A patient's heart rate increased from 80 bpm to 160 bpm. The nurse knows that what will follow is a(n)
a. Increase in diastolic filling time.
b. Decrease in cardiac output.
c. Increase in stroke volume.
d. Increase in contractility.
ANS: B
An increased heart rate would decrease the diastolic filling time and stroke volume, thus decreasing overall cardiac output. A decrease in cardiac output results from decreased stroke volume and/or decreased heart rate. An increase in stroke volume and contractility would cause a decrease in heart rate to maintain cardiac output.
You might also like to view...
A researcher is involved in the investigation of an individual's genetic abnormality. Which of the following situations could the researcher most likely rule out as the genetic cause of a mutation?
A) Loss of a cytosine-guanine base pair B) Formation of an adenine-uracil base pair C) Substitution of an adenine-thymine base pair for a cytosine-guanine base pair D) Insertion of an extra adenine-thymine base pair
Which action is most important to teach a patient prescribed to take allopurinol (Zyloprim) daily for gout?
a. "Avoid operating heavy machinery." b. "Drink plenty of water." c. "Avoid alcohol and caffeine." d. "Take the drug only when symptoms of gout are present."
To maintain patient safety, studies suggest that scheduling should avoid:
a. Rotating shifts. b. Weekends. c. 8-hour shifts. d. Mandatory overtime.
The nurse, caring for a patient recovering from an acute myocardial infarction, is planning interventions to reduce the risk of which type of shock?
1. Cardiogenic 2. Hypovolemic 3. Distributive 4. Obstructive