Critical ER Medications - ICU Drug Reference

Essential medications for emergency and critical care

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Critical ER Medications

ICU Drug Reference for Emergency Medicine

🚨 Life-Saving Medications

Critical dosages, indications, and monitoring parameters for ICU/ER use

VASOPRESSORS & INOTROPES
Norepinephrine (Noradrenaline) Vasopressor
0.1-2 mcg/kg/min IV infusion

First-line vasopressor for septic shock and hypotension

Indications

  • Septic shock (first-line)
  • Cardiogenic shock
  • Neurogenic shock
  • Severe hypotension

Administration & Dilution

  • Concentration: 4 mg in 250 mL D5W or NS (16 mcg/mL)
  • Alternative: 8 mg in 250 mL (32 mcg/mL) for fluid restriction
  • Route: Central line preferred, large peripheral IV acceptable
  • Compatibility: Compatible with most IV solutions
  • Stability: Stable for 24 hours at room temperature

Contraindications

  • Hypovolemia (relative)
  • Mesenteric or peripheral vascular thrombosis
  • Profound hypoxia

Monitoring

  • Arterial blood pressure
  • Heart rate and rhythm
  • Urine output
  • Peripheral circulation
Epinephrine (Adrenaline) Vasopressor
1 mg IV push (arrest) / 0.1-1 mcg/kg/min infusion

First-line for cardiac arrest and anaphylaxis

Indications

  • Cardiac arrest (all rhythms)
  • Anaphylaxis
  • Severe asthma
  • Refractory shock

Administration & Dilution

  • Cardiac arrest: 1 mg (1:10,000) IV push undiluted
  • Anaphylaxis: 0.3-0.5 mg (1:1,000) IM or 0.1 mg (1:10,000) IV
  • Infusion: 1 mg in 250 mL D5W or NS (4 mcg/mL)
  • Route: IV/IO for arrest, IM for anaphylaxis
  • Compatibility: Compatible with NS, D5W, LR

Side Effects

  • Tachycardia, arrhythmias
  • Hypertension
  • Myocardial ischemia
  • Hyperglycemia
Dopamine Inotrope
2-20 mcg/kg/min IV infusion

Dose-dependent effects: renal (2-5), cardiac (5-10), vascular (>10)

Indications

  • Cardiogenic shock
  • Symptomatic bradycardia
  • Heart failure with hypotension
  • Renal protection (low dose)

Administration & Dilution

  • Standard: 400 mg in 250 mL D5W or NS (1600 mcg/mL)
  • Alternative: 800 mg in 250 mL (3200 mcg/mL)
  • Route: Central line preferred due to extravasation risk
  • Compatibility: Compatible with D5W, NS, not with alkaline solutions
  • Light sensitive: Protect from light during infusion

Contraindications

  • Pheochromocytoma
  • Ventricular fibrillation
  • Tachyarrhythmias
Dobutamine Inotrope
2.5-15 mcg/kg/min IV infusion

Positive inotrope with minimal vasopressor effect

Indications

  • Cardiogenic shock
  • Acute heart failure
  • Low cardiac output states
  • Stress testing

Side Effects

  • Tachycardia
  • Arrhythmias
  • Hypotension (vasodilation)
  • Increased myocardial oxygen demand
SEDATION & ANALGESIA
Propofol Sedative
1-2 mg/kg bolus / 25-100 mcg/kg/min infusion

Ultra-short acting sedative-hypnotic

Indications

  • ICU sedation
  • Procedural sedation
  • Induction of anesthesia
  • Status epilepticus

Administration & Dilution

  • Concentration: Use undiluted (10 mg/mL) or dilute 1:1 with D5W
  • Bolus: Give slowly over 20-30 seconds
  • Route: Large peripheral IV or central line
  • Compatibility: Do not mix with other medications
  • Storage: Discard after 12 hours if diluted, 6 hours if opened

Contraindications

  • Egg/soy allergy
  • Severe cardiac dysfunction
  • Severe hypotension

Monitoring

  • Blood pressure
  • Respiratory status
  • Triglycerides (long-term)
  • Propofol infusion syndrome
Fentanyl Opioid
1-2 mcg/kg bolus / 25-200 mcg/hr infusion

Potent synthetic opioid analgesic

Indications

  • Severe pain management
  • ICU analgesia
  • Procedural analgesia
  • Anesthesia adjunct

