Emergency Medicine

28 Critical Care Emergencies

ANAPHYLAXIS

2 Respiratory manifestations:

(i) Dyspnoea, laryngeal oedema, hoarseness and stridor.

(ii) Cough, wheeze (bronchospasm), cyanosis.

(iii) Rhinitis and conjunctivitis.

3 Cardiovascular manifestations:

(i) Tachycardia, occasionally bradycardia.

(ii) Hypotension, with massive vasodilation.

(iii) Light-headedness, confusion, collapse with loss of consciousness.

4 Other manifestations:

(i) Gastrointestinal:

(a) odynophagia (difficult or painful swallowing)

(b) abdominal cramps or pain

(c) vomiting and diarrhoea.

(ii) Cutaneous:

(a) erythema

(b) local or widespread urticaria

(c) pruritus

(d) angioedema.

(iii) Miscellaneous:

(a) premonitory aura, anxiety, feeling of impending doom

(b) back pain, pelvic cramps.

5 Attach a cardiac monitor and pulse oximeter to the patient.

MANAGEMENT

1 Give high-dose oxygen via a face mask aiming for an oxygen saturation

above 94%, and place the patient supine or elevate the legs. Stop the delivery

of potential causative agent and call for help.

2 Laryngeal oedema and wheeze

(i) Give 1 in 1000 adrenaline (epinephrine) 0.3–0.5 mg (0.3–0.5 mL)

i.m. immediately into the upper outer thigh.

(ii) If rapid deterioration occurs, change to 1 in 10 000 or 1 in

100 000 adrenaline (epinephrine) 0.75–1.5 μg/kg i.v.; i.e. 50–100 μg or

0.5–1.0 mL of 1 in 10 000, or 5–10 mL of 1 in 100 000 adrenaline

(epinephrine) over 5 min i.v. The ECG must be monitored.

(iii) Give 1 in 1000 adrenaline (epinephrine) 2–4 mg (2–4 mL)

nebulized in oxygen while preparing the i.v. adrenaline

(epinephrine).

(iv) Give hydrocortisone 200 mg i.v. particularly for bronchospasm.

3 Shock and circulatory collapse

(i) Give 1 in 1000 adrenaline (epinephrine) 0.3–0.5 mg (0.3–0.5 mL)

i.m. immediately into the upper outer thigh, repeated every 5–10

min until improvement occurs.