asthma

Question 1

Difference between bts and nice guideline on asthma management?

Answer 1

in the 3rd step: Leukrotiene receptor antagonist (BTS) e.g. montelukast is used instead of LABA (nice)

Question 2

BTS guideline with asthma management

Answer 2

BTS/Sign Guidelines on Diagnosis

• High probability of asthma clinically: Try treatment
• Intermediate probability of asthma: Perform spirometry with reversibility testing
• Low probability of asthma: Consider referral and investigating for other causes

Question 3

Nice guideline for asthma diagnosis

Answer 3

ICE recommend assessment and testing at a “diagnostic hub” to establish a diagnosis. They specifically advise not to make a diagnosis clinically and require testing:

First-line investigations:

• Fractional exhaled nitric oxide
• Spirometry with bronchodilator reversibility

If there is diagnostic uncertainty after first line investigations these can be followed up with further testing:

• Peak flow variability measured by keeping a diary of peak flow measurements several times per day for 2 to 4 weeks
• Direct bronchial challenge test with histamine or methacholine

Question 4

Dyspnoea scale

Answer 4

• Grade 1 – Breathless on strenuous exercise
• Grade 2 – Breathless on walking up hill
• Grade 3 – Breathless that slows walking on the flat
• Grade 4 – Stop to catch their breath after walking 100 meters on the flat
• Grade 5 – Unable to leave the house due to breathlessness

Question 5

Diagnosis of COPD

Answer 5

Clinical presentation + spirometry

• FEV1 <80%
• FEV1/FCV <70%

The overall lung capacity is measured by forced vital capacity (FVC) and their ability to quickly blow air out is measured by the forced expiratory volume in 1 second (FEV1).

Question 6

The severity of the airflow obstruction in COPD can be graded using the FEV1:

Answer 6

Question 7

Long term managment of COPD

Answer 7

1. SABA
2. if no asthmatic features: give combined LABA + LAMA

In more severe cases additional options are:

• Nebulisers (salbutamol and/or ipratropium)
• Oral theophylline
• Oral mucolytic therapy to break down sputum (e.g. carbocisteine)
• Long term prophylactic antibiotics (e.g. azithromycin)
• Long term oxygen therapy - SEVERE COPD where they get chronic hypoxia, polycythaemia, cyanosis

Question 8

ABG

Answer 8

• Raised Co2 makes the blood pH more acidotic by breaking down carbonic acid
• Raised bicarbonate means: they chronically retain CO2 and their kidneys have responded by producing more bicarbonate to balance the acidic CO2
• Low po2 indicates respiratory failure/hypoxia

Question 9

In acute exacerbation of COPD, there are x levels of CO2

Answer 9

Rising levels of co2 and the kidneys cant keep up with it.

This can lead to type 2 respiratory failure: High CO2, low oxygen

Question 10

Target 02 saturations in COPD

Answer 10

• If retaining CO2 aim for oxygen saturations of 88-92% titrated by venturi mask
• If not retaining CO2 and their bicarbonate is normal (meaning they do not normally retain CO2) then give oxygen to aim for oxygen saturations > 94%

Question 11

Treatment of acute exacerbation of COPD

Answer 11