Case 2- Asthma Flashcards
Community asthma treatment
- SABA
- ICS
- LTRA
- LABA
- MART regime (low dose ICS and a LABA) + SABA + LTRA
- Increase ICS (or change to moderate ICS and LABA)
- Increase ICS, theophylline, LAMA
- Specialist
NB- if well controlled (eg. not using blue inhaler for a year), you can trial step down of treatment eg. aim for a reduction of 25-50% in the dose of inhaled corticosteroids
Additional asthma treatment
Flu jab/ pneumococcal vaccine
Yearly asthma review
Advise exercise and avoid smoking
Treatment of a primary non-tension pneumothorax
Asymptomatic and less than 2cm rim of air- conservative treatment. Follow up in 2 weeks (CXR)
Symptomatic and more than 2cm rim of air- needle aspiration
If aspiration fails twice- chest drain
Unstable patients/ bilateral- chest drain
Life long scuba diving ban
Treatment of a tension pneumothorax
Needle aspiration and chest drain- CXR to check for correct placement
Life long scuba diving ban
Typical asthma Sx
Persistent dry cough that worsens at night, with exercise, cold or exposure to irritants, exploratory wheeze, dyspnoea, chronic allergic rhinitis with nasal congestion
Asthma differentials
CF, bronchiectasis, COPD, PE, pneumothorax
Investigations for suspected asthma
Observations and physical exam
Fractional expired NO- increased (check this.. )
Spirometry with bronchodilator reversibility testing- value of at least 200ml and 12% increase (no bronchodilators when assessing baseline)
PEFR- diary for 2-4 weeks (diurnal variation- 20% variation)
FBC- neutrophilia and eosinophilia
CXR- exclude another pathology
NB- don’t routinely use spirometry on its own to diagnose asthma as patients won’t show any abnormality when asymptomatic (if spirometry is normal, you cant exclude asthma, you have to do further tests ie. FeNO)
Blood gas
Consider in any acute respiratory situation
Gives good insight into patients respiratory function- ABG favoured over VBG
In asthma- if sats below 92%
Forced vital capacity (FVC)
Total volume expelled without time limit from maximal inspiration to forced maximal expiration (calculated as a % of predicted value)
Restrictive- less than 80%
Obstructive- normal
Total lung capacity (TLC)
Low in restrictive disorders
High in obstructive disorders
Graph interpretation (time vs volume expired)
Normal- rapid increase in volume of air expired and then curve forms a plateau
Obstructive- prolonged increase (air cannot be expired as quickly due to airway resistance) but ends at same point as the FVC is normal
Restrictive- rapid increase as normal, but curve forms a plateau much sooner (total air volume in lungs is much smaller)
Graph interpretation (volume expired vs exploratory flow rate)
Normal- rapid increase in flow rate, then gradual decrease until the end of expiration
Obstructive- decreased peak exploratory flow rate with steeper reduction in flow rate after it peaks causing a characteristic dip in curve (collapse of small airways)
Restrictive- curve is normal in shape but smaller due to proportionally reduced flow rates (volume in the lungs is reduced)
Long term oxygen therapy
pO2 of <7.3 or pO2 7.3-8.0 and one of the following;
-polycythaemia
-peripheral oedema
-pulmonary HTN
Raised TLCO
Asthma
Pulmonary haemorrhage
Left to right cardiac shunt
Polycythaemia
Hyperkinetic state
Male gender
Exercise
Reduced TLCO
Pulmonary fibrosis
Pneumonia
Pulmonary embolism
Pulmonary oedema
Emphysema
Anaemia
Low cardiac output
KCO
Corrected TLCO for lung volume
Increases with age
Increased KCO with normal or reduced TLCO
Pneumonectomy
Scoliosis or kyphosis
Neuromuscular weakness
Ankylosis got spondylitis
Moderate acute asthma features
PEFR 50-75%
Normal speech
RR<25
Pulse<110
Severe acute asthma features
PEFR 30-50%
Can’t complete sentences
RR>25
Pulse>110
Acute life threatening asthma
PEFR <33%
Oxygen sats<92%
Silent chest, cyanosis, feeble resp. Effort
Bradycardia, dysrhythmia, hypotension
Exhaustion (normal pCO2- bad sign), confusion, hypotension
Acute near fatal asthma
Raised pCO2 and or requiring mechanical ventilation with raised inflation pressures
Acute asthma management
Admission (ie. To ward overnight)- life threatening features or pregnancy/night time attack, previous near fatal attack, already on oral steroids
Only do ABG if sats below 92%
O- oxygen (94-98%)
S- salbutamol via oxygen driven nebuliser
H- prednisolone (PO) 40mg (for 5 days if in community)
I- ipratropium bromide (severe or life threatening)
T- IV theophylline
M- IV MgSo4
E- escalation to ITU/HDU
NB- bottom 3 need senior input
NB- steroid is oral, not IV (unless vomiting/cannot swallow)
Criteria for discharge following an acute asthma attack
Been stable on discharge medications for 12-24 hours (no oxygen or nebulisers)
Inhaler technique checked and recorded
PEFR>75%
Acute bronchitis features
Cough (may or may not be productive)
Sore throat
Rhinorrhoea
Wheeze
NB- normally a normal chest exam
Management of acute bronchitis
Analgesia
Good fluid intake
Antibiotics if- systemically unwell, pre existing co morbidities, CRP 20-100 (delayed), CRP 100 (immediate)) - doxycycline (alternative is amoxicillin for children and pregnant women)
Occupational asthma
Symptoms are better at weekends/ when away from work
Serial measurements of peak expiratory flow at work and away from work
Treatment of a secondary non tension pneumothorax
All patients admitted for at least 24 hours
If patient 50+ and rim of air is >2cm or patient is SOB- chest drain
If between 1-2cm, aspiration (fails- chest drain)
If less than 1cm- give oxygen and admit for 24 hours
Life long scuba diving ban
NB- if re-occurs: VATS procedure
Obstructive lung disease
FEV1- reduced
FVC- normal
FEV1/FVC (FEV1%)- reduced
Asthma, COPD, bronchiectasis
Restrictive lung disease
FEV1- reduced
FVC- reduced
FEV1%- normal or increased
Pulmonary fibrosis, asbestosis, sarcoidosis, ARDS, ankylosing spondylitis, neuromuscular disorders, severe obesity
ABG in acute asthma exacerbation
Respiratory alkalosis then respiratory acidosis- CO2 is rising
Follow up after acute asthma discharge
GP notified within 24 hours of discharge- follow up within 2 days
LABA example
Salmeterol
SAMA example
Ipratropium
LAMA example
Tiotropium
Chest drain safety triangle
The triangle is located in the mid axillary line of the 5th intercostal space. It is bordered by:
Anterior edge latissimus dorsi, the lateral border of pectoralis major, a line superior to the horizontal level of the nipple, and the apex below the axilla.
NSAID’s and asthma
You shouldn’t prescribe NSAID’s in asthmatic patients- can precipitate bronchospasm
Lung lobes
3 on RHS (upper lobe is very large- consolidation may look like middle lobe, but you can work it out whether its the horizontal or oblique fissure)
2 on LHS
