Oxygen target for acute coronary syndrome

• A. 90%
• B. 100%
• C. 95-98%
• D. 85-90%

Answer: (A)

In acute coronary syndrome, oxygen is not given routinely; it’s reserved for patients who are hypoxemic or showing signs of respiratory distress. When oxygen is used, the goal is to maintain a saturation that prevents hypoxia but avoids hyperoxia, which can worsen injury. A target around 90% SpO2 achieves this balance: it keeps oxygen delivery sufficient without pushing oxygen levels too high, which can cause vasoconstriction and oxidative stress that may harm the heart.

Keeping saturation at 100% or in the high normal range (like 95–98%) isn't necessary and can expose tissues to excess oxygen. Conversely, aiming for only 85–90% risks inadequate oxygen delivery during ongoing ischemia. In practice, check the patient’s SpO2, administer supplemental oxygen only if it’s below 90% or if there are signs of hypoxemia or respiratory distress, and adjust to keep around 90% if oxygen is being used.