Emergency Medical Technician (EMT) Basic Certification Practice Exam

In cases of severe respiratory issues, what sign is often associated with a loss of muscle tone?

1. Conversational speech

2. Bradycardia

3. Restlessness

4. Increased heart rate

The correct answer is: Bradycardia

In cases of severe respiratory issues, bradycardia is often a significant sign associated with a loss of muscle tone. When there is an inadequate supply of oxygen or when carbon dioxide accumulates in the bloodstream, the body can react by affecting the heart rate. Bradycardia, which is a slower than normal heart rate, can occur as the body responds to hypoxia (lack of oxygen). Loss of muscle tone often indicates weakness in muscle function, which can further compromise ventilation and oxygenation, leading to systemic effects including bradycardia. The parasympathetic nervous system can become dominant during respiratory distress, causing a decreased heart rate in contrast to what might be seen in a less severe situation, where increased heart rate could be a compensatory mechanism. Conversational speech typically remains intact because the person can still adequately ventilate, swallowing may not be severely impaired yet. Restlessness is often a non-specific sign indicating anxiety or discomfort, which can appear in many situations but is less directly connected to changes in muscle tone and heart rate. An increased heart rate tends to accompany less severe respiratory distress or might occur in response to initial hypoxia, but when muscle tone decreases drastically, bradycardia becomes a more telling sign of a deterior