Maternity Nursing Q 54

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This drug is usually given parenterally to enhance uterine contraction:

  

     A. Terbutaline

     B. Pitocin

     C. Magnesium sulfate

     D. Lidocaine

    

    

Correct Answer: B. Pitocin

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The common oxytocin given to enhance uterine contraction is Pitocin. This is also the drug given to induce labor.

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Option A: Terbutaline, sold under the brand name Bricanyl among others, is a ?2 adrenergic receptor agonist, used as a “reliever” inhaler in the management of asthma symptoms and as a tocolytic (anti-contraction medication) to delay preterm labor for up to 48 hours.

Option C: Magnesium sulfate is often quite effective in slowing contractions, although this effect and how long it lasts varies from woman to woman. Like all tocolytic medications, however, magnesium sulfate does not consistently prevent or delay preterm delivery for a significant period of time. The most common explanation is that magnesium lowers calcium levels in uterine muscle cells. Since calcium is necessary for muscle cells to contract, this is thought to relax the uterine muscle.

Option D: The local anesthetic is transferred to the fetus slowly, and its margin of safety is also increased. Considering how local anesthetics have small direct effects on the fetus even at submaximal doses, lidocaine may be considered relatively safe for use in pregnant women.

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