The most common cause of decreased variability in the fetal heart ...

[codyclark]

The most common cause of decreased variability in the fetal heart rate (FHR) that lasts 30 minutes or less is:
 
  a. Altered cerebral blood flow. c. Umbilical cord compression.
  b. Fetal hypoxemia. d. Fetal sleep cycles.

Question 2

The nurse caring for a laboring woman is aware that maternal cardiac output can be increased by:
 
  a. Change in position. c. Regional anesthesia.
  b. Oxytocin administration. d. Intravenous analgesic.

[kilada]

Answer to Question 1

ANS: D
A temporary decrease in variability can occur when the fetus is in a sleep state. These sleep states do not usually last longer than 30 minutes. Altered fetal cerebral blood flow would result in early decelerations in the FHR. Fetal hypoxemia would be evidenced by tachycardia initially and then bradycardia. A persistent decrease or loss of FHR variability may be seen. Umbilical cord compression would result in variable decelerations in the FHR.

Answer to Question 2

ANS: A
Maternal supine hypotension syndrome is caused by the weight and pressure of the gravid uterus on the ascending vena cava when the woman is in a supine position. This reduces venous return to the woman's heart, as well as cardiac output, and subsequently reduces her blood pressure. The nurse can encourage the woman to change positions and avoid the supine position. Oxytocin administration, regional anesthesia, and intravenous analgesic may reduce maternal cardiac output.