Disease relevance of Deceleration

• Fetal heart rate (FHR) decelerations resembling post-paracervical block (PCB) bradycardia were observed immediately after the inadvertent intrauterine injection of lidocaine hydrochloride [1].
• Continuous fetal heart rate monitoring revealed a pattern of fetal tachycardia, decreased variability and late and variable decelerations in association with a maternal serum ethanol level of 300 mg/dL [2].
• There was maternal cocaine abuse and poor prenatal care, and variable decelerations, abruptio placentae, and meconium-stained fluid occurred in the intrapartum period [3].

High impact information on Deceleration

• These results indicate that BMP-5 deficiency prevents age-related decelerations in chondrocytic proliferation and initiation of hypertrophic differentiation, suggesting a role of BMP-5 in inhibiting these processes [4].
• However, there was an acidotic arterial blood pH (7.19-7.29) and intrapartum fetal heart rate decelerations in all four infants without eNOS expression [5].
• Specifically, 41% of women given meperidine exhibited FHR decelerations within 40 minutes, compared with 34% given epidural analgesia (P =.353) [6].
• Apart from one episode of maternal sedation and fetal heart rate decelerations resulting from an excessive demand bolus, mothers and neonates tolerated the remifentanil without sequelae [7].
• OBJECTIVE: This study was designed to determine the relationship between maternal position and the incidence of prolonged decelerations after epidural bupivacaine or intrathecal sufentanil analgesia for labor [8].

Biological context of Deceleration

• CONCLUSIONS: Severe variable decelerations and decreased FHR variability at < 32 weeks' gestation are related to histologic evidence of acute inflammation [9].
• However, both steroids decreased baseline fetal heart rate, increased long term variation, increased short term variation, and decreased fetal movements on the first day after steroid administration, and decreased high fetal heart rate variation and decelerations on the second day [10].
• Previously, it was shown that instantaneous heart rate decelerations were eliminated by administration of atropine and concurrently heart rate baseline was elevated in late embryos [11].
• Pregnancies with PROM after second-trimester EFM were significantly more likely to have second-trimester decelerations than those without PROM (75.0 vs. 54.2%, p < 0.05) [12].
• Primary measures included: skin conductance; the electroencephalogram (EEG), from which cortical event-related potentials (ERP) and heartbeatevoked potentials (HBEP) were derived; and the electrocardiogram (ECG), from which cardiac decelerations/ accelerations were derived [13].

Anatomical context of Deceleration

• However, GGT activity in term infants with a history of perinatal events suggestive of stress (meconium passage in utero, fetal decelerations, tight nuchal cord, or difficult delivery) was significantly higher than in term infants without such perinatal history [14].
• V-shaped decelerations were sometimes found in the NST recordings of normal fetuses accompanied by fetal movements, but the incidence of this type of deceleration tended to decrease as the subjects reached full term [15].

Associations of Deceleration with chemical compounds

• Patients with prolonged decelerations after bupivacaine epidural anesthesia were matched with control patients [16].
• Prolonged decelerations occurred with equal frequency after epidural bupivacaine and intrathecal sufentanil (3.9%) [8].
• There was an increased incidence of late decelerations in the PGF 2 alpha groups as compared to spontaneous and Pitocin-stimulated labors [17].
• The overall incidence of FHR decelerations associated with the use of prostaglandin E2 (PGE2) was comparable to that encountered in unstimulated labor [18].
• Nonlinear methods of assessment yielded additional results: Cocaine introduces a high correlation between one beat and the next and a tendency for cardiac accelerations to be followed immediately by decelerations and vice versa [19].

Gene context of Deceleration

• RESULTS: Severe variable decelerations, when classified as categorical events (> or = 1/h to 2/h, > or = 2/h to < 4/h, > or = 4/h), were more frequent in the amniotomy group (chi2 for trend = 5.7, P = 0.017) [20].
• No PCB bradycardia occurred if there were no pre-PCB FHR decelerations (92 per cent accuracy) [21].
• The abnormal finding of women with nonperiodic fetal heart rate decelerations at 20 to 28 weeks may detect the fetus at risk for intrauterine death in pregnancies complicated by systemic lupus erythematosus or circulating anticoagulant [22].
• A P-R shortening was identified also with all decelerations of more than 40 bpm from the baseline, resulting in a negative PR-RR relationship [23].
• In all circumstances, monitoring of the fetus with PROM is essential, with a nonstress test performed every other day to assess variable decelerations or a daily biophysical profile performed, as previously recommended [24].

References