What emergency medications should be available in a cath lab setting for a patient undergoing a cath lab procedure?

Emergency Medications for Cardiac Catheterization Laboratory

Every cardiac catheterization laboratory must have oxygen, epinephrine, nitroglycerin, aspirin, atropine, and antihistamines immediately available, with additional resuscitation drugs and equipment positioned for rapid access during procedures. 1

Core Emergency Drug Requirements

Immediate Access Medications (Must Be in Room)

At the time of any cath lab procedure, oxygen, suction, and emergency medications including epinephrine must be readily available. 1 The following drugs should be positioned for immediate administration:

• Epinephrine (1:10,000 solution for IV/IO use): Primary drug for cardiac arrest, anaphylaxis, and severe bradycardia unresponsive to atropine 1, 2

  • Dose: 1 mg IV every 3-5 minutes during cardiac arrest
  • For anaphylaxis: 0.3-0.5 mg IM (1:1,000 solution) or 0.1-0.3 mg IV slowly (1:10,000 solution)

• Nitroglycerin (IV formulation): Essential for acute coronary syndromes, hypertensive emergencies, and coronary vasospasm during procedures 1, 3

  • Critical caveat: Nitroglycerin is contraindicated in patients who have taken phosphodiesterase-5 inhibitors (sildenafil) within 24-48 hours due to risk of severe hypotension 3
  • Must use non-PVC tubing to prevent drug absorption and ensure accurate dosing 3

• Atropine: For symptomatic bradycardia, particularly during vagal reactions common with femoral access 1, 2, 4

  • Dose: 0.5-1 mg IV, may repeat every 3-5 minutes up to 3 mg total

• Aspirin (chewable, 325 mg): Mandatory antiplatelet therapy for acute coronary syndromes 1

  • Should be administered immediately upon STEMI diagnosis if not already given

Secondary Emergency Medications (Immediately Accessible)

• Diphenhydramine or chlorpheniramine (injectable): For contrast reactions and allergic responses 1, 2

  • Dose: 25-50 mg IV for diphenhydramine

• Hydrocortisone (IV): For severe allergic reactions and anaphylaxis 5, 2

  • Dose: 100-250 mg IV for acute allergic reactions

• Anticoagulants: Must be immediately available for procedural use 1

  • Unfractionated heparin (UFH) or enoxaparin for STEMI patients undergoing primary PCI
  • Bivalirudin for patients at high bleeding risk

• Antiplatelet agents: For loading during acute procedures 1

  • Clopidogrel 600 mg loading dose (300 mg if >75 years)
  • Prasugrel or ticagrelor as alternatives
  • GP IIb/IIIa inhibitors for high-risk cases with extensive infarction

Resuscitation Equipment and Drugs

Advanced Cardiac Life Support Medications

• Amiodarone: For ventricular arrhythmias during procedures 1

  • Dose: 150 mg IV over 10 minutes for VT/VF, then infusion

• Lidocaine: Alternative antiarrhythmic, can be given endotracheally if IV access lost 6, 4

  • Dose: 1-1.5 mg/kg IV bolus

• Calcium chloride: For hyperkalemia, calcium channel blocker toxicity, or cardiac arrest 4

  • Important: Should NOT be given endotracheally 4

• Sodium bicarbonate: For severe metabolic acidosis during prolonged resuscitation 4

  • Should NOT be given endotracheally 4

Vasopressors and Inotropes

• Dopamine or norepinephrine: For cardiogenic shock and hypotension 1
• Vasopressin: Alternative vasopressor for cardiac arrest 1

Procedural Complications Management

Contrast Reaction Medications

Pre-medication with acetaminophen and diphenhydramine should be administered 30-60 minutes before procedures in high-risk patients. 1 However, corticosteroids should NOT be routinely used for pre-medication as they may affect outcomes. 1

For acute contrast reactions during the procedure:

• Diphenhydramine 25-50 mg IV immediately 2
• Hydrocortisone 100-250 mg IV for severe reactions 5, 2
• Epinephrine for anaphylaxis (see dosing above) 2

Coronary Vasospasm and No-Reflow

• Intracoronary nitroglycerin: 100-200 mcg boluses 1
• Intracoronary verapamil or diltiazem: For refractory vasospasm 1

Critical Pitfalls to Avoid

The most common medication error in the cath lab is administering nitroglycerin to patients who have recently used sildenafil or similar drugs, resulting in life-threatening hypotension. 3 Always verify phosphodiesterase-5 inhibitor use before any nitrate administration.

When using IV nitroglycerin, standard PVC tubing absorbs 40-80% of the drug, leading to unpredictable dosing. 3 Non-PVC administration sets must be used, and published dosing studies using PVC tubing will result in overdosing if non-PVC tubing is employed. 3

Endotracheal drug administration during cardiac arrest requires 2-3 times the IV dose for epinephrine and atropine, but should never exceed 2-3 mg for epinephrine due to depot effects causing prolonged tachycardia and hypertension. 6 Bretylium, diazepam, calcium salts, and sodium bicarbonate should never be given endotracheally. 4

Antithrombotic Preparatory Regimen

For STEMI patients being transferred for primary PCI, a preparatory pharmacological regimen should be initiated as soon as possible, including anticoagulant plus oral antiplatelet agents. 1 This includes:

• Aspirin 162-325 mg (chewed) 1
• P2Y12 inhibitor loading dose 1
• Anticoagulation (enoxaparin preferred, or UFH if enoxaparin unavailable) 1

Prasugrel should not be started in patients likely to undergo urgent CABG and should be discontinued at least 7 days before any surgery. 1 Additional bleeding risk factors include body weight <60 kg and concomitant use of warfarin or chronic NSAIDs. 1

Post-Procedure Monitoring Requirements

After any cath lab procedure, confirm that loading doses of P2Y12 inhibitors have been administered and prescriptions for at least 30 days of dual antiplatelet therapy are provided. 1, 7 Emergency medications must remain immediately available during the post-procedure observation period, as complications including stroke, bleeding, vascular complications, allergic reactions, and arrhythmias can occur. 1, 7