NREMT Paramedic Cognitive ExamCardiology & ResuscitationMedium
A 50-year-old male presents with sudden onset of severe chest pain, diaphoresis, and nausea. His ECG shows ST elevation in leads II, III, and aVF. His blood pressure is 90/60 mmHg, and heart rate is 50 bpm. Which of the following medications is contraindicated in this patient?
- AOxygen
- BAspirin
- CNitroglycerin
- DMorphine
Show answer & explanationAnswer & explanation
Correct answer: C. Nitroglycerin
ST elevation in leads II, III, and aVF indicates an inferior myocardial infarction, which often involves the right ventricle. Patients with right ventricular infarction are preload-dependent, and nitroglycerin, a vasodilator, can cause a significant drop in blood pressure and worsen the patient's condition. The patient's current hypotension (90/60 mmHg) further contraindicates nitroglycerin.
Why the other options are wrong
- A. Oxygen is indicated for hypoxemia or signs of respiratory distress.
- B. Aspirin is indicated for acute coronary syndromes to prevent platelet aggregation.
- D. Morphine can be used for pain relief in STEMI, although it should be used cautiously with hypotension.
Nitroglycerin Contraindications in Inferior MI
Nitroglycerin is a vasodilator commonly used for chest pain in acute coronary syndromes. However, it is contraindicated in right ventricular (inferior) myocardial infarction, especially with hypotension, due to the risk of profound hypotension.
- Inferior MI often affects the right ventricle.
- Right ventricle is preload-dependent.
- Nitroglycerin reduces preload, which can lead to severe hypotension in RV infarction.
- Signs of RV infarction: ST elevation in II, III, aVF, often with bradycardia and hypotension.
Memory trick: Nitro-NO! for Low BP, RV-Oh-NO!