Breathlessness

Question 1

COPD?

Answer 1

Emphysema + chronic bronchitis

Question 2

COPD symptoms?

Answer 2

Shortness of breath
Persistent chesty cough
Frequent chest infections
Persistent wheezing

Question 3

Causes of COPD?

Answer 3

Inflammation, damage and narrowing of lungs
From smoking usually, or harmful fumes and dust

Question 4

Treatments for COPD

Answer 4

Stop smoking
Inhalers and medicines
Pulmonary rehabilitation
Surgery or transplant

Question 5

Common COPD comorbidities

Answer 5

Heart disease
Asthma
Diabetes
Lung cancer
Infection
Anaemia
Anxiety

Question 6

COPD timeline to mortality upon exacerbation

Answer 6

1. Exacerbation
2. Decreased lung function
3. Decreased physical exercise
4. Decreased quality of life
5. Further exacerbations
6. Mortality

Question 7

How to look at chest X-rays - ABCDE

Answer 7

1. Airways - trachea in middle or side?
2. Breathing - lungs - abnormal white (stuff) or black (air, pneumothorax)
3. Cardio - heart should be more than 50% of chest size, position
4. Diaphragm - want to see costophrenic angle, flattened?
5. Everything else - other paraphernalia, fractures

Question 8

White stuff on chest X-ray

Answer 8

Consolidation, opacification

Question 9

Other things to look for in breathless chest X-ray

Answer 9

Pleural effusion - fluffy looking
Lung tumour - solid looking compared to consolidation

Question 10

Other investigations for infective exacerbation of COPD?

Answer 10

CXR
Bloods
ECG
sputum
ABG

Question 11

ABG abnormalities?

Answer 11

pH - acidosis/alkalosis
pCO2 - hypercapnia, respiratory
pP2 - hypoxia
HCO3 - metabolic

Question 12

Low pH, high CO2

Answer 12

Respiratory acidosis

Question 13

Low pH, low HCO3

Answer 13

Metabolic acidosis

Question 14

High pH, low CO2

Answer 14

Respiratory alkalosis

Question 15

High pH, high HCO3

Answer 15

Metabolic alkalosis

Question 16

Type 1 respiratory failure

Answer 16

Hypoxia without hypercapnia
PaO2 smaller than 8 kPa
Impaired oxygenation of the blood

Question 17

Type 2 respiratory failure

Answer 17

Hypoxia with hypercapnia
PaCO2 more than 6.5
O2 less than 8kPa
Impaired excretion of CO2 from the lungs

Question 18

Examples of type 1 respiratory failure

Answer 18

Pneumonia
Pulmonary oedema, embolism, fibrosis, contusion
ARDS
Aspiration
Lung collapse
Asthma
Pneumothorax

Question 19

Examples of type 2 respiratory failure

Answer 19

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

Question 20

Type 2 respiratory failure influenced by concomitant acute renal failure?

Answer 20

Kidneys should reabsorb HCO3 and secrete H+ to compensate in respiratory acidosis
In renal failure, they cannot compensate

Question 21

Metabolic compensation?

Answer 21

Hypoventilation = increased CO2 = decreased plasma pH = respiratory acidosis
Kidneys secrete H+ and reabsorb HCO3 = increased plasma pH = metabolic compensation

Question 22

Respiratory compensation

Answer 22

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

Question 23

Treatment of COPD

Answer 23

1st line = short acting bronchodilator
Corticosteroid - anti-inflammatory
Ventilation
Antibiotics in infection

Question 24

Treatment with comorbidities?

Answer 24

Diabetes - be careful of corticosteroids as can induce hyperglycaemia
Depression - link between cortisol and deoression
Oxygen - want lower in COPD

Question 25

O2 stats

Answer 25

Typically want above 94%, but in COPD want between 88-92% as COPD can lead to hypercapnia (Haldane effect)

Question 26

Haldane effect

Answer 26

Too high O2 can cause displacement of CO2 from deoxyhaemoglobin so CO2 detaches from deoxyhaemoglobin and remains in blood instead

Question 27

Pulmonary hypertension in COPD

Answer 27

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

Question 28

Pulmonary hypertension effect on heart?

Answer 28

Right side of heart to work too hard = hypertrophy = right sided failure = pressure building up in venous system

Question 29

Reason for oedema (in foot)

Answer 29

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.

Question 30

ABG interpretation

Answer 30

1. pH
2. Disturbance - metabolic (HCO3J or respiratory (CO2)
3. Anion gap? High = lactic acidosis, ketoacidosis, toxins and renal failure. Normal = diarrhoea and renal tubular acidosis
4. Compensation

Question 31

Respiratory compensation

Answer 31

Begins in first hour

Question 32

Metabolic compensation

Answer 32

Takes several days so evident in chronic respiratory conditions

Question 33

Why does fluid leave capillaries into tissues and lymphatics?

Answer 33

Due to hydrostatic pressure (driven) being greater than oncotic pressure - pushes fluid through endothelial gaps

Question 34

What pulls fluid back into capillaries?

Answer 34

Oncotic pressure from proteins in blood

Question 35

Compare hydrostatic pressure and oncotic pressure from start to end of capillary

Answer 35

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.

Question 36

High anion gap

Answer 36

High = lactic acidosis, ketoacidosis, toxins and renal failure.