Nitrates & Nitrites

Indications:

• Treats:

  • Stable Angina

  • Unstable Angina

  • Vasospastic Angina

• Rapid Relief

  • Acute attacks

• Long-term

  • Prevent anginal episodes

Mechanism of Action & Effects:

• MOA:

  • Relaxes smooth muscles causing vasodilation, especially potent vasodilation in coronary arteries

• Effects:

  • Stable Angina

    • Decrease cardiac workload, reducing O2 demand

  • Unstable Angina

    • Potency of coronary vasodilation for immediate relief

  • Vasospastic Angina

    • Counters spasm for immediate relief

Forms:

• SL

• Chewable tabs

• Oral capsules/tabs

• IV

• Transdermal

• Ointments

• Translingual Sprays

Drugs

• Nitroglycerin

• Isosorbide dinitrate

• Isosorbide mononitrate

Isosorbide dinitrate (Isordil)

• Characteristics:

  • Organic

  • Produces consistent and steady therapeutic response

  • Better for long-term use

• Forms:

  • SL rapid acting

  • Immediate release tablets

  • Long-acting oral dosages

Nitroglycerin

• Characteristics:

  • Prototypical nitrate

  • Large first-pass effect with enteral forms

  • Most used drug to treat symptomatic ischemia

  • Better for emergencies due to titration abilities with IV

• Forms:

  • P.O, SL, metered spray, topical

  • IV:

    • BP regulation for perioperative HTN

    • HF treatment

    • Pulmonary edema associated with acute MI

    • HTN emergencies

Contraindications

• Anemia

  • Nitrates lower BP & O2 demand

• Closed angle glaucoma

  • Vasodilation properties can increase interocular pressure

• Severe head injury

  • Vasodilation increases intercranial pressure, dangerous if head injury is present

• Hypotension

• Use of ED drugs

  • Vasodilation + vasodilation no good

Adverse Effects

• Headaches

  • will diminish in intensity and frequency with continued use

• Reflex tachycardia

  • If blood pressure decreases too much, heart beats faster to raise

• Ortho hypotension

• Skin irritation

Tolerance

• When it occurs

  • Frequent nitrate use

  • Long acting forms

• Ways to prevent:

  • Tolerance break

Nursing Impplications

• Techniques/Guidelines of using SL nitrates

  • no chewing/swallowing

  • burning indicates potency

  • last about 3 months after bottle opened

• Storage:

  • Airtight container

  • Dark glass w/ metal cap

  • No cotton filler

• Techniques/Guidelines of using TOPICAL nitrates:

  • Site rotation

  • Removal of old patch

  • Do not leave patch on overnight to prevent tolerance

• Techniques/Guidelines for using IV nitrates:

  • Monitor vital signs frequently during acute angina

  • IV must be given with non-PVC tubing and bags

  • Discard blue, green , or dark red solutions

SL Nitro Procedure:

1. Cease activity and sit or lie down, do not try to drive to hospital

2. Take SL nitro

3. If angina does not relieve withing 5 minuets, call 911 and take another nitro

4. If angina does not relieve within 5 minuets, take a third tablet