Angina pectoris (Table 4) is an acute coronary syndrome associated with transient ischemia to the myocardium. Hypoxia (and at times anoxia) results from diseases and conditions which lead to atherosclerosis and obstruction of coronary arteries by fatty deposits that limits and/or impairs coronary blood flow. Precipitating factors that increase cardiac oxygen demand in the presence of decreased perfusion of the myocardium include physical exertion, emotional stress, cold, recent meal. Unstable angina pectoris may occur spontaneously at rest.
Table 4. Angina Pectoris.
Prevention:
Identify at-risk patient
Reduce anxiety
Ensure profound local anesthesia
Use local anesthetic agents containing a vasoconstrictor congruent with the patient’s functional capacity
Signs and symptoms:
Mild to moderate substernal pain of sudden onset
Squeezing
Tight
Heavy
Radiates to the left shoulder, arm, and jaw
BP ↑ from baseline
Emergency response:
Place patient in an upright or semi-reclining position
Note the time and administer nitroglycerin
0.4 mg, tablet/spray, SL
Administer oxygen
2 to 4 L/min by nasal cannula
Reevaluate vital signs
If pain is not relieved 5 minutes after the initial dose, repeat nitroglycerin
0.4 mg, tablet/spray, SL
Reevaluate vital signs
If pain is not relieved 10 minutes after the initial dose, repeat nitroglycerin
0.4 mg, tablet/spray, SL
Reevaluate and record vital signs
In a conscious patient, chest pain lasting more than 10 minutes must be assumed to be due to unstable angina or myocardial infarction
Notify EMS
Monitor vital signs
If at any time the patient becomes unresponsive, no normal breathing, and no palpable pulse consider the diagnosis of cardiac arrest
Immediate CPR and defibrillation congruent with current recommendations
Nota bene:
Signs of recovery: pain subsides, vital signs return to baseline values
Signs of deterioration: persistent pain, unstable vital signs, altered mentation
Adverse reaction to nitroglycerin includes flushing, headaches, dizziness, nausea, and vomiting; syncope and paradoxical angina pectoris due to nitrate-induced vasodilation has been reported
