What medications should be administered in emergency situations such as cardiac arrest, toxicologic overdoses, and severe bradycardia?

Emergency Medications List

In emergency situations, the specific medications administered depend critically on the underlying etiology—cardiac arrest requires epinephrine and antiarrhythmics, toxicologic overdoses require targeted antidotes, and severe bradycardia requires atropine or chronotropic agents. 1, 2

Cardiac Arrest Medications

Shockable Rhythms (VF/pVT)

• Epinephrine 1 mg IV/IO after initial CPR and defibrillation attempts fail, repeat every 3-5 minutes 3
• Amiodarone 300 mg IV/IO for refractory VF/pVT (may give second dose of 150 mg) 3
• Lidocaine 1-1.5 mg/kg IV/IO as alternative to amiodarone 3
• Beta-blockers may be considered for shock-resistant pVT/VF 4

Non-Shockable Rhythms (PEA/Asystole)

• Epinephrine 1 mg IV/IO as soon as feasible, repeat every 3-5 minutes 3

Critical Caveat: While epinephrine improves return of spontaneous circulation (ROSC), it does not improve survival with favorable neurologic outcomes 3. Calcium and sodium bicarbonate should NOT be routinely administered during cardiac arrest 3.

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Toxicologic Overdose Antidotes

β-Blocker Poisoning

For life-threatening hypotension/bradycardia, the treatment hierarchy is:

1. High-dose insulin (Class I, LOE B-NR): 1 U/kg IV bolus, then 1-10 U/kg/h infusion—this is the PRIMARY therapy for refractory hypotension 1

   • Monitor for hypoglycemia, hypokalemia, volume overload
   • Superior to vasopressors alone with lower vasoconstrictive complications

2. Vasopressors (Class I, LOE C-LD): Readily available, act quickly—almost always initial therapy 1

3. Glucagon (Class IIa, LOE C-LD): 2-10 mg IV bolus (pediatric: 0.05-0.15 mg/kg), then 1-15 mg/h infusion 1

   • Anticipate vomiting

4. Atropine (Class IIb, LOE C-LD): 0.5-1.0 mg IV every 3-5 minutes up to 3 mg for bradycardia 1

5. VA-ECMO (Class IIa, LOE C-LD): For refractory cardiogenic shock despite maximal pharmacotherapy 1

Do NOT use: Intravenous lipid emulsion therapy (Class III: No Benefit) 1

Calcium Channel Blocker Poisoning

Treatment approach mirrors β-blocker toxicity:

1. High-dose insulin (Class I, LOE B-NR): Same dosing as β-blocker poisoning—PRIMARY therapy 1

2. Vasopressors (Class I, LOE C-LD): Norepinephrine most commonly used, doses up to 100 μg/min in adults 1

3. Calcium salts (Class I, LOE C-LD) 1:

   • Calcium chloride: 2000 mg IV (20 mg/kg pediatric), then 20-40 mg/kg/h infusion
   • Calcium gluconate: 6000 mg IV (60 mg/kg pediatric), then 60-120 mg/kg/h infusion
   • Target ionized calcium 1.5-2× upper limit of normal
   • Administer calcium chloride through central line, especially in children

4. Atropine (Class IIa, LOE C-LD): For bradycardia 1

5. VA-ECMO (Class IIa, LOE C-LD): Survival rates up to 77% in case series 1

Additional considerations:

• Methylene blue 1-2 mg/kg IV (max 5-7 mg/kg) for refractory vasodilatory shock, particularly with amlodipine 1
• Glucagon has variable response rates 1

Sodium Channel Blocker Poisoning (TCAs, Cocaine, etc.)

Sodium bicarbonate (Class I, LOE B-NR) is the definitive treatment 1:

• Adults: 50-150 mEq IV bolus (1 mEq/mL solution)
• Pediatric: 1-3 mEq/kg IV bolus (0.5 mEq/mL solution)
• Maintenance: Prepare 150 mEq/L solution, infuse at 1-3 mL/kg/h 1
• Monitor for hypernatremia, alkalemia, hypokalemia, hypochloremia

Mechanism: Both hypertonic sodium administration and alkalemia reverse sodium channel blockade

ECG findings preceding dysrhythmias:

• QRS prolongation
• Terminal rightward axis deviation (best seen in lead aVR)

Organophosphate/Carbamate Poisoning

Immediate treatment (Class I, LOE A):

1. Atropine 1:

   • Adults: 1-2 mg IV, doubled every 5 minutes until full atropinization
   • Pediatric: 0.02 mg/kg, doubled every 5 minutes
   • Maintenance: 10-20% of total loading dose per hour (up to 2 mg/h in adults)
   • Endpoint: Clear chest on auscultation, HR >80/min, SBP >80 mmHg
   • Much higher doses required than typical bradycardia

