Resuscitation
Cardiac arrest
High-quality chest compressions are the single most important intervention: rate 100–120/min, depth 5–6 cm in adults, full recoil, minimal interruptions (target compression fraction above 80%), and a change of compressor every 2 minutes to limit fatigue. Ventilate at 30:2 without an advanced airway; once one is in place give continuous compressions and 10 breaths/min. Attach the defibrillator early and interpret the rhythm with the shortest possible pause.
Shockable rhythms (VF/pulseless VT) get an immediate unsynchronised shock, compressions resumed at once without a post-shock pulse check, adrenaline 1 mg IV/IO after the second or third shock then every 3–5 minutes, and amiodarone 300 mg after the third shock. Non-shockable rhythms (asystole, PEA) get adrenaline as early as possible, no atropine, and a systematic hunt for the 4Hs and 4Ts. Capnography is mandatory once an advanced airway is placed: an abrupt rise in ETCO2 to 40 mmHg or more is the earliest reliable sign of ROSC, while a persistent value below 10 mmHg predicts a poor outcome.
Common traps: interpreting a rhythm before compressions resume; prolonged pulse checks; mistaking agonal gasps for normal breathing; treating fine VF as asystole and withholding a shock; forgetting reversible causes in PEA, particularly tamponade, tension pneumothorax and massive pulmonary embolism, which need a procedure rather than more drug.
Rule of thumb: a narrow-complex PEA at a rate of 120 suggests mechanical obstruction - look for tamponade, pneumothorax or haemorrhage while compressions continue.
After ROSC: target SpO2 94–98%, normocapnia, MAP 65 mmHg or more, a 12-lead ECG, and temperature control with active avoidance of fever.