Randomized comparison of intravenous terbutaline vs nitroglycerin for acute intrapartum fetal resuscitation.
OBJECTIVE
The purpose of this study was to compare terbutaline and nitroglycerin for acute intrapartum fetal resuscitation.


METHODS
Women between 32-, 42 weeks' gestation were assigned randomly to 250 microg of terbutaline or 400 microg nitroglycerin intravenously for nonreassuring fetal heart rate tracings in labor. The rate of successful acute intrapartum fetal resuscitation and the maternal hemodynamic changes were compared. Assuming a 50% failure rate in the terbutaline arm, we calculated that a total of 110 patients would be required to detect a 50% reduction in failure in the nitroglycerin group (50% to 25%), with an alpha value of .05, a beta value of .20, and a power of 80%.


RESULTS
One hundred ten women had nonreassuring fetal heart rate tracings in labor; 57 women received terbutaline, and 53 women received nitroglycerin. Successful acute resuscitation rates were similar (terbutaline 71.9% and nitroglycerin 64.2%; P = .38). Terbutaline resulted in lower median contraction frequency per 10 minutes (2.9 [25-75 percentile, 1.7- 3.3] vs 4 [25-75 percentile, 2.5- 5]; P < .002) and reduced tachysystole (1.8% vs 18.9%; P = .003). Maternal mean arterial pressures decreased with nitroglycerin (81-76 mm Hg; P = .02), but not terbutaline (82-81 mm Hg; P = .73).


CONCLUSIONS
Although terbutaline provided more effective tocolysis with less impact on maternal blood pressure, no difference was noted between nitroglycerin and terbutaline in successful acute intrapartum fetal resuscitation.
Pullen
Kristin M
KM
Department of Obstetrics and Gynecology, Stanford University, Stanford, CA, USA.
Riley
Edward T
ET
Waller
Sarah A
SA
Taylor
Larisa
L
Caughey
Aaron B
AB
Druzin
Maurice L
ML
El-Sayed
Yasser Y
YY
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D005260:Female; D005316:Fetal Distress / Q000188:drug therapy*; D005333:Fetus; D006340:Heart Rate, Fetal / Q000187:drug effects*; D006801:Humans; D007231:Infant, Newborn; D005996:Nitroglycerin / Q000627:therapeutic use*; D011247:Pregnancy; D011256:Pregnancy Outcome; D012151:Resuscitation / Q000379:methods*; D018709:Statistics, Nonparametric; D013726:Terbutaline / Q000627:therapeutic use*; D015149:Tocolytic Agents / Q000627:therapeutic use*; D014590:Uterine Contraction / Q000187:drug effects
D015149:Tocolytic Agents; D005996:Nitroglycerin; D013726:Terbutaline