In the MONA protocol for ACS, which component provides analgesia and can reduce preload?

In the MONA protocol for ACS, which component provides analgesia and can reduce preload?

• A. Oxygen
• B. Aspirin
• C. Morphine
• D. Nitroglycerin

Answer: (C)

Morphine is used for analgesia in ACS, relieving chest pain and anxiety. Beyond pain relief, it causes venodilation, which lowers venous return to the heart and thus reduces preload (the filling pressure/volume of the ventricle). This decrease in preload lowers myocardial wall stress and oxygen demand, helping during ischemia. Oxygen helps with oxygenation, aspirin is an antiplatelet, and nitroglycerin dilates veins to reduce preload but doesn’t provide analgesia. So morphine best fits both parts of the question: analgesia and preload reduction.

Morphine is used for analgesia in ACS, relieving chest pain and anxiety. Beyond pain relief, it causes venodilation, which lowers venous return to the heart and thus reduces preload (the filling pressure/volume of the ventricle). This decrease in preload lowers myocardial wall stress and oxygen demand, helping during ischemia. Oxygen helps with oxygenation, aspirin is an antiplatelet, and nitroglycerin dilates veins to reduce preload but doesn’t provide analgesia. So morphine best fits both parts of the question: analgesia and preload reduction.