Changes in the rate of cardiac contractions are affected primarily by changes in which of the fol-lowing?
a. Sympathetic or parasympathetic tone
b. Ventricular afterload
c. Ventricular contractility
d. Ventricular preload
ANS: A
Those factors affecting heart rate are mainly of central origin (i.e., neural or hormonal).
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An EMT is presenting a continuing education class on the care of the pregnant female. When discussing the amniotic sac, he is correct to emphasize which of the following points?
A) "It contains fluid and surrounds and protects the uterus." B) "It contains a fluid called Wharton's jelly that enables the baby to breathe and move." C) "It must rupture during the second trimester of pregnancy for fetal development to progress." D) "It protects and insulates the baby during pregnancy."
________ is a term broadly used to refer to personnel in prehospital care
Fill in the blank(s) with correct word
In accelerated idioventricular rhythm, how do the QRS complexes appear?
A. They have a classic wide and bizarre appearance. B. They fall within the normal range of 0.12 to 0.20 seconds due to the heart rate. C. They are irregular because of multifocal ventricular impulses. D. They cannot be distinguished because the heart rate is too rapid.
What is often referred to as 'a clouding of consciousness'?
A) Delirium B) Delusions C) Hallucinations D) Psychosis