Heart rate patterns of the hydrocephalic fetus

A Systematic Review of Intrapartum Fetal Head Compression: What Is the Impact on the Fetal Brain?

Objective During labor the fetal head is subjected to pressure related to uterine contractions and maternal pushing. Here we systematically review what is known about fetal head compression and its effects on fetal intracranial pressure, oxygenation, blood flow and cerebral function, and the plausibility that it might cause isolated fetal brain injury. Study Design Systematic review of intrapartum fetal head compression and fetal brain injury in accordance with the MOOSE methodology. The PubMed database was searched using a combination of the terms "fetal," "head," "cranial," "extracranial," "pressure," and "compression." Additional references were obtained using multiple strategies. Results were evaluated, and relevant studies encompassing animal and human data using several approaches are summarized in this review. Results Studies support a significant increase in fetal extracranial pressure with contractions and pushing. However, available data do not support a concomitant significant relative increase in intracranial pressure, a reduction in cerebral circulation or oxygenation, or an impact on cerebral function. Conclusion A review of the literature indicates that fetal intracranial pressure is well protected from extracranial forces. Available data do not support intrapartum fetal extracranial pressure as a cause of fetal brain injury. Precis The fetal brain is relatively unaffected by intrapartum fetal head compression.

Intracranial pressure and fetal heart rate in a hydrocephalic fetus during labor

Intra-uterine pressure (IUP), intracranial pressure (ICP) and fetal heart rate (FHR) were simultaneously recorded during labor in a severely hydrocephalic fetus. After cephalocentesis, 600 ml of liquor cerebrospinalis was drained. ICP exceeded IUP, but the increase in ICP was less than the increase in IUP during most of the contractions. The FHR showed marked decelerations during uterine contractions and changed gradually into a persistent bradycardia. The pathophysiology of fetal heart rate patterns during labor is discussed and the literature has been reviewed.

The prevalence of congenital abnormalities in patients with positive contraction stress tests

Over a period of 10 years, 60,197 stress and nonstress tests were done in 25,313 patients. There were 229 (0.9%) positive tests. In 47.2% of patients who had positive tests, preeclampsia and hypertension were the indications for the test, followed by suspected intrauterine growth retardation (26.6%) (table I). The cesarean section incidence was 71%. The mean age of the patients was 32 years. Nine per cent of patients were 45 years or older, 7% between 40 and 44 years, 23% between 35 and 39 years, 30% between 30 and 34 years, 20% between 25 and 29 years, 7% between 20 and 24 years and 4% younger than 20 years. There were 13 intrauterine deaths of which 9 fetuses were regarded as too small to be delivered. Of the remaining 4 patients, intrauterine death occurred in 3 patients before cesarean section could be done and in the fourth a macerated twin was unexpectantly found when a cesarean section was done for fetal distress. Routine autopsies were not done on intrauterine deaths. The only external abnormality that could be found was an umbilical hernia. Apart from this abnormality there were 9 liveborn babies with congenital abnormalities. Four of these babies died neonatally, bringing the perinatal death rate up to 50%. Four babies (1.7%) had chromosomal abnormalities. These were trisomy-21 in two patients, a trisomy-18 and a true hermaphrodite. Ages of the patients with the trisomy-21 were 46 and 49 years. Other abnormalities were exomphalos, microcephalus with hypospadia, hydrocele, polysyndactyly and hypospadia.(ABSTRACT TRUNCATED AT 250 WORDS)

Pressure in the hydrocephalic fetal head during the first stage of labor

Intraamniotic pressure was studied in the 30th week of amenorrhea in relationship with fetal intracranial pressure with open-tip catheters. The fetus had a severe hydrocephalus (echoscopy 16 cm) due to a teratologic malformation of the cerebrum. Clinically nonoperative treatment was indicated. Intracranial pressure (X) was invariably higher than intraamniotic pressure (Y) between contractions: Y = 2.04 + 0.54 X, and during contractions: Y = 5.30 + 0.55 X. There was no definite relationship between intrauterine and intracranial pressure, and the fetal tachogram. A definite relationship was established with the supine position of the patient and decelerations in the fetal tachogram. It is suggested that when fetal cardiac decelerations are seen during the first stage of labor it seems advisable to look for factors such as umbilical cord compression and decrease of materno-placental perfusion rather than fetal head compression.