asthma Flashcards
treatment of mind to moderate asthma
- Follow the patient’s asthma action plan if they have one.
- Measure and record the patient’s peak expiratory flow rate (PEFR) before and after treatment if a PEFR meter is available.
- Administer bronchodilators:
a) Use the patient’s metered dose inhaler (MDI) if it is available, or
b) Administer 5 mg of salbutamol nebulised in combination with 0.5 mg of
ipratropium nebulised if the patient’s MDI is unavailable. - Administer an oral steroid:
a) 40 mg of prednisone PO for an adult.
b) See the paediatric drug dose tables for a child.
c) Do not routinely administer an oral steroid to a child aged less than five
years. Consider administering an oral steroid if there is a clear history of asthma and the child has previously been prescribed oral steroids. - Consider the likelihood that transport may not be required if the patient rapidly improves with bronchodilators via an MDI, or following one dose of nebulised bronchodilators.
- Administer further doses of salbutamol as required.
on top of neb, outline the treatment of severe asthma
Administer adrenaline IM if the patient is not improving:
a) Administer 0.5 mg IM for an adult.
b) See the paediatric drug dose tables for a child.
* Gain IV access.
* Adrenaline IM may be repeated every ten minutes if the patient is deteriorating and adrenaline IV is not being administered.
* Begin transport without delay, providing most treatments en route.
* Administer magnesium IV:
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a) Administer 10 mmol (2.47 g) IV over approximately 15 minutes for an adult. b) See the paediatric drug dose tables for a child and administer over
approximately 15 minutes.c) A second dose may be administered if transport time is longer than 30 minutes and the patient is not improving.
* The administration of an oral steroid is not a priority, but should occur if the patient is able to swallow, using the doses described above.
mechanism of magnesium
- Magnesium is the active ingredient in magnesium sulphate.
- Magnesium reduces bronchial smooth muscle contraction resulting in bronchodilation.
asthma non trasporto criteria
Known asthma, and
ū Talking in full sentences, and
ū An SpO2 greater than or equal to 94% when breathing air, and
ū Observed by ambulance personnel for a minimum of 20 minutes following
completion of the last bronchodilator administration, and
ū Observed to mobilise normally, and
ū A PEFR greater than 70% of their normal PEFR (do not use this if the patient
does not normally use a PEFR meter), and
ū Able to see a doctor (preferably their own GP) within two days, and
ū Provided with a prednisone pack (if appropriate), an information sheet and
the information within it is explained to them and to any carers.
If the patient has signs of a chest infection (for example fever or purulent sputum), the patient should be seen by a doctor within 12 hours. This should usually be in primary care (preferably by their own GP) if all of the other non- transport criteria are met.
basic patho of asthma
Asthma is characterised by reversible bronchospasm. It is caused by
an inflammatory state within the lungs resulting in recurrent attacks of breathlessness and wheezing. It is often associated with mucus plugging of airways.
characteristics of mild asthma
Patients with mild to moderate asthma are short of breath but are able to speak in sentences, are usually moving enough air to generate a loud wheeze, do not have significant chest or neck indrawing, have a normal SpO2 and a normal level of consciousness.
charecteritsitcs of severe asthma
Patients with severe asthma are very short of breath, are only able to speak
a few words with each breath, may only be moving enough air to generate a quiet wheeze, usually have significant chest or neck indrawing, may be in the tripod position, usually have an SpO2 of greater than 90% (SpO2 falls very late in the progression of asthma) and may be agitated.
life threat asthma charerctertistics
Patients with immediately life-threatening asthma are extremely short of breath, are usually unable to speak, are moving very little air and may not be moving enough air to create wheeze, usually have marked indrawing but this may not be present if they are exhausted, may have a rapidly falling SpO2 and usually have severe agitation or a falling level of consciousness.
what is PERF
(PEFR) is the maximum flow rate achieved by the patient during forced/rapid expiration and is measured in litres/minute.
why briocodilators are not effective on kids
Children aged less than one year have poorly developed bronchial smooth muscle and fewer beta-2 receptors than adults and for these reasons bronchodilators provide very little benefit.
Differentiating asthma from cardiogenic pulmonary oedema
- Pulmonary oedema may produce a wheeze that sounds like asthma.
- If the patient does not have a history of asthma, the possibility of cardiogenic pulmonary oedema should be considered. Cardiogenic pulmonary oedema is the likely diagnosis when the patient has been supine (for example in bed), and the wheeze is worse bilaterally in the lower zones. The patient is often hypertensive, clammy and peripherally vasoconstricted.
- The patient may have a history of both asthma and pulmonary oedema. In this setting the patient may be able to tell you which condition is causing their shortness of breath.
- Asthma is the likely diagnosis if the onset is associated with a cough and the wheeze is heard evenly through all lung fields. The patient is usually normotensive and not peripherally vasoconstricted.
Differentiating asthma from COPD
It is necessary to distinguish asthma from COPD because the treatments are different.
* Patients with asthma are usually symptom free between attacks.
* Patients with COPD usually have a history of smoking and are not symptom free between attacks.
Dynamic hyperinflation (gas trapping) occurs when
Dynamic hyperinflation (gas trapping) occurs when the amount of gas within the lungs increases in the presence of severe bronchoconstrictionThis occurs because the resistance to gas leaving the lungs during expiration is higher than the resistance to gas entering the lungs during inspiration.
