North Carolina EMT State Practice Exam

Which muscle response is impacted during an episode of ischemia?

1. Oxygen delivery to tissue

2. Blood pressure maintenance

3. Neural communication

4. Volume output from the heart

The correct answer is: Oxygen delivery to tissue

The correct response highlights that ischemia primarily affects oxygen delivery to tissues. Ischemia refers to a condition where there is a reduction in blood flow to a region, which consequently leads to a decrease in oxygen supply. Muscles, particularly during physical activity or in times of increased demand, rely heavily on an adequate oxygen supply to function efficiently. When ischemia occurs, due to blocked arteries or reduced blood flow from other causes, the muscle cells do not receive sufficient oxygen, which impairs their ability to contract and perform work. In this context, understanding ischemia is crucial, as it can lead to muscle cramping, fatigue, and in severe cases, muscle damage due to oxygen deprivation. This is particularly relevant in situations like coronary artery disease, where heart muscle experience ischemia, resulting in angina or even a heart attack if untreated. Other responses, while related to overall cardiovascular function, do not directly address muscle response: blood pressure maintenance concerns systemic vascular resistance and cardiac output, neural communication pertains to the nervous system's ability to transmit signals, and volume output from the heart relates to the amount of blood the heart pumps, which is affected by a combination of factors but not solely by the state of ischemia.