2. Benzodiazepines (Class I, LOE C-LD): Diazepam (first-line) or midazolam for seizures/agitation 1

3. Early endotracheal intubation (Class I, LOE B-NR) for life-threatening poisoning 1

4. Pralidoxime (Class IIa, LOE A) for organophosphates 1:

   • Adults: 1-2 g IV, then 400-600 mg/h infusion
   • Pediatric: 20-50 mg/kg IV, then 10-20 mg/kg/h infusion

5. Dermal decontamination (Class I, LOE C-EO) with appropriate PPE 1

Do NOT use: Succinylcholine or mivacurium (metabolized by cholinesterase) 1

Benzodiazepine Poisoning

Key principle: Standard airway management is preferred over flumazenil in most cases 1

• Naloxone first (Class IIa, LOE B-NR) if combined opioid/benzodiazepine poisoning suspected 1

• Flumazenil (Class IIa, LOE B-NR) ONLY in select patients 1:

  • Pure benzodiazepine poisoning confirmed
  • No contraindications present
  • Dose: 0.2 mg IV titrated up to 1 mg (pediatric: 0.01 mg/kg)

Flumazenil is HARMFUL (Class III: Harm, LOE B-R) when:

• Risk of seizures (chronic benzodiazepine use, seizure disorder)
• Risk of dysrhythmias (TCA co-ingestion, hypoxia)
• Undifferentiated coma with unknown substances 1

Flumazenil has NO role (Class III: No Benefit) in benzodiazepine-related cardiac arrest 1

Opioid Poisoning

Naloxone 1:

• IV/IO/IM: 0.2-2 mg (pediatric: 0.1 mg/kg)
• Intranasal: 2-4 mg, repeat every 2-3 minutes as needed
• Maintenance: Two-thirds of waking dose per hour
• Titrate to: Reversal of respiratory depression and restoration of protective airway reflexes—NOT full consciousness

Digoxin Poisoning

Digoxin immune Fab 1:

• Acute overdose: 1 vial per 0.5 mg digoxin ingested
• Chronic poisoning: Dose (vials) = [serum digoxin (ng/mL) × weight (kg)] / 100
• Acute overdose, critically ill, unknown dose: 10-20 vials
• Each vial contains 40 mg Fab; lower doses may be equally effective

Cyanide Poisoning

Hydroxylamine 5 g IV (pediatric: 70 mg/kg) 1

Alternative regimen:

• Sodium nitrite: 300 mg IV (pediatric: 6 mg/kg)—watch for hypotension
• Sodium thiosulfate: 12.5 g IV (pediatric: 250 mg/kg) 1

Local Anesthetic Toxicity

Intravenous lipid emulsion (ILE) 1:

• Initial: 1.5 mL/kg IV (up to 100 mL) of 20% lipid emulsion
• Infusion: 0.25 mL/kg/min for up to 30 minutes

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Severe Bradycardia (Non-Toxic)

First-Line Treatment

Atropine (Class IIa, LOE C-LD) 2:

• Dose: 0.5-1 mg IV, repeat every 3-5 minutes (maximum 3 mg)
• Pediatric: 0.02 mg/kg

Important exception: Atropine should NOT be used (Class III: Harm) in heart transplant patients without autonomic reinnervation 2

Refractory Bradycardia

Chronotropic agents (Class IIb, LOE C-LD) 2:

• Dopamine: 5-20 mcg/kg/min IV, start at 5 mcg/kg/min, increase by 5 mcg/kg/min every 2 minutes
• Isoproterenol: 20-60 mcg IV bolus or 1-20 mcg/min infusion titrated to HR
• Epinephrine: 2-10 mcg/min IV or 0.1-0.5 mcg/kg/min titrated to effect

Calcium Channel Blocker Overdose with Bradycardia

Aminophylline: 250 mg IV bolus for second- or third-degree AV block associated with acute inferior MI 2

10% calcium chloride: 1-2 g IV every 10 minutes 2

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Critical Pitfalls to Avoid

1. Do NOT give routine calcium or sodium bicarbonate in undifferentiated cardiac arrest 3

2. Do NOT use flumazenil in undifferentiated overdose or when TCA co-ingestion possible 1

3. Do NOT use succinylcholine in organophosphate/carbamate poisoning 1

4. Do NOT use atropine in heart transplant patients 2

5. Do NOT use ILE for β-blocker or CCB poisoning (ineffective) 1

6. Do NOT delay high-dose insulin in severe β-blocker/CCB toxicity—it is superior to vasopressors alone 1

7. Remember much higher atropine doses needed for organophosphate poisoning (doubled every 5 min until atropinization) versus typical bradycardia (0.5-1 mg every 3-5 min) 1