Anaphylaxis Flashcards
What signs may indicate a patient is developing an anaphylactic reaction while under anaesthesia?
- Mucocutaneous - Erythema, Urticaria, Angioedema
- Respiratory - Bronchospasm, cough, hypoxia, inc airway pressure
- CVS - Hypotension, tachycardia, arrythmia, CVS collapse, arrest
What is the usual timeframe for development of anaphylaxis?
Usually immediate, but can be delayed by 30-60mins
latex allergy is often delayed
Outline the immediate management of anaphylaxis
- Call for help
- Delegate someone to get - crash trolley and anaphylaxis kit
- Cease all suspected triggers
- Check ECG - commence CPR if losing cardiac output
- Intubate, reduce volatile, give 100% O2
- Infuse fluids, elevate legs and insert IAL
- Give adrenaline - 1mcg/kg bolus 1-2mins PRN
- If signs persist - start adrenaline infusion -> pt requires a CVL
- Consider adjuncts ONLY when haemodynamics are stable
- Collect blood for tryptase levels
- Contact ICU
What are the IV and IM adrenaline bolus doses for anaphylaxis?
- IV 0.25-1mcg/kg
- IM Adult 500mcg
- 6-12 300mcg
- <6 150mcg
How is an IV adrenaline infusion set up?
3mg of Adrenaline in 50mLs of 5% dextrose or 0.9% NaCl - mLs/hr = mcg/min
Commence at 7mLs/hr
How would you manage severe bronchospasm?
- In circuit bronchodilators - Salbutamol, Ipratropium
- Salbutamol IV bolus (15mcg/kg upto 250mcg)
- Magnesium 50mg/kg over 20mins - max dose 2gm
- Hydrocortisone 1-2mg/kg IV
What other drug options are available for patients poorly responsive to Adrenaline?
- Noradrenaline infusion 0.1mcg/kg/min
- Metaraminol infusion 10mg/50mL saline - start at 5mL/hr
- Vasopressin 2U/hr
- Glucagon 1-5mg over 5mins (b-blocker reversal)
What further adjuncts can be considered once the patient is stable?
- Steroids to prevent late response - Hydrocortisone 2-4mg/kg or Dexamethasone 0.2-0.4mg/kg
- 2nd Generation anti-histamine (Loratadine)
What is the ANZCA DRSABCD of anaphylaxis?
- Danger and diagnosis - hypotensive with bronchospasm - cease all triggers
- Send for help
- Airway - establish an airway if airway oedema or compromise
- Breathing - FiO2 1.0
- Circulation - CPR if no pulse, give 1mg Adrenaline and follow CPR protocol, IV fluid bolus 20mLs/kg and rpt as required
- Drugs - Adrenaline - bolus, rpt, infusion