Cesarean delivery for suspected fetal distress among preterm parturients

Among preterm parturients (< 37 weeks) who underwent cesarean delivery for suspected fetal distress, to determine the factors associated with decision-incision time (DIT) of < or = 30 minutes and to assess if umbilical arterial pH < 7.10 is more common with DIT < or = 30 or > 30 minutes.

The peripartum course of all patients who had cesareans for suspected fetal distress over three years was reviewed. The inclusion criteria were reliable gestational age < 37 weeks and a single indication for cesarean delivery, suspected fetal distress. Twenty antepartum and intrapartum factors were used in a univariate analysis.

The mean DIT among the 84 parturients was 30.5 +/- 21.2 minutes, and 63% of patients had surgery started within 30 minutes. The incidence of pH < 7.10 was 20%. Multivariate analysis indicated that the two factors significantly associated with prolonged time to surgery were tachycardia with decreased variability (odds ratio [OR] 5.9, 95% confidence interval [CI] 1.6-21.6) and use of spinal anesthesia (OR 6.2, 95% CI 1.1-35.0). Though none of the 20 variables had significant univariate associations with neonatal acidosis at alpha = .05, those with P < .20 were considered in multiple logistic regression analysis. None of the 20 factors were associated with pH < 7.10, including DIT of > or = 30 minutes (OR 0.26, 95% CI 0.06-1.03).

DIT is likely to be > 30 minutes if cesarean delivery is due to decreased fetal heart variability or if spinal anesthesia is utilized; neonatal acidosis, however, is not significantly associated with a prolonged interval.