amyl nitrite (am-il nye-trite)
Therapeutic: antianginals, antidotes
Acute treatment of angina pectoris. Unlabeled Use: Acute management of cyanide poisoning. Diagnosis of cardiac murmurs.
Reduces systemic arterial pressure (reduces afterload). Forms methemoglobin, which combines with cyanide, forming a nontoxic compound (cyanmethemoglobin). Therapeutic Effects: Relief of angina pectoris. Prevention of fatal outcome in cyanide poisoning.
Adverse Reactions/Side Effects
CNS: headache, restlessness, dizziness, fainting, weakness. EENT: ↑ intraocular pressure. Resp: shortness of breath. CV: hypotension, tachycardia, flushing. Derm: cyanosis of lips, fingernails, or palms (indicates methemoglobinemia). GI: nausea. Hemat: HEMOLYTIC ANEMIA, METHEMOGLOBINEMIA.
PHYSICAL THERAPY IMPLICATIONS
Examination and Evaluation
Monitor signs of hemolytic anemia (unusual weakness and fatigue, dizziness, jaundice, abdominal pain), or methemoglobinemia (bluish coloring of the skin, lips, fingernails; headache; shortness of breath; lack of energy). Notify physician immediately if these signs occur.
Assess episodes of angina pectoris at rest and during exercise. Document whether drug therapy is helpful in reducing the frequency and severity of angina attacks.
Assess dizziness and syncope that might affect gait, balance, and other functional activities (See Appendix C). Some dizziness is expected immediately after administration, but residual balance problems and functional limitations should be reported to the physician and nursing staff, and the patient and family/caregivers should guard against falls and trauma.
Assess blood pressure periodically, and compare to normal values (See Appendix F). Report low blood pressure (hypotension), especially if patient experiences dizziness, fainting, or other symptoms.
Assess heart rate, ECG, and heart sounds, especially during exercise (See Appendices G, H). Report fast heart rate (tachycardia) or symptoms of other arrhythmias, including palpitations, chest discomfort, shortness of breath, fainting, and fatigue/weakness.
Design and implement aerobic exercise and endurance-training programs to improve coronary perfusion, reduce angina, and improve myocardial pumping ability.
Because of an increased risk of angina and arrhythmias, use caution during aerobic exercise and endurance conditioning. Terminate exercise if patient exhibits untoward symptoms (chest pain, shortness of breath, unusual fatigue), or displays other criteria for exercise termination (see Appendix L).
Avoid physical therapy interventions that cause systemic vasodilation (large whirlpool, Hubbard tank). Additive effects of this drug and these interventions will cause a dangerous fall in blood pressure.
To minimize hypotension, patient should lie down until after administration, and move slowly when resuming a more upright position after drug effects subside (approximately 10 min).
Make sure patient brings amyl nitrate ampules to all physical therapy appointments, and that this drug is readily available during exercise and other interventions.