4 J per kg and resume — shockable arrest

Structured clinical encounter — resuscitation leadership

This station tests whether the candidate leads a team to the right decision under time pressure, delivers the shock correctly, and runs the shockable-arrest algorithm without error. Marks reward confirming the rhythm and the pulse, the correct mode and dose, correct pad placement, immediate resumption of compressions, and the structured drug sequence. ^{[1] [6]}

Stem

An eight-year-old weighing 25 kilograms collapses in the waiting room while waiting to be seen. He had complained of chest discomfort an hour earlier. He is unresponsive and apnoeic. A nurse begins cardiopulmonary resuscitation. The monitor shows ventricular fibrillation. There is no pulse. The team looks to you. ^{[1] [2]}

Candidate tasks

1. Lead the rhythm and pulse assessment (2 minutes). Confirm ventricular fibrillation on the monitor and the absence of a pulse during a brief pause in compressions. State the rhythm and the decision aloud: shockable arrest, unsynchronised defibrillation. ^[1]
2. Select the mode and dose and place the pads (2 minutes). Select 4 joules per kilogram (100 joules). Confirm SYNC is off. Apply pads anterolateral or anteroposterior, firm and gel-coupled, not touching, clear of any device. ^{[1] [3]}
3. Deliver the shock and resume compressions (1 minute). Charge while compressions continue, call stand clear, confirm no contact, deliver, and resume cardiopulmonary resuscitation immediately without a pulse check. ^[1]
4. Run the shockable-arrest drug sequence (ongoing). After the second shock give adrenaline 10 micrograms per kilogram; after the third give amiodarone 5 milligrams per kilogram; reassess after each two-minute cycle. ^[1]