Side Effects

  • Respiratory depression
  • Sedation
  • Chest wall rigidity
  • Tolerance/dependence
Midazolam Benzodiazepine
0.02-0.1 mg/kg bolus / 0.02-0.2 mg/kg/hr infusion

Short-acting benzodiazepine for sedation and anxiolysis

Indications

  • ICU sedation
  • Procedural sedation
  • Status epilepticus
  • Alcohol withdrawal

Contraindications

  • Severe respiratory impairment
  • Sleep apnea syndrome
  • Myasthenia gravis
CARDIAC MEDICATIONS
Amiodarone Antiarrhythmic
150 mg IV over 10 min, then 1 mg/min × 6hr, then 0.5 mg/min

Class III antiarrhythmic for life-threatening arrhythmias

Indications

  • VF/pVT (after defibrillation)
  • Atrial fibrillation
  • Ventricular tachycardia
  • Supraventricular tachycardia

Administration & Dilution

  • Loading dose: 150 mg in 100 mL D5W over 10 minutes
  • Maintenance: 900 mg in 500 mL D5W (1.8 mg/mL)
  • Rate: 1 mg/min × 6hr, then 0.5 mg/min
  • Route: Central line preferred (phlebitis risk)
  • Compatibility: D5W only, incompatible with saline

Side Effects

  • Bradycardia, heart block
  • Hypotension
  • Pulmonary toxicity
  • Thyroid dysfunction

Monitoring

  • ECG monitoring
  • Blood pressure
  • Liver function tests
  • Thyroid function
Adenosine Antiarrhythmic
6 mg rapid IV push, then 12 mg if needed

Ultra-short acting for SVT termination

Indications

  • Paroxysmal SVT
  • AV nodal reentrant tachycardia
  • Diagnostic tool for wide QRS

Administration & Dilution

  • Concentration: Use undiluted (3 mg/mL)
  • Technique: Rapid IV push followed by 20 mL NS flush
  • Route: Large peripheral IV closest to heart (antecubital)
  • Timing: Push drug and flush as fast as possible
  • Half-life: <10 seconds - must give rapidly

Contraindications

  • 2nd/3rd degree AV block
  • Sick sinus syndrome
  • Asthma/COPD
  • Atrial fibrillation/flutter
Atropine Anticholinergic
0.5-1 mg IV every 3-5 min (max 3 mg)

Anticholinergic for symptomatic bradycardia

Indications

  • Symptomatic bradycardia
  • AV block (Mobitz I)
  • Organophosphate poisoning
  • Cholinergic crisis

Side Effects

  • Tachycardia
  • Dry mouth, urinary retention
  • Confusion, delirium
  • Paradoxical bradycardia (low dose)
RESPIRATORY MEDICATIONS
Albuterol (Salbutamol) Bronchodilator
2.5-5 mg nebulized q20min × 3, then q2-6hr PRN

Short-acting β₂-agonist bronchodilator

Indications

  • Acute asthma exacerbation
  • COPD exacerbation
  • Hyperkalemia (adjunct)
  • Bronchospasm

Side Effects

  • Tachycardia, palpitations
  • Tremor, nervousness
  • Hypokalemia
  • Hyperglycemia
Methylprednisolone Corticosteroid
125 mg IV q6hr or 1-2 mg/kg/day

Systemic corticosteroid for inflammation

Indications

  • Severe asthma exacerbation
  • COPD exacerbation
  • Anaphylaxis (adjunct)
  • Spinal cord injury

Side Effects

  • Hyperglycemia
  • Immunosuppression
  • Mood changes
  • GI bleeding risk
ANALGESICS & REVERSAL AGENTS
Morphine Opioid
2-10 mg IV/IM q2-4hr PRN or 0.1-0.2 mg/kg

Gold standard opioid analgesic

Indications

  • Severe pain
  • Acute coronary syndrome
  • Acute pulmonary edema
  • Post-operative pain

Contraindications

  • Respiratory depression
  • Paralytic ileus
  • Severe asthma
  • Head injury (relative)
Naloxone (Narcan) Reversal
0.4-2 mg IV/IM/IN, repeat q2-3min PRN

Opioid receptor antagonist for overdose reversal

Indications

  • Opioid overdose
  • Opioid-induced respiratory depression
  • Post-operative opioid reversal
  • Diagnostic tool

