Acute Asthma/Anaphylaxis Management Flashcards
What is the target SaO2 level for treatment in acute asthma?
SaO2 >94%
Administer 100% O2 via non-rebreather mask to achieve this target.
List some features of a life-threatening asthma attack.
- Unable to speak
- Confused
- Cyanotic
- Poor respiratory effort
- Silent chest
- SaO2 < 92% / PaO2 < 8 kPa
- PEFR <33% predicted
- HoTN
- Bradyarrhythmias
History of severe attacks may warrant admission even without life-threatening features.
What are the signs of asthma exacerbation in a respiratory exam?
- Shortness of breath (SOB)
- Wheeze
- Tachypnoea
- Hypoxia
These signs are indicative of asthma during the focused examination.
Which condition can present with urticarial rash and angioedema as differential diagnoses in acute asthma?
Anaphylaxis
Allergens such as IV antibiotics may be involved.
What does a normal or raised PaCO2 indicate in an ABG for acute asthma?
Warrants transfer to HDU or ICU
This is a critical indicator of respiratory failure.
What is the treatment regimen for acute asthma?
What is the initial dose of oral prednisolone in the treatment of acute asthma?
40 mg OD
IV hydrocortisone 100 mg QDS may be given if the patient cannot tolerate tablets.
What adjunct treatments may be used in life-threatening asthma?
- IV magnesium sulphate
- IV aminophylline
- IV salbutamol
- NIV (BiPAP)
- Intubation
These treatments are considered when immediate action is required.
What criteria must be met for discharge after an acute asthma attack?
- Stable on discharge meds for 12-24 hours
- Inhaler technique checked and recorded
- Emergency action plan written and agreed upon
- PEF >75% of best or predicted
These criteria ensure the patient is ready to manage their condition at home.
Fill in the blank: A PEFR <33% predicted indicates _______.
life-threatening asthma
This is a key feature indicating severity.
What investigations should be conducted in acute asthma?
- ABG
- PEFR
- Sputum culture (if suspected infection)
- Covid and flu swab
- CXR
- Bloods: FBC, U&E, LFTs, CRP, Blood culture
These investigations help rule out differential diagnoses and assess the patient’s condition.
What is anaphylaxis?
A sudden, rapidly progressive systemic type I hypersensitivity reaction
Anaphylaxis is a severe allergic reaction that can be life-threatening.
What are common causes of airway compromise?
- Soft tissue swelling (anaphylaxis, infection)
- Inhaled foreign body
- Vomit, secretions, or blood in the airway
- Depressed level of consciousness (e.g. stroke, head injury, opioid overdose)
- Local mass effect (tumours, lymphadenopathy, etc)
- Trauma
- Laryngospasm (asthma, intubation, GORD, hypocalcaemia, etc)
These causes can lead to obstruction or difficulty in breathing.
Focused history taking for anaphylaxis?
AMPLE:
* Allergies
* Medications
* Past medical history
* Last meal
* Events leading to presenting
AMPLE is a mnemonic to gather critical information in emergency situations.
What is the mild presentation of an allergic reaction?
Urticaria +/- angioedema
Mild reactions may involve skin symptoms without respiratory distress.
What characterizes a moderate allergic reaction?
Mild symptoms + bronchospasm
Moderate reactions may lead to difficulty breathing but are not life-threatening.
What defines a severe allergic reaction?
Moderate symptoms + respiratory or haemodynamic compromise
Severe reactions require immediate medical intervention.
What is the recommended dose of IM adrenaline for adults?
500 mcg (0.5 ml 1 in 1,000)
Adrenaline is the first-line treatment for anaphylaxis.
How often can IM adrenaline be repeated if necessary?
Every 5 minutes
This is critical in managing anaphylaxis effectively.
What are other medications that may be used in the treatment of anaphylaxis?
- Antihistamines (IV chlorpheniramine 10 mg)
- Steroids for severe reactions (IV methylprednisolone 125 mg)
- Fluids (aggressive fluid resuscitation)
These medications help manage symptoms and prevent further complications.
What should be considered for wheeze in anaphylaxis?
Salbutamol nebulisers
Salbutamol can help relieve bronchospasm.
How long should patients be observed after an anaphylactic episode?
6-12 hours
Observation is necessary due to the risk of biphasic reactions.
What should be done for a patient after their first episode of anaphylaxis?
- Amend allergies on drug Kardex
- Refer for allergen testing
- Instruct on Epipen usage and prescription of 2 Epipens
- Safety net advice & emergency action plan
These steps help ensure patient safety and preparedness for future incidents.
When should serum tryptase levels be measured?
In cases of anaphylaxis at onset, at 3 hours, and 24 hours (if indicated)
Tryptase levels can help confirm anaphylaxis and monitor the reaction.
