[Atosiban as a tocolytic agent: a new proposal of a therapeutic approach].
OBJECTIVE
to test a therapeutic approach using atosiban for tocolysis, evaluating its safety and maternal and fetal side effects.


METHODS
prospective study with 80 pregnant women with preterm labor admitted for tocolysis.


METHODS
singleton pregnancy, regular uterine activity, cervical dilatation between 1 to 3 cm, cervical enfacement greater than 50%, 23 to 33 weeks and six days of gestational age, intact membranes, amniotic fluid index between 5 and 25, no maternal, fetal or placental diseases, no fetal growth restriction, no cervical incompetence, no fever.


METHODS
chorioamnionitis or fever during tocolysis. Atosiban group: women received 6.75 mg atosiban iv in bolus, 300 mcg/min for three hours, then 100 mcg/min for three hours and thirty minutes. If uterine activity persisted, it was maintained iv infusion of 100 mcg/min for 12.5 hand that so for as long as 45 hours.


METHODS
women received terbutaline (five ampoules, 500 mL crystalloid solution) iv infusion, 20 mL/h. If uterine activity persisted, infusion velocity was raised (20 mL/h) until uterine contractions were absent. The dose was maintained for 24 hours.


RESULTS
gestational age at birth was 29 weeks and five days to 40 weeks and six days. In atosiban group, the proportion of women who had not delivered at 48 hours was 97.5%, mean interval between tocolysis and birth of 28.2 days. In control group, birth occurred before 48 hours in 22.5% of the cases; mean interval between tocolysis and birth of 5.3 days. Maternal side effects were observed in 27.5% of cases of the atosiban group, none with tachycardia, dyspnea or tachypnea. In the control group, 75% of the cases referred palpitations, tachycardia, tachypnea or headache (drug infusion was interrupted in four cases). Fetal tachycardia was observed in 22.5% of the cases (n=9). No early neonatal death was observed.


CONCLUSIONS
the therapeutic approach used showed to be effective for tocolysis, with low incidence of maternal, fetal and neonatal side effects.
Cabar
Fábio Roberto
FR
Departamento de Obstetrícia e Ginecologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil. fabiocabar@uol.com.br
Bittar
Roberto Eduardo
RE
Gomes
Cláudia Messias
CM
Zugaib
Marcelo
M
D000328:Adult; D005260:Female; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D015149:Tocolytic Agents / Q000627:therapeutic use*; D014668:Vasotocin / Q000031:analogs & derivatives* / Q000627:therapeutic use
D015149:Tocolytic Agents; C047046:atosiban; D014668:Vasotocin