Administration & Dilution

  • IV/IM: Use undiluted (0.4 mg/mL or 1 mg/mL)
  • Intranasal: 2 mg/2 mL pre-filled device
  • Titration: Start with 0.04-0.1 mg IV, titrate to effect
  • Route: IV/IM/SC/IN/Endotracheal
  • Onset: 1-2 min IV, 2-5 min IM/SC

Monitoring

  • Respiratory rate and depth
  • Level of consciousness
  • Blood pressure
  • Re-sedation risk
Flumazenil (Romazicon) Reversal
0.2 mg IV over 15 sec, then 0.3 mg, then 0.5 mg q1min

Benzodiazepine receptor antagonist

Indications

  • Benzodiazepine overdose
  • Post-procedural reversal
  • Hepatic encephalopathy

Contraindications

  • Seizure disorder
  • TCA overdose
  • Chronic benzodiazepine use
  • Increased ICP

Clinical Pearls & Safety

💡 Dosing Considerations

  • • Always verify weight-based dosing
  • • Adjust for renal/hepatic impairment
  • • Consider drug interactions
  • • Monitor for cumulative effects

⚠️ Safety Alerts

  • • Double-check high-alert medications
  • • Use infusion pumps for vasoactives
  • • Monitor for extravasation
  • • Have reversal agents available

📊 Monitoring Parameters

  • • Continuous ECG monitoring
  • • Arterial blood pressure
  • • Urine output hourly
  • • Neurological assessments

🔄 Drug Compatibility

  • • Check Y-site compatibility
  • • Separate incompatible drugs
  • • Use dedicated lines for vasoactives
  • • Flush lines between medications

Interactive Nursing Calculator

kg
mcg/kg/min

Quick Dilution Reference

💉 Standard Vasopressor Dilutions

Norepinephrine: 4 mg in 250 mL = 16 mcg/mL
Epinephrine: 1 mg in 250 mL = 4 mcg/mL
Dopamine: 400 mg in 250 mL = 1600 mcg/mL
Dobutamine: 250 mg in 250 mL = 1000 mcg/mL
Vasopressin: 20 units in 100 mL = 0.2 units/mL

🧪 Cardiac Drug Dilutions

Amiodarone: 150 mg in 100 mL D5W
Adenosine: Use undiluted (3 mg/mL)
Atropine: Use undiluted (0.1 mg/mL)
Lidocaine: 4 mg in 250 mL = 16 mg/mL
Procainamide: 1000 mg in 250 mL = 4 mg/mL

💤 Sedation Dilutions

Propofol: Use undiluted (10 mg/mL)
Fentanyl: 250 mcg in 250 mL = 1 mcg/mL
Midazolam: 50 mg in 250 mL = 0.2 mg/mL
Morphine: 50 mg in 250 mL = 0.2 mg/mL
Ketamine: 500 mg in 250 mL = 2 mg/mL

🔄 Reversal Agents

Naloxone: Use undiluted (0.4 mg/mL)
Flumazenil: Use undiluted (0.1 mg/mL)
Sugammadex: Use undiluted (100 mg/mL)
Protamine: Use undiluted (10 mg/mL)

⚠️ Critical Dilution Safety Points

  • • Always double-check calculations with another nurse/pharmacist
  • • Use standardized concentrations when possible
  • • Label all syringes and infusion bags clearly
  • • Verify compatibility before mixing medications
  • • Use infusion pumps for all vasoactive medications

Emergency Protocols

🚨 Cardiac Arrest Protocol

High-quality CPR + early defibrillation + appropriate medications

  • • Epinephrine 1 mg IV every 3-5 minutes
  • • Amiodarone 300 mg IV after 3rd shock (VF/pVT)
  • • Consider reversible causes (H's and T's)

⚡ Rapid Sequence Intubation

Preparation + Preoxygenation + Pretreatment + Paralysis + Positioning + Placement + Post-intubation

  • • Etomidate 0.3 mg/kg + Succinylcholine 1.5 mg/kg
  • • Alternative: Propofol + Rocuronium
  • • Post-intubation sedation: Propofol + Fentanyl

💧 Shock Management

Identify type + Fluid resuscitation + Vasopressor support

  • • Septic shock: Norepinephrine first-line
  • • Cardiogenic shock: Dobutamine ± Norepinephrine
  • • Anaphylactic shock: Epinephrine IM/IV