen - want lower in COPD
O2 stats
Typically want above 94%, but in COPD want between 88-92% as COPD can lead to hypercapnia (Haldane effect)
Haldane effect
Too high O2 can cause displacement of CO2 from deoxyhaemoglobin so CO2 detaches from deoxyhaemoglobin and remains in blood instead
Pulmonary hypertension in COPD
Hypoxia causes vasoconstriction due to diversion of blood from poorly oxygenated areas of lungs to the more active, oxygenated areas (pulmonary vascular remodelling). This leads to increased resistance and pressure, so pulmonary hypertension
Pulmonary hypertension effect on heart?
Right side of heart to work too hard = hypertrophy = right sided failure = pressure building up in venous system
Reason for oedema (in foot)
Capillary in foot has hydrostatic pressure that pushes fluid out between capillary endothelial cells
Oncotic pressure draws it back in again
Due to pressure building up in venous system, hydrostatic pressure higher than normal so net loss of fluid is even greater so leaves into tissue. Lymphatic capillaries cannot remove all of the fluid so causes oedema.
ABG interpretation
- pH
- Disturbance - metabolic (HCO3J or respiratory (CO2)
- Anion gap? High = lactic acidosis, ketoacidosis, toxins and renal failure. Normal = diarrhoea and renal tubular acidosis
- Compensation
Respiratory compensation
Begins in first hour
Metabolic compensation
Takes several days so evident in chronic respiratory conditions
Why does fluid leave capillaries into tissues and lymphatics?
Due to hydrostatic pressure (driven) being greater than oncotic pressure - pushes fluid through endothelial gaps
What pulls fluid back into capillaries?
Oncotic pressure from proteins in blood
Compare hydrostatic pressure and oncotic pressure from start to end of capillary
Hydrostatic pressure is dominant at start of capillary so more fluid goes out of the start, but hydrostatic pressure falls at end of capillary so oncotic pressure is dominant and draws fluid back in. Very small net loss to lymphatic system.
High anion gap
High = lactic acidosis, ketoacidosis, toxins and renal failure.
