Material presented here is for informational purposes only & is not a substitute for formal ACLS training, nor is it intended as advice or directions for delivering medical treatment. Established practices at your institution may vary from the information presented  here.
The algorithms basically are in terms of too fast, too slow, and dead rhythms and continuing with the stroke and acute coronary syndromes as well. 
We will take the approach with all Algorithms of an unconscious patient as the BLS: CABD and if patient is conscious Primary (ABCs) and Secondary (5Hs and 5Ts) surveys.
If patient is unconscious BLS (Basic Life Support):
Primary Assessment:
C=Check for responsiveness and no breathing or abnormal breathing and Call code blue or 
      9-1-1 and Check Circulation (no more than 10 seconds) - If definite pulse not felt. Begin 
      Chest compressions for pulseless patient - hard and fast 100 - 120 beats per minutes
      30 compressions
A=Airway, Open airway using head - tilt - chin lift (if no trauma suspected)
B=Breathing, Breath for pt - 2 breaths - (each breath should cause chest rise - but wait no more than 10 seconds)
5 cycles (2 minutes) then 

D=Defibrillation, Check for and tx a shockable rhythm (V.fib/V.tach are the only two shockable rhythms, see Unstable Tachycardias for Cardioversion options (120-200Joules for biphasic defibrillators and 360J for monophasic defibrillators)

Secondary Assessment:

If Patient is awake, breathing with a pulse, then provide: A, B, Cs. Oxygen if needed, get a set of vital signs, put patient on a heart monitor. 
Assessment: SAMPLE=Signs and Symptoms, Allergies, Medications, Past medical history, Last meal eaten, Events (what happened)
Acute Coronary Syndromes

Acute Ischemic Stroke


Unstable Tachycardias

Tachycardias (narrow QRS complex)

Tachycardias (wide QRS complex)

Respiratory Arrest

V. Fib/Pulseless V. Tach. treated with Automated 
     External Difibrillator (AED)

Refractory V. Fib/Pulseless V. Tach

Pulseless Electrical Activity (PEA)

God   Knows
God   Knows