Cardiology and Resuscitation
Two branches
Split every cardiac call into the arrest patient and the perfusing patient. In arrest, the rhythm decides: shockable (VF/pulseless VT) gets immediate defibrillation and CPR; non-shockable (asystole/PEA) gets CPR and epinephrine. Epinephrine 1 mg every 3-5 minutes applies to all rhythms; amiodarone or lidocaine is for refractory VF/pVT. Always hunt reversible causes (the H's and T's). High-quality CPR means 100-120/min, 5-6 cm depth, full recoil, minimal interruptions, compressor rotation every 2 minutes, and ETCO2 as a quality marker (aim above 10, ideally above 20 mmHg).
Stable versus unstable
Unstable means electricity: synchronized cardioversion for unstable tachycardia, pacing for unstable bradycardia. Stable means drugs and time. Adenosine is for regular narrow-complex SVT only. Wide-complex tachycardia is VT until proven otherwise.
12-lead essentials
ST elevation in contiguous leads with reciprocal depression, new LBBB, posterior MI (ST depression in V1-V3 with tall R waves), and right ventricular infarct (elevation in V1 with inferior changes). RV infarcts are preload dependent, so nitrates can crash the pressure.
Traps
Pulse checks longer than 10 seconds, delaying the first shock, giving epinephrine before defibrillating VF, and treating wide-complex tachycardia as SVT. Also: PEA is a rhythm, not a diagnosis - the cause is the emergency.
Rule of thumb
No pulse plus VF/pVT equals unsynchronized shock; unstable with a pulse equals electricity (cardiovert or pace); stable equals drugs.