Nitroglycerin/ NitroStat/ Nitrol/ Nitrolingual/ Nitro-Bid Ointment/ Tridil/ Nitro/ NTG

Question 1

Nitro Class

Answer 1

• Anti-anginal Agent
• Nitrate
• Coronary vasodilator

Question 2

Nitro Action

Answer 2

• Nitrates relax peripheral venous vessels, causing a pooling of venous blood and decreased venous return to the heart, which decreases preload.
• Nitrates reduce both arterial impedance and venous filling pressures, resulting in a reduction of the left ventricular systolic wall tension, which decreases afterload. Decreases preload.
• Results in the reduction of myocardial workload and myocardial oxygen demand.
• Aids in the reversal of pulmonary edema.
• It also causes some vasodilatation of coronary arteries (limited by atherosclerosis) increasing perfusion of ischemic myocardium.
• Note: Nitroglycerin relaxes all other types of smooth muscle.

Question 3

Nitro Indications

Answer 3

• Chest pain associated with angina
• Chest pain associated with AMI
• Acute pulmonary edema
• Symptomatic Hypertension (Hypertensive Crisis)

Question 4

Nitro Contraindications

Answer 4

• Head Injury, Increased ICP
• Cerebral hemorrhage
• Hypotension
• Hypovolemia
• Recent Viagra (sildenafil) use (OR similar drugs)
• Hypersensitivity to nitrate
• Constrictive Pericarditis, Pericardial Effusion
• Severe anemia (causes oxidation of hemoglobin to methemoglobin and could exacerbate anemia)

Question 5

Nitro Precautions

Answer 5

• Nitro deteriorates rapidly after bottle is opened, bottle should be opened and dated, and also protected from light.
• Use with caution in closed-angle glaucoma, may increase intraocular pressure.
• Elderly may be more susceptible to the effect of nitrates.
• Hepatic disease (metabolism may be impaired and lead to increased risk of methemoglobinemia)
• Postural hypotension.
• Pregnancy (C)

Question 6

Nitro Dosage

Answer 6

Adults:
• NTG Spray:
For discomfort suspicious of cardiac origin: SL: 0.4 mg SL spray/tab q 3-5 minutes PRN. Hold for B/P <100, or Viagra use (or similar drug) within previous 24 hours. Use with caution in suspected right-sided MI.
• HIGH DOSE NTG SPRAY: For patients in extreme respiratory distress, signs of severe pulmonary edema, with associated HTN (SYSTOLIC B/P > 200 mm HG): SL: 0.8 mg SL (0.4 mg spray/tab x2) q 5 minutes PRN. Hold for Viagra use (or similar drug) within previous 24 hours.
Return to normal dosing when B/P drops < 200 mm Hg.
• NTG Paste: Initiate if NTG is successful in reducing discomfort: TD: 0.5-1.5 inches applied topically (TD) to non-hairy area of trunk. Hold for B/P <100, or Viagra use (or similar drug) within previous 24 hours. Use with caution in suspected right-sided MI. Wipe off if hypotension develops
Pediatrics:
• Not normally recommended for prehospital use

Question 7

Nitro Onset/ Duration

Answer 7

• Onset: Tablet, Spray—1-3 min. Ointment—20-60 min. IV Immediate.
• Duration: Tablet, Spray—up to 30 min. Ointment—4-8 hours. IV—several min, dose dependent

Question 8

Nitro Side effects

Answer 8

• Headache due to vasodilation
• Hypotension, Dizziness
• N/V
• Xerostomia (Dry Mouth)
• Reflex tachycardia
• Skin rash, Flushing
• Anxiety
• Agitation
• Methemoglobinemia (rare, usually with high doses of the IV formulation, but can be seen with normal therapeutic doses)

Question 9

Nitro Interactions

Answer 9

• Alcohol (can theoretically produce additive hypotension)
• Aspirin results in increased serum nitrate concentrations (may cause increased hypotension, limited data)
• CCB and BB—additive interaction can result in symptomatic orthostatic hypotension.
• Sympathomimetics may antagonize the effects of nitro.
• May compromise the efficacy of alteplase, TPA when administered concomitantly