14.2 Cardiovascular Infusions

Cardiovascular drips demand continuous respect

Domain 3B Cardiovascular Infusions focuses on medications that acutely change blood pressure, vascular tone, heart rate/rhythm, or coagulation—often in critically ill or intermediate-care patients. Small rate errors cause hypotension, hypertension, arrhythmias, bleeding, or tissue necrosis from extravasation. The CRNI lens is device + pump + monitoring + compatibility + emergency response.

Quick Answer: Vasopressors constrict vessels / support BP (e.g., norepinephrine; dopamine dose-dependent). Inotropes boost contractility (e.g., dobutamine). Nitro products dilate (preload/afterload reduction concepts). Prefer central access for many vasopressors; always use a pump; dedicate a lumen when possible; monitor continuously. Vasopressor extravasation → stop + local antidote concepts (phentolamine; some use terbutaline). Amiodarone needs filter/compatibility attention. Heparin drips follow protocol labs and bleeding checks.

Inotropes vs vasopressors (and mixed agents)

Exam trap: Calling every “pressors drip” the same. Dobutamine is not a pure vasopressor; norepinephrine is not primarily an inotrope. Titrate to the ordered goal (MAP, SBP, cardiac index, symptom relief)—not to a generic “looks better.”

Core vasoactive agents—infusion nursing concepts

Norepinephrine

• Potent vasopressor commonly used for distributive shock (e.g., septic shock pathways).
• Central venous administration preferred; peripheral short-term use only under strict protocols with large proximal veins and intense site monitoring in some emergency pathways—still high extravasation risk.
• Continuous arterial-line or frequent noninvasive BP monitoring per acuity; never “set and forget.”

Dopamine

• Dose-dependent teaching: lower ranges more inotropic/renal dopaminergic effects historically taught; higher ranges more vasoconstriction.
• Still requires pump, monitoring, and extravasation caution.
• Arrhythmias possible—watch HR and rhythm.

Dobutamine

• Primarily inotropic support for low-output states (e.g., decompensated HF selected pathways).
• May cause tachycardia and arrhythmias; BP response variable (can decrease SVR).
• Continuous cardiac monitoring.

Nitroglycerin (IV)

• Venodilation (preload reduction) prominent; used in ACS/HF ischemic pathways per order.
• Hypotension and headache common; special tubing considerations may apply (adsorption to some plastics—follow product/pharmacy guidance).
• Titrate to pain relief/BP parameters as ordered; hold parameters matter.

Practical titration rules for all vasoactives

1. Use a smart pump with drug library when available; independent double-check of high-alert drips per policy.
2. Label lines at both ends; trace from bag to patient before rate changes.
3. Prefer a dedicated lumen—avoid bolusing unrelated meds into a vasopressor line that could deliver a hidden bolus or interrupt the drip.
4. When changing bags/syringes, minimize interruption of critical vasopressors (have next bag ready; follow double-pump handoff techniques per unit protocol).
5. Document rate, concentration, and clinical response (MAP, HR, urine, mentation, lactate trends as ordered).

Access, pumps, and monitoring standards

Why central access is preferred for many vasopressors

Vasopressors cause intense local vasoconstriction. If they leak extravascularly, tissue ischemia and necrosis can result. Central veins provide high flow and dilution. Institutional policies increasingly allow carefully protocolized short-term peripheral pressors in emergencies, but CRNI still expects you to:

• Know central preferred teaching for many continuous vasopressors.
• Escalate early for central access when drips will continue.
• Inspect peripheral sites constantly if a pressor runs peripherally under protocol.

Pump required

Vasoactive drugs are never free-flow gravity drips. Pumps prevent fatal bolus or underdose. Alarms for occlusion, air, and empty container are safety features—respond immediately.

Continuous monitoring

Vasopressor extravasation

Recognition

• Pain, burning, swelling at site
• Blanching, coolness, mottling along the path of extravasation
• Delayed tissue necrosis if untreated

Immediate management framework

1. Stop the infusion; do not continue “because BP is low”—switch to a patent central or alternate site immediately while supporting hemodynamics per team plan.
2. Leave or remove catheter per protocol after aspirating residual drug if directed.
3. Notify provider urgently; mark area.
4. Pharmacologic antidote concepts:
   • Phentolamine (alpha-adrenergic antagonist) is the classic local infiltration antidote teaching for catecholamine extravasation.
   • Terbutaline subcutaneous protocols appear in some institutional pathways as alternatives/adjuncts—know that specific antidote choice is protocol-driven.
5. Supportive care: elevation as directed, surgical consult if severe necrosis risk, photography/documentation.

Exam trap: Pulling the line and walking away without antidote consideration, or restarting the same infiltrated peripheral site.

Antiarrhythmic infusions—amiodarone high-level

IV amiodarone is common for ventricular and selected atrial arrhythmias.

Nursing concepts (high-level, not every brand quirk):

• Often administered with an in-line filter for certain concentrations/infusions per product labeling and pharmacy guidance.
• Compatibility is limited—do not assume Y-site compatibility with multiple drips; verify references.
• Central line preferred for higher concentrations in many policies; peripheral use may be limited by concentration/phlebitis risk.
• Monitor BP (hypotension with rapid infusion), HR/rhythm, and QTc/proarrhythmia concerns.
• Long half-life and multi-organ effects are medical management issues; nursing focuses on safe infusion setup and acute monitoring.

Other antiarrhythmics (e.g., lidocaine, procainamide, esmolol concepts) share the same meta-rules: pump, monitoring, concentration awareness, and rapid response to bradycardia/hypotension.

Heparin infusions

Unfractionated heparin continuous infusions are high-alert anticoagulants.

Safety pillars

Exam trap: Titrating heparin based on “how the patient looks” without protocol labs, or bolusing extra heparin after a bloody nose without orders.

Line management pearls for cardiovascular drips

• Trace the line every handoff: wrong concentration or wrong patient is a never-event pathway.
• Avoid co-infusing incompatible meds; when multiple vasoactives run, use multi-lumen central catheters thoughtfully.
• Carrier fluid rate changes can alter effective drug delivery in some low-rate setups—follow unit standards for dead-space management.
• On transfer, never clamp a critical vasopressor without a plan for immediate continuation.

Integrated mini-scenarios

Scenario A — Mixed identity: Orders for dobutamine for low cardiac output vs norepinephrine for refractory hypotension. Do not interchange them; goals and monitoring differ.

Scenario B — Peripheral blanching: Norepinephrine running in a forearm PIV; skin blanches and patient reports burning. Stop pressor in that site, establish alternative access, initiate extravasation protocol including phentolamine concepts per order.

Scenario C — Amiodarone setup: Nurse plans to Y-site amiodarone with multiple uncompatible drips without a filter when labeling requires one. Pause, check pharmacy/compatibility, use correct filter and access plan.

Scenario D — Heparin nomogram: aPTT critically high with oozing IV sites. Hold/adjust per protocol, notify provider, assess for major bleeding—do not silently continue the same rate.

High-yield exam traps

• Gravity-drip vasopressors or inotropes
• Ignoring central preference and extravasation risk for pressors
• Confusing inotrope with vasopressor goals
• Bolusing meds into a vasopressor lumen carelessly
• Missing phentolamine/terbutaline extravasation concepts
• Guessing amiodarone Y-site compatibility or skipping required filters
• Heparin rate changes without protocol labs
• Inadequate continuous BP/ECG monitoring during titration