Intrapartum fetal distress: Cardiotocographic evaluation at term pregnancy in low risk group

Amaç

To evaluate the predictive value of fetal cardiotocographic monitoring in the diagnosis of fetal distress and its correlation with fetal acid base status.

Study design

A comparative cohort study was designed, which included single fetuses with no previous risk factor, gestational age ≥37 week and vertex presentation and fetal distress in labor. Fetal distress criteria were recurrent or prolonged decelerations, fetal heart rate under 70 beats/minute lasting 60 seconds or more and continuing at least 30 minutes and/or baseline tachycardia. Control group was selected from the patients with no decelerations in fetal cardiotocography.

Bulgular

13091 infants were born at Zekai Tahir Burak Women’s Health Education and Research Hospital from 1 January to 30 December in 2010. There were 4132 fetuses in our cohort. 114 (2.2%) fetuses developed fetal distress during continuous monitoring. Mean maternal age was 26.2±5.3 years, mean maternal height was 160.8±4.9 cm, mean maternal weight 74.2±10.1 kg, mean maternal body mass index 28.6± 3.9 kg /m2, mean gestational age 39.9±1.2 weeks, mean fetal birth weight 3280.1±371.2 g, median gravidity was 1, and median parity was 0. There were 45 (39.5%) pregnancies with meconium stained amnion, 19 (16.7 %) premature rupture of membranes and 51 (44.7%) women were induced and/or augmented for labor. Mean pH was 7.22±0.14, mean PO2 31.4±15.6 mmHg, mean PCO2 56.8±19.2 mmHg, mean base deficit -6.1±7.9. Upon the definition of fetal metabolic acidosis, pH <7.0 and BE ≤ -12; 3 (2.4%) fetuses were acidemic. Thirteen (%11.4) fetuses were admitted to neonatal intensive care unit (NICU), 8 (7%) were entubated, 10 (% 8.7) had continuous positive airway pressure (CPAP), and 38 (%33.3) required oxygen support. One fetal death occurred secondary to meconium aspiration and bilateral pneumothorax.

Sonuç

Our study suggests that cardiotocographic monitoring at term pregnancy with no defined previous risk factors seems not to be an efficient tool to detect fetal metabolic acidosis.  

Anahtar Kelimeler

Fetal distress, cardiotocograph, hypoxia, fetal acidosis, neonatal intensive care unit

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