A 56-year-old male requests another dose of nitroglycerin for chest pain. His vitals are P 118, R 16, BP 106/86, and SpO2 94% on room air. What is the most appropriate action?

• A. administer oxygen by NRB
• B. administer oxygen by nasal cannula
• C. withhold his nitroglycerin at this time
• D. assist him in taking his nitroglycerin

Answer: (C)

Nitroglycerin lowers preload and afterload, which can cause a drop in blood pressure. The safest practice is to withhold another dose if the patient’s systolic blood pressure isn’t high enough to tolerate further vasodilation. In this scenario, the systolic pressure is 106 mmHg, which is near the lower limit for safely administering another nitro dose in many protocols. Pushing nitroglycerin here could lead to clinically significant hypotension and potentially worsen chest pain or cause dizziness or syncope.

His oxygenation isn’t a concern since SpO2 is 94% on room air, so there’s no immediate need to give supplemental oxygen. He is tachycardic, which may reflect ongoing ischemia, but adding another nitro dose could compromise perfusion if his BP drops further. Therefore the most appropriate action is to withhold nitroglycerin at this time and reassess, continuing other ACS management per protocol.