ACLS Drugs – Study Notes

ACLS = Advanced Cardiovascular Life Support

• Focus: care beyond BLS, includes IV medications, rhythms, and emergency protocols.

• Always follow your organization’s protocol.

Key ACLS Medications

1. Epinephrine

   • First-line for VFib & pulseless VT.

   • Dose: 1 mg IV every 3–5 min during arrest.

   • Increases coronary & cerebral perfusion.

   • Also used in anaphylaxis (0.3 mg IM) via EpiPen.

2. Atropine

   • First-line for symptomatic bradycardia (HR < 50 with symptoms).

   • Blocks vagus nerve → ↑ HR.

   • NOT used in asystole or PEA.

3. Adenosine

   • Used for stable SVT (narrow complex tachycardia).

   • Mechanism: blocks AV node to interrupt reentry pathways.

   • Contraindicated in WPW with AFib (can worsen to VFib).

4. Amiodarone

   • Antiarrhythmic.

   • Initial dose: 300 mg IV for VFib/pulseless VT.

   • Second dose: 150 mg IV.

   • Used for stable monomorphic VT and wide complex tachycardia.

5. Lidocaine

   • Alternative to amiodarone if not available.

   • Max dose: 3 mg/kg.

6. Magnesium Sulfate

   • First-line for Torsades de Pointes (polymorphic VT).

   • Mechanism: stabilizes cardiac membranes.

7. Dopamine

   • Used in symptomatic bradycardia (if atropine fails).

   • Infusion: 5–20 mcg/kg/min, titrate to BP & HR.

   • Also for severe hypotension unresponsive to fluids.

8. Calcium Chloride / Gluconate

   • For calcium channel blocker overdose.

   • For hyperkalemia-induced cardiac arrest → stabilizes cardiac membranes.

9. Glucagon

   • For beta-blocker overdose (↑ HR & contractility independent of beta receptors).

10. Naloxone (Narcan)

• For opioid overdose in cardiac arrest, given with epi + CPR.

11. Midazolam (Versed)

• Used to prevent shivering during therapeutic hypothermia (post-arrest care).

Fluids

• Normal saline (0.9% NaCl) → preferred in cardiac arrest resuscitation (esp. hypovolemia).

• Avoid mixing ACLS drugs with Lactated Ringers.

Quick Rhythm-Specific Meds

• VFib / pulseless VT → Epinephrine + Amiodarone (or Lidocaine).

• Stable SVT → Vagal maneuvers → Adenosine.

• Bradycardia (<50 symptomatic) → Atropine → Dopamine/Epinephrine if atropine fails.

• Torsades de Pointes → Magnesium sulfate.

• PEA / Asystole → Epinephrine + CPR (NO Atropine).

• WPW with AFib → Avoid Adenosine, beta-blockers, CCBs.

Rule of Thumb:

• Shockable rhythms → Epinephrine, Amiodarone.

• Non-shockable rhythms → Epinephrine + fix reversible causes (H’s & T’s)

• The H’s (Hypo– conditions)

• Hypovolemia – severe blood/fluid loss.

• 1. Hypoxia – low oxygen.

  2. Hydrogen ion (acidosis) – metabolic or respiratory acidosis.

  3. Hypo-/Hyperkalemia – potassium imbalance.

  4. Hypothermia – low body temperature.
     (Some guidelines also include Hypoglycemia as an “H,” though less emphasized.)

  The T’s (Tension/Thrombosis/Tamponade):

  1. Tension pneumothorax – collapsed lung with pressure on heart/lungs.

  2. Tamponade (cardiac) – fluid around heart preventing effective pumping.

  3. Toxins – drug overdose or poisoning.

  4. Thrombosis (pulmonary) – massive pulmonary embolism.

  5. Thrombosis (coronary) – acute myocardial infarction (heart attack).

  Mnemonic tip:

  • Think “H’s = metabolic/physiologic causes”

  • Think “T’s = traumatic/structural/toxic causes”