Cardiac arrest
The probable cause is one or more of: something related to surgery or anaesthesia; the patient's underlying medical condition; the reason for surgery; equipment failure. The first priority is to start chest compressions, then get help, then find and treat the cause using the guideline.
4 H's, 4 T's:
Hypoxia (→ 2-2)
Hypovolaemia
Hypo/hyperkalaemia
Hypothermia
Tamponade (→ 3-9)
Thrombosis (→ 3-5)
Toxins
Tension pneumothorax
Specific peri-operative problems:
Vagal tone
Drug error
Local anaesthetic toxicity (→ 3-10)
Acidosis
Anaphylaxis (→ 3-1)
Embolism, gas/fat/amniotic (→ 3-5)
Massive blood loss (→ 3-2)
Fluid bolus 20 ml.kg⁻¹ (adult 500 ml).
Adrenaline 10 µg.kg⁻¹ (adult 1000 µg – may be given in increments).
Atropine 10 µg.kg⁻¹ (adult 0.5–1 mg) if vagal tone likely cause.
Amiodarone 5 mg.kg⁻¹ (adult 300 mg) after 3rd shock.
Magnesium 50 mg.kg⁻¹ (adult 2 g) for polymorphic VT/hypomagnesaemia.
Calcium chloride 10% 0.2 ml.kg⁻¹ (adult 10 ml) for magnesium overdose, hypocalcaemia or hyperkalaemia.
Thrombolysis for suspected massive pulmonary embolus.
Continue compressions while charging: Biphasic 4 J.kg⁻¹ (adult 150–200 J).
DO NOT check pulse after defibrillation.
Use 3 stacked shocks in cardiac catheterisation lab.
Use waveform capnography. No expired CO2 = lungs not being ventilated (assume and exclude oesophageal intubation). Very rarely, absent/minimal expired CO2 = CPR not occurring OR pulmonary circulation disconnected from systemic (e.g. in major trauma). Sudden increase in ETCO2 usually signals return of spontaneous circulation.
Optimise position for chest compressions (use overhead for bariatric patients).
Uterine displacement in pregnant patients.
Ventilator can free up hands but remember to set to volume control. Minimise intrathoracic pressure: avoid excessive tidal volume and hyperventilation.